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At least 469 records · Page 26Linked to original sources

PubMed1975

[The vascularisation of the periorbita].

1. The periorbita is extensively vascularised from the side of the bone and the orbita. The vessels are interconnected so that the periost is not vascular boder area. 2. In the periorbita of the adult there is a dense capillary plexus which is less close-meshed on the inside. 3. Meandrian arteries and vascular loops exceptionally as long as 6 mm were found in the inner layers of the periorbita and in the adjacent layers of the fat connective tissue. 4. Flat membranes of fat connective tissue which are connected with the inner layer of the periorbita by long vascular streaks about on the inner surfaces of the periorbita. 5. On the outer surface of the periorbita venules 40 to 60 mum wide were found entering the periorbital bone. In the fissures area further meandering venules and venes were found which open in the cavernous sinus (in addition to the Vv. ophthalmicae) or enter the bordering bone. 6. N. and A. infraorbitalis run outside of the periorbita. 7. The nerves leave the periorbita by special channels and run through near and husk-like processes of the periorbita which accompany them up to the outer periost. In the bone they five off bone vessels.

Adipose Tissue↗

PubMed1975

[The subcutaneous vascular system (lower extremity): studies on micro-preparations].

At the level of fascial penetration the cutaneous arteries of the lower extremity are constantly accompanied by 1 or 2 communicating veins of varying diameter. Usually, they penetrate the fascia in rows via the muscular interstitium. There they give up branches to the fascial vascular network, to pre- and subfascial areolar tissue and possibly to the muscle origins on the fascia, or to the intermuscular septa. The texture of the fascia itself determines the structure of fascial openings for the cutaneous vessels. In the subcutaneous tissue the arteries are accompanied by 1 or 2 veins (Vv. comitantes). Numerous arterio-arterial and intervenous anastomoses form a subcutaneous network of vascular bundles. Two anastomosing venous systems can be distinguished in the subcutis: The small Vv. comitantes are fed primarily by the subcutaneous adipose lobes, and end in communicating veins or flow into the subcutaneous veins (epifascial veins). These large subcutaneous veins on the other hand are responsible for the actual outflow from the venous network of the cutis. They form the saphenous system or empty into larger communicating veins. Between the subcutaneous arterioles and accompanying venules there are numerous capillary webs. In addition direct capillaries and looped as well as meandering or knotted arterio-venous shunts are found. The subcutaneous vascular bundles are fixed by a connective tissue. There are often typical capillary meshes within arterial sheat, oriented like a rope-ladder. They undergo prenatal development. The subcutaneous (epifascial) veins are surrounded by areolar tissue on the cutaneous as well as on the fascial side. Fibers from the accompanying connective tissue criss-cross into the adventitia and thereby anchor the veins in a movable fashion. Typical vascular patches with plane capillary networks characterize the areolar tissue around the subcutaneous veins, which is differentiating at the 2nd half of the fetal period. Within are also capillary loops and convoluted arterio-venous shunts.

Adult↗

PubMed2002

Kissimmee River restoration: a case study.

Channelization of the Kissimmee River transformed a 167 km meandering river into a 9 metre deep, 75 metre wide, 90 km drainage canal (C-38) that is compartmentalized with levees and water control structures into a series of five stagnant pools. Channelization dramatically changed water level and flow characteristics, drained 21,000 hectares of floodplain wetlands and severely impacted fish and wildlife populations. A $500 million dollar restoration project will restore the ecological integrity of the river-floodplain system by reconstructing the natural river channel and reestablishing hydrologic processes. Sixty expectations have been established to quantify the ecosystem's recovery. The first phase of reconstruction was completed in February 2001 and included movement of 9.2 million cubic metres of earth to backfill 12 km of C-38, the explosive demolition of one water control structure, construction of two sections (2.4 km) of new river channel, and reestablishment of 24 contiguous km of river. Numerous social, political, and technical challenges have been encountered during the project's evolution. Recommendations are provided for future restoration projects.

Conservation of Natural Resources↗

PubMed2002

[Mechanisms of atrial fibrillation].

Atrial fibrillation occurs because of a complex interaction between an arrhythmogenic substrate, triggers factors and the autonomic nervous system. Underlying fundamental mechanisms are multiple, can cohabit and include schematically: multiple wavelet, stable microreentry, macro single meandering spiral wave reentry and focal atrial fibrillation arising from the pulmonary veins. More over, new concepts have emerged like the atrial fibrillation-induced electrical and structural remodeling which favors its own perpetuation. Experimental studies have shown a complex interaction between anatomical particularities of the atria and the activation fronts dynamic. All this recent progress open new and more efficient therapeutic perspectives for patients enduring atrial fibrillation.

Atrial Fibrillation↗

PubMed2002

Spontaneous rupture of a dissection of the left ovarian artery.

A 53-year-old female was suddenly hospitalized with acute left lateral abdominal pain. There was no history of trauma to the abdomen. She had received no abdominal operation. X-ray showed a soft tissue shadow in the left flank which displaced the bowel shadows medially. Plain abdominal CT showed a left retroperitoneal hematoma. Dynamic abdominal CT showed an outflow of medium from a blood vessel in the hematoma. At laparotomy, the source of bleeding was found to be the left ovarian artery. The ovarian artery was dilated and meandered remarkably. The ovarian artery and vein were ligated proximally and left adenectomy was performed. The patient made an uneventful recovery. Histological examination suggested a spontaneous rupture of a dissection of the left ovarian artery.

Abdomen, Acute↗

PubMed2003

[Chlamydia pneumoniae--the etiologic agent of follicular conjunctivitis followed by keratoconjunctivitis sicca in adult patients].

The authors refer to 21 adult patients at the age of 22 to 87 years, who have suffered from a chronic form of follicular conjunctivitis, found to be caused by Chlamydia pneumoniae as the etiological agent. The observation was made in the period from July 1999 to December 2002. Chl. pneumoniae was detected by a direct demonstration of the conjunctiva smears and by means of serological examination. The print preparations on glass were examined by the method of indirect immunofluorescence by means of specific monoclonal antibodies (Medac, Germany). The serological examination included detection of genus-specific IgG, IgA, IgM antibodies, respectively (Medac, Germany) and species-specific anti-Ch. pneumoniae IgG, IgA abd IgM antibodies, respectively (FOCUS Technologies, U.S.A.). The clinical picture included various long-term subjective complaints (within the range of several months to ten years), particularly a pathological secretion or increased lacrimation, cutting, burning or feeling of a foreign body in the eye. The objective examination revealed chronic changes characterized by a mild edema of bulbar conjunctiva with increased meandering in vessels of irregular caliber and edema in the lower transition plica with follicular structure crossing into the tarsal conjunctiva. In the fornix there was an apparent sticking aqueous or mucinous secretion. The therapy was indicated by the positive smears alone in four patients or positive IgA and/or IgM of genus- or species-specific antibodies in 12 patients. The therapy in the remaining five patients was recommended by the combination of suspect-positive smears in combination with positive genus- or species specific antibody reaction. The therapy made use of systemic administration of a macrolide antibiotic, azithromycin, for the period of 12 to 14 days in a single course of treatment. The pretreatment was always followed by control smears after two weeks and by serological examinations after three and six months. The serological findings remained virtually unchanged during that period of time in all patients under observation. In two of them only the species-specific antibodies anti-Ch. pneumoniae IgA antibodies disappeared six months after the therapy. The clinical findings disappeared slowly, particularly the follicular changes occurred after more than six months after the therapy ended. The subjective complaints, accompanied by a transient hyperemia of conjunctives in particular, remained after the therapy in nine patients older than 45 years, who were found to suffer from kieratoconjnunctivitis sicca. The ocular symptomatology was not accompanied by symptoms of autoimmune disease. The general treatment by antibiotics and the results supportive treatment succeeded in 67% of patients who were completely free of subjective complaints and the pathological process in conjunctives was inhibited.

Adult↗

PubMed2003

The river Ganga of northern India: an appraisal of its geomorphic and ecological changes.

The Ganga is the most important perennial river originating from Gangotri in the snow-bound Himalayas about 3,900 m above mean sea level. Gorging a distance of about 220 km in the Himalayas, it enters the plain at Hardwar and after meandering and braiding over a distance of about 2,525 km through the Indo-Gangetic plains, ultimately joins the Bay of Bengal. The course of this river has been changed due to: (i) subsurface geotectonic movement leading to change in slope of the deltaic plain and subsidence of the Bengal basin; (ii) changing pattern of water discharge with time; (iii) variations in sediment load. The environment of Ganga basin is also deteriorating with time due to severe natural episodes of periodic floods and storms as well as anthropogenic factors such as population growth, deforestation, agricultural activities, urbanisation, fertiliser and fossil fuel consumption and construction activities such as dams and bridges. All these have inconceivable adverse impacts on the health and natural regeneration capacity of the river basin. The presence of micropollutants in water and sediments of this river turns the system into being unsustainable to the biota. The present study synthesises the available information on the changes of its geological, geomorphological and ecological aspects and suggests some remedial measures to be adopted now and in future.

Agriculture↗

PubMed2004

[Survival of patients with aggressive non-hodgkin's lymphoma: no difference between first line treatment in a prospective randomised phase III clinical trial and first line treatment according to routine clinical practice].

OBJECTIVE: To compare survival of patients with disseminated aggressive non-Hodgkin's lymphoma (NHL) who were treated either as part of a clinical trial or in routine clinical practice. DESIGN: Retrospective. METHOD: The survival was studied of patients with disseminated NHL of an intermediate or high degree of malignancy who were treated in the Meander Medical Centre, Amersfoort, the Netherlands, in the years 1994-2001 with chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP). This took place either in routine clinical practice (RCP) or as part of a clinical trial where patients < or = 60 years of age received intensified CHOP and patients > 60 years received CHOP with growth factors. Treatment data, the response to therapy, survival and prognostic factors according to the International Prognostic Index for aggressive NHL were collected by a review of the patient records. RESULTS: Fifty-nine patients were eligible for this analysis: 32 men and 27 women with a median age of 63 years (range 30-83). Of these, 35 were treated within a clinical trial and 24 were treated in RCP. The patient characteristics in the two groups were comparable. There was no difference in median survival between the trial and RCP groups, this being 27 months for all patients, 34 months for the younger patients, 20 months for the elderly patients, and 42 months for patients who achieved complete remission following chemotherapy. CONCLUSION: No difference in overall survival was found between patients with disseminated aggressive NHL who underwent treatment according to either RCP or as part of a clinical trial. It demonstrates that both patients in clinical trials and patients treated according to RCP received equally effective therapy. Recent developments in NHL treatments are promising, and therefore participation in clinical trials should be encouraged.

Adult↗

PubMed2003

Water environmental planning considering the influence of non-linear characteristics.

In practical water environmental planning, the influence of the non-linear characteristics on the benefit of environmental investment was seldom taken into consideration. This paper demonstrates that there exist a lot of non-linear behaviors in water environment by emphatically analyzing the influence of the non-linear characteristics of the economic scale, the meandering river and the model on water environmental planning, which will make a certain impact on the water environmental planning that sometimes cannot be neglected. This paper also preliminarily explores how to integrate the non-linear characteristics into water environmental planning. The results showed that compared with traditional methods, water environmental planning considering non-linear characteristics has its prevalence and it is necessary to develop the relevant planning theories and methods.

China↗

PubMed2004

Numerical model of flow and pollutant transportation in non-orthogonal curvilinear coordinates.

The planar 2D k-epsilon double equations' turbulence model was adopted and transformed into non-orthogonal curvilinear coordinates. The concentration convection-diffusion was introduced to planar 2D SIMPLEC algorithm of flow in non-orthogonal curvilinear coordinates. The numerical model of pollutant transportation in non-orthogonal curvilinear coordinates was constructed. The model was applied to simulate the flow and pollutant concentration fields. In the testing concentration field, two optimal operations of contamination discharging both along bank and in the centerline at the first bend of the meandering channel were adopted. Comparison with available data showed the model developed was successful, was valuable to engineering application.

Algorithms↗

PubMed1992

A lifetime's love affair with antibody formation.

Professor Hans Gerhard Schwick has devoted the whole of his working life to Behringwerke, the world-renowned firm that owes its origins to Emil von Behring, the discoverer of antibodies. Schwick, like myself, has witnessed the incredible flowering of immunology during his career. He, like myself, has continued to see antibodies and immunity at the very centre of the extraordinary revolution in biology that will be seen by historians as perhaps the signal accomplishment of the last quarter of the 20th century. To give honour to such a man is easy; to know best how to do it is difficult. Therefore, I have chosen to attempt a personal odyssey--to describe my lifetime's love affair with the problem of antibody formation. This paper is in no sense any kind of history of the solution of the antibody puzzle. Rather, it is a description of one person's meandering pathway through the maze, a person who, like Professor Schwick, has been an eyewitness to history. Its intention is not self-indulgence, but a tribute to a man who has been an adornment to the scientific profession.

Animals↗

PubMed2001

Development of river ecosystem models for Flemish watercourses: case studies in the Zwalm river basin.

Only recently, modelling has been accepted as an interesting and powerful tool to support river quality assessment and management. The 'River Invertebrate Prediction and Classification System' (RIVPACS), based on statistical modelling, was one of the first and best known systems in this context. RIVPACS was developed to classify macroinvertebrate community types and to predict the fauna expected to occur in different types of watercourses, based on a small number of environmental variables. The prediction is essentially a static 'target' of the fauna to be expected at a site with stated environmental features, in the absence of environmental stress. Therefore this system is rather limited to apply in river assessment and management. Models that offer a prediction of faunal responses to changes in environmental features (e.g. changes in discharge regime, dissolved oxygen level, ...) would be of considerable value for river management. In this context, models based on classification trees, artificial neural networks and fuzzy logic were developed and applied to predict macro-invertebrate communities in the Zwalm river basin located in Flanders, Belgium. Structural characteristics (meandering, substrate type, flow velocity, ...) and physical-chemical variables (dissolved oxygen, pH, ...) were used as inputs to predict the presence or absence of macroinvertebrate taxa in the headwaters and brooks of the Zwalm river basin. In total, data from 60 measurement sites were available. Reliability and particular strengths and weaknesses of these techniques were compared and evaluated. Classification trees performed in general well to predict the absence or presence of the different macroinvertebrate taxa and allowed also to deduct general relations from the dataset. Models based on artificial neural networks (ANNS) were also good in predicting the macroinvertebrate communities at the different sites. Sensitivity analyses related to ANNs allowed to study the impact of the input variables on the presence or absence of macroinvertebrate taxa and to determine the major variables that affect the ecosystem quality and should be taken under direct consideration in the management of river basins. Performance of the fuzzy logic models was significantly related to the methods that were used to set up the membership functions and the reliability of the information that was available. Fuzzy logic did not perform as well as the other two techniques with regard to short term predictions. Fuzzy logic appeared to be better and more robust for long term predictions, because of the easy and pragmatic integration of general expert knowledge and data derived rules in the transparent inference engine. The overall conclusion of our study is that all three techniques, classification trees, artificial neural networks and fuzzy logic appeared to be reliable to predict macroinvertebrate communities in polluted streams.

Animals↗

PubMed2005

[The map of superficial lymphatic system of the breast and relation to the sentinel lymph node].

AIM: The aim of study was to topographically map the superficial lymphatic drainage of the breast and its relation to sentinel node. DESIGN: Anatomical study. SETTING: Department of Oncogynecology, Clinic of Obstetric and Gynecology of 1st Medical Faculty of Charles University and General Hospital, Prague. METHODS: The study was performed on 19 female cadavers. After slow intradermal administration of Patent Blau into the periareolar region, into the centers and into the borders of the individual quadrants of the breast, the lymphatics were visualized and a careful resection of these lymphatics and lymph nodes was performed. The lymphatics were drawn onto a schematic map of the breast on a transparent sheet and afterwards a summation of all schematic maps was performed. A map of the lymphatic vessels of the breast was based on this summation. RESULTS: After subcutaneous administration of patent blue were clearly visualized the subareolar plexus and draining sentinel node in the axilla, as well as one or two supplying lymphatics. Despite great variability in the lymphatic drainage of the breast, it was demonstrated that the natural dominant drainage for the outflow of lymph from the superficial areas of the breast are the axillary nodes. CONCLUSION: From the course of the lymphatic vessels it is evident that the breast cannot be divided into functionally separate segments. According to the lymphatic map of the breast, one can assume that in carcinoma of the breast it is the lymphatic drainage and not the localization of the tumor that plays a primary role in the development of metastases. One cannot ignore the existence of alternative drainage pathways of the breast, but their role in the beginning of dissemination of tumor cells in comparison with the axilla is negligible. Subdermal administration of Patent Blau is a reliable and effective method of visualizing lymphatic vessels and the draining lymph nodes of the breast. Due to the meandering course of lymphatics in the breast, we cannot understimate the role of radiation therapy after breast conserving surgery.

Aged↗

PubMedDate not supplied

Nailfold capillaroscopic findings in primary Sjögren's syndrome: clinical and serological correlations.

OBJECTIVE: To describe the capillaroscopic abnormalities observed in patients with primary Sjögren's Syndrome (pSS), associating them with clinical and serologic features, and comparing these findings to those observed in normal controls. METHODS: Sixty-one consecutive patients with pSS were studied by clinical evaluation, serology, and nailfold capillary microscopy (NCM). Twenty-one normal controls were also examined. Capillaroscopic findings were recorded in a standardized way by a blinded observer Capillary loss on NCM was evaluated using a deletion score. RESULTS: NCM was normal in 59.0% of pSS patients; 29.5% had non-specific abnormalities, and 11.5% presented a SD-like pattern. Patients presented a higher deletion score than controls (p < 0.001). Other capillaroscopic parameters (number of dilated, bizarre, and meandering capillaries; capillary hemorrhages; venous plexus visibility) did not differ significantly between patients and controls. Among patients, the deletion score was higher in those with systemic manifestations (p = 0.022) and Raynaud's phenomenon (p = 0.050). No association between the presence of antinuclear antibodies, rheumatoid factor, anti-SSA/Ro and anti-SSB/La with qualitative or quantitative NCM findings was found. Among the 7 patients with SD-like pattern on NCM, 6 had Raynaud's phenomenon, but only 2 presented autoantibodies related to systemic sclerosis (1 with anticentromere and 1 with low titer antitopoisomerase I). None of these patients met the ACR criteria for SSc. CONCLUSIONS: SD-like pattern on NCM is observed in a small but significant proportion of pSS patients. The association of systemic involvement with a higher deletion score may be related to the hypothesis that these manifestations represent clinical expressions of systemic vasculitis.

Adult↗

PubMed1991

[A case of bronchial artery aneurysm demonstrating a mass shadow on chest X-ray film].

A 66-year-old woman was admitted on May 13, 1989, because of an abnormal round shadow in the right hilum on chest X-ray film. Bronchoscopy revealed a stenosis of the right B8 caused by a bulging lesion. An aortogram showed a large meandering bronchial artery and a saccular aneurysm. The aneurysm was about 25 mm in diameter and associated with a bronchopulmonary anastomosis. It was surgically removed by right lower lobectomy. Pathological examination proved that the resected lesion was an arterial aneurysm. Patchy arteriosclerotic change was present in the intima of the aneurysm, but there was no evidence of inflammatory change in the arterial wall and the adjacent alveoli and bronchi. Twenty-six cases of bronchial artery aneurysm have been previously reported in the literature, but this is the first case that appeared as a solitary nodule on conventional chest X-ray.

Aneurysm↗

PubMed1991

Alterations of the nailfold capillary morphology associated with Raynaud phenomenon in patients with systemic lupus erythematosus.

Quantitative analysis of nailfold capillary morphology was performed in age and sex matched groups of 29 patients with systemic lupus erythematosus (SLE) presenting Raynaud phenomenon (RP), 29 RP negative patients with SLE with the same duration of the disease, and 29 healthy controls. Percentages of tortuous, meandering and bushy capillaries were significantly increased in both groups of patients without influence of RP. Capillary density was lower, mean diameters of the capillary loops were higher in patients, especially when RP was present (at the venular branch in microns, mean +/- SD: controls: 15.0 +/- 2.0, RP negative patients with SLE: 17.6 +/- 3.6, RP positive patients with SLE: 20.5 +/- 6.3). In a subgroup of 13 patients with frequent Raynaud's attacks (more than 1/week), diameters were still higher (22.1 +/- 7.1, p to controls less than 0.0005; p to RP negative patients less than 0.05). In patients with SLE, the prevalence of RP seems not to be associated with the increased number of abnormal capillaries but with capillary enlargement, correlating with the frequency of attacks.

Adult↗

PubMed1991

[Coronary artery bypass grafting for ischemic heart disease combined with aortitis].

Coronary artery bypass grafting (CABG) was performed in a 67-year-old woman with aortitis. She had a past history of right radical mastectomy. Preoperative coronary angiogram showed diffuse stenotic lesions in both right and left coronary arteries. The pressure gradient between ascending aorta and peripheral radial artery was 90 mmHg and the cause of coronary stenosis seemed to be hypertension due to stenotic distal aorta. The aortogram showed occluded bilateral internal thoracic arteries (ITA) and stenotic abdominal aorta. The cephalic artery was supplied by a large meandering artery via dilated gastroepiploic artery (GEA). And thus the GEA was not useful for CABG. Quadruple CABG was performed with mild varicose saphenous vein (saphenous vein grafts to left anterior descending artery and third branch, and sequential saphenous vein graft to right posterior descending and atrioventricular branches). It seemed to be important to demonstrate the arterial lesion of ITA and GEA before CABG in patients with aortitis.

Aged↗

PubMed1988

Incorporation of argyrophilic proteins into the nucleolus-associated chromatin caused by exposure to actinomycin D.

The nucleolus-associated chromatin (NAC) became argyrophilic when the root tips of Vicia faba were treated with 0.2 microgram/ml actinomycin D (AMD) for 15 hr at 22 degrees C. To determine how the argyrophilic NAC is formed, detailed observations were carried out on thin sections following silver staining and ribonucleoprotein (RNP) preferential staining. In a few instances, thick channels with loosely packed fibrillar material (light fibrillar area) were seen meandering throughout the nucleoli. Large granules 280-330 A in diameter (300 A granules), which responded positively to both RNP preferential staining and silver staining, were sometimes present within the light fibrillar area. Some fragments of NAC were also seen in the light fibrillar area and, interestingly, they responded positively to silver even though they were bleached by the RNP preferential staining. Most nucleoli showed a segregation of two major components, the fibrillar and granular components. The nucleolar vacuoles were localized strictly within the fibrillar component and usually accompanied the light fibrillar area or, alternatively, contained a number of 300 A granules. Another category was characterized by the presence of poorly developed vacuoles in which the 300 A granules were still found, and the spherical argyrophilic NAC associated with the surface of the nucleolus. The present observations suggest that AMD induces the DNA-containing structure engaged in ribosomal RNA transcription to condense, and during this process some argyrophilic proteins are incorporated into the chromosomal structure thereby causing the NAC to become argyrophilic. In this context, the NAC is assumed to contain ribosomal RNA genes.

Cell Nucleolus↗