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At least 235 records · Page 13Linked to original sources
PubMed2001

Significant changes in systolic blood pressure post vectored upper cervical adjustment vs resting control groups: a possible effect of the cervicosympathetic and/or pressor reflex.

OBJECTIVE: To determine whether a vectored adjustment of the atlas in patients identified as demonstrating signs of upper cervical joint dysfunction would cause lowering of blood pressure in comparison with resting controls. DESIGN: Test 1: controlled clinical trial with a treatment (adjustment) group and a control (resting) group. Test 2: controlled clinical trial with subjects serving as their own controls. SETTING: Private chiropractic practice. PARTICIPANTS: Test 1: Forty established patients demonstrating signs of upper cervical subluxation/joint dysfunction and 40 established patients without such signs. Test 2: Thirty established patients demonstrating signs of upper cervical subluxation/joint dysfunction. INTERVENTION: Specific, vectored upper cervical (atlas) adjustment or similarly positioned resting. MAIN OUTCOME MEASURES: Prerest, postrest, and postadjustment systolic, diastolic, and pulse rates as recorded through use of a digital oscillometric sphygmomanometer. RESULTS: In test 1, subjects receiving adjustment had a significant (P <.001) decrease in systolic blood pressure whereas resting subjects did not. Intergroup comparison of the treatment (adjustment) and control (resting) groups demonstrated a significant difference (P <.001). A greater pre/post drop in systolic pressure was associated with greater age and higher initial systolic pressure. In test 2, the pre/postrest change in systolic blood pressure was not significant. The systolic blood pressure changed significantly (P <.001) from postrest readings to postadjustment readings. CONCLUSION: The results indicate that palpation and vectored atlas adjustment causes a significant decrease in systolic blood pressure in patients with putative upper cervical subluxation/joint dysfunction in comparison with resting controls. Similar results were also demonstrated when subjects acted as their own controls. The lack of randomization, blinding, and a manipulated control group are factors that weaken these findings. The sudden drop in systolic pressure is proposed to be due to stimulation of the cervicosympathetic reflex or moderation of muscle tone and elimination of the effects of the pressor reflex.

Adult↗
PubMedDate not supplied

Placental pathology in women with type 1 diabetes and in a control group with normal and large-for-gestational-age infants.

Unexplained intra-uterine fetal death is still a problem in diabetic pregnancies, especially in those with an LGA-infant. We hypothesized that in these pregnancies impaired placental function, in terms of abnormal placental weight and/or abnormal placental histology, may account for this phenomenon. To test this hypothesis, we assessed the relative placental weight and scored several histological abnormalities in 34 AGA- and 24 LGA-placentae of type 1 diabetic women and in 22 AGA- and 16 LGA-placentae of control women. Relative placental weight was comparable in the LGA-diabetic cases and in the control groups, but was significantly higher in the AGA-diabetic subgroup. Histological abnormalities such as the presence of nucleated fetal red blood cells, fibrinoid necrosis, villous immaturity and chorangiosis were observed more often in the diabetic placentae compared with the control placentae. These differences in histology were particularly observed when we compared both AGA-groups. LGA-control placentae showed a high incidence of histological abnormalities, almost comparable to the diabetic placentae. Only fibrinoid necrosis was significantly more common in the LGA-diabetic placentae. Three of the four cases of perinatal death/asphyxia in the diabetic group concerned an LGA-infant with a relative low placental weight. In conclusion, placentae of women with type 1 diabetes showed several abnormalities that can be associated with impaired functioning. The difference between AGA- and LGA-diabetic placentae was related to relative placental weight and our data suggest that an increase in relative weight may protect the fetus from asphyxia. Placentae from LGA-non-diabetic women showed several similarities to those of women with diabetes.

Adult↗
PubMed1979

[The hand in diabetes. Study of 97 diabetics compared to a control group].

To determine whether there is hand involvement specific to diabetes, 97 diabetics were compared with the same number of matched controls. Hands were examined with particular emphasis on skin, intrinsic muscles, articular mobility, sense of touch and vibration, digital systolic pressure, and radiological analysis of bones and joints. The most significant involvement, clearly present in 7 cases and less specifically in 12 other diabetics, included all of the following: atrophy and weakness of intrinsic muscles, painful interphalangeal rigidity limiting extension or flexion of the fingers, periarticular swelling of the phalanges, and trophic changes of the skin. Separately, these changes are not specific to diabetes: in the control group, although less frequent, they were found in patients aged 60 and over and are considered to be signs of senescence. Diabetes apparently accelerates the process of aging. Diabetic changes in the hand appear to be facilitated by neuropathy but not by arterial involvement. X-ray revealed a higher incidence of osteopenia and above all of vascular calcifications in the diabetic.

Adult↗
PubMed1975

Effect of rising intragastric pH induced by several antacids on serum gastrin concentrations in duodenal ulcer patients and in a control group.

The interrelationship of the effects of antacids and of rising intragastric pH on serum gastrin levels was examined by comparing the effect of three antacids (Mg(OH)2Al(OH)3, and CaCO3), and their nonbuffering chloride compounds (MgCl2, AlCl3, and CaCl2), on serum gastrin and intragastric pH in duodenal ulcer patients. In the case of calcium, the effect of CaCl2 with a pH of 10, and in another group, CaCl2 with a pH of 2, was studied. In the case of magnesium, a control group was also investigated. In another group, the effect of a nonionized suspension (BaSO4) was studied in order to assess the contribution of intragastric volume. Serum gastrin was determined radioimmunologically, and pH measurements were performed in vitro using a glass electrode. Serum gastrin concentrations rose significantly whenever intragastric pH was raised. Serum gastrin also rose after MgCl2, AlCl3, and CaCl2 with a pH of 2, when intragastric pH was not significantly altered. This rise, however, was significantly smaller than after administration of the antacids, except in the MgCl2-Mg(OH)2 and in the CaCl2 pH 10-CaCO3 groups. No significant rise of serum gastrin levels was observed after BaSO4. In nonulcer subjects, gastrin response was smaller than in the duodenal ulcer patients. The results suggest that administration of nonbuffering Mg-, Al-, and Ca-chlorides leads to elevated serum gastrin levels in duodenal ulcer patients; rising intragastric pH, however, exerts an additional serum gastrin response.

Adult↗
PubMed1989

Morphological changes of the ovarian surface epithelium in women with ovarian polycystic disease or endometrial carcinoma and a control group.

The ovarian surface epithelium and that of related inclusion cysts were studied in 50 women with ovarian polycystic disease and they were compared with our preceding observations performed on women with endometrial carcinoma (n = 50) and on women without any hyperplastic or neoplastic genital tract pathology (n = 50). In 16 women (32%) the ovarian epithelium with normal aspect was found on the surface of the ovary and in inclusion cysts. In the remaining 34 women (68%) surface papillomatosis, hyperplastic and metaplastic changes were present on the ovarian surface and/or in the inclusion cysts. These findings were similar to those observed in the group of women with endometrial adenocarcinoma, while the surface epithelium was often normal in the control group. Our observations confirm the hypothesis of a hormonal influence in the hyperplastic and metaplastic modifications of the ovarian epithelium and in the related common epithelial tumors of the ovary.

Adult↗
PubMedDate not supplied

[Stroke - the role of hyperlipoproteinemia. I. Lipid metabolism and various arteriosclerosis risk factors in a control group].

On the basis of a study of 218 control subjects in 10-year age groups the authors determined the mean levels and critical values of certain serum lipid components (cholesterol, triglycerides, beta-lipoproteins, esterified fatty acids and total lipids). Forty-two subjects were isolated (11.2%) with hyperlipoproteinaemia. Other atherosclerosis risk factors were determined in them as well. Hypertension was found in 19%, diabetes in 7%, obesity in 14%, smoking in 43%. The authors discuss the criteria qualifying the patients to the control group in the studies on lipid metabolism.

Adolescent↗
PubMed1994

Prevalence of panic disorder in mitral valve prolapse: a comparative study with a cardiac control group.

This study investigated the relationship between mitral valve prolapse (MVP) and panic disorder (PD), by comparing the prevalence of PD in 33 patients with MVP and 27 patients with haemodynamically insignificant atrial septal defect or patent ductus arteriosus. MVP was diagnosed using standard echocardiographic criteria and the presence of mental disorder was assessed blindly with the help of the Schedule for Affective Disorders and Schizophrenia. DSM-III criteria were used to diagnose PD. The two groups did not differ in age and sex; 12.1% of MVP patients and 3.7% of cardiac controls had PD (NS). Although the prevalence of PD in our sample of MVP patients was considerably higher than the prevalence of PD in the general population, this need not necessarily indicate a causal relationship between MVP and PD and may be due to studying a hospital-based sample. The absence of any significant difference in prevalence of PD between MVP patients and a carefully selected cardiac control group drawn from the same setting argues against any special relationship between PD and MVP.

Adult↗
PubMed1991

[The effect of adhesive agents on the bonding strength of ceramic-composite. An in-vitro comparative study with 6 "porcelain primers" and a control group].

Orthodontic brackets were bonded to a total of 240 Biodent porcelain surfaces pretreated with a number of different porcelain primers. In a control group, 40 surfaces were pumiced, etched, rinsed and dried, and then bonded to similar brackets without the use of a primer. The test objects of group 1 (n = 140) and those of group 2 (n = 40) were tested for bond shearing strength in a material testing machine (Zwick 1441) after prior incubation in a corrosive fluid at a pH of 2.3 and a temperature of 37 degrees C for 24 hours and 21 days, respectively. The fracture sites were inspected and analysed. Incubation in corrosive fluid reduces the strength of the porcelain-composite bonding, the shearing strength and the number of fractures in the bonding decreasing. Damage to the porcelain was seen to occur after the use of Lee-Ortho-Prime and Bond-Por primers. All the primers tested can be used, although a bond shearing strength of less than 2 N/mm2 is at the lower limit of what can be accepted under the usual conditions of daily practice.

Ceramics↗
PubMed1992

A Piagetian framework as a basis for the assessment of cognitive organization in schizophrenia: a comparison of adolescent and adult patients to a normal control group.

Piaget's theoretical framework was utilized in this study to investigate the cognitive organization of schizophrenic patients. Data from a battery of eight Piagetian tasks of concrete and formal operations was collected for adolescent and adult-acute and chronic schizophrenic patients, and was compared to matched normal control groups. Findings show significant differences between patients and controls; among the patients' chronicity, age and hospitalization are contributing variables to lower cognitive performance. Concrete operational tasks in the physical and spatial domains are retained better than in the logico-mathematical domain, or formal operational tasks in all domains. Major problems appear in the ability to abstract general criteria and to mentally work with more than one dimension at a time. A logical approach to the solution of concrete problems and solving problems which seem to present a contradiction, or cause problems in the accommodation and integration of one's thinking. Further studies are needed in order to draw conclusions and to understand the implications for every day functioning, deficient in the schizophrenic patient.

Acute Disease↗
PubMed1992

An examination of the role of female hormones and pregnancy as risk factors for rheumatoid arthritis, using a male population as control group.

While being female is known to increase the risk of developing rheumatoid arthritis approximately threefold, this study, by making use of a male control group, suggests that female sex hormones per se are unlikely to be the main cause of this discrepancy. Apart from the teens, when rheumatoid disease is extremely rare in males, the female/male incidence ratio remains almost constant throughout the adult age range, in spite of the reduction in endogenous oestrogen levels at the menopause. Pregnancy is known to ameliorate RA, but this study found that it was also the most common identifiable event preceding the onset of RA in women of childbearing age (22%), which may explain the apparent protective role of oral contraceptives in this age group.

Adult↗
PubMed1994

An epidemiological study of hand eczema. II. Prevalence of atopic diathesis in hairdressers, compared with a control group of teachers.

The aim of this cross-sectional study was to estimate the prevalence of atopic dermatitis in hairdressers compared with a control group of elementary school teachers. Both groups consisted of employees who reported exanthema on the hands and/or forearms at the time of completing a questionnaire. The mean age for the affected hairdressers was 26 years (range: 17-63) and for the teachers 44 years (range: 28-65). The mean duration of employment was 85 months for the hairdressers (range: 2-552) and 177 months for the teachers (range: 24-360). The frequency of atopic dermatitis was 12.7% (C.I.: 6.3-19.2) in the group of hairdressers and 25% (C.I.: 7.7-42.3) in the group of teachers. No difference was observed between the groups regarding atopic mucosal symptoms or familial atopy.

Adolescent↗
PubMed1994

An epidemiological study of hand eczema. IV. Degree and pattern of eczema in affected hairdressers, with and without atopic symptoms, compared with a control group of affected teachers.

The aim of this study was to show degree and pattern of hand eczema in affected hairdressers (n = 69), compared with a control group of teachers (n = 19). Both groups consisted of employees having eczema, confirmed by the visit of a doctor at the working place. The mean age for the affected hairdressers was 27 years (range: 17-63) and for the teachers 43 years (range: 27-57). The mean duration of employment was 96 months for the hairdressers (range: 2-552) and 182 months for the teachers (range: 25-336). The localization of eczematous lesions, presence of efflorescenses and extent of skin affection were recorded by constructing scores for these variables. The mean number of localizations was significantly higher in hairdressers than in teachers; this was caused by greater affection of fingers in hairdressers compared to teachers. Seventy-five percent of the hairdressers and 79% of the teachers had only modest or very moderate erythema. Fourteen percent and 5%, respectively, had vesicular dermatitis. The right upper limb was most affected in both hairdressers and teachers. Three subgroups of hairdressers were considered: hairdressers with atopic dermatitis, those with only atopic mucosal symptoms and those without atopic symptoms. No significant differences were found between these groups, except a significant higher finger involvement in atopics compared to non-atopics.

Adolescent↗
PubMed2005

Reproducibility of nitrate-stimulated tilt testing in patients with suspected vasovagal syncope and a healthy control group.

OBJECTIVE: Nitrate-stimulated tilt testing may be used to diagnose vasovagal syncope or to guide therapy. To date, the reproducibility of the test in patients with clinically suspected vasovagal syncope and healthy controls is undetermined. A high reproducibility is a prerequisite for correct interpretation of the test result. This study investigates the reproducibility of a nitrate-stimulated tilt test in patients with clinically suspected vasovagal syncope and a healthy control group. METHODS AND RESULTS: We studied 43 patients (24 women, 19 men) with a typical history of vasovagal syncope and 18 healthy controls (3 women, 15 men). We used a combined tilt protocol with a 30-minute passive and 15-minute nitrate-stimulated phase. The second tilt test was performed 16 +/- 12 days after the first. In both patients and controls, overall positive tilt responses were reproduced in the second test in 100%. In contrast to this, the reproducibility of an overall negative test was 50% in patients but 93% in controls. Overall hemodynamic responses to tilt were reproducible in 80%. CONCLUSION: Nitrate-stimulated tilt testing in both patients with suspected vasovagal syncope and controls has an excellent reproducibility of positive results but a moderate reproducibility of negative results. Importantly, these results are still valid at a repeat interval of 2 weeks and longer. These data suggest that in patients with suspected vasovagal syncope, a nitrate-stimulated tilt test may provide a suitable tool to evaluate the efficacy of a therapeutic approach.

Adolescent↗
PubMed1987

Spontaneous tumors in F344/DuCrj rats from 12 control groups of chronic and oncogenicity studies.

The types and incidences of spontaneous tumors in F344/DuCrj rats were examined in 960 males and 959 females served as the control groups of separate twelve 2-year chronic and oncogenicity studies carried out during a 1978-1983 period. The major tumors occurred at more than 5% incidence were leukemia (mononuclear cell), testicular interstitial cell tumor, preputial gland adenoma, pituitary anterior adenoma, thyroid C-cell adenoma, adrenal pheochromocytoma and subcutis fibroma for males, and leukemia, uterine endometrial polyp, pituitary anterior adenoma, thyroid C-cell adenoma and mammary gland adenoma/fibroadenoma in females. Analyses on age-related occurrence of tumors revealed that the incidences of most of the major tumors in males attained already to the plateau between 85 and 97 weeks of age while those in females showed a steep rise during the last interval of observation, 98 to 110 weeks of age. An intralaboratory heterogeneity in incidence was observed in the thyroid C-cell adenoma and the adrenal pheochromocytoma for males, and the anterior pituitary adenoma for females.

Adrenal Gland Neoplasms↗
PubMed1987

Articular chondrocalcinosis in seropositive rheumatoid arthritis. Comparison with a control group.

The prevalence of articular chondrocalcinosis was studied in a group of 100 patients with seropositive rheumatoid arthritis (RA). Articular chondrocalcinosis was observed less frequently (3%) than in a control group (19%) of 221 age and sex matched patients with low back pain or extraarticular rheumatism. This difference is statistically significant (p less than 0.001). Articular chondrocalcinosis occurred in the older patients with RA, and was observed in those with the shortest duration of the disease.

Adolescent↗