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Costs of gastrointestinal examinations: a comparative study.

The costs of performing four major gastrointestinal examinations were studied and compared: single-contrast and double-contrast upper gastrointestinal series, and single-contrast and double contrast barium enema. A total of 1,725 examination records were reviewed for the number of films expended, room occupancy time, and physician involvement time, and the costs of the studies determined. The data indicated a large and significantly increased time and expense required for the double-contrast barium enema over the single-contrast barium enema. A relatively small increment was found in the cost performing the double-contrast upper gastrointestinal series over the single-contrast study.

Barium Sulfate

Characterization of the molecular components in kinetoplast-mitochondrial DNA of Trypanosoma equiperdum. Comparative study of the dyskinetoplastic and wild strains.

The structure of the kinetoplast DNA of Trypanosoma equiperdum has been studied and compared to the structure of the circular mitochondrial DNA extracted from a dyskinetoplastic strain of T. equiperdum. In T. equiperdum wild type, the kinetoplast DNA constitutes approximately 6% of the total cellular DNA and is composed of approximately 3,000 supercoiled minicircles of 6.4 x 10(5) daltons and approximately 50 circular supercoiled molecules of 15.4 x 10(6) daltons topologically interlocked; The buoyant density in CsCl of the minicircles is 1.691 g/cm 3. The large circles have a buoyant density of 1.684 g/cm 3, are homogeneous in size and are selectively cleaved by several restriction endonucleases which do not cleave the minicircles. The cleavage sites of six different restriction endonucleases have been mapped on the large circle. The minicircles are cleaved by two other restriction endonucleases, and their cleavage sites have been mapped. The mitochondrial DNA extracted from the dyskinetoplastic strain of T. equiperdum represents 7% of the total DNA of the cell and is composed of supercoiled circles, heterogeneous in size, and topologically associated in catenated oligomers. Its buoyant density in CsCl is 1.688 g/cm 3. These molecules are not cleaved by any of the eight restriction endonucleases tested. The reassociation kinetics of in vitro labeled kDNA minicircles and large circles has been studied. The results indicate that the minicircles as well as the large circles are homogeneous in sequence and that the circular DNA of the dyskinetoplastic strain has no sequence in common with the kDNA of the wild strain.

Animals

Robotic-assisted transbronchial biopsy versus computed tomography-guided transthoracic needle biopsy for peripheral pulmonary lesions: a systematic review and meta-analysis of direct comparative studies.

Robotic-assisted bronchoscopy (RAB) and computed tomography-guided transthoracic biopsy (CTTB) are competing strategies for sampling peripheral pulmonary lesions (PPLs). Whether they differ in yield or safety is uncertain. To our knowledge, this is the first systematic review restricted to direct comparisons. We searched MEDLINE, Europe PMC, Scopus, Web of Science and ClinicalTrials.gov from inception to 7 July 2026 for studies directly comparing RAB with CTTB in adults with PPLs. The primary outcome was strict 2024 American Thoracic Society/American College of Chest Physicians diagnostic yield. Risk of bias was assessed with ROBINS-I and certainty with GRADE. A cohort-genealogy step identified, per outcome, the largest set of cohorts sharing no patients; only that set was pooled, with Hartung-Knapp and Mantel-Haenszel sensitivity analyses. Five retrospective studies from one US health system were eligible. Four share patients; at most three cohorts are mutually independent. Across those three, diagnostic yield was comparable (risk ratio [RR] 0.99, 95% confidence interval [CI] 0.93-1.06; I²=24%; Hartung-Knapp 0.87-1.13), with an identical relative effect under strict and intermediate definitions although absolute yields fell from 88% to 74-84% under strict criteria. Pneumothorax requiring a chest tube and/or admission was about three-quarters less frequent with RAB across all three cohorts (RR 0.25, 95% CI 0.14-0.46; I²=0%; Hartung-Knapp 0.07-0.96). Strict yield (RR 0.99) and any pneumothorax (RR 0.06) were reported by two cohorts each and neither survives the few-studies correction. RAB took about 50 min longer than CTTB where same-session staging endobronchial ultrasound was counted in the robotic time, but only about 8 min longer than CTTB where it was not. Only one cohort reported yield by lesion size category and none reported yield by bronchus sign or lung zone, so lesion-level subgroups could not be pooled. Certainty was low for pleural complications and very low elsewhere. Low-certainty evidence indicates that RAB is associated with fewer pleural complications, with no statistically detectable difference in diagnostic yield; equivalence was not formally established. Because all evidence is retrospective, confined to one health system, and almost never stratified by lesion size or accessibility, these findings are hypothesis-generating and require a multicenter randomized trial.

Humans

Lymphocyte studies in rheumatoid arthritis. III. A comparative study of the responses of peripheral blood and synovial fluid lymphocytes to phytomitogens.

The response of peripheral blood and synovial fluid lymphocytes to three non-specific mitogens has been studied. The paired samples were taken from patients with a range of inflammatory arthritides. Unstimulated synovial fluid lymphocytes (SFL) tended to have a greater uptake of tritiated thymidine than had unstimulated peripheral blood lymphocytes (PBL). This background uptake of tritiated thymidine by SFL showed a positive correlation with the response these SFL then showed to the mitogens. A significant depression was observed in the SFL response to phytohaemagglutinin when compared with the paired PBL response; this was seen in both the rheumatoid arthritis and other inflammatory joint diseases groups. SFL responses to concanavalin A and pokeweed mitogen, although depressed in individual cases, failed to show a significant depression overall. Attempts to restore the SFL response to that of the paired PBL by removal of any possible blocking substance from the cell surface either by pre-incubation of SFL in tissue culture medium or by enzyme treatment were unsuccessful. This suggested that cell surface blockers were possibly not the reason for deficient SFL reponses and that other factors were involved.

Arthritis, Rheumatoid

[Experimental studies of various model materials. 1. Comparative study on linear dimension behavior].

The linear dimensional behaviour of the model materials Begolith, Dentaloc, Tewestone, Impredur and Keramik-Cement was investigated at various mixing temperature, the thickness of layer ranging from 3 to 5 mm. It seems that the model materials Begolith, Dentaloc and Tewestone will yield good results in practice. Impredur may be recommended on certain conditions. On the contrary, Keramik-Cement is not suited as a model material.

Dental Materials

Studies on pancreatic duct system. II Comparative study of histological features, and three-dimensional reconstruction of pancreatic ducts.

Three-dimensional reconstruction of pancreatic ducts were made from specimens of pancreases from chronic pancreatic injury dogs following adjuvant injection, one patient with chronic non-alcoholic pancreatitis, and 2 patients with chronic alcoholic pancreatitis. The ductal alterations of alcoholic pancreatitis showed more apparent changes than those of non-alcoholic pancreatitis. The lesions in experiment such as uneven surface, irregular dilatation, tortuosity, and anastomosis, resembled to those of alocholic calcifying pancreatitis. Although gross appearance of the reconstructed ducts in advanced cases of experimental pancreatic injury revealed some resemblance to that of alcoholic calcifying pancreatitis, histologically, the epithelial changes of the former were different from those of the latter. Thus we concluded that more complicated factors than those considered in experiment play a role in combination in the pathogenesis of bead-like dilatation of the pancreatic ducts of chronic pancreatitis.

Alcoholism

Studies on bovine leucosis V. A comparative study on the practical value of the agar gel immunodiffusion test, the indirect fluorescent antibody technique and the micro complement fixation test for the detection of antibodies to bovine leucosis virus.

The practical value of the indirect fluorescent antibody technique (I FAT), the micro complement fixation test (M CFT) and the agar gel immunodiffusion test (AGIDT) for the detection of antibodies to bovine leucosis virus (BLV) was investigated. For this purpose 1495 serum samples were examined. There was a remarkably good agreement between the three tests in the demonstration of antibodies to BLV especially if sera with a sufficient high concentration of antibodies ("late serum") were under investigation. These positive sera were derived only from farms which exploited one or more imported animals. A disagreement of results of the three tests was observed in 38 (2.5%) cases. This was due to: (1) difficulties in reading of the test; (2) presumably by the demonstration of different classes of antibody and (3) the fact that in the AGIDT sera could be used undiluted. This discrepancy was especially evident with sera with a low concentration of antibodies ("early or incubation sera"). A drawback for the M CFT is the anticomplementary activity found in 17% of the bovine serum samples.

Animals

Neuroradiology of ossification of the posterior longitudinal spinal ligament. Comparative studies with computer tomography.

Comparative neuroradiologic studies of the posterior longitudinal spinal ligament were performed in 15 cases showing myelopathy. On visualizing the ossified foci CT scan was found to be superior to the conventional roentgenograms, and detailed evaluation of the constricted spinal canal with related neurologic deficits became possible. CT analysis must be performed to differentiate spondylotic myelopathy, which is essential when considering operative intervention.

Humans

[Labor and delivery, fetal and maternal risk following cerclage. A comparative study (author's transl)].

In a comparative study of the course of pregnancy and delivery of 357 patients who delivered live infants between 1966-1976 following cerclage operation were compared to a control group of 380 without cerclage who were matched in age, parity and delivery time to the group under study. The high prematurity rate in the pregnancies preceeding the cerclage of 28.4% decreased following the cerclage to 16.8% (p less than 0.001). The perinatal mortality was reduced from 21.5% to 5.6% (p less than 0.001). This effect was especially achieved by the lower incidence of deliveries of infants with a birth weight of less than 1500 grams (p less than 0.05). The difference to the controls regarding prematurity (8.2%) and perinatal mortality (1.6%) remained significant (p less than 0.001). An increased rate of malformations in the cerclage children was not noticed. The maternal risk is low and consists mainly of a increase of cervical lacerations (4.9%) and problems of wound healing (2.2%). The duration of labor and type of delivery, the type of third stage of labor, and the post-partum course were not different from the control group.

Birth Weight

Amantadine in drug-induced extrapyramidal signs: a comparative study.

In our non-blind comparative study, amantadine was as effective as the standard medications, benztropine and ethopropazine, in controlling drug-induced extrapyramidal signs. However, statistically significant improvement was noted a week after all the three medications. In addition, extrapyramidal signs were not completely controlled in most patients even after weeks, even though substantial improvement was noted. This indicates the limitations of the currently available antiparkinsonian medications. Amantadine produced least side effects. Therefore, it may be particulary useful in patients who may not tolerate antiparkinsonian medication with anticholinergic properties. Our clinical finding that two patients with depression improved was rather interesting and needs further exploration. In summary, anamtadine is a valuable addition to our armamentarium of antiparkinsonian drugs. The drug compared favourably with other standard medications. The problem of dissipation of the therapeutic effects over time was not studied in our trial.

Adult

Levamisole in rheumatoid arthritis. A randomised double-blind study comparing two dosage regimens of levamisole with placebo. Multicentre study group.

The therapeutic effect of levamisole in patients with rheumatoid arthritis was evaluated in a sixteen-centre double-blind controlled study which compared continuous and intermittent levamisole treatment with placebo for six months. 363 patients with classic or definite rheumatoid arthritis and active disease were evaluated. Continuous and intermittent levamisole treatments were equally effective in controlling disease activity. 20% of patients had important drug-related adverse reactions. The results demonstrated that levamisole is an active drug in patients with rheumatoid arthritis.

Administration, Oral

Acoustic neuroma removal: a comparative study of translabyrinthine and suboccipital approaches.

A comparative study of the suboccipital and translabyrinthine approaches for acoustic neuroma removal in 91 cases using a otologic-neurosurgical team is presented. Fifty of these cases involved the suboccipital route using microsurgical techniques; the remaining cases involved the standard otologic routes. The same neurosurgeon participated in all 91 cases. Two otologists participated in the study. The results of our series of cases indicate that the suboccipital route is the procedure of choice for acoustic neuroma removal.

Ear, Inner

A comparative study of horseradish peroxidase conjugates prepared with a one-step and a two-step method.

In this study we compared horseradish peroxidase (HRP)-labeled rabbit antihuman immunoglobulin G (IgG) conjugates, prepared by a one-step and a two-step method. Glutaraldehyde was used as a cross-linking agent. Two methods were used for removing unconjugated HRP: Sephadex G-200 gel chromatography and ammonium sulfate precipitation. The conjugates were characterized immunologically, immunochemically and enzymatically. The immunohistoenzymic properties of the conjugates were tested on unfixed cryostat sections of the skin of patients with chronic discoid lupus erythematosus. The influence of the presence of unconjugated HRP and unconjugated IgG was studied. Optimal results were obtained with conjugates prepared by a two-step method. Removing unconjugated HRPimproved the immunohistoenzymic properties of the conjugates. Conjugated and unconjugated IgG could be separated by Sephadex G-200 gel chromatography.

Animals

A phase III study comparing the clinical utility of four regimens of 5-fluorouracil: a preliminary report.

A clinical trial involving 462 colon, rectum, and breast cancer patients randomized among four different dosage regimens of 5-FU (an intravenous loading course, a weekly intravenous schedule, a nontoxic schedule, and an oral schedule) has shown a significantly better response among colon-rectum cancer patients for the intravenous loading course. In addition, duration of response and time to progression are also significantly better. Overall survival is approaching significance for the colon rectum group (p value .082). In contrast, breast cancer patients show little difference between treatments. Toxicity is somewhat higher for the loading course.

Administration, Oral