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991.
To determine the optimal site for antegrade puncture of the femoral artery, the authors evaluated three cadaver specimens and computed tomographic (CT) scans of 50 patients. The relationships among the common femoral artery, the femoral artery bifurcation, the center of the femoral head, and the inguinal ligament were evaluated. CT showed that the center of the femoral head was always located caudal to the level of the inguinal ligament but cranial to the bifurcation of the common femoral artery. Therefore, the femoral head seems to provide a reliable landmark for entering the common femoral artery. 相似文献
992.
Acute cholecystitis: diagnostic accuracy of percutaneous aspiration of the gallbladder 总被引:1,自引:0,他引:1
Results of gallbladder bile aspiration and culture were correlated with presence or absence of acute cholecystitis in 36 patients to test the role of these procedures in hospitalized patients with sepsis. Diagnostic aspiration of the gallbladder was performed in 11 patients, and in the remaining patients a combination of percutaneous aspiration, percutaneous cholecystostomy, or cholecystectomy was used. Bile culture was not helpful in the prediction of acute cholecystitis, since results were not available for a minimum of 24-48 hours after aspiration. In addition, gram-stained smears and bile cultures suffered from low sensitivity (48% and 38%, respectively); consequently, a negative test does not allow the diagnosis of acute cholecystitis to be excluded. Bile aspiration of the gallbladder thus has a limited role in the diagnosis of this condition. 相似文献
993.
Twenty percutaneous transluminal angioplasty (PTA) procedures and 13 percutaneous venous embolization (PVE) procedures were performed in 23 patients who either had or were at risk for the development of recurrent bleeding, hepatic encephalopathy, or both after surgical shunt placement for portal hypertension. PTA, performed in 12 patients with significant shunt stenoses, resulted in reduction or elimination of gradients in all patients; rebleeding has occurred in only one patient. Complications consisted of one fatal rupture of a mesocaval interposition vein graft and one balloon rupture requiring surgical removal. PVE, performed in 11 patients, resulted in measurable improvement in four of seven encephalopathic patients and temporary control in the two patients with intractable bleeding. Three patients underwent PVE prophylactically. PTA of graft strictures is a valuable treatment modality. Embolization may be helpful in selected cases of hepatic encephalopathy. 相似文献
994.
995.
M. A. van Baak F. T. J. Verstappen B. Oosterhuis 《European journal of clinical pharmacology》1986,30(4):399-406
Summary The effects of oxprenolol, a non-selective beta-blocker with moderate intrinsic sympathomimetic activity (ISA), given by the Oros delivery system, on resting and exercise heart rate and blood pressure have been compared over a 24-h period with those of atenolol, a beta1-selective blocker without ISA. The effects on maximal and submaximal exercise tolerance and perceived exertion were studied in relation to the level of beta-blockade. 9 healthy subjects were treated with placebo, atenolol, 100 mg/day and oxprenolol Oros, 16/260 mg/day in random order, each for 5 days. Progressive maximal exercise tests and submaximal endurance tests at 80% of maximum aerobic exercise capacity were performed 2, 5 and 24 h after intake of the drugs.The reduction of blood pressure 2 and 5 h after drug intake was less pronounced after oxprenolol Oros than after atenolol, but by 24 h after the last dose the effects were similar. The peak level of beta-blockade (i.e. reduction in maximal exercise heart rate) was similar after oxprenolol Oros and atenolol. The minimal level of beta-blockade 24 h after the last dose was greater after oxprenolol Oros than after atenolol. Maximal exercise capacity and submaximal exercise tolerance were impaired after both beta-blockers. The subjective feeling of exertion did not differ between placebo, atenolol and oxprenolol Oros when related to the relative work load, except after the first minute of exercise, when the rating of perceived exertion was higher after atenolol. 相似文献
996.
van Grieken NC Weiss MM Meijer GA Bloemena E Lindeman J Offerhaus GJ Meuwissen SG Baak JP Kuipers EJ 《Journal of clinical pathology》2001,54(1):63-69
BACKGROUND/AIMS: Grading of Helicobacter pylori induced atrophic gastritis using the updated Sydney system is severely limited by high interobserver variability. The aim of this study was to set up a quantitative test of gastric corpus mucosal atrophy in tissue sections and test its reproducibility and correlation with the Sydney scores of atrophy. METHOD: Mucosal atrophy was assessed in 124 haematoxylin and eosin stained corpus biopsy specimens by two experienced gastrointestinal pathologists (EB, JL) according to the updated Sydney system as none (n = 33), mild (n = 33), moderate (n = 33), or pronounced (n = 25). In each specimen, the proportions of glands, stroma, infiltrate, and intestinal metaplasia in the glandular zone were measured as volume percentages using a point counting method. The optimal point sample size, intra-observer and interobserver reproducibility, discriminative power for degrees of atrophy, and correlations with H pylori status were evaluated. RESULTS: Counting 400 points in 200 fields of vision provided the smallest sample size that still had excellent intra-observer and interobserver reproducibility (r > or = 0.96). Overall, the volume percentage of glands (VPGL), infiltrate (VPI), and stroma (VPS) correlated well with the Sydney scores for atrophy (p < or = 0.003). However, no differences were found between non-atrophic mucosa and mild atrophy. No correlation was found between age and either the Sydney grade of atrophy or the VPGL or VPS. In non-atrophic mucosa and mild atrophy, H pylori positive cases showed a significantly higher VPI than did H pylori negative cases. A lower VPGL was seen in H pylori positive cases than in H pylori negative cases in the mild atrophy group. VPS did not correlate with H pylori status within each grade of atrophy. CONCLUSION: Point counting is a powerful and reproducible tool for the quantitative analysis of mucosal corpus atrophy in tissue sections. These data favour the combination of "none" and "mild" atrophy into one category, resulting in a three class grading system for corpus atrophy, when using the updated Sydney system. 相似文献
997.
The framework of pathology: good laboratory practice by quantitative and molecular methods 总被引:5,自引:0,他引:5
Baak JP 《The Journal of pathology》2002,198(3):277-283
Combined confocal laser scan microscopy (CLSM) and Fourier analysis (FA) by non-pathologists of dermal collagen bundle orientation recently gave results superior to subjective evaluation by experts. According to Good Laboratory Practice (GLP) criteria, combined CLSM/FA has not yet been adequately tested to replace current collagen evaluation, but this will not take long. Non-pathologists (clinicians) will then have taken over a laboratory test historically belonging to pathology. A general trend in this direction may develop, because pathologists seem not always to care enough about clinical significance, reproducibility and prognostic value, and new demands for innovative methods. Quantitative image analysis (QIA) and molecular methods are reproducible, inexpensive, and easy to perform; they often have greater value than classical evaluations and their cost-benefit ratio is good. However, their acceptance is not as widespread as one would expect and theoretical reasons which have been advanced do not provide a satisfactory explanation. A formal implementation study was therefore performed, in which an attempt was made to modernize a classical pathology laboratory. An external customer satisfaction investigation showed that 96% of the clinicians were 'very satisfied' (the highest rating possible) with the completed innovations, contrasting with low satisfaction at the beginning. Lack of primary innovative leadership among pathologists was judged to be the dominant cause preventing implementation. Pathologists should focus on carefully reacting to new clinical needs, using GLP criteria. Reproducibility and predictive accuracy should be major themes in any pathology practice. 相似文献
998.
van Aggel-Leijssen DP Saris WH Hul GB van Baak MA 《The American journal of clinical nutrition》2001,73(3):523-531
BACKGROUND: Energy restriction is known to induce a decline in fat oxidation during the postdiet period. Reduced fat oxidation may contribute to weight regain. OBJECTIVE: The present study investigated the effect of the addition of low-intensity exercise training to energy restriction on postdiet fat oxidation and on the contribution of the sympathetic nervous system to fat oxidation. DESIGN: Forty obese men were divided randomly into 2 groups: diet (D) and diet plus exercise (DE). Both groups followed an energy restriction program for 10 wk. Subjects in the DE group also participated in a low-intensity exercise training program [40% maximal oxygen uptake (VO2max)] for 12 wk. Before the intervention and after 12 wk, with subjects at stable body weights, we measured body composition, VO2max, and substrate oxidation at rest, during exercise at 50% VO2max, and during recovery. Measurements were made with and without administration of the beta-adrenergic antagonist propranolol. RESULTS: Both interventions led to significant decreases in body weight, fat mass, and fat-free mass (P < 0.001); these decreases did not differ significantly between the D and DE groups. Neither intervention significantly affected VO2max. The effect of the intervention on the respiratory exchange ratio differed significantly between the D and DE groups [two-way analysis of variance (ANOVA), P < 0.05]. The effect on the beta-adrenergic-mediated respiratory exchange ratio tended to be different between the 2 groups (two-way ANOVA, P = 0.09). CONCLUSION: Addition of low-intensity exercise training to energy restriction counteracts the decline in fat oxidation during the postdiet period. 相似文献
999.
1000.
F Gottrand D Turck V Mitchell JP Farriaux 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(5):399-401
We analyzed the results of 607 small bowel biopsies performed over a seven-year period: 284 biopsies were obtained using a fiberendoscope and 323 biopsies using a Watson capsule. Three to six specimens were removed during endoscopy. The biopsy fragments obtained with the fiberendoscope were deeper than those obtained with the Watson capsule (p less than 0.0001) and were more often located in the duodenum (p less than 0.0001). The failure rate of the fiberendoscope biopsies (1%) was lower than for the Watson capsule biopsies (9%) (p less than 0.0001). Multiple biopsies increased the diagnostic value of fiberendoscopy which was 95% versus 85% for Watson capsule. The mean duration of the endoscopic procedure recorded in 30 children was 6.5 min for four to six samples, i.e. 1.5 min per biopsy specimen. Fiberendoscopy appears to be an efficient and safe method for performing small bowel biopsies in infants and children. 相似文献