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91.
Contribution of antigen-presenting cell major histocompatibility complex gene products to the specificity of antigen-induced T cell activation 总被引:7,自引:25,他引:7 下载免费PDF全文
E Heber-Katz RH Schwartz LA Matis C Hannum T Fairwell E Appella D Hansburg 《The Journal of experimental medicine》1982,155(4):1086-1099
92.
RH Wilson MB FRCS PP Kerr MB MRCP J McLoughlin MD FRCP M Gormley MD MRCP 《International journal of clinical practice》1993,47(6):315-318
SUMMARY Wegener's granulomatosis is a multisystem disorder which rarely presents with gastrointestinal involvement. We report a case in which colitis was the reason for hospital admission. Diagnosis may be difficult unless clinical, serological and histopathological features are all considered. 相似文献
93.
H. Bürgi M. Benguerel J. Knopp H. Kohler H. Studer 《European journal of clinical investigation》1974,4(1):65-69
Abstract. Several authors have postulated that endogenous iodide produced by the deiodination of iodotyrosines in the thyroid feeds into a different thyroidal iodide compartment than transported iodide which enters the gland from outside. One argument for the existence of two separate iodide compartments is the observation that under certain experimental conditions perchlorate completely discharges transported iodide from the thyroid, while it has no such effect on endogenous iodide. This latter observation however has not been confirmed by all studies and remained controversial. – We therefore reinvestigated the effect of perchlorate on the secretion of endogenous iodide by a new, sensitive method. Five normal volunteers received tracer amounts of iodide-125 I p.o. and 11 days later thyroxine-131 I I.V. Two days later the following serial measurements were started: serum protein-bound labelled iodine (PB125 I, PB131 ), serum total thyroxine and urinary excretion of 125 I, 127 I and 131 I. – In the control period the non-thyroxine iodine secretion calculated from the above measurements was 40 μg/day. Under perchlorate 200 mg three times daily this value rose significantly to 66 μg/day. Non-thyroxine iodine comprises the secreted triiodothyronine plus the secreted endogenous iodide. Assuming that the former value remained constant, our data show that perchlorate indeed discharges part, though not all, of the endogenous iodide. These data do not rule out a second iodide compartment, but they are also compatible with a simple one compartment model. 相似文献
94.
Apoprotein measurements and their clinical application 总被引:1,自引:0,他引:1
The apoproteins structurally are closely associated with specific lipoproteins, for example, apoprotein B with VLDL and LDL and apoprotein A-I with HDL. The levels of these apoproteins provide information about the plasma concentrations and metabolism of the lipoproteins with which they are associated. The levels of apoprotein B and apoprotein A-I and the Lp(a) lipoprotein can serve as important predictors of coronary heart disease risk and can provide information not available from blood lipid and lipoprotein lipid levels. For clinicians and public health interests, the decision to use apoprotein measurements and to estimate cardiovascular risk depends on the clinical setting, the availability of standardized apoprotein methods that can be related to age- and sex-specific population-based reference values, and the cost of the measurements. In addition, these apoproteins can be used in specific cases to answer diagnostic questions and provide information about therapeutic response. 相似文献
95.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot. 相似文献
96.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases. 相似文献
97.
Effect of raloxifene on serum triglycerides in women with a history of hypertriglyceridemia while on oral estrogen therapy 总被引:1,自引:0,他引:1
Carr MC Knopp RH Brunzell JD Wheeler BS Zhu X Lakshmanan M Rosen AS Anderson PW 《Diabetes care》2005,28(7):1555-1561
OBJECTIVE: Raloxifene hydrochloride is a selective estrogen receptor modulator that to date has not been shown to cause hypertriglyceridemia in normal, diabetic, or hypertriglyceridemic women. This study was designed to assess the effect of raloxifene on serum triglycerides in postmenopausal women who have a history of increased hypertriglyceridemia with oral estrogen therapy. RESEARCH DESIGN AND METHODS: This was a single-center, uncontrolled, open-label study investigating the effects of 8 weeks of raloxifene (60 mg/day) therapy on plasma lipids. The study subjects were 12 postmenopausal women, ages 49-73 years, with a documented history of oral estrogen-induced hypertriglyceridemia (serum triglycerides > or =3.39 mmol/l [> or =300 mg/dl]). RESULTS: At week 2 of the study, three (25%) of the subjects withdrew from the trial because they developed marked hypertriglyceridemia (>or =11.3 mmol/l [> or =1,000 mg/dl]) during raloxifene therapy. These three women had higher baseline triglyceride and glucose levels, were not being treated with lipid-lowering agents, and were more likely to have diabetes than the other study subjects. The remaining nine patients (75%) completed the 8-week trial and experienced a nonsignificant increase in mean triglyceride levels from baseline to end point. Raloxifene treatment also resulted in a significant 16% decrease in hepatic lipase activity and a 26% increase in HDL(2) levels (P = 0.013 and 0.03, respectively). CONCLUSIONS: Patients with a previous history of hypertriglyceridemia on oral estrogen therapy should have serum triglyceride levels monitored closely after beginning raloxifene therapy and may even require fibrate therapy before beginning raloxifene. 相似文献
98.
PURPOSE: The aim of the study was to assess whether specific indications are associated with poor visualization during wireless capsule endoscopy (WCE) studies . Four hundred consecutive WCE studies performed at our institute were analyzed retrospectively. RESULTS: Data was available on cases involving 176 males and 224 females. About 23 capsules failed to exit the stomach (excluded from the study). Poor visualization was reported in 66 (17%) WCE studies. The most common indications were gastrointestinal (GI) blood loss (271 cases; 72%), abdominal pain and/or diarrhea (73 cases; 19%), and suspected inflammatory bowel disease (46 cases; 12%). Of the 271 patients suffering GI bleeding, visualization was reported to be poor in 53 (19%) patients; among those showing other indications, visualization was poor in 13 (11%) patients (P = 0.02). After controlling for secondary indications and age, GI bleeding was associated with a higher rate of poor visualization compared to all other indications (odds ratio 2.6; 95% confidence interval 1.4-6.8). CONCLUSIONS: Gastrointestinal bleeding as study indication for WCE is associated with a higher rate of poor visualization. 相似文献
99.
The glycoprotein of lymphocytic choriomeningitis virus (LCMV) contains nine potential N-linked glycosylation sites. We investigated the function of these N-glycosylations by using alanine-scanning mutagenesis. All the available sites were occupied on GP1 and two of three on GP2. N-linked glycan mutations at positions 87 and 97 on GP1 resulted in reduction of expression and absence of cleavage and were necessary for downstream functions, as confirmed by the loss of GP-mediated fusion activity with T87A and S97A mutants. In contrast, T234A and E379N/A381T mutants impaired GP-mediated cell fusion without altered expression or processing. Infectivity via virus-like particles required glycans and a cleaved glycoprotein. Glycosylation at the first site within GP2, not normally utilized by LCMV, exhibited increased VLP infectivity. We also confirmed the role of the N-linked glycan at position 173 in the masking of the neutralizing epitope GP-1D. Taken together, our results indicated a strong relationship between fusion and infectivity. 相似文献
100.