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51.
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
52.
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
53.
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
54.
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
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57.
Elevation of serum cystathionine levels in patients with cobalamin and folate deficiency 总被引:14,自引:0,他引:14
Homocysteine can be methylated to form methionine by the cobalamin- (Cbl) and folate-dependent enzyme, methionine synthase; serum levels of total homocysteine are elevated in greater than 95% of patients with either Cbl or folate deficiency. Homocysteine can also condense with serine to form cystathionine in a pyridoxal phosphate-dependent reaction catalyzed by cystathionine beta-synthase. Cystathionine is subsequently cleaved to cysteine and alpha-ketobutyrate by the pyridoxal phosphate-dependent enzyme gamma-cystathionase. To assess levels of cystathionine in Cbl and folate deficiency, we developed a new capillary gas chromatographic-mass spectrometric assay and measured cystathionine in the serum of normal subjects and patients with clinically confirmed deficiencies of these vitamins. The normal range for serum cystathionine was 65 to 301 nmol/L (median = 126 nmol/L) for 50 normal blood donors. In 30 patients with clinically confirmed Cbl deficiency, values for cystathionine ranged from 208 nmol/L to 2,920 nmol/L (median = 816 nmol/L) and 26 (87%) had levels above the normal range. In 20 patients with clinically confirmed folate deficiency, cystathionine concentrations ranged from 138 nmol/L to 4,150 nmol/L (median = 1,560 nmol/L) and 19 (95%) had values above the normal range. Five homozygotes for cystathionine beta-synthase deficiency had high values for serum-total homocysteine and low or low-normal values for serum cystathionine that ranged from 30 nmol/L to 114 nmol/L even though they were on treatment with pyridoxine and had partially responded. One patient with a defect in the synthesis of 5-CH3- tetrahydrofolate and five patients with defects in the synthesis of CH3- Cbl had high values for serum-total homocysteine and high values for cystathionine that ranged from 311 nmol/L to 1,500 nmol/L even though they were on treatment with folic acid and Cbl, respectively, and had partially responded. We conclude that levels of cystathionine are evaluated in the serum of most patients with Cbl and folate deficiency and that they are useful in the differential diagnosis of an elevated serum-total homocysteine level. 相似文献
58.
Cionni RJ Osher RH Marques DM Marques FF Snyder ME Shapiro S 《Journal of cataract and refractive surgery》2003,29(9):1668-1673
PURPOSE: To evaluate the results of implantation of a modified capsular tension ring (MCTR) and a posterior chamber intraocular lens (PC IOL) in patients with congenitally subluxated crystalline lenses. SETTING: Cincinnati Eye Institute, Cincinnati, Ohio, USA. METHODS: Ninety eyes of 57 patients with congenital loss of zonular support (Weill-Marchesani syndrome, idiopathic ectopia lentis, and Marfan's syndrome) had phacoemulsification with PC IOL and MCTR implantation. The preoperative examination included best corrected visual acuity (BCVA) and the presence or absence of phacodonesis, lens decentration, and vitreous prolapse. The postoperative evaluation included BCVA and the presence or absence of pseudophacodonesis, PC IOL centration, and posterior capsule opacification (PCO). RESULTS: At the last postoperative examination, the BCVA was 20/40 or better in 80 eyes (88.9%); 1 eye (1.1%) lost 1 line of acuity. Preoperatively, 18 eyes (20%) had phacodonesis; 1 eye had postoperative pseudophacodonesis. Decentration before surgery was present in 86 eyes (95.6%); 6 eyes (6.7%) developed late symptomatic PC IOL decentration a median of 17.84 months +/- 10.73 (SD) after surgery. Other complications were increased intraocular pressure (2.2%), persistent iritis (3.3%), broken suture (10.0%), retinal detachment (1.1%), and PCO (20.0%). CONCLUSIONS: Use of the MCTR resulted in centration of the capsular bag and PC IOL in 90 eyes with congenitally subluxated crystalline lenses. Fixation of a 9-0 polypropylene suture is recommended to decrease the risk for late suture breakage. 相似文献
59.
Osher RH 《Journal of cataract and refractive surgery》2003,29(12):2258; author reply 2258-2258; author reply 2259
60.
CJ Barry AIIP CRA AAIMBI RL Cooper FRACO FRACS RH Eikelboom BE PhD 《Clinical & experimental ophthalmology》1997,25(2):137-143
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance. 相似文献