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991.
992.
From November 1981 to early March 1982, an outbreak of scleritis and/or iritis occurred among patients treated with a Nipro brand NAC series cellulose acetate capillary dialyzer. The rate of incidence with dialyzers produced in 1982 was significantly higher than that with dialyzers produced in 1981. An extract obtained from the dialyzers caused iritis in rabbits after its infusion into an auricula vein. Glycerol, acetylated carbohydrate (AC) derivatives, urethane derivatives, and polypropyleneglycol were found in the extract. AC derivatives caused iritis in rabbits, whereas they caused hyperemia of the bulbar conjunctiva in dogs. The AC derivatives contained xylose and glucose units in a ratio of 1.6-2.3:1. The amounts of AC derivatives were significantly larger in the extracts from 1982 than from 1981 devices. Moreover, another brand, but the same type, of dialyzer, the Cordis Dow 4000, contained a slight amount of them. These facts show that AC derivatives derived from hemicellulose played a primary role in the outbreak.  相似文献   
993.
We studied the effect of spider toxin (JSTX)--specific blocker of glutamate receptor--on giant synapse of the squid stellate ganglion. JSTX irreversibly blocked the excitatory postsynaptic potential (EPSP) without affecting the presynaptic action potential or the antidromic action potential. L-glutamate depolarized the postsynaptic membrane and suppressed EPSP which may be due to desensitization. The action of glutamate was completely blocked in the presence of JSTX. The results suggest that glutamate is the transmitter at the giant synapse of squid.  相似文献   
994.
995.
The authors experienced 4 cases of calcified postinfarction aneurysm of the left ventricle. They were all male, aged 55 to 71 (mean 64). Risk factor for coronary artery disease was only smoking in 2 patients, but there was none in the others. They had had acute anteroseptal or extensive anterior infarction at age 41-57 years (mean 49.3), and associated major cardiac events 10-22 years (mean 14.5) after acute myocardial infarction. Ventricular tachycardia, congestive heart failure and systemic thromboembolism were seen in 4, 2 and 1 patients respectively. However, none developed angina pectoris. In the 2 patients in whom signal-averaged electrocardiogram was performed, late potential was detected, so it was suspected that ventricular tachycardia could be due to reentry. Left ventricular end-diastolic pressure was elevated in all patients except one and ranged from 11 to 22 mmHg. Left ventricle was dilated in all cases and the end-diastolic volume index ranged from 143 to 503 ml/m2. The left ventricular ejection fraction ranged from 11 to 24%. However, in 2 of the 4 patients, the cardiac index was within normal limits, and evidence of congestive heart failure was absent. In 2 other patients with associated congestive heart failure, cardiac indices were 2.32, 1.56 l/min/m2 respectively. Coronary arteriogram showed a total occlusion in the left anterior descending (LAD) artery in all cases, and only the LAD artery was affected in 2 patients. In the remaining 2 patients, the right coronary arteries also were significantly stenotic or totally occluded, i.e., they had 2-vessel disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Perforin is one of the important cytolytic factors in cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. In this paper, we report rat mAbs against mouse perforin established by immunization with a recombinant mouse perforin fragment. These mAbs reacted with purified mouse perforin prepared from cytoplasmic granules of an NK-like cell line in ELISA and Western blot analysis. However, none of these mAbs blocked the hemolytic activity of mouse perforin or absorbed it when fixed in the solid phase. These results indicate that all of these mAbs react with denatured but not with native mouse perforin. By using a combination of the mAbs, we established a sandwich ELISA, for quantitating the cellular contents of perforin. These mAbs were also useful for immunohistochemical staining analysis, and perforin was detected in the cytoplasmic granules of CTL and NK cell lines. Perforin was also detected in a minor population of lymphocytes of the spleen, liver, and lymph node. In normal spleen cells of 5- to 8-week-old mice, 12-15% of asialo GM1+ cells and 7-21% of CD8+ T cells were perforin-positive, but CD4+ T cells, B cells, and macrophages were totally negative. These data clearly show that perforin is expressed in cells of a cytotoxic character in normal mice, in the same way as in primed mice.  相似文献   
997.
Thymic myoid cells from myasthenia gravis (MG) patients and controls were successfully grown in explant cultures: we have compared them with skeletal muscle cells cultured from biopsies in morphological, immunohistochemical and electrophysiological studies. Some mononucleate cells in thymus cultures were myoglobin- or desmin-positive, but they were much rarer than the otherwise similar fusing myoblasts in muscle cultures. Frequencies of cultured myoglobin-positive cells showed no difference between MG and control and male or female, but were lower in samples of malignant thymoma, in younger cases and in those with less severe MG. Electrophysiologically the resting membrane potentials of cultured thymic multinucleate cells were significantly less than those of cultured skeletal muscle cells, and action potentials by electrical stimulation were rarely observed. In thymus cultures from only one case with malignant thymoma, desmin-positive myotubes had spontaneous irregular contractions followed by electrical firings. It is concluded that there are myoid cells in MG and control thymuses which have the potential to become skeletal muscle fibers morphologically and electrophysiologically, although their frequency and proliferation in culture are quite low.  相似文献   
998.
Internal urethrotomies under direct vision for urethral strictures were carried out in 80 male patients during the past 5 years. None of the patients died and morbidity was minimal. The immediate postoperative success rate was 96.3%. A retrospective review of results showed an overall cure rate of 43.2%. In the patients in whom the stricture recurred after the first operation, the recurrence was recognized in 50% during the first three months and in 80% during the first year. Repeated operations resulted in a significantly higher cure rate than the initial operation. The results were unrelated to the site, length, width, or the multiplicity of the stricture. However, the recurrence rate was significantly higher for traumatic strictures than inflammatory ones. The recurrence rate was lowest when the catheter was indwelling for 4 days.  相似文献   
999.
Recently, tissue polypeptide antigen (TPA) has become of general interest as one of the new tumor-related antigens. In this study, TPA was measured mainly in patients with various gynecological malignancies by radioimmunoassay, and serum TPA levels above 110u/l were considered pathological. The serum TPA level in normal women was 66 +/- 21 u/l (mean +/- S.D.) and the positive rate was 0 percent. Serum TPA levels in patients with cervical cancer, endometrial cancer, ovarian cancer and uterine sarcoma (181 +/- 262, 117 +/- 49, 217 +/- 215, 142 +/- 49u/l) and positive rates (55, 40, 53, 75 percent) were significantly higher than those in normal women. Serum TPA levels in patients with advanced or recurrent diseases had a tendency to show highly positive. In all of 13 patients with positive TPA, serum TPA levels were significantly reduced and turned negative after the appropriate treatments. However, among our follow-up patients, serum TPA levels were often positive even when there was no clinical evidence of recurrence. Conclusion; serum TPA measurement could be a useful subordinate tumor marker in many patients with gynecological malignancies, even though careful judgement is necessary to interpret positive TPA.  相似文献   
1000.
The relationship between the expression of parathyroid hormone-related protein (PTHrP) by breast cancer and skeletal metastases, was investigated using a monoclonal antibody against human PTHrP (4133). The immunohistochemical localization of PTHrP was studied in sections of formalin-fixed, paraffin-embeded tissues from 28 breast cancers obtained surgically between 1980 and 1985. Of the 28 patients, 12 developed skeletal metastases, 8 developed lung metastases, and the other 8 were alive and disease-free at the time of this study. Sixteen of the 28 (57%) tumors showed positive immunoreactivity to 4133, the PTHrP positive ratio being 83% in the patients who developed skeletal metastases, 38% in those who developed lung metastases, and 38% in those without recurrence, respectively. Thus, a significantly higher proportion of the patients who developed skeletal metastases were positive for PTHrP than the other two groups (P < 0.05). Furthermore, the level of positive staining was strongly related to positivity for estrogen and progesterone receptors (P < 0.01). These results are consistent with the hypothesis that PTHrP might be necessary for metastases to erode bone and grow in skeletal sites, and its expression could be related to certain hormones.  相似文献   
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