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51.
Little is known about the role of glial cells in the striatum of chronic methamphetamine (METH) users. In this study, we immunohistochemically examined glial reactions in the striatum of chronic METH users who did not abstain from METH use and died of drug intoxication. Human glucose transporter 5 (hGLUT), a useful marker of microglia, and CR3.43, a major histocompatibility complex class II antigen specific for reactive microglia, were immunostained. Glial fibrillary acidic protein (GFAP) and S100Β were used for astrocyte immunohistochemistry. We analyzed 12 chronic METH users and 13 control subjects, and detected a 200–240% increase in the number of hGLUT5-positive cells in chronic METH users (p < 0.01). However, we did not detect any proliferation of CR3.43-positive cells. The number of GFAP-positive astrocytes increased, but this increase was not significant (p > 0.05). Moreover, S100B-positive cell density between the two groups was not significant (p > 0.05). This study demonstrates the absence of reactive gliosis in the striatum of chronic METH users who did not abstain for prolonged periods from METH use. The results suggest that chronic METH use by itself did not activate glial cells in humans and reactive gliosis may not be involved in the mechanism underlying the loss of control in drug intake, which is a characteristic feature of drug addiction.  相似文献   
52.
A case of malignant thymoma presenting as an anterior neck mass is reported. The tumor extended from the thyroid gland to the superior mediastinum. It did not accumulate Tc-99m pertechnetate, but continued to accumulate Tl-201 at the late phase. A fine-needle aspiration cytology from the tumor showed tight clusters of epithelial cells with crowded ovoid nuclei. The tumor was initially diagnosed as thyroid carcinoma, clinically and cytologically. A thymoma with a dominant epithelial component has to be considered in the differential diagnosis of a suspected papillary carcinoma of the thyroid.  相似文献   
53.
We report a rare case of a patient in whom severe subcutaneous and mediastinal emphysema occurred in association with summer-type hypersensitivity pneumonitis and in whom overdistention or disruption of alveoli with obliteration of the respiratory bronchioles was revealed on open lung biopsy. This case suggests that obstructive bronchiolitis with hypersensitivity pneumonitis is an etiologic factor of mediastinal emphysema.  相似文献   
54.
A 25-year-old man was diagnosed with acute myelogenous leukemia (AML), French-American-British (FAB) subtype M0, based on cytochemical and flow cytometric findings. Cytogenetic analysis revealed the chromosome translocations t(9;11)(p22;q23), and MLL gene rearrangement was identified by Southern blotting. In adult AML, MLL gene rearrangement was initially reported in FAB M4 and M5 cases, and recently in M1 and M2 cases, but was rare in M0 or M3 cases. Because the sensitivity of detecting MLL gene rearrangement by cytogenetic analysis is extremely low compared with Southern blotting analysis, the MLL gene may be involved in substantial numbers of adult AML cases, regardless of FAB subtype.  相似文献   
55.
We investigated 32 patients with bacteremia that occurred in the Department of Urology, School of Medicine, Kanazawa University between April, 1983 and March, 1989. This incidence represented 1.9% of the total number of inpatients. The study group comprised 29 males and 3 females, and their age varied from 25 to 82 years with a mean age of 61.7 years. Twenty-two (75%) of the 32 patients had urologic malignancies. The majority of patients were compromised hosts who had one or more (average, 3.8) factors that promoted bacteremia. Urinary tract infections existed in 26 (86.0%) patients before the bacteremic episode and urine cultures revealed a species identical to that simultaneously isolated from the blood in 19 (73.1%) of the 26 patients. Out of the 26 patients, there were 22 (84.6%) with complicated pyelonephritis and 22 (84.6%) with an indwelling urinary tract catheter. In blood cultures, the most common isolate was Staphylococcus epidermidis and gram-positive cocci were cultured at a rate of 43.9% which was higher than that (39.0%) of gram-negative rods. In contrast, in urine cultures, gram-negative rods were isolated predominantly. S. epidermidis and Corynebacterium spp. isolated less frequently in blood than in urine, indicated contaminants. However, Enterococcus spp. and Candida albicans were recognized as causative organisms of bacteremia via the urinary tract, because the urine culture demonstrated a species identical to that obtained from blood in these bacteremic patients. Antibiotic sensitivity tests demonstrated that isolates from blood tended to show tolerance to beta-lactam antibiotics, but had good sensitivity to aminoglycosides.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
56.
OBJECTIVE: Natural cytotoxicity, mediated by natural killer (NK) cells, has been believed to play an important role in inhibiting experimental tumor metastasis, and diminished NK cell activities leads to a high incidence of tumor occurrence. Despite convincing evidence from experimental studies, the role of NK cells in the immunological surveillance against cancer in human is poorly defined. METHODS: The present study was based on a retrospective analysis of data on 156 patients with gastric cancer, who were surgically treated in the Department of Surgery II, Kyushu University Hospital from 1993 to 1996. All patients were examined for NK cell activity based on a peripheral blood sampling done preoperatively. RESULTS: Significant association between NK cell activity and clinicopathological parameters including tumor size, lymphatic involvement, vascular involvement, and lymph node metastases was evident. When comparing the two groups according to NK cell activity, tumors with low NK cell activity tend to have lymphatic involvement. The 5-yr survival rates were 94.6% and 72.3% for those with NK cell activity > 25% lysis and < or = 25% lysis, respectively, the value being statistically significant (p < 0.05). The independent risk factors for prognosis examined by logistic regression analysis were lymphatic involvement. NK cell activity, depth of tumor invasion, and lymph node dissection. CONCLUSIONS: These current data showed that NK cell activity may be related to tumor volume and dissemination. Measurement of preoperative NK cell activity may be pertinent for the prognosis of patients with gastric cancer and for follow-up clinical management.  相似文献   
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59.
Host factors which influence the outcome of pneumonia in the elderly]   总被引:2,自引:0,他引:2  
We examined 135 elderly patients with pneumonia to clarify the factors predicting on the outcomes of the elderly pneumonic patients. In the fatal cases respiratory symptoms such as cough and sputum, except for dyspnea were less frequent but pulmonary infiltrations on chest roentgenograms were more massive as compared with those in the survived cases. Thus, it was suggested that in the fatal cases the more advanced pneumonia had developed at the time when the diagnosis of pneumonia was made. The fatal cases showed hypoalbuminemia, hypocholesterolemia and hyponatlemia more frequently as compared with survived cases. Among these laboratory values, the decreased serum albumin concentration seemed to be most closely correlated with the fatal outcome of the elderly pneumonic patients. There were significant differences in the outcomes among three groups of the patients, those who were the prolonged bed-ridden, those with severe underlying diseases such as cancer and those treated as out-patients. The out patients showed the most favorable outcome and the prolonged bed-ridden patients the worst outcome. Approximately, 39% of the fatal cases were complicated with multiple organ failure. These results suggest that more important factors which affect the outcomes of pneumonia in the elderly may be not merely aging but the conditions of the host at onset of the disease.  相似文献   
60.
We attempted to prove the occurrence of generalized vasospasms in cases with eclampsia/preeclampsia and HELLP syndrome and to suggest the existence of an angiospastic syndrome of pregnancy. Sixteen cases with severe preeclampsia were evaluated. Among them, three cases were complicated by eclampsia and one case with HELLP syndrome. Cranial magnetic resonance angiography (MRA) was performed in 15 cases, and celiac angiography was performed in one case. Vasospasms were observed in 12 cases (75.0%), including all cases involving eclampsia and HELLP syndrome, and cerebral infarction was observed in one case. Typical vasospasms were found by MRA in the middle and posterior cerebral arteries with peripheral ischemic changes in cases with severe preeclampsia and eclampsia. Vasospasms of the hepatic arteries were observed by celiac angiography in a case with HELLP syndrome. Vasospasms are characteristic for patients with eclampsia/preeclampsia and HELLP syndrome, and the existence of an angiospastic syndrome of pregnancy is proposed.  相似文献   
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