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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Lyme Neuroborreliosis (LNB) has repeatedly been reported to cause cerebral vasculitis. However, there is no reliable information about the incidence of cerebral vessel affection. The majority of reports deal with ischaemic consequences, and there are a few reports of subarachnoid haemorrhage (SAH). We report a case of otherwise unexplained intracerebral haemorrhage (ICH) where clinical and laboratory tests have shown LNB. Late stage LNB might not only cause ischaemic, but haemorrhagic stroke as well. 相似文献
992.
The distribution of filipin-sterol complexes (FSCs) and intramembranous particles (IMPs) in the plasma membrane of the late spermatid of the boar and of the sperm obtained from the epididymides, ejaculates, and uterus 2 hours after mating was examined by a freeze-fracture replica technique. In the late spermatid, the FSC density was found to be very low. A majority of the FSCs in the acrosomal plasma membrane (APM) appeared as protuberances on the E face in the epididymal, ejaculate, and uterine sperm. The density of the FSCs in the principal segment (PS) of the APM was 291 +/- 44 FSC/microns2 (mean +/- standard deviation, S.D.), 322 +/- 41 FSC/microns2 and 355 +/- 31 FSC/microns2 in the caput, corpus, and cauda epididymidis, respectively. In comparison with the cauda epididymal sperm, the FSC density gradually decreased in the PS of the ejaculated (277 +/- 39 FSC/microns2) and uterine sperm (243 +/- 50 FSC/microns2). The reduction was especially remarkable in the equatorial segment (ES), where the density of FSCs in ejaculated and uterine sperm decreased to about half and less than half of that in the cauda epididymal sperm, respectively. Large (13 nm) and small (8 nm) IMPs were distributed evenly and densely in the P face of the APM in the late spermatid, epididymal, and ejaculated sperm. In the uterine sperm, IMP-free areas were observed in the P face of the plasma membrane, a feature thought to represent one of the capacitation changes of the boar sperm. 相似文献
993.
Y Kitagawa M Ueda N Ando K Ishibiki M Kitajima Y Kabayashi T Arai 《Nihon Geka Gakkai zasshi》1992,93(9):914-917
In recent years, the most common causative organism of hospital infections has been methicillin resistant Staphylococcus aureus (MRSA). The major mechanism of beta-lactam resistance in MRSA is attributed to the production of a specific penicillin binding protein (PBP2'), which is a product of mecA gene, with extremely low binding affinities to beta-lactams. In the present study, we have established a rapid identification method of MRSA by sensitive detection of mecA gene using nested PCR. Nested PCR method amplifying the target DNA in two steps enhanced the efficiency of the second round amplification. By means of this method, mecA gene was successfully detected in clinical samples, such as blood, pus, sputum and feces within 3-4 hrs. Rapid diagnosis of MRSA-bacteremia is particularly important for prevention of sever systemic infection. There are some strains of S. aureus which possess mecA gene in spite of low minimal inhibitory concentration of DMPPC. In these strains expression of mecA gene is induced by contact of beta-lactams and they obtain methicillin resistance. Using nested PCR method, these latent MRSA are rapidly and certainly detectable. This method should be useful for early and effective detection of MRSA hospital infections. 相似文献
994.
995.
M Nakaya K Kawazoe K Ohara Y Kosakai Y Kito Y Kawashima 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(9):1764-1766
The authors reported the first case of acute spinal epidural hematoma (SEH) developed after open heart surgery. The patient was noticed that her legs felt weak and numb on the first postoperative day evening. On the next day morning, neurological examination revealed that flaccid paralysis of both legs and also loss of all sensory perception below the level of Th-6 spine bilaterally. The prolonged effect of anesthesia and painless onset made delayed recognition of the lesion. SEH (Th5-7) was diagnosed with MRI and decompressive surgery was immediately done, sixty hours after the beginning of cardiac operation. But in this case neurological deficits were not changed. We concluded that a routine diagnostic approach was very important procedure to find out this serious complication for all patients underwent open heart surgery in early period of its onset. 相似文献
996.
Somatic mutations seem to accumulate slowly with age duringadult life in both mice and men. There is, however, a substantialmutant frequency at birth, suggesting that the rate of accumulationis much higher before birth. This suggests that DNA replicationplays an important role in the generation of spontaneous mutations.Since most cell division and accompanying DNA replication occursearly in development, more mutations would arise during growthand development. Indeed, if the mutations are genetically neutral,the mutant frequency would rise very rapidly during early fetalgrowth, more slowly during later fetal growth and developmentand still more slowly after birth. To test this hypothesis,we have assayed the mutant frequencies from before birth to28 days after birth, by which time most growth has occurred.We have used the F1 mice generated by crossing SWR females andMutaTMMouse males. The MutaTMMouse has a rescuable lacZ/ 相似文献
997.
998.
A subgroup of patients with chronic pancreatitis overexpress the c-erb B-2 protooncogene. 总被引:1,自引:0,他引:1
H Friess Y Yamanaka M Büchler K Hammer M S Kobrin H G Beger M Korc 《Annals of surgery》1994,220(2):183-192
OBJECTIVE: Chronic pancreatitis (CP) is a chronic condition associated with pancreatic fibrosis. A small subgroup of patients with CP develop enlargement of the head of the pancreas (EHP). This study examined some of the mechanisms that may lead to the development of EHP. SUMMARY BACKGROUND: The c-erb B-2 protooncogene encodes a 185-kDa transmembrane growth factor receptor (p185) that regulates cell growth and differentiation. METHODS: The authors analyzed c-erb B-2 expression in samples obtained from the head of the pancreas from 26 patients with CP (5 women, 21 men) using immunohistochemical and molecular technique. A diagnosis of CP with EHP was made when the vertical pancreatic head diameter was greater than 4 cm (14 patients), as determined by contrast-enhanced computed axial tomography scan. Pancreatic tissues from 15 healthy organ donors served as control subjects. RESULTS: In all patients without EHP and in the healthy control subjects, p185 immunoreactivity was present at low levels. In contrast, strong p185 immunoreactivity was observed in acinar and ductal cells in all patients with EHP. By in situ hybridization, c-erb B-2 messenger ribonucleic acid (mRNA) grains were expressed at high levels in patients with CP with EHP in both ductal and acinar cells. Northern blot analysis demonstrated a 4.5-fold increase (p < 0.001) in c-erb B-2 mRNA levels in patients with EHP compared with patients without EHP and healthy control subjects. Southern blot analysis did not reveal c-erb B-2 gene amplification or rearrangement. CONCLUSIONS: These findings indicate the c-erb B-2 is not overexpressed in most patients with CP. However, its overexpression in patients with CP with EHP suggest that c-erb B-2 may contribute to the pathophysiologic processes that lead to pancreatic head enlargement. 相似文献
999.
1000.
During past 30 years, we experienced 253 patients who underwent surgery for myasthenia gravis. Among these patients, 9 were associated with Graves' disease. No patients had thymoma. Five patients underwent thymectomy after they had become euthyroid by medical treatment, though four patients required subtotal thyroidectomy before thymectomy. One patient developed myasthenic crisis following thyroidectomy and was treated with respirator for 5 days. But thymectomy was performed without myasthenic crisis in these four patients between 25 days and 60 days after thyroidectomy. They have been doing well and no see-saw phenomenon was presented. Thymectomy is safe and effective even in the patients with Graves's disease, and we recommend to perform it after they become euthyroid by medical or surgical treatment. 相似文献