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排序方式: 共有2550条查询结果,搜索用时 15 毫秒
951.
952.
R Gerlai SP Williams B Cairns N Van Bruggen P Moran A Shih I Caras H Sauer HS Phillips JW Winslow 《Canadian Metallurgical Quarterly》1998,123(1-2):24-35
This study investigated the drinking response and the expression of Fos- and Egr-1-immunoreactivity (Fos-ir; Egr-1-ir) in the brain induced by endogenous angiotensin generated by intracerebroventricular (i.c.v.) injection of renin. Renin induced Fos-ir in the subfornical organ (SFO), median preoptic (MnPO), supraoptic and paraventricular nuclei (SON and PVN), area postrema (AP), nuclei of the solitary tract (NTS) and lateral parabrachial nuclei (LPBN). Renin-induced Egr-1-ir exhibited a similar pattern of distribution as that observed for Fos-ir. The dose of i.c.v. renin that induced expression of immediate early gene (IEG) product immunoreactivity also produced vigorous drinking. When renin-injected rats were pretreated with captopril, an angiotensin converting enzyme inhibitor, drinking was blocked. With the same captopril pretreatment, both Fos- and Egr-1-ir in the SFO, MnPO, SON, PVN, AP and LPBN were also significantly reduced. 相似文献
953.
LC Chen S Manjeshwar Y Lu D Moore BM Ljung WL Kuo SH Dairkee M Wernick C Collins HS Smith 《Canadian Metallurgical Quarterly》1998,58(16):3677-3683
Amplification is a key mechanism whereby a cancer cell increases the message level of genes that confer a selective advantage when they are overexpressed. In breast cancer, there are many chromosome regions present in multiple copies relative to overall DNA copy number (amplicons), and their target genes are unknown. Using differential display, we have cloned and sequenced the full coding region of a candidate amplicon target gene located on chromosome 13. This candidate is the human homologue of the Caenorhabditis elegans cul-4 gene, cul-4A, a member of the novel cullin gene family, which is involved in cell cycle control of C. elegans. cul-4A was amplified and overexpressed in 3 of 14 breast cancer cell lines analyzed, and it was overexpressed in 8 additional cell lines in which it was not amplified. The latter observation, indicating that its overexpression can occur by mechanisms other than gene amplification, suggests that cul-4A plays a key role in carcinogenesis. Moreover, cul-4A was found to be amplified in 17 of 105 (16%) cases of untreated primary breast cancers, and 14 of 30 cases analyzed (47%) were shown by RNA in situ hybridization to overexpress cul-4A. These results suggest that up-regulation of cul-4A may play an important role in tumor progression. 相似文献
954.
M Bhatia MA Wallig B Hofbauer HS Lee JL Frossard ML Steer AK Saluja 《Canadian Metallurgical Quarterly》1998,246(2):476-483
1-Cyano-2-hydroxy-3-butene (CHB) has been reported to cause cell death in rat pancreatic acini. In this report, we describe the time-dependent effects of CHB on mouse acinar cell apoptosis and the effects of CHB-induced acinar cell apoptosis on the severity of secretagogue-induced acute pancreatitis in mice. CHB administration to mice resulted in a time-dependent increase in pancreatic apoptosis, which was maximal 12 hours after CHB administration. The severity of pancreatitis was significantly reduced by prior CHB administration and maximal protection was observed when the caerulein injections were started 12 hours after CHB administration. These observations indicate that induction of apoptosis can reduce the severity of pancreatitis and they suggest that induction of pancreatic acinar cell apoptosis may be beneficial in the clinical management of acute pancreatitis. 相似文献
955.
We describe a healthy, afebrile 26-year-old man who presented to the emergency department with left hemiparesis and cranial nerve deficits caused by meningococcal meningitis. The results of the computed tomographic scan of the head were negative. Magnetic resonance imaging showed lesions in the basal ganglia and caudate consistent with ischemic infarcts. The neurologic deficits initially progressed but improved to near-resolution after 1 month. This case was unusual in that the patient was afebrile despite a high bacterial load and significant neurologic deficits. His presentation thus mimicked a straightforward stroke. Close attention to the physical examination findings led to a comprehensive evaluation that yielded the correct diagnosis. 相似文献
956.
957.
In this paper, we propose the modified dynamic weighted round robin (MDWRR) cell scheduling algorithm, which guarantees the delay property of real‐time traffic and also efficiently transmits non‐real‐time traffic. The proposed scheduling algorithm is a variation of the dynamic weighted round robin (DWRR) algorithm and guarantees the delay property of real‐time traffic by adding a cell transmission procedure based on delay priority. It also uses a threshold to prevent the cell loss of non‐real‐time traffic that is due to the cell transmission procedure based on delay priority. Though the MDWRR scheduling algorithm may be more complex than the conventional DWRR scheme, considering delay priority minimizes cell delay and decreases the required size of the temporary buffer. The results of our performance study show that the proposed scheduling algorithm has better performance than the conventional DWRR scheme because of the delay guarantee of real‐time traffic. 相似文献
958.
HS Park 《Canadian Metallurgical Quarterly》1996,11(2):157-160
A 14-year-old boy with tuberculous pericarditis and tamponade is described. Confirmation was by culture of pericardial aspirate. Though he did not have a cough, acid-fast bacilli were detected following induced sputum. Chest X-ray did not show evidence of pulmonary tuberculosis, but enlarged mediastinal nodes were detected by computerized tomography. He made an excellent response to anti-tuberculous chemotherapy and corticosteroids. 相似文献
959.
960.