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排序方式: 共有657条查询结果,搜索用时 15 毫秒
1.
Mao-Sheng Ran Meng-Ze Xiang Jie Li Jian Huang Eric Yu-Hai Chen Cecilia Lai-Wan Chan Yeates Conwell 《Archives of Suicide Research》2007,11(1):119-127
The aim of this study was to compare the demographic and clinical characteristics of individuals with affective disorders who had attempted suicide at some time in their lives and those who had not made a suicide attempt. In a Chinese rural community, individuals with suicide attempt (N = 30) and those without suicide attempt (N = 166) were assessed with Present State Examination (PSE). Attempters had a significantly higher level of family economic status, higher rate of lifetime depressed mood and hopelessness, and delusions than nonattempters. The logistic regression models also indicated that depressed mood and hopelessness were the most important predictors of suicide attempts. No significant difference in treatment condition was found between attempters and non-attempters. Early identification and interventions focusing on reducing depressed mood, hopelessness, and controlling psychotic symptoms may be helpful in reducing the risk of suicide attempts among individuals with affective disorders residing in the community. 相似文献
2.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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Development of the rete ovarii and its contribution to the cells of the ovary were examined in fetal rats. Histochemical and autoradiographic techniques were used for the observations between days 15 and 21 of gestation. The data presented indicate that the rete system contributes somatic cells to the ovary before birth. The basement membrane which surrounds the cuboidal epithelium of the mesonephric tubules immediately adjacent to the ovary becomes discontinuous on day 15 of gestation. The mesonephric epithelial cells in this region form a knot or clump of pleiomorphic cells, with no apparent tubular organization, and this clump later becomes surrounded by a basement membrane. On day 17 of gestation the newly established fetal rete ovarii is comprised of three regions; (1) the extraovarian mesonephric tubules (ER), (2) intraovarian cords of flattened epithelioid cells which surround the oogonia (IR), and (3) a knot or clump of cells connecting the ER and IR regions (CR). The entire rete system is enclosed by a continuous basement membrane as defined by Periodic Acid-Schiff Reagent techniques. Autoradiographic and quantitative analyses demonstrate that the ER tubule cells proliferate and are incorporated into the other regions of the rete system. These processes begin on day 17 and continue until at least day 21 of gestation. The role these mesonephric tubule cells may play in the regulation of meiosis and their early contribution to the presumptive granulosa cell population is discussed. 相似文献
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Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
7.
Diagnosing CP can range from routine in those with severe disease and obvious calcifications on CT imaging to elusive in those patients with early changes in CP. The workup of suspected CP should follow a progressively noninvasive to more invasive STEP-wise approach in a patient with a suspicious clinical presentation and risk factors that raise their pretest probability of disease. After a thorough history and physical examination, basic laboratories should be obtained such as lipase, amylase, metabolic panel, and indirect PFTs (fecal elastase-1, serum trypsin). Computed tomography remains the best initial imaging modality to obtain as it has good sensitivity for severe CP and may obviate the need for other diagnostic tests. When equivocal, an MRCP should be obtained for a more detailed evaluation of the both the pancreatic parenchyma and ducts. If the diagnosis remains in doubt, EUS should be performed with or without pancreas function testing. ERCP remains a last-line diagnostic test and seldom should be used outside of therapeutic purposes. Future advances should target optimizing current diagnostic tools to more accurately diagnose early CP, as it is in this population where the benefits of delaying progression of CP may have the most profound effect. Likely the best way at establishing a diagnosis in these patients is via pancreatic function testing in the setting of indeterminate EUS results. Biomarker studies of pancreas fluid may supplement diagnosis. 相似文献
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Cholecystokinin-stimulated peak lipase concentration in duodenal drainage fluid: a new pancreatic function test 总被引:1,自引:0,他引:1
Conwell DL Zuccaro G Morrow JB Van Lente F Obuchowski N Vargo JJ Dumot JA Trolli P Shay SS 《The American journal of gastroenterology》2002,97(6):1392-1397
OBJECTIVE: Hormonal stimulation with secretin or cholecystokinin (CCK) is the most sensitive means of assessing pancreatic function. Secretin is not available, and current CCK tests are cumbersome, requiring dual tube intubation and marker perfusion techniques. The aim of this study was to test the efficacy of a new CCK-stimulated pancreatic function test measuring peak lipase concentration. METHODS: A Dreiling gastroduodenal tube was inserted to the ligament of Treitz, and fluid was collected on ice for 80 min in four 20-min aliquots. CCK was infused i.v. at a constant rate of 40 ng/kg/h. Gastric aspirations were discarded. Duodenal aspirates were analyzed for volume and enzyme concentration with a clinical laboratory autoanalyzer. RESULTS: Nineteen healthy volunteers and 18 chronic pancreatitis patients were studied. Lipase concentration and secretory volume showed a peak response by 40 min of stimulation, whereas amylase response was variable. The mean peak lipase concentrations (+/-SEM) for normal volunteers and mild, moderate, and advanced chronic pancreatitis patients were 16.9+/-1.9, 7.9+/-1.7, 3.7+/-1.2, and 2.1+/-0.6 x 10 5 IU/L, respectively. Lower peak lipase concentrations were significantly associated with more advanced chronic pancreatitis (p < 0.001). The receiver operating characteristic curve area for all chronic pancreatitis patients was 0.944 (95% CI = 0.825-0.985). A peak lipase concentration of 780,000 IU/L provided a sensitivity and specificity of 0.833 and 0.867, respectively. This CCK test was well tolerated and without complications. CONCLUSIONS: Lipase concentration in duodenal fluid increases nearly 3-fold from baseline after CCK stimulation in healthy volunteers but is markedly reduced in patients with chronic pancreatic disease. Peak lipase concentration is a significant predictor of chronic pancreatitis and correlates with severity of pancreatic disease. Aspiration of duodenal drainage fluid with a Dreiling tube and analysis with a laboratory autoanalyzer are less cumbersome than marker perfusion and back titration techniques. Measurement of enzyme concentration instead of output could lead to the development of an endoscopic or through-the-scope screening method for assessing patients with suspected chronic pancreatitis or chronic abdominal pain. 相似文献