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991.
束缚应激对局灶性脑缺血小鼠行为的影响 总被引:2,自引:0,他引:2
目的观察束缚应激对局灶性脑缺血模型小鼠运动行为的影响。方法采用阻断左侧大脑中动脉(MCAO)缺血/再灌注小鼠模型,缺血后1周开始束缚应激(每天2h,共2周),应激结束后即行抑郁行为测试。结果束缚应激使局灶性脑缺血小鼠的自发运动明显减少,蔗糖水偏好比降低,而强迫游泳不动时间显著延长,与正常对照组比较差异显著(P〈O.01)。结论施加束缚应激后,局灶性脑缺血小鼠出现明显的抑郁行为,可考虑将其作为一种脑卒中后抑郁(PsD)动物模型,为进一步研究其生物学机制创造条件。 相似文献
992.
Ataxia-telangiectasia (A-T) is characterized by impaired recognition and repair of DNA damage and increased sensitivity to ionizing radiation (IR), cancer, and neurodegeneration. We previously showed pregnant knockout mice lacking the A-T gene product ataxia-telangiectasia mutated (Atm) are highly susceptible to the embryopathic effects of IR, which damages DNA, possibly via generation of reactive oxygen species (ROS). Here we show that Atm more broadly protects against both spontaneous and phenytoin-enhanced embryopathies. In the absence of drug exposure, cultured embryos from pregnant Atm knockout mice showed more embryopathies than wild-type littermates, with a gene dose-dependent decrease in susceptibility from -/- to +/- to +/+ embryos (p < 0.05). A similar but significantly enhanced gene dose-dependent pattern of embryopathic susceptibility was evident in Atm knockout embryos exposed to the ROS-initiating teratogen phenytoin (p < 0.05). These results provide the first evidence that Atm has a broad developmental importance beyond IR embryopathies, possibly by protecting the embryo from constitutive and xenobiotic-enhanced oxidative stress, with even heterozygotes showing increased risk. This developmental role of Atm further implicates DNA damage in ROS-mediated teratogenesis and DNA damage response and repair as risk factors for individual susceptibility. 相似文献
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995.
采用流室定量研究阶跃切应力对内皮细胞释放前列环素(pGI_2)的影响。对流室中的内皮细胞连续100分钟施加1、10、20dyne/cm ̄2的阶跃剪切应力,用放免法测流室的8个时间段流出液的6-keto-PGFi_(1a)。绘出切应力刺激内皮细胞释放PGI_2的曲线。结果表明:未施加切应力时,内皮细胞释放PGI_2的量在检测限以下,施加切应力后,PGI_2释放速率很快达极大值,且又在数分钟内减小.施加阶跃切应力越大,PGI_2释放速率曲线峰值越高,但衰减也越快,在80~100分钟时间内的前列环素释放速率平均值也越大。由此提示,在活体中血液流变学因素一血流切应力对血管内皮细胞释放前列环素有促进作用。 相似文献
996.
Hiroo Takehara M.D. Akira Okada M.D. Masaharu Nishi M.D. Katsuhiro Masamune M.D. 《Pediatrics international》1992,34(5):569-572
We present a case of Peutz-Jegher's syndrome in an 18 year old female who was followed for gastrointestinal polyps for 13 years from the age of 5 years. The patient was treated four times with surgical or endoscopic polypectomy for gastrointestinal polyps. At the age of 14 years, a combined surgical and endoscopic approach for the management of Peutz-Jegher's syndrome was carried out. A large polyp of the ileum required enterotomy for its removal, and another smaller polyp of the upper jejunum was identified and removed by intra-operative total enteroscopy via the anus. Intra-operative enteroscopy allows one to identify polyps that would previously have been missed. A more complete polypectomy can be performed using this technique, allowing the patient with Peutz-Jegher's syndrome a longer interval between laparotomies and a reduction in symptoms attributed to polyps. 相似文献
997.
A case of unilateral superficial testicular dislocation following blunt scrotal trauma is described, including CT findings. 相似文献
998.
Ten patients with subhepatic fluid collections complicating laparoscopic Cholecystectomy were successfully treated by interventional radiological procedures. The series included five abscesses, three hematomas, one biloma, and one serous collection. Abdominal pain or fever developed from 3 to 21 days after the laparoscopic intervention. All patients were asymptomatic 72 h after percutaneous drainage and there were no complications related to the procedure. Subhepatic fluid accumulations are common findings after laparoscopic cholecystectomies and have been considered an unreliable indicator of infection or other postoperative complications. However, the significance of these collections should not be underestimated in symptomatic patients. In such cases we propose diagnostic aspiration and drainage, when necessary, to safely and promptly establish the precise diagnosis and treatment. More serious complications can be avoided by early percutaneous intervention. 相似文献
999.
It is well established that visual display unit (VDU) operators complain of visual fatigue and visual stress during after-work hours. The present study was divided into two parts. In the first part, standard eye examinations were performed on a group of VDU workers (n = 32) and a control group (n = 15); those subjects who were found to have correct vision (n = 16 and 13, respectively) participated in the second part. The eye examinations revealed that on the average, the VDU workers suffered more than twice as many visual impairments as the controls. In those with correct vision, the near point of accommodation was measured at the beginning of the workday at the start of the week, and at the end of the workday, four days later. In the VDU group, the decrease in accommodation was uniformally distributed between zero and 1.0 diopter, whereas among the non-VDU workers, 77% of the decrease was between zero and 0.25 diopter. The dynamic range of accommodation in the VDU workers on the second examination was smaller than on the first. We conclude that some of the visual stress and visual fatigue that developed at work hindered visual activities after work. 相似文献
1000.
A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described. 相似文献