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151.
BACKGROUND: Vascular endothelial growth factor (VEGF) is thought to be the most powerful angiogenic factor in many malignancies while and several reports have determined serum VEGF to be a prognostic indicator for various malignancies. However, serum VEGF may not be suitable for the measurement of circulating VEGF levels, given that clot formation during the process of collecting sample induces platelet activation and the subsequent release of many cytokines. MATERIALS AND METHODS: Blood samples were obtained prior to surgery from 33 patients with colorectal cancer, and additional samples were obtained 6 months post-operatively from 15 of the 33 patients. Plasma levels of VEGF were assessed using the quantitative sandwich-enzyme immunoassay technique. We investigated the relationships between plasma levels of pre-operative VEGF, prognosis and clinicopathological factors in patients with colorectal cancer. In addition, the relationship between pre-operative and post-operative plasma levels of VEGF obtained at 6 months was assessed. RESULTS: Although not significant, a trend was observed for high plasma levels of VEGF to occur with more advanced colorectal cancer. Plasma levels of VEGF were only significantly increased in patients who had recurrence and a worsening of colorectal cancer. In blood samples obtained from 15 patients both prior to surgery and 6 months post-operatively, post-operative mean plasma VEGF tended to decrease relative to the pre-operative level. CONCLUSION: These results suggest that high plasma levels of VEGF may be observed in more advanced colorectal cancer patients, especially in patients who develop recurrence or a worsening of their condition. Thus, such patients may require additional immunochemotherapy after surgery.  相似文献   
152.
Herpes simplex virus type 1-induced acute retinal necrosis   总被引:1,自引:0,他引:1  
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153.
A deficiency of lysosomal acid beta-galactosidase leads to G(M1)-gangliosidosis in humans, which progressively and profoundly affects the brain and other organs mainly in the early infantile period. We report the pathology of mice with targeted disruption of the beta-galactosidase gene. In the central nervous system, vacuolated neurons appeared in the spinal cord 3 days after birth. The vacuolation extended to neurons in the brainstem, cerebral cortex, hippocampus and thalamus and ballooning neurons became prominent with age. The vacuolation also appeared in Purkinje cells without a marked ballooning change. Reactive astrogliosis in the entire brain was marked at the terminal stage of the disease. Immunohistochemical study using anti-ganglioside G(M1) and G(A1) antibodies revealed extensive accumulation of G(M1) and G(A1) in the cerebral neurons. In the liver, however, accumulation of G(M1) was localized in the cytoplasm of hepatocytes, whereas that of G(A1) was localized in foamy macrophages and Kupffer cells. There were no significant abnormalities in the bone, bone marrow, or cornea at any stage. Although there are some phenotypic and biochemical differences between this knockout mouse and human GM1 gangliosidosis, the mouse will be a useful model for therapeutic trials for the human disease.  相似文献   
154.
We report a 73-year-old woman with Ehlers-Danlos syndrome (EDS) and hypertension who had developed various types of cerebrovascular disease. She had suffered from cerebral hemorrhage of the left putamen at the age of 58, of the left parietal lobe at 64 and cerebral infarction of right internal capsule at 71. EDS type II or III was suggested by two times of skin biopsies. A brain CT at the age of 73 revealed a comparatively large cerebral aneurysm in the territory of the anterior cerebral artery. The patient was treated conservatively, but died due to rupture of the aneurysm. The wall of the aneurysm was made up thin collagen fibers without elastic fibers. There were other multiple small aneurysms in the cerebral arteries, but none in other organs. Deposition of acid mucopolysaccharides was noted in the media of the abdominal aorta. Finally, the present case was thought most likely to be of EDS type IV. It was suggested that one of the causes of the cerebral hemorrhage at the ages of 58 and 64 and the infarction at 71 was related to hypertension, since brain MR angiography at 71 showed no clear aneurysms. In cases of EDS, one should consider the possible formation or rupture of cerebral aneurysm even though the course is favorable.  相似文献   
155.
We have previously shown that NS-7 [4-(4-fluorophenyl)-2-methyl-6-(5-piperidinopentyloxy)pyrimidine hydrochloride] reduces the size of cerebral infarction measured by 2,3,5-triphenyltetrazolium chloride staining at 48 h after permanent middle cerebral artery occlusion (MCAO) in rats. To determine whether NS-7 improves the pathological and behavioral changes at the chronic stage of MCAO, the effect of this compound on the cerebral infarction as well as the neurological and cognitive impairments was investigated 7 days after MCAO. Single or five daily injections of NS-7 (0.125–0.5 mg/kg, i.v.) significantly reduced the infarct volume and improved the neuronal dysfunction including the hind leg paralysis, walking disability and motor incoordination, and the deficit of passive avoidance task, although the neuroprotective efficacy was not different among these dosing regimens. On the other hand, the effects of single versus repeated injections of NS-7 at 0.1 or 0.2 mg/kg on the neurological symptoms were compared at 4 weeks after MCAO. At a lower dose, repeated but not single injection of NS-7 significantly improved the neurological symptoms, although the single injection was effective at a higher dose. From these findings, it is suggested that NS-7 reverses the behavioral and cognitive dysfunction observed at the chronic stage of cerebral ischemia by suppressing the cerebral infarction.  相似文献   
156.
157.
As a three-dimensional carrier for cell culture, a honeycomb structure cell scaffold was created from atelopeptide collagen Types I, II, and III. The diameter of the honeycomb pores ranged from 100 to 1,000 microm. The depth of the pores was from 10 to 3,000 mm. The scaffold was elastic and hard. Creation of various shapes was easy, and these shapes were easily maintained. Human fibroblasts, CHO-K1, BHK-21, and bovine endothelial cells were cultured with the scaffold. The growth curves of these cells were satisfactory. These results suggest that this carrier is a suitable scaffold for cell culture and will be useful as a three-dimensional tissue engineering scaffold.  相似文献   
158.
159.
BACKGROUND: The combining of epidural anesthesia with general anesthesia impairs central and peripheral thermoregulatory control and therefore is often accompanied by unintended intraoperative hypothermia. However, little is known about the cardiovascular response to hypothermia during combined epidural and general anesthesia. The authors assessed the effects of hypothermia during such combined anesthesia. METHODS: The authors randomly assigned 30 mongrel dogs anesthetized with isoflurane (1.0%) to three groups of 10: control, receiving general anesthesia alone; thoracic injection, additionally receiving thoracic epidural anesthesia; and lumbar injection, additionally receiving thoracolumbar epidural anesthesia. Core temperature was lowered from 38.5 degrees C to approximately 34 degrees C (mild hypothermia) using a femoral arteriovenous shunt in an external cool water bath. During hypothermia, the authors measured heart rate, cardiac output, and plasma catecholamine concentrations in each group. Ejection fraction was also measured using echocardiography. RESULTS: Compared with measurements during baseline conditions (general anesthesia alone with no epidural injection and no hypothermia) in the control, thoracic, and lumbar injection groups, the injections followed by hypothermia produced 17, 32, and 41% decreases in heart rate; 22, 32, and 47% reductions in cardiac output; 66, 85, and 92% decreases in the epinephrine concentrations; and 27, 44, and 85% decreases in the norepinephrine concentrations. In contrast, ejection fraction did not change in any group. CONCLUSION: Mild hypothermia during combined epidural anesthesia and general anesthesia markedly reduced cardiac output in dogs, mainly by decreasing heart rate.  相似文献   
160.
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