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61.
Gene expression of antioxidant enzymes in experimental diabetic neuropathy   总被引:6,自引:0,他引:6  
Chronic hyperglycemia results in a large deficit in nerve blood flow. Both autoxidative- and ischemia-induced lipid peroxidation occurs, with resultant peripheral sensory neuropathy in streptozotocin-induced diabetes in the rat. Free radical defenses, especially involving antioxidant enzymes, have been suggested to be reduced, but scant information is available on chronic hyperglycemia. We evaluated the gene expression of glutathione peroxidase, catalase, and superoxide dismutase (cuprozinc and manganese separately) in L4,5 dorsal root ganglion (DRG) and superior cervical ganglion, as well as enzyme activity of glutathione peroxidase in DRG and sciatic nerve in experimental diabetic neuropathy of 3 months and 12 months durations. We also evaluated nerve electrophysiology of caudal, sciatic-tibial, and digital nerves. A nerve conduction deficit was seen in all nerves in experimental diabetic neuropathy at both 3 and 12 months. Gene expression of glutathione peroxidase, catalase, cuprozinc superoxide dismutase, and manganese superoxide dismutase were not reduced in experimental diabetic neuropathy at either 3 or 12 months. Catalase mRNA was significantly increased in experimental diabetic neuropathy at 12 months. Glutathione peroxidase enzyme activity was normal in sciatic nerve. We conclude that gene expression is not reduced in peripheral nerve tissues in very chronic experimental diabetic neuropathy. Changes in enzyme activity may be related to duration of diabetes or due to post-translational modifications.  相似文献   
62.
We investigated the effect of hypothermia on the vasodilatory response of pial arterioles to hemorrhagic hypotension. The cranial window technique was combined with microscopic video recording in an experiment involving 20 cats anesthetized with pentobarbital. The animals were randomly assigned to either a normothermic or a hypothermic group (32 degrees C). Mean arterial pressure (MAP) was reduced in stepwise increments of 10 mm Hg (from 100 to 50 mm Hg) by blood withdrawal. The diameter of small (50-100 microm) and large (100-200 microm) pial arterioles was measured. In the normothermic group (n = 9), small and large arterioles dilated at a MAP of 60 and 50 mm Hg, and at a MAP of 70, 60, and 50 mm Hg, respectively, compared with baseline values obtained at a MAP of 100 mm Hg. In contrast, in the hypothermic group (n = 11), vasodilation of either small or large arterioles was absent. The percentage diameter of small and large arterioles (percentage of control) was significantly lower at a MAP of 70, 60, and 50 mm Hg in the hypothermic group than the normothermic group. Our in vivo study demonstrates that hypothermia impairs autoregulatory vasodilation of pial arterioles in response to hemorrhagic hypotension. IMPLICATIONS: Deliberate mild hypothermia has been proposed as a means of providing cerebral protection during neurosurgical procedures. Our results suggest that cerebral blood flow autoregulation in response to hemorrhagic hypotension may be impaired during hypothermic conditions, indicating the importance of maintaining perfusion pressure during hypothermic therapy to prevent cerebral ischemia.  相似文献   
63.
We report a very rare case of primary gastric small cell carcinoma (GSCC) that was accompanied with gastric tubular adenocarcinoma. A male in his 60s had an elevated tumor with a central ulceration in the middle stomach. The patient underwent a distal gastrectomy with lymph node dissection. The pathological examination showed two separated lesions of the stomach, which contained the components of primary GSCC and primary gastric tubular adenocarcinoma. Immunohistochemical (IHC) examination demonstrated that the tumor cells in the small cell carcinoma stained positive for synaptophysin, chromogranin A, and neural cell adhesion molecule (NCAM). GSCC cells and adenocarcinoma cells independently metastasized to each regional lymph node. Further studies on the biological behavior of individual tumors may allow the development of new treatment strategies for GSCC.  相似文献   
64.
Dendritic cell leukemia (DCL) or hematodermic tumor is an uncommon subtype of acute leukemia. In contrast to adult cases, children tend to have a less aggressive course. The diagnosis of DCL should be considered when its characteristic morphologic features are present and leukemic cells co‐express CD4 and CD56. Cases of DCL among pediatric patients have been reported to respond to therapeutic regimens for acute lymphoblastic leukemia, but details regarding the specifics of therapy are lacking. Pediatr Blood Cancer 2013; 60: E38–E41. © 2013 Wiley Periodicals, Inc.  相似文献   
65.
During the past 8 years 1501 colposcopies were performed paying a special attention to cervical glands for diagnosis of cervical intraepithelial neoplasia (CIN) and carcinoma. Normal openings could exclude these diseases at the error rate of only 5.1%, while atypical openings could identify them at the high confidence rate of 96.3%. False positive evaluations were mostly attributable to a marked degree of squamous metaplasia in the glands. The absence of gland openings in the main portion of the lesions amounted to 88.6% in invasive carcinomas but to only 12.4% in CIN. Adenoma malignum was a highly characteristic exception.  相似文献   
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AIM: Japan has a shortage of tertiary medical care facilities for maternal and fetal medicine. Establishment of efficient medical transport systems is needed for pregnant women and fetuses with severe complications. Maternal transport by helicopters is expected to shorten transportation time to advanced facilities, although its feasibility has not yet been evaluated. The aim of the present study was to investigate the status of maternal helicopter transport, and conditions of the pregnant patients and children transferred by helicopter to Kameda Medical Center (KMC). METHODS: Between August 2005 and July 2006, 26 pregnant women were transported by helicopters to KMC. RESULTS: The median net flight time was 24 min (range 15-29 min), and the median of estimation of ground transportation time was 125 min (range 90-180 min). The causes for transfers were preterm labor in eight, preterm premature rupture of the membrane in five, cervical incompetence in five, pre-eclampsia in three and other medical reasons in five. Five of the 26 patients were discharged with restored stability of pregnancy. The remaining 21 patients underwent delivery at KMC. The median gestational age was 26 weeks (range 22-33 weeks) at the time of transfer and 31 weeks (range 22-37 weeks) at delivery. Four of 26 neonates who were born at KMC died after birth due to severe premature or congenital anomaly. Seventeen of the remaining 22 neonates, including 10 twins, received treatment in the neonatal intensive care unit. All of the 22 neonates and all the mothers were discharged in good condition. No patients developed any complications requiring treatment during flights. CONCLUSION: Helicopter transfer is feasible for pregnant patients with severe complications.  相似文献   
70.
An 80-year-old man underwent rectal resection and insertion of a central venous catheter through the left subclavian vein 16 years earlier. Following surgery, he developed edema of his left upper limb that became exacerbated and infected. Computed tomography showed occlusion of the subclavian vein and multiple arteriovenous shunts from the branches of the axillary artery to the venous sac of the axillary vein. Angiography confirmed numerous shunts between the branches of the axillary artery and vein and dilated collateral veins. Embolization of the venous sac was performed using coils, alcohol, and glue. Postprocedural angiography showed complete eradication of the nidus.  相似文献   
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