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51.
There is some evidence that the sympathetic nervous system plays a role in the development and/or maintenance of painful states, and that sympathetic nervous function is altered in these conditions. Our previous experiments showed that electrical stimulation of the lumbar sympathetic trunk (sympathetic stimulation: SS), which normally induces a decrease in blood flow (BF) of plantar skin, induced its BF increase in about 50% of adjuvant-inflamed rats. To investigate the mechanism of this BF-increase response, we examined whether noradrenaline (NA) plays any role in this changed response to SS, and which receptor subtype is involved. We measured paw cutaneous BF response with a laser Doppler flowmeter in rats chronically inflamed with complete Freund's adjuvant. SS induced the BF-increase response in 50-67% of measured sites. Close-arterially injected NA induced the BF-increase response at dosages between 10-100 ng/kg only at the sites with the BF-increase response to SS. The BF-increase and -decrease responses to NA was significantly reduced after the close-arterial injection of either alpha1- or alpha2-adrenoceptor antagonists (p lt; 0.05, respectively). In contrast, although the BF-decrease responses to SS were significantly reduced by administration of alpha1- and alpha2-adrenoceptor antagonist, BF-increase response was reduced only by alpha1-adrenoceptor antagonist, and that only at a higher dose. In addition, the beta-adrenoceptor antagonist had no effects on both responses. These results suggest that the BF-increase response to SS involves, additionally to NA, a non-adrenergic mechanism.  相似文献   
52.
53.
Vidarabine versus acyclovir therapy in herpes simplex encephalitis   总被引:35,自引:0,他引:35  
We randomly assigned 208 patients who underwent brain biopsy for presumptive herpes simplex encephalitis to receive either vidarabine (15 mg per kilogram of body weight per day) or acyclovir (30 mg per kilogram per day) for 10 days. Sixty-nine patients (33 percent) had biopsy-proved disease; 37 received vidarabine, and 32 acyclovir. The mortality in the vidarabine recipients was 54 percent, as compared with 28 percent in the acyclovir recipients (P = 0.008). Six-month mortality varied according to the Glasgow coma score at the onset of therapy. For scores of greater than 10, 7 to 10, and less than or equal to 6, mortality was 42, 46, and 67 percent in the patients treated with vidarabine, as compared with 0, 25, and 25 percent in those treated with acyclovir. A six-month morbidity assessment using an adapted scoring system revealed that 5 of 37 patients receiving vidarabine (14 percent) as compared with 12 of 32 receiving acyclovir (38 percent) were functioning normally (P = 0.021). Eight vidarabine-treated patients (22 percent) and three acyclovir-treated patients (9 percent) had moderate debility. Patients under 30 years of age and with a Glasgow coma score above 10 had the best outcome with acyclovir treatment. We conclude that acyclovir is currently the treatment of choice for biopsy-proved herpes simplex encephalitis.  相似文献   
54.
The early experience is reported here of the use of Intra-operative frozen-section service by telepathology using the Integrated Service Digital Network (ISDN), a commercially available system that is being connected between the Department of Pathology of Tottori University and Matsue City Hospital, a distance of 30 km. The transfer rate is currently 64kbit/s. The frozen-section service was conducted for a total of 117 tissue specimens (organs) from 100 patients between August 1993 and May 1995. The average time taken for examination of each specimen of frozen section was 13min, ranging between 2 and 42min. The average number of transmitted Images was 6.2. Six cases necessitated more than 11 transmitted Images to make a diagnosis, while 13 cases could be diagnosed from two images only. Correct and permissible diagnoses were obtained in 109 (93.2%) out of 117 specimens when comparing the telepathology diagnosis with that of direct microscopy. Improper or misdiag-nosis was made for eight cases (specimens), which were misinterpreted as papillary carcinoma in Basedow's disease, adenoma and hyperplasia in two pheochromocytomas, solid-tubular carcinoma in phyilodes tumor, mastopathy in invasive carcinoma, metastatic carcinoma in astrocytoma, follicular lymphoma in reactive hyperplasia, and lymphadenitis in follicular lymphoma. in retrospect, diagnosis of these cases should have been deferred. From the results, it was concluded that the Intraoperatlve frozen-section service by telepathology may be a worthwhile substitute for hospitals with limited accessibility to local pathology service, in spite of pitfalls in some cases. Well prepared, high-quality frozen sections, sufficient verbal communication with surgeons, and a rather conservative attitude on the part of a well-trained pathologist seem to be the essential Ingredients for reaching an accurate decision when using telepathology.  相似文献   
55.
Recent progress in molecular and cellular biology has led to the development of numerous effective cardiovascular drugs. However, there are still a number of diseases for which no known effective therapy exists, such as peripheral arterial disease, ischaemic heart disease, restenosis after angioplasty, and vascular bypass graft occlusion. Currently, gene therapy is emerging as a potential strategy for the treatment of cardiovascular disease despite its limitations. The first human trial in gene therapy for cardiovascular disease was started at 1994 to treat peripheral vascular disease using vascular endothelial growth factor (VEGF). Then, many different potent angiogenic growth factors were tested in clinical trials to treat peripheral arterial disease and ischaemic heart disease. Improvement of clinical symptoms in peripheral arterial disease and ischaemic heart disease has been reported. This review focuses on the future potential of gene therapy for the treatment of cardiovascular disease. In the future, gene therapy might become a real pharmacotherapy to treat cardiovascular disease.  相似文献   
56.
57.
A case of infantile XX male syndrome with bilateral scrotal testes and penoscrotal hypospadias is presented. No evidence of XX/XY mosaicism or Y chromatin was obtained in preparations from cultures of the peripheral blood, skin fibroblast, or other tissues. Although true hermaphroditism was suspected, exploration of the bilateral gonadal structures failed to detect the presence of ovarian structures, either grossly or microscopically. Furthermore, exploratory laparotomy revealed no Mullerian structures. The difficulty of early diagnosis of XX males in infancy is emphasized.  相似文献   
58.
59.
IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR.  相似文献   
60.
In mice, the mean serum concentration of the acute-phase reactant alpha1-acid glycoprotein increased 34–48% over 14 days following experimental induction of pneumonitis by intranasal inoculation of influenza A virus. Inoculation of undiluted (hemagglutination titer 640) and 10–1 dilution of virus was followed by development of maximum concentrations of alpha1-acid glycoprotein in serum at seven days, of 334g/ml, compared to a concentration in control mice inoculated with irradiated inactivated virus of 225g/ml (P=0.002). Infection with 10–2 virus yielded a peak serum alpha1-acid glycoprotein of 301g/ml at four days, 34% higher than in control mice at four days (P=0.04). There were no differences in alpha1-acid glycoprotein concentrations among virus-infected mice. Influenza A virus pneumonitis was confirmed histologically, by virus isolation, and by serologic testing, but no inoculum-dependent differences were observed. On day 7, there was a direct relationship demonstrated between the severity of pneumonitis evaluated histologically and the serum alpha1-acid glycoprotein concentration (r=0.50;P<0.02). Influenza A pneumonia in mice is associated with increased concentrations of alpha1-acid glycoprotein in serum; the increase may be directly related to the severity of the pulmonary inflammation.  相似文献   
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