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排序方式: 共有332条查询结果,搜索用时 15 毫秒
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Full-frame transform compression of CT and MR images 总被引:3,自引:0,他引:3
64.
Oral lesions of HIV infection in developing countries 总被引:3,自引:0,他引:3
HIV infection has spread rapidly within developing countries since it was first recognized in the early 1980s. The purpose of this paper is to review the prevalence of oral lesions associated with HIV infection (oral HIV) in the developing world, and to identify additional factors that may complicate the presentation of these lesions. Direct comparison of regional and local prevalence studies within Africa, India and Thailand is speculative because there are few reports available. Furthermore, inherent differences in study design, data collection, standardization and calibration of health workers make any inferences inconclusive. Additional prevalence studies of oral HIV lesions associated with systemic disease or social conditions, such as poverty or malnutrition, are needed. In order to provide a basis for the diagnosis and treatment of HIV-associated oral lesions in the developing world, it is important to recognize any confounding factors that may impact on their presentation and management. Elucidation of these various factors may provide a basis for treatment within the developing and developed world. 相似文献
65.
Aerobic and anaerobic thresholds determined from venous lactate or from ventilation and gas exchange in relation to muscle fiber composition 总被引:4,自引:0,他引:4
The aerobic and anaerobic thresholds determined from venous lactate (AerTLa and AnTLa) or from ventilation and gas exchange (AerTr and AnTr) in relation to muscle fiber composition were compared. Twelve subjects were studied in double exercise tests carried out until voluntary exhaustion. They were divided into two groups according to their muscle fiber type in the vastus lateralis muscle: ST group with a majority of slow-twitch fibers (ST% = 66.0% +/- 7.3%) and FT group with a majority of fast-twitch fibers (ST% = 27.7% +/- 8.4%). A 2-min incremental exercise test protocol on a bicycle was used. There were no significant differences between the ST and FT groups in the VO2max or in the Lamax. Neither the AerT nor the AnT related to the VO2max (%) differed between the ST and FT groups. In the FT group the AnTLa occurred 0.70 min in the first test and 1.06 min in the second test earlier than the AnTr, whereas in the ST group the AnTLa occurred at the same time or 0.44 min later, respectively, than the AnTr (P less than 0.05). Expressed as VO2 the differences between thresholds were not so distinct. The results demonstrated that the mutual relation between the AnTLa and AnTr seemed to be dependent on the fiber type majority in exercising muscles (vastus lateralis) among untrained men. 相似文献
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HK Iversen 《Cephalalgia : an international journal of headache》1995,15(4):281-287
The need for valid human experimental models of headache is obvious. Several compounds have been proposed as headache-inducing agents, but only the nitroglycerin (NTG) model has been validated. In healthy subjects, intravenous infusions of the nitric oxide (NO) donor NTG induce a dose-dependent headache and dilatation of the temporal, radial and middle cerebral artery. NTG-induced headache, although less intense, resembles migraine in pain characteristics, but the accompanying symptoms are rarely present. Cephalic large arteries are dilated during migraine headache as well as during NTG headache. N-acetylcysteine enhances the formation of NO and potentiates NTG-induced headache, whereas mepyramine, a H1 -antagonist capable of blocking histamine-induced headache, has no effect. Thus, the headache is dependent on NO or other steps in the NO cascade. The model is useful for pharmacological interventions and sumatriptan reduced the NTG-induced headache. The NTG model may be a valuable tool in the development of future migraine drugs. 相似文献
69.
HK Larsen AG Danielsen D Krustrup K Weismann 《Journal of the European Academy of Dermatology and Venereology》2005,19(5):634-637
Neutrophil dermatosis of the dorsal hands (NDDH) is a recently described skin manifestation regarded as a subset of acute febrile neutrophilic dermatotis (Sweet syndrome). We describe 5 cases with pustular and ulcerative plaques and/or bullae and vesicles of the dorsal hands. Three of the patients also had skin changes at sides other than the hands. Associated conditions were found in two patients, one patient treated with hemo-dialysis for chronic glomerulonephritis, and one patient had suffered from a streptococcal tonsillitis prior to the eruption. Two of the patients had fever, two had neutrophil leucocytosis in peripheral blood and two had elevated sedimentation rates. Histological findings showed signs of vasculitis in biopsies from two of the patients. NDDH is discussed on the basis of prior case reports concerning the subject, and it is concluded that Neutrophil dermatosis of the dorsal hands should be regarded as a localized variety of Sweet syndrome. 相似文献
70.
Headache induced by a nitric oxide donor (nitroglycerin) responds to sumatriptan. A human model for development of migraine drugs 总被引:5,自引:0,他引:5
Experimental "vascular" headache in humans may be used in characterizing new migraine drugs. The effects of sumatriptan on nitroglycerin-(NTG)-induced headache and arterial responses were therefore studied. Following a double-blind randomized crossover design, 10 healthy volunteers received sumatriptan 6 mg s.c. or placebo succeeded by 20 min NTG (0.12 mg/kg/min) infusion. Headache was rated on a 10 points scale. Temporal and radial artery diameters and velocity in the middle cerebral artery (MCA) were measured with ultrasound. Sumatriptan reduced the NTG-induced headache, median score 1.5 versus 4 after placebo ( p <0.01) and decreased temporal and radial artery diameters 75±3 and 86±3% of baseline respectively ( p <0.05), Blood velocity in the MCA was unaffected. The NTG model may prove to be a valuable tool in the development of future migraine drugs. The results suggest that NTG headache in non-migraineurs may share mechanisms with migraine headache. 相似文献