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排序方式: 共有686条查询结果,搜索用时 15 毫秒
91.
92.
Andrew KC Lam Ken KH Cheng Rex K Lam Christina FC Lau SY Yau 《Clinical & experimental optometry》1996,79(4):167-172
Myopic crescent, refractive error and axial length were previously investigated in Hong Kong Chinese subjects. The myopic crescent was found to correlate with axial length and myopic refraction. In this study, three groups of Hong Kong Chinese with different degrees of myopia were assessed for optic disc ovalness, refractive error and axial length. The axial length was significantly correlated with the degree of myopia, indicating that the myopia was axial in nature. The regression line shows that 0.44 mm of axial elongation would give about one dioptre of increase in myopia. The elliptical ratio of the optic disc was defined as the maximal disc diameter divided by the minimal disc diameter. All three groups showed an oval disc with vertical axis greater and an increased ovalness for the high myopic group with an elliptical ratio from 1.11 in low myopia to 1.29 in high myopia. There is a small amount (about four degrees) of temporal rotation of this vertical oval orientation, which is independent of the amount of myopia. This result shows an association between axial elongation of the globe and optic disc ovalness, in addition to the previously described temporal myopic crescent. Therefore, in myopic subjects, a vertically oval disc may be associated with a myopic refraction rather than glaucoma. 相似文献
93.
94.
A total of 1000 deaths from injury in England and Wales have been reviewed to establish the incidence and pattern of penetrating injury and the adequacy of its management. Of the 1000 deaths, 71 (7.1 per cent) were due to penetrating injury. There were 32 knife wounds and 30 firearm injuries. Most of the latter were suicides. Only 17 patients (24 per cent) reached hospital alive. Of these cases, 10 had extracranial injury and all 10 deaths were considered to have been potentially preventable when reviewed by four external assessors. One of seven patients with cranial injury was considered to have been a potentially preventable death. The median age of the 11 cases of potentially preventable death was 37 years (range: 7-61 years). Of these, three did not have any surgery for surgically treatable injuries. Seven patients underwent operation and difficulty was encountered in six of these. It appears from our figures that whilst penetrating injury is an uncommon cause of death, it is poorly managed. The implications of this finding for systems of injury care in the United Kingdom are discussed. 相似文献
95.
96.
Distribution of ascorbate in normal primate retina and after photic injury: a biochemical, morphological correlated study 总被引:3,自引:0,他引:3
The levels of reduced and oxidized ascorbates were determined in the normal baboon neural retina and pigment epithelium-choroid. The ascorbate in the neural retina was mainly in the reduced form, while in the pigment epithelium, it existed primarily in the oxidized form. One eye of each of six baboons was exposed to indirect ophthalmoscope light for 30 minutes. Morphologic study showed necrotic photoreceptors, outer segment disorganization, and abnormal pigment epithelial basal infoldings and swollen microvilli. After the light exposure, the values of the reduced ascorbate decreased in both the neural retina and pigment epithelium-choroid of the posterior pole. The possible role of ascorbate as an antioxidant and ascorbate transport into the retina are discussed. 相似文献
97.
Inhibition of calcineurin phosphatase activity in adult bone marrow transplant patients treated with cyclosporine A 总被引:2,自引:1,他引:1
Pai SY; Fruman DA; Leong T; Neuberg D; Rosano TG; McGarigle C; Antin JH; Bierer BE 《Blood》1994,84(11):3974-3979
In vitro studies have demonstrated that cyclosporine A (CsA) acts by inhibiting the phosphatase activity of calcineurin, an important mediator of T-cell activation. The relationship of CsA administration in vivo, calcineurin activity, and graft-versus-host disease (GVHD) has yet to be studied. The calcineurin activities of mononuclear cells isolated from 62 bone marrow transplant recipients and 12 normal volunteers were determined and analyzed with respect to administration of CsA, presence or absence of CsA in plasma, and presence or absence of GVHD. Of 62 patients, 33 were taking CsA and 29 were not. Early posttransplant (< 100 days), the calcineurin activity of patients on CsA was significantly lower than that of patients not on CsA (P = .0004) and than that of normal volunteers (P < .0001). Similarly, late posttransplant (> 100 days), the calcineurin activity of patients taking CsA was inhibited compared with normal volunteers (P < .05). The calcineurin activity of patients with acute GVHD who were taking CsA was lower than that of patients on CsA without acute GVHD matched for time posttransplant (P = .02). Calcineurin activity in patients on CsA with chronic GVHD was similar to those without chronic GVHD on drug. In conclusion, calcineurin activity is significantly suppressed by in vivo administration of CsA. The lower calcineurin activity of patients on CsA with acute GVHD suggests that CsA-resistant GVHD is not the result of inadequate suppression of calcineurin activity. These data suggest that if inhibition of calcineurin is the only physiologic target of CsA administration, simply increasing doses of CsA or treatment with other inhibitors of calcineurin, such as FK506, would not be expected to ameliorate GVHD. 相似文献
98.
C. O’Donnell A. Rotman S. Collett N. Woodford 《Forensic science, medicine, and pathology》2007,3(3):226-232
In May 2005, a multidetector computed tomography (CT) scanner was installed into the mortuary of the Victorian Institute of
Forensic Medicine (VIFM). Since that time most biological material admitted to the institute has been scanned. This article
provides an overview of the experience gained and difficulties encountered by participants in this project. Discussion is
presented on the incorporation of routine CT imaging into autopsy procedures, application of CT in forensic research, and
how we believe the use of cross-sectional imaging will evolve in forensic investigation of the deceased. 相似文献
99.
4-甲氧羰基-4-N-丙酰苯胺基哌啶1位衍生物的合成及其镇痛作用 总被引:2,自引:0,他引:2
本文报道了一系列N-[-1(2-苯乙基-4-甲氧羰基-4-哌啶基]-N-丙酰苯胺(4-甲氧羰基芬太尼)哌啶环1位取代衍生物的合成及其镇痛活性;讨论了结构与镇痛活性之间的关系。药理试验结果表明,大部分化合物具有典型的吗啡样镇痛活性,是一类作用极强的麻醉性镇痛剂。特别是哌啶环1位β-苯环被取代乙烯基替代的化合物具有相当或接近子母体化合物的镇痛活性。其代表物1321的镇痛活性(ED_(50)=0.005mg/kg ip,小鼠,热板法)略强于4-甲氧羰基芬太尼(ED_(50)=0.0063 mg/kg)。 相似文献
100.
ROSS R. T.; MORROW IAN M.; CHEANG MARY SY 《QJM : monthly journal of the Association of Physicians》1988,67(3):487-495
The relationships between transient cerebral and retinal ischemicsymptoms and brachiocephalic angiographic findings were studiedin 464 patients. The arterial abnormalities were more oftenbilateral than the symptoms suggested. Normal angiographic appearanceswere common, although abnormal arteries in patients withoutrelated symptoms were also common. When stenosis of the carotidsystem was 75 per cent or more, there was a strong correlationwith symptoms. 相似文献