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排序方式: 共有476条查询结果,搜索用时 468 毫秒
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S. MACDONALD HULL W.J. CUNLIFFE B.R. HUGHES 《Clinical and experimental dermatology》1991,16(3):210-211
Sixteen patients with minimal facial acne but with symptoms of dysmorphophobia related to their acne were treated with isotretinoin, 0.5 mg/kg/day, (n = 5); 1 mg/kg/day (n = 11) for 16 weeks. All 16 had previously received long-term antibiotic therapy with no 'perceived' improvement in their acne. Formal psychiatric assessment was not possible through lack of cooperation. Fourteen of 16 patients derived benefit from isotretinoin therapy in that all 14 were subsequently satisfied with the cosmetic results achieved. However, the incidence of relapse was greater than that for a control group, 14 requiring additional therapy in the form of antibiotics or further isotretinoin (seven patients) within 20 months of completing the original course. Patients with acne and dysmorphophobia represent an important group of patients who benefit from treatment with isotretinoin; if possible this should be in conjunction with psychotherapy. 相似文献
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The health promoting school: progress and future challenges in Welsh secondary schools 总被引:12,自引:2,他引:10
SMITH CHRISTOPHER; ROBERTS CHRIS; NUTBEAM DON; MACDONALD GORDON 《Health promotion international》1992,7(3):171-179
Data were obtained from a random sample of 87 secondary schoolsin Wales (UK) about the organization and provision of healtheducation teaching, the implementation of health related policies,and the involvement of outside agencies and professionals inthe planning and delivery of health education programmes. Theresults suggest that schools have made progress in curriculumdevelopment. However, if the concept of the health promotingschool is to be translated into practice, greater attentionwill need to be given us the development of broadly based policiesfor health covering both pupils and staff and the better integrationof school programmes with community resources. Greater understandingof the health promoting school concept by teaching staff andthe development of examples of good practice in embedding healtheducation into national curriculum subjects, are also advocated. 相似文献
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THOMAS T MACDONALD 《Pediatrics international》1994,36(5):532-536
The human mucosal immune system is structurally mature and has all the necessary cellular components to generate an immune response at birth. However, in the absence of dietary antigens and bacterial flora, there are no secondary follicles in the Peyer's patches and virtually no immunoglobulin A plasma cells in the lamina propria. Reactive follicle centers develop after birth but it takes 2 years for mucosal IgA plasma cell density to reach adult levels. T cells are present in the epithelium and lamina propria at birth, albeit at a lower frequency than later in life and there are major differences in phenotype between T cells in fetal intestine and postnatal intestine. There is no information on the impact of the massive antigenic challenge at birth on the mucosal immune system. Well-documented deficiencies in the ability of the blood T cells of the neonate to produce interleukin-4 and interferon-gamma may also occur in the intestine. It is still an open question whether it is better to try to prevent immunological sensitization of the newborn by avoiding potential allergens (i.e. cow's milk), or whether early exposure (as happens when premature infants are given formula feeds) might tolerize the infant. Hydrolysed cow's milk formulae are probably less antigenic than whole cow's milk and have been widely used in the treatment of cow's milk allergy. Some thought is now being given as to whether the prophylactic use of hydrolysates can reduce cow's milk allergy in ‘at-risk’ infants. 相似文献
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Mast cells and T lymphocytes in chronic urticaria 总被引:1,自引:0,他引:1
R. J. BARLOW E. L. ROSS D. M. MACDONALD A. KOBZA BLACK M. W. GREAVES 《Clinical and experimental allergy》1995,25(4):317-322
Mast cells are considered to be the primary effector cells in urticaria but it is possible that lymphocytes contribute to the formation of weals by secreting histamine releasing factors. The aim of this study was to examine the population of mast cells and to quantify the T cell subsets and their activation status in delayed pressure urticaria (DPU), chronic idiopathic urticaria and normal controls. Three biopsies were obtained from each of four patients with chronic idiopathic urticaria but not DPU. Three biopsies were taken from each of 13 patients with DPU, from a combination of unchallenged skin and at 0, 2, 6, 24, 48 and 120 h after weighted steel rods (diameter 1.5 cm) had been applied to the thighs. Three biopsies were similarly obtained from each of four normal controls before an identical pressure challenge and at 6, 24 and 48 h afterwards. The chloracetate esterase stain was used to demonstrate mast cells and an alkaline phosphatase anti-alkaline phosphatase immunohistochemical technique to assess the phenotypic and activation characteristics of the T cell infiltrate. The mast cell count did not differ significantly between unchallenged skin from DPU patients and normal controls. Following a pressure challenge to the DPU patients, the number of stainable mast cells decreased significantly to a level comparable with that in spontaneous weals of chronic idiopathic urticaria. Investigation of T cell subsets showed a preponderance of CD4+ cells over CD8+ cells. There was no evidence of T cell activation in chronic idiopathic urticaria or DPU when compared with normal controls. These data support the view that mast cell degranulation occurs in chronic idiopathic urticaria and suggest that it may also play a role in the pathogenesis of DPU. There was no evidence that lymphocyte activation occurs in either condition. 相似文献
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Regression analyses were performed on per capita wine consumption in four states of the U.S.A. where the availability of wines was increased. In three of four states, wine consumption was found to be significantly greater in the years of the changes than one would expect, based on the regression trends of the previous eight to thirteen years. Differences in findings were probably a reflection of differences in the nature and extent of the increased availability among the four stales. Consumption of beer and spirits was also analysed for the years in question, and substitution from beer or spirits to wine was not found. Finally, alternative explanations for the patterns of increases were examined and considered unlikely. 相似文献
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ABSTRACT: Shaw, A., Maxted, K. J. and Mcdonald, T. H. (Department of Clinical Physics and Bio-Engineering, Glasgow, and Falkirk and District Royal Infirmary, Falkik, Scotland). Indirect measurement of systolic blood pressure in the newborn. A new reliable method. Acta Paediatr Scand, 63: 601, 1974.—The accurate measurement of systolic blood pressure in the newborn by non-invasive means has, in the past, proved difficult. A new reliable method has been developed which employs a rigid, hinged cuff to occlude the limb, and a thermistor circuit to detect the pulse. The performance of the device is compared with measurements obtained by direct arterial catheterization and its use in the routine clinical situation is evaluated. This device is significantly more convenient and reliable than present methods. It is small, self-contained and relatively inexpensive to produce. 相似文献
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J. N. W. N. BARKER H. A. NAVSARIA I. M. LEIGH D. M. MACDONALD 《The British journal of dermatology》1988,119(5):567-572
Experiments were performed to examine the hypothesis that the surface expression of HLA-DR by keratinocytes in certain disease states is conferred by the activity of gamma-interferon, derived from dermal activated T lymphocytes. In vivo studies revealed a spatial relationship between keratinocyte HLA-DR expression and activated T lymphocytes within the dermal inflammatory infiltrate. In vitro studies confirmed that gamma-interferon can induce keratinocyte synthesis of HLA-DR. These results suggest that, in vivo, gamma-interferon produced by activated T lymphocytes induces keratinocyte HLA-DR synthesis and expression. 相似文献
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