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91.
92.
Is the male involved in the aetiology of ectopic pregnancy?   总被引:3,自引:0,他引:3  
We have previously observed a low incidence of ectopic pregnancies in couples having gamete intra-Fallopian transfer (GIFT) with donated spermatozoa. Based on findings in both animal and human models, we proposed the hypothesis that sperm defects may be associated with the expression of paternal genes which cause abnormal early embryo development and predispose the embryos to interact inappropriately with the genital tract epithelium, and so increase the risk of an ectopic implantation. To both confirm and extend the initial observation, GIFT and in-vitro fertilization (IVF) pregnancies entered on the Australian and New Zealand national database between 1979 and 1993 were analysed with regard to the incidence of ectopic pregnancy. There was an increased risk of ectopic pregnancy for IVF relative to GIFT and when spermatozoa from the male partner were used rather than donor spermatozoa. However, when couples were categorized with respect to the aetiology of their infertility, we were unable to show a significant association between ectopic pregnancy and whether spermatozoa from the male partner or a donor were used. We have therefore been unable to confirm a direct association between the source of spermatozoa and ectopic pregnancy.   相似文献   
93.
94.
Equivocal mammographic findings: evaluation with spot compression   总被引:3,自引:1,他引:2  
Berkowitz  JE; Gatewood  OM; Gayler  BW 《Radiology》1989,171(2):369-371
Seventy-five spot compression views of equivocally suspicious lesions detected at routine mammographic examination of 72 women were reviewed in this retrospective study. Sixty-five of the 75 lesions appeared less suspicious on spot compression views, two did not change, and eight appeared more suspicious. Biopsy findings confirmed that the eight more suspicious lesions were cancer. The adjunctive use of spot compression helped characterize equivocal findings seen on routine mammographic views and improved the accuracy of mammographic interpretation.  相似文献   
95.
To assess myocardial glucose metabolism and perfusion in 142 myocardial segments with defects seen at thallium-201 single photon emission computed tomography (SPECT), 27 studies with positron emission tomography (PET) utilizing nitrogen-13 ammonia and fluorine-18 deoxyglucose were performed in 26 patients. Myocardial infarction was defined on the basis of concordant reductions in segmental perfusion and glucose utilization; myocardial ischemia, on the basis of preservation of glucose utilization (metabolic viability) in segments with hypoperfusion at rest. Of the 142 segments analyzed, 101 had fixed defects, 31 had partially reversible defects, and ten had completely reversible defects. Preserved glucose utilization was identified in 47 (46.5%) of the segments with fixed defects and 20 (64.5%) of the segments with partially reversible defects. Of the ten segments with completely reversible defects, five (50%) were normal, and five (50%) exhibited ischemia at PET. Visual improvement in a persistent thallium defect at delayed imaging was not associated with residual glucose metabolic activity. Thus, PET can be used to detect glucose metabolic activity in a significant proportion of myocardial segments with fixed or partially redistributing defects seen at thallium SPECT, which suggests that the extent of tissue viability in patients with ischemic heart disease is underestimated at thallium scintigraphy.  相似文献   
96.
Sewchand  W; Aygun  C; Nicholson  G; Salazar  OM 《Radiology》1986,158(1):251-252
Immobilizers are described that have been used during computed tomography (CT) to ensure reproducibility of patient position during all phases of radiation treatment planning and delivery. The immobilizer causes no degradation or artifact on CT images; hence, the value of the images in radiation treatment planning is not compromised.  相似文献   
97.
Vesico-uterine fistula   总被引:1,自引:0,他引:1  
Nine cases of vesico-uterine fistula caused by injury to the bladder at Caesarean section or by rupture of the uterus and bladder following obstructed labour are described. Symptoms depend on the level of the lesion, menstruation into the bladder and menouria occurring when the fistula is above the internal cervical os: whatever the level, most patients with vesico-uterine fistula present with incontinence of urine. A transperitoneal approach appears to give better results than a transvesical repair.  相似文献   
98.
Thromboembolic complications are frequent in patients with peripartum cardiomyopathy (PPCM). Peripheral artery occlusions are however rare. This case report describes a 30-year-old grand multiparous woman with PPCM complicated by acute lower limb ischaemia and gangrene. This followed left intraventricular thrombi despite maintenance of sinus rhythm. We suspect that the thrombosis is caused by the hypercoagulable state of peripartum period, ventricular dilatation and hypokinesis. The impacts of economic and sociocultural factors in the management of this rare complication of PPCM in a resource depleted nation are highlighted. Keywords: peripartum cardiomyopathy, limb ischaemia.  相似文献   
99.
Inflammatory fibrosis is a characteristic feature of myocarditis, dilated cardiomyopathy (DCM), and congestive heart failure. Th1-type immune responses, mediated by interleukin (IL)-12-induced interferon (IFN)-gamma, are believed to exacerbate autoimmune diseases including myocarditis. In this study, we examined the effect of IL-12R beta 1 and IFN-gamma deficiency on the development of chronic CB3-induced myocarditis using knockout mice. We found increased chronic CB3-induced myocarditis (14.1 to 43.1%, P < 0.001); pericarditis (1.5 to 7.6%, P < 0.001); fibrosis (9.7 to 27.4%, P < 0.05); and the profibrotic cytokines transforming growth factor-beta(1), IL-1 beta, and IL-4 in the hearts of IFN-gamma-deficient mice. All mice infected with CB3 developed DCM, but IFN-gamma-deficient mice developed a fibrous, adhesive pericarditis associated with increased numbers of degranulating mast cells (MCs) in the pericardium (26.6 to 45.9%, P < 0.01), increased histamine levels (716 to 1930 ng/g of heart, P < 0.01), and reduced survival (100 to 43%). In contrast, IL-12R beta 1 deficiency did not significantly alter the development of chronic myocarditis. Thus, IFN-gamma protects against the development of severe chronic myocarditis, pericarditis, and DCM after CB3 infection by reducing MC degranulation, fibrosis, and the profibrotic cytokines transforming growth factor-beta(1), IL-1 beta, and IL-4 in the heart.  相似文献   
100.
The gp120 region of the human immunodeficiency virus type 1 (HIV-1) envelope (env) gene exhibits a high level of genetic heterogeneity across the group M subtypes. The heteroduplex mobility assay (HMA) has successfully been used to assign subtype classifications, but C2V5 primers often fail to amplify African strains. We developed an env gp41-based HMA for which the target sequence is amplified with highly conserved gp41 primers, known to efficiently amplify nucleic acids from HIV-1 group M, N, and O viruses. By using gp41 from a new panel of reference strains, the subtype assignments made by our modified HMA were concordant with those obtained by sequencing and phylogenetic analysis of 34 field strains from 10 countries representing subtypes A to G. Testing of field strains from Nigeria further demonstrated the utility of this modified assay. Of 28 samples, all could be amplified with gp41 primers but only 17 (60.7%) could be amplified with the standard C2V5 primers. Therefore, gp41-based HMA can be a useful tool for the rapid monitoring of prevalent subtypes in countries with divergent strains of circulating HIV-1.  相似文献   
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