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81.
Orphans as a window on the AIDS epidemic in Sub-Saharan Africa: initial results and implications of a study in Uganda 总被引:5,自引:0,他引:5
S S Hunter 《Social science & medicine (1982)》1990,31(6):681-690
Provisional estimates from a Save the Children Fund enumeration study in four Ugandan districts indicate that the total number of orphans (one or both parents missing) ranges between 620,000 and 1,200,000. Needs assessments with guardians and local administrators show that although extended family networks are absorbing these children according to traditional rules, they may be vulnerable to increased mortality due to economic and health stresses on their caretakers, many of whom are elderly persons. The orphan burden will increase in Uganda and other Sub-Saharan African countries over the next few years. Allocation of additional national and international resources must be considered to avert breakdowns in community and familial support systems and consequent increases in under 5 mortality. The orphan burden is a window on the potential for massive social breakdown and dislocation in Sub-Saharan Africa resulting from high AIDS-related mortality. Methodologies for data collection and planning that use indigenous political systems must be built quickly to avert disaster. 相似文献
82.
83.
Twenty three patients with fragile X syndrome underwent cardiovascular assessment. Echocardiography showed dilatation of the aortic root in 12 (52%) and mitral valve prolapse in five (22%), four of whom had an apical mid-systolic click on auscultation. Patients with fragile X syndrome have cardiac defects similar to those seen in other disorders of connective tissue such as Marfan's syndrome and Ehlers-Danlos syndrome. These, and other somatic features, suggest an underlying connective tissue dysplasia. 相似文献
84.
85.
Heather Kent 《Canadian Medical Association journal》1996,154(6):901-902
A Singapore-based company with a subsidiary office in Seattle offers emergency medical assistance to employees of North American companies operating in Asia and South America. The company offers routine medical service and emergency evacuation around the clock. 相似文献
86.
87.
Stephen Hunter Terry Gramlich Karen Abbott Vijay Varma 《Genes, chromosomes & cancer》1993,8(3):172-177
Carcinoma of the esophagus shows a strong male predominance and other epidemiologic differences from cancers arising at other sites. In this study, the prevalence of Y chromosome loss in 29 carcinomas of the esophagus and 53 carcinomas arising elsewhere in the aerodigestive tract was assessed by in situ hybridization of formalin-fixed paraffin-embedded tissue sections. Absence of the Y chromosome was defined as (1) negative staining for Y in neoplastic cells with positive staining for Y in immediately adjacent nonneoplastic epithelial and stromal cells, (2) positive staining of neoplastic cells with control probes for chromosomes X and 17, and (3) similar results at different stringencies and levels of protein digestion. According to these criteria, absence of the Y chromosome was observed in 13 of 14 (93%) adenocarcinomas of the esophagus, 8 of 13 (62%) squamous cell carcinomas of the esophagus, and 5 of 53 (9%) carcinomas arising in other sites. For the neoplasms examined, Y chromosome deletion was strongly and selectively associated with carcinomas, particularly adenocarcinomas, of the esophagus (P < .0001). These findings suggest that Y chromosome loss may be pathogenetically significant in these neoplasms. © 1993 Wiley-Liss, Inc. 相似文献
88.
E M Hunter 《The Australian and New Zealand journal of psychiatry》1988,22(3):264-271
Aboriginal suicide has become an issue receiving national attention because of the association with "deaths in custody". To date little systematic work has been directed to the investigation of suicide among a non-incarcerated Aboriginal population. This paper focuses on deaths by suicide within one geographical area. It identifies two factors, alcoholism and disruption of interpersonal attachments, which may play a causal role in male Aboriginal suicide. The sudden emergence of suicide in this partial descent population, in concert with suicides among incarcerated and non-incarcerated Aborigines elsewhere, suggests that socio-historical forces must be examined to further clarify the phenomenon. 相似文献
89.
Variability in portion sizes of commonly consumed foods among a population of women in the United States 总被引:1,自引:0,他引:1
D J Hunter L Sampson M J Stampfer G A Colditz B Rosner W C Willett 《American journal of epidemiology》1988,127(6):1240-1249
The use of food frequency questionnaires for measuring dietary intake has become widespread in epidemiologic studies. It has been suggested that inquiring about a person's usual serving size of each food, in addition to the frequency of consumption, will improve the accuracy of this method. This approach implies that individuals characteristically eat a specific amount of any particular food, and that this amount can be reported with reasonable accuracy. To investigate the variability of portion sizes, the authors analyzed data for 68 commonly consumed foods, based on four one-week weighed diet histories recorded by 194 Boston-area women aged 34-59 years during 1980 and 1981. For each food, total population variance in portion size was partitioned into within-person (intraindividual) and between-person (interindividual) components. For all but seven food items (yogurt, liver, mixed vegetables, watermelon, pancakes/waffles, cold cereal, and cooked cereal) the within-person variance in portion size exceeded the between-person variance. The mean of the within-person to between-person variance ratios, after exclusion of two outlying foods, was 3.4 for untransformed portion sizes, and 3.2 after portion sizes were loge-transformed. Foods with a high within-person variance also tended to have a high between-person variance. The dominance of within-person variance in portion sizes suggests that the concept of usual portion size is complex, and that subjects may experience substantial difficulty in specifying their "usual" portion size. The smaller contribution of between-person variance to the total variance in portion size suggests that specification of a standard portion size by the investigator may not introduce a large error in the estimation of food and nutrient intake. 相似文献
90.
Summary These studies were designed to determine the role of the central nervous system, the sympathetic nervous system, the adrenal glands and the renal sympathetic nerves in yohimbine-induced renin release in conscious rats. Yohimbine (0.3–10 mg/kg, s.c.) caused time- and dose-related increases in plasma renin activity (PRA) and concentration (PRC) which were accompanied by time- and dose-related elevations of plasma norepinephrine (NE) and epinephrine (Epi) concentrations. Significant positive correlations were found between the increases in PRA and the increases in plasma NE and Epi concentrations caused by yohimbine, and propranolol (1.5 mg/kg, s.c.) blocked 90% of yohimbine (3 mg/kg, s.c.)-induced renin release. Over the entire spectrum of doses of yohimbine, the increases in PRA and plasma NE and Epi concentrations were positively correlated with the decreases in mean arterial pressure (MAP), but the -intercept was positive in every case and the 1 mg/ kg dose of yohimbine consistently increased PRA independent of any change in MAP. Complete renal denervation, as evidenced by a greater than 90% reduction in renal NE content, did not alter the increase in PRA caused by yohimbine (3 mg/kg, s.c.). An increase in circulating plasma catecholamine concentrations appeared to mediate yohimbine-induced renin release since propranolol prevented the rise in PRA caused by yohimbine in renal denervated rats. Prior adrenalectomy (Adx) also failed to prevent the rise in PRA produced by yohimbine (3 mg/kg, s.c.), but a combination of Adx and renal denervation caused a significant impairment of yohimbine-induced renin release. However, neither Adx alone nor the combination of Adx and renal denervation affected the increase in plasma NE concentration caused by yohimbine. Complete transection of the spinal cord at C8 caused a drastic reduction in plasma catecholamine concentrations but did not change basal PRC. Yohimbine (3 mg/kg, s.c.) did not increase PRC or plasma catecholamine concentrations after spinal transection. Based on these results, we conclude that 1) the stimulation of renin release by yohimbine is a secondary neurohormonal consequence of the generalized increase in sympathetic activity caused by yohimbine, 2) the sympathoadrenal activation produced by yohimbine results from an action in the brain which is amplified by the simultaneous blockade of prejunctional 2-adrenoceptors and 3) vasodepressor effects of the larger doses yohimbine cause a baroreflexly-mediated increase in sympathetic activity which interacts in a positive fashion with the central and peripheral sympathoexcitatory effects of yohimbine.
Send offprint requests to T. K. Keeton 相似文献