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31.
OBJECTIVES: This study examined the rates and predictors of mortality among sheltered homeless men and women in New York City. METHODS: Identifying data on a representative sample of shelter residents surveyed in 1987 were matched against national mortality records for 1987 through 1994. Standardized mortality ratios were computed to compare death rates among homeless people with those of the general US and New York City populations. Logistic regression analysis was used to examine predictors of mortality within the homeless sample. RESULTS: Age-adjusted death rates of homeless men and women were 4 times those of the general US population and 2 to 3 times those of the general population of New York City. Among homeless men, prior use of injectable drugs, incarceration, and chronic homelessness increased the likelihood of death. CONCLUSIONS: For homeless shelter users, chronic homelessness itself compounds the high risk of death associated with disease/disability and intravenous drug use. Interventions must address not only the health conditions of the homeless but also the societal conditions that perpetuate homelessness. 相似文献
32.
Chrysopoulo MT Jeschke MG Ramirez RJ Barrow RE Herndon DN 《Archives of surgery (Chicago, Ill. : 1960)》1999,134(3):283-286
BACKGROUND: Recombinant human growth hormone (rhGH) has been shown to favorably modulate the acute-phase response and may improve the clinical outcome. OBJECTIVE: To examine whether rhGH attenuates the elevated tumor necrosis factor alpha (TNF-alpha) levels that correlate with increased multiorgan failure and mortality in burned adults and children. DESIGN: Twenty children with burns of greater than 40% of the total body surface area were randomly divided into 2 groups to receive placebo (n = 10) or rhGH, 0.2 mg/kg per day intramuscularly (n = 10). SETTING: Pediatric burn hospital. MAIN OUTCOME MEASURE: Serum TNF-alpha levels by enzyme-linked immunoassay at baseline (day 0) and at 21 and 42 days after injury. For statistical analysis, we used the Kruskal-Wallis and Friedman tests. RESULTS: No significant differences in age (mean +/- SD, 6.2+/-1.6 vs 5.0+/-1.2 years) or percentage of total body surface area burn (mean +/- SD, 65.1%+/-8.2% vs 57.1%+/-5.2%) could be shown between the groups given rhGH and placebo. Baseline TNF-alpha levels were elevated from reference values in both groups. Twenty-one and 42 days after rhGH administration, serum TNF-alpha levels were significantly decreased from those at baseline (P<.05). No significant decrease in TNF-alpha levels was observed in the placebo group (P = .5). CONCLUSIONS: Recombinant human growth hormone significantly lowers serum TNF-alpha levels after burn injury. This is consistent with the beneficial effect that rhGH has on the acute-phase response. 相似文献
33.
Scrapie is a transmissible spongiform encephalopathy, or "prion disease." We investigated the effects of intracerebral Sc237 scrapie inoculation in hamsters on the physiology and morphology of principal cells from neocortical and hippocampal slices. Scrapie inoculation resulted in increased branching of basal dendrites of hippocampal CA1 pyramidal cells (Sholl analysis), reduced amplitudes of medium and late afterhyperpolarizations (AHPs) in CA1 pyramidal cells and layer V neocortical cells, loss of frequency potentiation of depolarizing afterpotentials (DAPs), and double action potentials in synaptically evoked CA1 pyramidal cell responses. Postsynaptic double action potentials could also be evoked in normal hamster CA1 pyramidal cells by acute pharmacological block of AHPs, suggesting that the depressed AHPs in scrapie-infected hamsters caused the action potential doublets. Both the AHP and the DAP potentiations depend on increased intracellular calcium, which suggests that the underlying deficit, in hamsters infected with Sc237 scrapie, may lie in calcium entry and/or homeostasis. Fast IPSPs, passive membrane properties, and density of dendritic spines remained unchanged. These last two results differ markedly from recent studies on mice infected with ME7 scrapie, indicating diversity of pathophysiology in this group of diseases, perhaps associated with the progressive and substantial neuronal loss found in the ME7, and not the Sc237, model. 相似文献
34.
Vaccination for control of Salmonella in poultry. 总被引:1,自引:0,他引:1
Salmonella spp. are facultative intracellular pathogens causing localised or systemic infections, in addition to a chronic asymptomatic carrier state. They are of worldwide economic and public health significance. In poultry, which represent important sources of cheap protein throughout the world, fowl typhoid and pullorum disease continue to cause economic losses in those parts of the world where the poultry industries are continuing to intensify and where open sided housing is common. A number of serotypes that cause human gastro-enteritis are also increasing. The costs or impracticality of improvements in hygiene and management together with the increasing problems of antibiotic resistance suggest that vaccination in poultry will become more attractive as an adjunct to existing control measures. However, our understandings of the immunology of Salmonella infections in poultry is rudimentary and much poorer than that of equivalent infections in mice and live vaccine development for poultry has therefore been largely empirical. In addition to the killed Salmonella vaccines which have been used over the past few years with variable efficacy, a number of live vaccines have become available and some new vaccines will appear on the market over the next few years. These new vaccines should fulfil the criteria of efficacy, safety and compatibility with existing systems for monitoring infection before they are released on to a mass market. In this review we attempt to summarise the current understanding of Salmonella immunology in poultry together with the progress that has been made in poultry vaccine development. 相似文献
35.
Congenital pulmonary atresia with ventricular septal defect: angiographic and surgical correlates 总被引:1,自引:0,他引:1
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries. 相似文献
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38.
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. 相似文献
39.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献
40.