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91.
Bat Nipah virus, Thailand   总被引:12,自引:0,他引:12  
Surveillance for Nipah virus (NV) was conducted in Thailand's bat population. Immunoglobulin G antibodies to NV were detected with enzyme immunoassay in 82 of 1,304 bats. NV RNA was found in bat saliva and urine. These data suggest the persistence of NV infection in Thai bats.  相似文献   
92.
93.
A comparison of DNA vaccines for the rabies-related virus,Mokola   总被引:6,自引:0,他引:6  
Nel LH  Niezgoda M  Hanlon CA  Morril PA  Yager PA  Rupprecht CE 《Vaccine》2003,21(19-20):2598-2606
Mokola virus, a rabies-related virus, has been reported to date from the African continent only. Like rabies virus, it is highly pathogenic, causes acute encephalitis, and zoonotic events have been documented. Although believed to be rare, there has been an unexplained increase in the number of isolations of the virus in South Africa in recent years. We have cloned and sequenced the glycoprotein (G) and nucleoprotein (N) genes from a South African Mokola virus, and used these in the construction of different DNA vaccines for immunization against Mokola virus. Four vaccines, utilizing different promoters and DNA backbone compositions, were generated and compared for efficacy in protection against Mokola virus. In one of these, both the Mokola virus G and N genes were co-expressed. Two of the single G-expressing DNA vaccines (based on pSG5 and pCI-neo, respectively) protected laboratory mice against lethal challenge, despite major differences in their promoters. However, neither vaccine was fully protective in a single immunization only. Serological assays confirmed titers of virus-neutralizing antibodies after immunization, which increased upon booster vaccine administration. A third construct (based on pBudCE4) was less effective in inducing a protective immune response, despite employing a strong CMV enhancer/promoter also used in the pCI-neo plasmid. Dual expression of Mokola virus G and N genes in pBudCE4 did not enhance its efficacy, under the conditions described. In addition, no significant utility could be demonstrated for a combined prime-boost approach, as no cross-protective immunity was observed against rabies or Mokola viruses from the use of pSG5-mokG or vaccinia-rabies glycoprotein recombinant virus vaccines, respectively, even though both vaccines provided 60-100% protection against homologous virus challenge.  相似文献   
94.
To better understand the role of bats as reservoirs of Bartonella spp., we estimated Bartonella spp. prevalence and genetic diversity in bats in Guatemala during 2009. We found prevalence of 33% and identified 21 genetic variants of 13 phylogroups. Vampire bat–associated Bartonella spp. may cause undiagnosed illnesses in humans.  相似文献   
95.
目的:观察开道散合扶正和胃合剂治疗上消化道癌性狭窄的临床疗效。方法:对40例患者采用口服开道散、扶正和胃合剂联合胃镜下癌灶内注射5-氟脲嘧啶注射液及鸦胆子乳剂方法治疗上消化道癌性狭窄。结果:治疗后无瘤灶消失病例,34例患者肿瘤缩小达50%以上,完全缓解0例,部分缓解34例,稳定4例,进展2例,有效率为85.0%。治疗后患者吞咽困难有了较明显的改善,显效7例,有效31例,无效2例,总有效率95.0%。治疗后所有患者的卡氏评分均有所升高,与治疗前比较,差异有显著性意义(P〈0.05),提示治疗后患者的生活质量有所改善。结论:开道散合扶正和胃合剂治疗上消化道癌性狭窄疗效满意,能使实体瘤缩小、吞咽困难改善、生活质量提高。  相似文献   
96.
Vaccination in conservation medicine   总被引:1,自引:0,他引:1  
Unprecedented human population growth and anthropogenic environmental changes have resulted in increased numbers of people living in closer contact with more animals (wild, domestic, and peridomestic) than at any other time in history. Intimate linkage of human and animal health is not a new phenomenon. However, the global scope of contemporary zoonoses has no historical precedent. Indeed, most human infectious diseases classed as emerging are zoonotic, and many of these have spilled over from natural wildlife reservoirs into humans either directly or via domestic or peridomestic animals. Conservation medicine has recently emerged as a meaningful discipline to address the intersection of animal, human, and ecosystem health. Interest in the development of novel vaccines for wildlife encounters important challenges that may prevent progress beyond the conceptual phase. Although notable examples of successful wildlife immunisation programmes exist, depending upon key considerations, vaccination may or may not prove to be effective in the field. When implemented, wildlife vaccination requires a combination of novel zoonosis pathogen management strategies and public education to balance conservation, economic, and public health issues.  相似文献   
97.
Neuroactive steroids modulate neurotransmission through modulation of specific neurotransmitter receptors such as γ-aminobutyric acid type A (GABAA) receptors. Preclinical studies suggested that neuroactive steroids may modulate anxiety- and depression-related behaviour and may contribute to the therapeutical effects of antidepressant drugs. Attenuations of 3α-reduced neuroactive steroids have been observed during major depression. This disequilibrium can be corrected by successful treatment with antidepressant drugs. However, non-pharmacological antidepressant treatment strategies did not affect neuroactive steroid composition independently from the clinical response. Further research is needed to clarify whether enhancement of neuroactive steroid levels might represent a new therapeutical approach in the treatment of affective disorders. Nevertheless, the first studies investigating the therapeutical effects of exogenously administered dehydroepiandosterone revealed promising results in the treatment of major depression. In addition, in various anxiety disorders alterations of neuroactive steroid levels have been observed. In panic disorder, in the absence of panic attacks, neuroactive steroid composition is opposite to that seen in depression, which may represent counter-regulatory mechanisms against the occurrence of spontaneous panic attacks. However, during experimentally induced panic attacks, there was a pronounced decline in GABAergic neuroactive steroids, which might contribute to the pathophysiology of panic attacks. In conclusion, neuroactive steroids contribute to the pathophysiology of affective disorders and the mechanisms of action of antidepressants. They are important endogenous modulators of depression and anxiety and may provide a basis for the development of novel therapeutic agents in the treatment of affective disorders.  相似文献   
98.
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
99.
In spite of recent progress in the pharmacotherapy of depression major issues are still unresolved. These include the non-response rate of approximately 30% to conventional antidepressant pharmacotherapy, side effects of available antidepressants and the latency of several weeks until clinical improvement. The only non-pharmacological biological treatment options available so far which exert more rapid antidepressant efficacy are electroconvulsive therapy and, as an augmentation strategy, sleep deprivation. Current pharmacological treatments aim to enhance serotonergic and/or noradrenergic neurotransmission. In spite of emerging knowledge, the crucial mechanisms underlying both non-pharmacological treatments, which are responsible for antidepressant efficacy, are not yet clear so far. In the meantime several new pharmacological principles are under investigation with regard to their putative antidepressant potency. These include 5-HT1A receptor agonists, tachykinin receptor antagonists and various interventions within the hypothalamic-pituitary-adrenal system. While there is evidence for antidepressant properties of these new treatments in animal studies, in case series, in open studies and to some degree also in placebo controlled studies, no definite proof for the antidepressant efficacy of these new pharmacological strategies according to the requirements for evaluation of antidepressant drugs has been furnished so far. In contrast, for the established non-pharmacological treatment strategies including bright light therapy the clinical efficacy has been proven at least in subgroups of depression, but more knowledge of the main mechanisms underlying their antidepressant efficacy is still necessary. In addition new non-pharmacological treatments like repetitive transcranial magnetic stimulation, magnetic seizure therapy and Vagus nerve stimulation are currently under development. Nevertheless, a follow-up of both the new pharmacological strategies and non-pharmacological treatment options is of major importance to provide even better strategies for the clinical management of depression, which also is of great socio-economic impact.  相似文献   
100.
Rabies is a zoonosis that results in millions of human exposures worldwide each year. Human monoclonal antibodies (HuMAbs) that neutralize rabies virus may represent one viable strategy for post-exposure prophylaxis in humans, and have many advantages over current human or equine rabies immune globulin. Transgenic mice carrying human immunoglobulin genes were used to isolate human monoclonal antibodies that neutralized rabies virus. Several HuMAbs were identified that neutralized rabies virus variants from a broad panel of isolates of public health significance. HuMAb 17C7 was the most promising antibody identified because it neutralized all rabies virus isolates tested. HuMAb 17C7 recognizes a conformational epitope on the rabies virus glycoprotein which includes antigenic site III. HuMAb 17C7 protected hamsters from a lethal dose of rabies virus in a well-established in vivo model of post-exposure prophylaxis.  相似文献   
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