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991.
Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis.  相似文献   
992.
The hepatitis delta virus (HDV) is a small RNA virus that encodes a single protein and which requires the hepatitis B virus (HBV)-encoded hepatitis B surface antigen (HBsAg) for its assembly and transmission. HBV/HDV co-infections exist worldwide and show a higher prevalence among selected groups of HBV-infected populations, specifically intravenous drug users, practitioners of high-risk sexual behaviours, and patients with cirrhosis and hepatocellular carcinoma. The chronic form of HDV-related hepatitis is usually severe and rapidly progressive. Patterns of the viral infection itself, including the status of co-infection or super-infection, virus genotypes (both for HBV and HDV), and persistence of the virus’ replication, influence the outcome of the accompanying and manifested liver disease. Unfortunately, disease severity is burdened by the lack of an effective cure for either virus type. For decades, the main treatment option has been interferon, administered as mono-therapy or in combination with nucleos(t)ide analogues. While its efficacy has been reported for different doses, durations and courses, only a minority of patients achieve a sustained response, which is the foundation of eventual improvement in related liver fibrosis. The need for an efficient therapeutic alternative remains. Research efforts towards this end have led to new treatment options that target specific steps in the HDV life cycle; the most promising among these are myrcludex B, which inhibits virus entry into hepatocytes, lonafarnib, which inhibits farnesylation of the viral-encoded L-HDAg large hepatitis D antigen, and REP-2139, which interferes with HBsAg release and assembly.  相似文献   
993.
994.
BACKGROUND: Antiviral therapy for chronic hepatitis C virus (HCV) infection has led to a reduction in the incidence of hepatocellular carcinoma (HCC). The purpose of the present paper was to assess whether antiviral therapy might suppress tumor recurrence and influence overall survival in patients with HCV-related HCC who had complete ablation of nodules by non-surgical treatments. METHODS: Twenty patients with three or fewer nodules of HCV-related HCC who were treated with percutaneous tumor ablation and/or transcatheter arterial embolization received combined interferon (IFN; 3 or 5 million units of IFN alpha-2b thrice weekly) plus ribavirin (1000-1200 mg per day) therapy for 24-48 weeks after complete ablation of lesions. During the same period, an additional 40 age- and sex-matched control patients with similar characteristics of tumors (sizes, numbers and treatment modalities) and severity of liver disease were recruited from the HCC database. Both recurrence-free survival and actuarial survival were evaluated. RESULTS: Of the 20 patients, 16 completed therapy and 10 showed a sustained response with normalization of alanine aminotransferase and negative HCV-RNA at 6 months after therapy completion. Due to severe side-effects experienced by Child B patients, who mostly discontinued antiviral therapy, clinical outcome was analyzed in the Child A treated (n = 16) and control (n = 33) patients. There was no significant difference in the incidence of local recurrence in sustained responders compared with non-responders or control patients (P = 0.174, 0.1284, respectively); but the second recurrence-free interval in the sustained responders was significantly longer than that of non-responders and the control group (P = 0.0141, 0.0243, respectively). Survival in sustained responders was better than in non-responders and control patients (P = 0.0691, 0.0554, respectively). CONCLUSIONS: These results indicate that successful antiviral therapy after non-surgical tumor ablation for HCV-related HCC may lower tumor recurrence rate and prolong survival.  相似文献   
995.
由于丙型肝炎病毒(HCV)的高度变异性以及缺乏高效率的细胞培养体系,人们对HCV生活史的认识、对相关疫苗和特异性抗病毒药物的研究进展缓慢.寻找高效率的HCV体外细胞培养体系一直是HCV研究的重点,现就近年来在相关领域的研究进展作一综述.  相似文献   
996.
Kaposi’s sarcoma in a patient with severe relapsing polychondritis   总被引:2,自引:0,他引:2  
This report describes the case of a young man who developed Kaposis sarcoma (KS) after corticosteroid treatment for severe tracheal involvement of relapsing polychondritis (RP). The etiopathogenetic mechanisms that may have led to the evolution of this unusual neoplasm are discussed. To our knowledge, this is the first case reported of concomitant RP and KS.  相似文献   
997.
Summary Background: In this study we investigated the frequency, symptoms and predisposing factors of respiratory syncytial virus (RSV) infection during the 1st year of life in infants with obstructive airway disease in comparison with infants without airway disease. Patients: We enrolled 216 infants in their 1st year of life, who were hospitalized because of obstructive airway disease. As an age- and sex-balanced control group, we examined 133 infants hospitalized for other reasons than airway disease. Method: A deep pharyngeal swab was taken from all infants and immediately examined for the presence of RSV antigen by using an enzyme immunoassay (Directigen?). Patient data were surveyed by a questionnaire. Results: The frequency of RSV infections among infants with obstructive airway disease (34.3%; n = 74) differed significantly from the control group (15%; n = 20; p < 0.01). The frequency of RSV-infected infants with obstructive airway disease decreased with age ranging from 39.1% in trimenon I to 29.0% in trimenon IV. This trend was not observed in the control group. With respect to clinical symptoms and risk factors, there were no differences between RSV-infected versus noninfected infants. Conclusion: RSV is an important agent causing lower obstructive airway disease (34.3% of all patients). There are no specific symptoms that can be used for diagnosing RSV infection. In order to prevent other patients on the ward from contracting nosocomial RSV infection and in the light of therapeutic options, one should test newly admitted patients presenting with symptoms of an obstructive airway disease for RSV antigen. On a ward with high-risk patients, we would recommend the use of an RSV test for all new patients. Received: March 21, 1999 · Revision accepted: December 2, 1999  相似文献   
998.
Fifty-six lambda gt11-random-primed-cDNA recombinants of which translation products react with antibodies in the serum drawn from patients with hepatitis C (blood-borne non-A, non-B hepatitis) were cloned from serum pooled from donors presumably infected with hepatitis C. The specificity of these clones for hepaitits C infection was determined using 3 test panels. Of these 29 clones were determined to be specific for Japanese hepatitis C infection. However one of the 29 clones was positive for 1 out of 5 normals in an American test panel while 12 clones were positive for the American panel as well. The remaining 28 clones reacted well with serum from transfusion associated chronic hepatitis C comparing to the sporadic cases in the Japanese panel. When they were tested with normal donors, another clone reacted with a distinct donor group with which the other clones did not react. These results may suggest the presence of heterogeneity in Japanese hepatitis C.  相似文献   
999.
Summary. To clarify the correlation between Epstein-Barr virus (EBV) involvement and hypercytokinaemia in haemophagocytic lymphohistiocytosis (HLH), we analysed serum interferon-gamma levels and EBV-DNA in biological specimens obtained from 25 HLH cases (23 children and two adults). We found that HLH patients showed a wide range of serum IFN-gamma levels from 0.2 to 1300 U/ml, with a median 126U/ml for EBV-DNA-positive (n = 9) and 4.5 U/ml for EBV-DNA-negative (n = 16) groups. The latter group could be classified further into a group with hyper-IFN-gamma-naemia (> 4.5 U/ml) (n = 8) and a group without hyper-IFN-gamma-naemia (n = 8). The survival of the hyper-IFN-gamma-naemic cases was significantly poorer than non-hyper-IFN-gamma-naemic cases. We conclude that EBV is probably involved in one third of the HLH cases, all of whom show hyper-IFN-gamma-naemia, and in the half of the HLH cases with hyper-IFN-gamma-naemia who have a rapidly fatal outcome.  相似文献   
1000.
 目的 探讨影响1-羟基-2-氧-1,8-萘啶-3-甲酰胺类HIV整合酶链转移抑制剂(integrase strand transfer inhibitors, INSTIs)抗整合酶链转移(integrase strand transfer, INST)活性的主要微观结构因素。方法 采用遗传函数逼近法构建了10个1-羟基-2-氧-1,8-萘啶-3-甲酰胺类INSTIs的二维定量构效关系(2d-quantitative structure-activity relationship, 2D-QSAR)模型,从中优选出最优模型,并据此探析影响抑制剂抗INST活性的主要微观结构因素。结果 最优2D-QSAR模型的非交叉验证相关系数R2为0.8555,留一法交叉验证相关系数Q2loo为0.7761,外部交互验证相关系数R2ext为0.94,表明所建模型具有较好的统计学意义和稳定性。结论 1-羟基-2-氧-1,8-萘啶-3-甲酰胺类INSTIs的抗INST活性主要与描述符JX、Dipole_mag、Jurs_PNSA_1和Strain_Energy相关,可为抑制剂的进一步合理设计提供理论依据。  相似文献   
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