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61.
更昔洛韦治疗特发性血小板减少性紫癜应用指征   总被引:1,自引:0,他引:1  
目的探讨更昔洛韦(GCV)治疗人巨细胞病毒(HCMV)感染相关的特发性血小板减少性紫癜的(ITP)应用指征。方法选择血清HCMV DNA PCR和(或)HCMV IgM检测呈阳性ITP患儿46例,采用逆转聚合酶扩增反应(RT-PCR)检测巨核系祖细胞中HCMV晚期抗原mRNA,并行GCV治疗,判定其疗效及应用指征。结果46例血清HCMV-DNA PCR阳性和(或)血清HCMV-IgM阳性的ITP骨髓巨核祖细胞HCMV晚期抗原基因mRNA阳性19例,GCV治疗有效16例,mRNA阴性27例,GCV治疗有效4例。阳性组疗效高于阴性组,有显著性差异(P<0.01)。结论HCMV感染的ITP患儿,若对常规治疗无效,应检测其巨核祖细胞内HCMV晚期抗原基因mRNA,阳性者是应用更昔洛韦的有效指征。  相似文献   
62.
目的:研究人巨细胞病毒(HCMV)UL145序列在先天感染患儿临床株中的基因多态性,探讨HCMV基因多态性与先天感染引起的不同临床症状之间的关系。方法:对16株临床低传代分离株和15株未传代临床株的HCMV临床标本分别进行UL145全序列PCR扩增,对PCR扩增阳性的31例标本进行序列测定及分析,并且与9株已在GenBank递交的HCMVUL145序列进行比较分析。结果:序列分析结果表明31株HCMV临床株的UL145基因是高度保守的。所有临床株的HCMVUL145开放阅读框架均为393bp,编码蛋白含有130个氨基酸。所有临床株的核苷酸同源率为95.9%~100%,编码蛋白的同源率为97.7%~100%。临床症状不同的患儿其HCMVUL145基因及其编码蛋白具有相似的结构。所有先天感染患儿临床株的UL145编码蛋白具有蛋白激酶C(PKC)磷酸化功能位点和酪蛋白激酶(CK2)磷酸化功能位点。结论:HCMVUL145基因在临床株中是高度保守,未发现其与HCMV先天感染不同临床症状间存在明显的关系。HCMV UL145基因的高度保守性在先天感染中具有重要作用。  相似文献   
63.
目的:探讨中药热毒清对人巨细胞病毒(HCMV)体内外的抑制作用及机制。方法:采用定量逆转录聚合酶链反应(RT-PCR)方法检测中药热毒清干预前后感染细胞HCMV晚期mRNA的表达水平,观察感染细胞的病变进展,并在体外实验的基础上将热毒清应用于HCMV活动性感染孕妇的临床治疗,测定治疗前后血清肿瘤坏死因子α(TNF-α)和白细胞介素2(IL-2)的水平。结果:热毒清对  相似文献   
64.
目的:动态研究(CFU-GM)体外增殖的影响.方法:隔日计HCMV AD169体外持续感染后1~19天内黄芪注射液对CFU-GM细胞簇、集落、大集落及细胞总数变化规律.结果:培养后各组CFU-GM增殖均有不同程度的增加,7天达峰后减少.病毒组CFU-GM增殖均较空白组有明显降低(P<0.05);黄芪组、更昔洛韦组和空白组细胞增殖明显高于病毒组(P<0.01);更昔洛韦组和黄芪组CFU-GM增殖显著高于病毒组(P<0.05).结论:黄芪注射液可以促进体外培养HCMV感染CFU-GM的增殖.黄芪注射液;粒--单系祖细胞;人巨细胞病毒;细胞增殖.  相似文献   
65.
We report a case of fulminant myocarditis after a primary cytomegalovirus infection, in a previously healthy 72-year-old woman. The infection underwent clinical and immunologic resolution consequent to treatment with oral valganciclovir. In an immunocompetent host, the primary cytomegalovirus infection is usually asymptomatic or manifests itself as a heterophile-negative mononucleosis-like syndrome. Cytomegalovirus myocarditis is uncommon in immunocompetent patients. After presenting our case, we review the literature on cytomegalovirus myocarditis in immunocompetent individuals.  相似文献   
66.
Cytomegalovirus (CMV) infection in solid-organ transplantation is associated with increased morbidity and mortality, particularly if a CMV mutant strain with antiviral resistance emerges. Monitoring CMV–specific T cell response could provide relevant information for patient care. We and others have shown the involvement of Vδ2neg γδ T cells in controlling CMV infection. Here, we assessed if Vδ2neg γδ T cell kinetics in peripheral blood predict CMV infection resolution and emergence of a mutant strain in high–risk recipients of kidney transplants, including 168 seronegative recipients receiving organs from seropositive donors (D+R−) and 104 seropositive recipients receiving antithymocyte globulins (R+/ATG). Vδ2neg γδ T cell percentages were serially determined in patients grafted between 2003 and 2011. The growing phase of Vδ2neg γδ T cells was monitored in each infected patient, and the expansion rate during this phase was estimated individually by a linear mixed model. A Vδ2neg γδ T cell expansion rate of ˃0.06% per day predicted the growing phase. The time after infection at which an expansion rate of 0.06% per day occurred was correlated with the resolution of CMV DNAemia (r=0.91; P<0.001). At 49 days of antiviral treatment, Vδ2neg γδ T cell expansion onset was associated with recovery, whereas absence of expansion was associated with recurrent disease and DNAemia. The appearance of antiviral–resistant mutant CMV strains was associated with delayed Vδ2neg γδ T cell expansion (P<0.001). In conclusion, longitudinal surveillance of Vδ2neg γδ T cells in recipients of kidney transplants may predict CMV infection resolution and antiviral drug resistance.  相似文献   
67.
The introduction of novel antimyeloma agents has improved the outcome of multiple myeloma (MM) dramatically. However, it has also led to an increasing incidence of Herpesviridae family virus infections, including a high incidence of post‐transplant cytomegalovirus (CMV) reactivation after treatment with novel agents. We herein retrospectively assessed the CMV reactivation in all 120 newly diagnosed patients with MM consecutively seen and treated at our hospital. CMV antigenemia tests were ordered in 58 patients depending on the clinical context, and the incidence of CMV reactivation and proven/suspected CMV disease requiring antiviral therapy was 20% (24 of 120) and 11% (13 of 120) respectively, including those without stem cell transplantation (SCT). The clinical and laboratory characteristics of these patients were compared with those in 34 CMV antigenemia‐negative (CMV‐negative) patients. Patients with extramedullary disease or a low absolute lymphocyte count (ALC) had a higher risk of developing CMV reactivation. In addition, the median duration from the time of MM diagnosis to CMV reactivation was 5.0 months. These results suggest that, regardless of whether or not undergoing SCT, elderly patients with MM receiving novel agents should be monitored for CMV reactivation to allow for the timely diagnosis and treatment, especially for those with extramedullary disease.  相似文献   
68.
Abstract

A number of immunomodulatory therapeutics increase the risk of disease associated with latent herpesviruses such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV), a member of the lymphocryptovirus (LCV) family that infects humans. The diseases associated with loss of immunity to these viruses can have major impacts on patients as well as on the commercial viability of the immunomodulatory therapeutics. In an effort to develop non-clinical methods for measuring effects on anti-viral immunity, we have developed an interferon (IFN)-γ enzyme-linked immunosorbent spot (ELISPOT) assay to quantify the number of CMV or LCV-reactive T-cells in peripheral blood of cynomolgus macaques. After optimization of various parameters, the IFN-γ ELISPOT assay was characterized for specificity, intra-assay, monkey-to-monkey, and longitudinal variability and sensitivity to immunosuppression. The results show that nearly all animals have detectable responses against both CMV and LCV and responses were derived from T-cells specific to the virus of interest. Analyses of variability show assay reproducibility (≤23% CV), and that variability over time in anti-viral responses in individual animals (larger for LCV than for CMV) was ~2-fold in most animals over a 3-month time period, which is predicted to allow for detection of drug-induced changes when using group sizes typical of non-clinical studies. In addition, the IFN-γ ELISPOT assay was capable of detecting decreases in the numbers of CMV and LCV reactive T-cells induced by immunosuppressive drugs in vitro. This assay may allow for non-clinical assessment of the effects of immunomodulatory therapeutics on anti-viral T-cell immunity in monkeys, and may help determine if therapeutics increase the risk of reactivating latent viral infections.  相似文献   
69.
Lymphocytopenia and CD4+ T lymphocytopenia can be associated with many bacterial, fungal, parasite and viral infections. They can also be found in autoimmune and neoplastic diseases, common variable immunodeficiency syndrome, physical, psychological and traumatic stress, malnutrition and immunosuppressive therapy. Besides, they can also be brought into relation, without a known cause, with idiopathic CD4+ T lymphocytopenia. Among viral infections, the Retrovirus, specially the human immunodeficiency virus, is the most frequently cause. However, many acute viral infections, including cytomegalovirus and Epstein Barr virus can be associated with transient lymphocytopenia and CD4+ T lymphocytopenia. As is well known, transient lymphocytopenia and CD4+ T lymphocytopenia are temporary and overcome when the disease improves. Nonetheless, severe CD4+ T Lymphocytopenia associated with chronic infections by human herpes virus has not been reported. We describe 6 cases of human immunodeficiency virus negative patients, with chronic cytomegalovirus and Epstein Barr virus infections and profound lymphocytopenia with clinical symptoms of cellular immunodeficiency. These patients improved rapidly with ganciclovir or valganciclovir treatment. We claim here that it is important to consider the chronic human herpes virus infection in the differential diagnosis of profoundly CD4+ T lymphocytopenia etiology, when human immunodeficiency virus is absent, in order to start effective treatment and to determine, in future studies, the impact of chronic human herpes virus infection in human beings'' health.  相似文献   
70.
BackgroundHuman cytomegalovirus is the most common cause of vertically transmitted viral infection, affecting around 1% of liveborns. Infection is symptomatic in nearly 10% of infected children who are at higher risk of development of severe neurological disorders, including cerebral palsy.AimsTo study the clinical profile of children with cerebral palsy caused by symptomatic congenital cytomegalovirus infection in a multicenter study involving six countries from the Surveillance of Cerebral Palsy in Europe (SCPE) Network.MethodsData on 35 children (13 males, 22 females; mean age at last assessment 12y 6mo, age range 14y 6mo, min 4y, max 18y 6mo) on pre/peri/neonatal history and last clinical assessment were collected. Classification of cerebral palsy and associated impairments was performed according to SCPE criteria.ResultsThe majority of children had bilateral spastic cerebral palsy, 85.7%, with a confidence interval (CI) [69.7–95.2], and 71.4% [CI 53.7–85.4] were unable to walk (GMFCS levels IV–V) while fine motor function was severely affected in 62.8% [CI 44.9–78.5] (BFMF levels IV and V). Most of the children with severe CP had severe associated impairments. 11.4% of children had severe visual and 42.8% severe hearing impairment, 77.1% [CI 59.9–89.6] suffered from epilepsy, also 77.1% had severe intellectual impairment, and speech was undeveloped in 71.4%. Female:male ratio was 1.69:1 and 80% of children were term born.ConclusionsCerebral palsy following symptomatic congenital cytomegalovirus infection seems to be in most cases a severe condition and associated impairments are overrepresented.  相似文献   
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