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41.
北京地区婴幼儿人类杯状病毒感染状况及型别分析   总被引:36,自引:1,他引:36  
目的 研究人类杯状病毒与北京地区婴幼儿急性腹泻的病原关系。方法 用RT-PCR检测了婴幼儿非细菌性腹泻患儿粪便标本中的杯状病毒核酸,并用地高辛标记的不同型人类杯状病毒的cDNA(NLV基因型Ⅱ型探针CR840和SLV探针A141)作为探针,用斑点杂交对阳性标本进行分型。结果 从233份标本中检测出阳性标本58份(阳性率24.9%):6个月以下的幼儿阳性19份,占阳性标本总数的32.8%,7-12个月的婴儿阳性15份,占总阳性标本总数的25.9%,1-2岁的幼儿阳性9份,占总阳性标本总数的15.5%,2-3岁的阳性5份,占总阳性标本总数的8.6%,3-4岁的阳性4份,占总阳性标本总数的6.9%,5岁以上的儿童的阳性6份,占总阳性标本总数的10.2%,杂交阳性标本共29份,占50.0%:A141探针杂交阳性的标本14份,占24.1%,CR840探针杂交阳性的标本8份,占13.8%,A141和CR840探针杂交均为阳性的标本7份,占12.1%。结论 我国婴幼儿腹泻与人类杯状病毒感染有关,北京地区儿童中存在多种型别杯状病毒的感染,同时显示不同基因型的杯状病毒基因序列之间的差异可以用杂交分型的方法加以区别。  相似文献   
42.
Abstract

The comparative prognostic importance of latest plasma HIV RNA levels (viral loads) and CD4+ cell counts among patients prescribed highly active antiretroviral therapy (HAART) has not been well characterized. Method: We assessed the prognostic value of latest CD4+ cell counts and latest viral loads for progression to AIDS or death and explored their interaction among 432 HIV-infected persons with advanced HIV who were prescribed a protease inhibitor (PI) as their first HAART regimen. Results: Pre-HAART median CD4+ cell count and viral load were 41 cells/mm3 and 126,331 copies/mL, respectively. After 12 months of HAART, the median CD4+ cell count was 154 cells/mm3; 39% of patients had a viral load of 400 copies/mL or lower. Over a median follow-up of 33 months, 109 (25%) of the 432 patients experienced an AIDS event or died. The hazard ratio for AIDS or death for those with latest CD4+ cell count <50 cells/mm3 versus ≥200 cells/mm3 was 13.9 (95% CI 6.5 to 29.7) without adjustment for latest viral load measurements and 9.5 (95% CI 4.0 to 22.5) after adjustment for latest viral load. In contrast, the hazard ratio for AIDS or death for those with viral load ≥100,000 versus <400 copies/mL was 4.2 (95% CI 2.3 to 7.7) without adjustment for latest CD4+ level and 1.2 (95% CI 0.6 to 2.4) with adjustment for latest CD4+ cell count. Conclusion: We conclude that when latest CD4+ cell count and viral load are considered separately, both are significantly related to AIDS or death; when these markers are jointly considered, the association of viral load with AIDS or death is substantially diminished. Latest CD4+ levels are more strongly related to AIDS or death than latest viral load levels in patients on HAART.  相似文献   
43.
Abstract

Purpose: Antiretroviral therapy has improved the prognosis for many individuals with HIV infection. Consequently, HIV infection has become a chronic and manageable disease with increased risk of cardiovascular disease. Isolated diastolic dysfunction (DD) may be the first indication of underlying cardiac disease and an early marker of coronary artery disease. Our aim was to assess the prevalence of DD in HIV-infected patients. Methods: In this cross-sectional cohort study, 698 unselected patients were included. All subjects underwent two-dimensional transthoracic echocardiography with tissue Doppler imaging. Results: The prevalence of DD among the HIV-infected patients was 48%. Patients with DD were characterized by older age, higher body mass index, higher total cholesterol, arterial hypertension, and diabetes mellitus. Diabetes mellitus and arterial hypertension were associated with approximately four times the risk for DD (odds ratio [OR] 3.9, 95% CI 1.65–9.17; OR 3.8, 95% CI 2.49–5.71, respectively). Persons with hyperlipidemia were approximately one and a half times more likely to have DD than those without hyperlipidemia (OR 1.5, 95% CI 1.12–2.07). Conclusions: In our study, an impressive high prevalence of DD in HIV-infected patients was demonstrated. Traditional cardiovascular risk factors substantially contributed to the development of DD in the HIV-infected cohort.  相似文献   
44.
45.
In recent years a significant increase in the incidence of Serratia marcescens infections was noted at the Chang Gung Memorial Hospital, Taoyuan, Taiwan. A review of laboratory (1991 to 2002) and infection control (1995 to 2002) records showed the possibility of an extended epidemic of nosocomial urinary tract infections (UTIs) caused by S. marcescens. Therefore, in 1998 and 1999, 87 isolates were collected from patients with such infections and examined and another 51 isolates were collected in 2001 and 2002. The patients were mostly elderly or the infections were associated with the use of several invasive devices. S. marcescens was usually the only pathogen found in urine cultures in our study. Neither prior infections nor disseminated infections with the organism were observed in these patients. Resistance to most antibiotics except imipenem was noted. Two genotyping methods, pulsed-field gel electrophoresis and infrequent-restriction-site PCR, were used to examine the isolates. A total of 12 genotypes were identified, and 2 predominant genotypes were found in 72 (82.8%) of the 87 isolates derived from all over the hospital. However, 63.9% of the isolates of the two genotypes were from neurology wards. A subsequent intervention by infection control personnel reduced the infection rate greatly. The number and proportion of the two predominant genotypes were significantly reduced among the 51 isolates collected in 2001 and 2002. Thus, a chronic and long-lasting epidemic of nosocomial UTIs caused by S. marcescens was identified and a successful intervention was carried out. Both a cautious review of laboratory and infection control data and an efficient genotyping system are necessary to identify such a cryptic epidemic and further contribute to the quality of patient care.  相似文献   
46.
An HIV-1 p24 antigen test involving signal amplification-boosted ELISA of heat-denatured plasma was evaluated prospectively in 55 patients whose viral RNA in plasma had previously been suppressed for at least 6 months under antiretroviral combination therapy. During a median follow-up of 504 days, CD4 counts increased by a median of 62 cells per year. By univariate and multivariate linear regression analysis, the level of p24 antigen as expressed by the absorbance/cutoff ratio was a significant inverse correlate of both the CD4 count in a sample (p =.013) and its annual change in a patient (p <.0001). The p24 antigen retained significance even among 48 individuals whose HIV-1 RNA, apart from occasional blips, remained below 400 copies/mL. Batch-wise retesting of 70 samples from 5 such patients with a further improved procedure showed measurable p24 antigen in all but 1 sample and an inverse correlation with both the CD4 count (p =.0331) and percentage (p <.0001), thus confirming the prospectively generated data. Comparison of p24 antigen and HIV-1 RNA concentrations indicate that the p24 antigen detected in these samples is not associated with viral RNA-containing particles and may originate from other compartments of virus expression.  相似文献   
47.
BACKGROUND: Meta-analysis and randomized clinical trial results reported in June 1998 indicated a significant reduction in perinatal HIV transmission rates among mothers undergoing a cesarean section (C-section). OBJECTIVE: The objective of this study was to examine recent trends in and factors associated with C-section deliveries among HIV-infected women in the United States. DESIGN: A multisite pediatric medical record review of a cohort of HIV-exposed and HIV-infected infants in the Pediatric Spectrum of HIV Disease (PSD) Cohort study (n = 6467) and the national Pediatric HIV/AIDS Reporting System (HARS) (n = 8,306) was conducted. SETTING/PATIENTS: All infants born between 1994 and 2000 to HIV-positive mothers referred to the PSD study or to a Pediatric HARS hospital or clinic site were enrolled. RESULTS: The proportion of deliveries by C-section was steady at about 20% from 1994 through June 1998. From July 1998 through December 2000, this proportion increased to 44% in the PSD study and to nearly 50% in the Pediatric HARS. On analysis by multiple logistic regression, delivery of infants by C-section was associated with the release of study results (OR = 2.83), delivery in four PSD sites in reference to Texas (OR: 2.02-1.43), having private medical care reimbursement (OR = 1.62), and having maternal prenatal care (OR = 1.43). CONCLUSIONS: The PSD and Pediatric HARS data demonstrate a sharp increase in C-section rates mainly among HIV-infected women in the United States after the release of the meta-analysis and randomized clinical trial results in 1998. This finding highlights the rapid impact of study results on obstetric practice. It underscores the critical role of prenatal care in offering perinatal interventions such as scheduled C-section when indicated to reduce the likelihood of HIV transmission.  相似文献   
48.
A组轮状病毒广州地方株VP7基因序列的比较分析   总被引:4,自引:0,他引:4  
目的 了解我国轮状病毒G1型广州地方株与标准株及北京G1型地方株VP7基因序列的差异,为我国轮状病毒疫苗的研制提供资料。方法 通过逆转录—聚合酶链反应(RT—PCR)获得了轮状病毒广州地方株R97—196 VP7全基因的cDNA片段,将其克隆入T—A克隆质粒pUCm—T中,构建成重组质粒pUCmT—VP7,对克隆的VP7基因进行序列测定。结果 该地方株的基因核苷酸全长为1062nt,读码框架和以往的研究一致,和北京G1型地方株173的VP7氨基酸序列具有高度同源性(98%),而与不同血清型标准株间则变异较大(73%—81%),氨基酸序列中存在的一些高变区和保守功能区与已报道的研究结果一致。从进化角度分析,与轮状病毒标准株Wa株,相距较远。结论 轮状病毒广州地方株R97—196 VP7基因片段属G1型,轮状病毒VP7基因的变异与地域有一定关系。  相似文献   
49.
In Italy, the prevalence of non-B HIV-1 subtypes ranges reportedly from 5.4% to 12.6%, yet there are no data on their circulation in prisons, where the prevalence of HIV infection is high. A retrospective study was conducted to evaluate the circulation of non-B subtypes and to characterize their determinants in five Italian prisons. To this end an aliquot of samples of blood was taken in the period 2001-2006 from all 262 HIV-positive inmates in whom antiretroviral treatment had failed. Complete HIV-1 PR and RT regions were sequenced for all samples and subjected to phylogenetic analysis; 250 (95.4%) sequences clustered with subtype B. The non-B subtype was found in 4% of Italian prison inmates and 16.7% of non-Italian prison inmates; the overall percentage increased from 1.8% for inmates infected in 1982-1990 to 4.4% in 1991-1999 and 21.9% in 2000-2006. Factors significantly associated with non-B subtypes were an exposure to other than injecting drug use and a first positive HIV test in 2000-2006. Non-B subtypes were distributed within five monophyletic clades. In all cases but one, it was possible to correlate the history of HIV-exposure to the origin of the clade, with high bootstrap values. In conclusion, although the sample may not be representative of the prison inmate population in Italy, the data suggest strongly that the circulation of non-B subtypes has apparently increased. Non-B subtypes were found to have been associated with heterosexual contact and time of the first HIV-positive test. Knowledge of the different subtypes circulating in prisons may be useful for tracking the epidemiology of HIV infection and for choosing antiretroviral therapy.  相似文献   
50.
The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points.  相似文献   
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