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61.
The genetic epidemiology of Trichomonas vaginalis is poorly understood at present. The recent release of the organism's genome sequence opens the way to investigation of polymorphic markers allowing strain identification. We here report a preliminary analysis of microsatellite loci in T. vaginalis and show that this approach holds promise for future studies of infection transmission and organism diversity.  相似文献   
62.
We assessed the diversity and distribution of Trypanosoma cruzi discrete typing units (DTU) in Triatoma infestans populations and its association with local vector-borne transmission levels at various geographic scales. At a local scale, we found high predominance (92.4%) of TcVI over TcV in 68 microscope-positive T. infestans collected in rural communities in Santiago del Estero province in northern Argentina. TcV was more often found in communities with higher house infestation prevalence compatible with active vector-borne transmission. Humans and dogs were the main bloodmeal sources of the TcV- and TcVI-infected bugs. At a broader scale, the greatest variation in DTU diversity was found within the Argentine Chaco (227 microscope-positive bugs), mainly related to differences in equitability between TcVI and TcV among study areas. At a country-wide level, a meta-analysis of published data revealed clear geographic variations in the distribution of DTUs across countries. A correspondence analysis showed that DTU distributions in domestic T. infestans were more similar within Argentina (dominated by TcVI) and within Bolivia (where TcI and TcV had similar relative frequencies), whereas large heterogeneity was found within Chile. DTU diversity was lower in the western Argentine Chaco region and Paraguay (D = 0.14–0.22) than in the eastern Argentine Chaco, Bolivia and Chile (D = 0.20–0.68). Simultaneous DTU identifications of T. cruzi-infected hosts and triatomines across areas differing in epidemiological status are needed to shed new light on the structure and dynamics of parasite transmission cycles.  相似文献   
63.
目的了解并掌握塔里木河流域新疆出血热自然疫源地生态系统主要宿主和媒介的群落构成,及其与新疆出血热流行的相关性。方法根据塔里木河流域地理环境特征,在上、中、下游3个区段设立调查研究样方,采集家畜、啮齿动物和蜱类样本,采用生态学方法分析不同生态景观下宿主和媒介的群落结构组成和特征,检测蜱类样本的新疆出血热病毒携带率和家畜抗体携带率,统计分析流行病学的相关性。结果塔里木河流域新疆出血热自然疫源地啮齿动物和蜱类群落组成简单,啮齿动物7种,以子午沙鼠为主,占73.6%,蜱类3种,以亚洲璃眼蜱为主,占98.4%以上:不同地理生态景观上,干旱、半干旱的沙质盐碱地是亚洲璃眼蜱和啮齿动物分布的最优生态景观;空间分布上,亚洲璃眼蜱在优生景观中的数量由上游至下游逐步增加的变化趋势一致,游离蜱指数分别为37.0、44.7和64.7;塔里木河流域上、中、下游3个区段羊血清抗新疆出血热病毒抗体阳性率由13.2%增加至43.1%,自然界中亚洲璃眼蜱病毒分离率由零增加至6.9%,亚洲璃眼蜱指数和羊血清CCHFV(克里米亚刚果出血热病毒)阳性率呈正相关(r=0.992)。结论塔里木河流域新疆出血热自然疫源地呈现丰富的多样性,其自然界新疆出血热流行强度与疫源地宿主媒介及植被构成的丰富度密切相关,可因自然界中亚洲璃眼蜱指数的不同分为不同的流行区。  相似文献   
64.
ObjectiveWomen and minorities remain under-represented in academic vascular surgery. This under-representation persists in the editorial peer review process which may contribute to publication bias. In 2020, the Journal of Vascular Surgery (JVS) addressed this by diversifying the editorial board and creating a new Editor of Diversity, Equity, and Inclusion (DEI). The impact of a DEI editor on modifying the output of JVS has not yet been examined. We sought to determine the measurable impact of a DEI editor on diversifying perspectives represented in the journal, and on contributing to changes in the presence of DEI subject matter across published journal content.MethodsThe authorship and content of published primary research articles, editorials, and special articles in JVS were examined from November 2019 through July 2022. Publications were examined for the year prior to initiation of the DEI Editor (pre), the year following (post), and from September 2021 to July 2022, accounting for the average 47-week time period from submission to publication in JVS (lag). Presence of DEI topics and women authorship were compared using χ2 tests.ResultsDuring the period examined, the number of editorials, guidelines, and other special articles dedicated to DEI topics in the vascular surgery workforce or patient population increased from 0 in the year prior to 4 (16.7%) in the 11-month lag period. The number of editorials, guidelines, and other special articles with women as first or senior authors nearly doubled (24% pre, 44.4% lag; P = .31). Invited commentaries and discussions were increasingly written by women as the study period progressed (18.7% pre, 25.9% post, 42.6% lag; P = .007). The number of primary research articles dedicated to DEI topics increased (5.6% pre, 3.3% post, 8.1% lag; P = .007). Primary research articles written on DEI topics were more likely to have women first or senior authors than non-DEI specific primary research articles (68.0% of all DEI vs 37.5% of a random sampling of non-DEI primary research articles; P < .001). The proportion of distinguished peer reviewers increased (from 2.8% in 2020 to 21.9% in 2021; P < .001).ConclusionsThe addition of a DEI editor to JVS significantly impacted the diversification of topics, authorship of editorials, special articles, and invited commentaries, as well as peer review participation. Ongoing efforts are needed to diversify subject matter and perspective in the vascular surgery literature and decrease publication bias.  相似文献   
65.
ObjectiveGiven the diversity of populations that modern healthcare professionals treat, there has been an increasing call for academic medical centers to ensure that they themselves are diverse and inclusive. Historically, this has been measured by the composition of the workforce in terms of protected categories such as race/ethnicity, gender, and disability. However, these broad categories have only poorly reflected the actual ability of organizations to engage with a diverse workforce and patient population. The diversity and engagement survey (DES) is a specifically constructed and validated instrument designed to measure the integration of diversity, equity, and inclusion (DEI) within academic medical centers. The goal of the present study was to use the DES with vascular surgery program directors, to determine the predictors of low DEI in vascular surgery training programs.MethodsAn anonymous electronic survey was sent to all program directors and assistant program directors of vascular surgery training programs (residencies and fellowships) in the United States (n = 280). The survey consisted of 18 sections with 53 questions regarding details of the respondent, demographics, programmatic information, including information on faculty and trainee diversity, the resources available to enhance DEI within the program, institutional attitudes toward employees, and the DES itself. The total score from the DES section was used to the stratify institutions, which were classified as low DEI if in the bottom 25% percentile of the overall scores or as high DEI if scoring higher. Univariate analysis was used to determine whether any important differences were present in the demographics or survey responses between the institutions scoring as low vs high DEI. Multivariate logistic regression was also performed using the demographic variables and responses to the survey questions to determine their relationship to DEI status.ResultsThere were a total of 102 complete responses to the survey (36.4% response rate). The proportion of women was higher (66.67%) than the men (33.30%) in the low DEI cohort, although women were only 28.4% of the overall cohort. A statistically significant difference was found between the high and low DEI institutions in the proportion of those who had responded yes, no, or preferred not to disclose whether they had experienced discrimination or hurtful comments (P < .001) with 71% of the respondents in the low DEI institutions reporting this experience compared with only 11% in high DEI institutions. Multivariate analysis also demonstrated that non-male gender (odds ratio, 5.10; P = .034) and experiences of discrimination (odds ratio, 6.51; P = .024) were associated with low DEI institutions.ConclusionsNon-male program directors and those who had experienced discrimination at their institution were significantly more likely to find that their institution had low DEI.  相似文献   
66.
Three hundred and twenty endophytic actinobacterial strains were isolated from psammophytes collected from Taklamakan Desert and identified. Among them, three strains already had been identified as new species of two genera and sixteen isolates showed relatively low 16S rRNA similarities < 98.6% to validly described species. Seventy-five of the isolates were selected as representative strains to screen antibacterial activity and mechanism. Forty-seven strains showed antagonistic activity against at least one of the indicator bacteria. Two Streptomyces strains produced bioactive compounds inducing DNA damage, and two Streptomyces strains produced bioactive compounds with inhibitory activity on protein biosynthesis. Notably, the strain Streptomyces sp. 8P21H-1 that demonstrated both strong antibacterial activity and inhibitory activity on protein biosynthesis was prioritized for exploring new antibiotics. Under the strategy of integrating genetics-based discovery program and MS/MS-based molecular networking, two new streptogramin-type antibiotics, i.e., acetyl-griseoviridin and desulphurizing griseoviridin, along with known griseoviridin, were isolated from the culture broth of strain 8P21H-1. Their chemical structures were determined by HR-MS, and 1D and 2D NMR. Desulphurizing griseoviridin and griseoviridin exhibited antibacterial activities by inhibiting translation.  相似文献   
67.
Devi NP  Jauhari RK 《Acta tropica》2008,105(3):249-252
An investigation on the occurrence of snails in the water bodies of five selected sites i.e., Khed, Chiplun, Ratnagiri, Parchuri and Gimvi of district Ratnagiri, Maharashtra (India) was made during April-May 2006. The study revealed occurrence of nine species of snails viz., Indoplanorbis exustus, Lymnaea luteola, L. acuminata, Paludomus obesus, Ferrissia tenuis, Thiara (Melanoides) tuberculata, Bellamya bengalensis, B. dissimilis and Pila globosa, besides some species of bivalves. I. exustus was the most common species by occurrence in all the selected localities and next to it was L. luteola followed by T. tuberculata, B. bengalensis and B. dissimilis, in succession. Infection with liverfluke and amphistome cercariae was found in most of the collected snail species except P. globosa. However, the Schistosome infection has been reported only in I. exustus and L. luteola. The rice fields, streams and riverbeds shared most abundance of snails whereas those collected from rice fields shedded highest number of cercariae.  相似文献   
68.
69.
The salivarius group of streptococci is of particular importance for humans. This group consists of three genetically similar species, Streptococcus salivarius, Streptococcus vestibularis and Streptococcus thermophilus. S. salivarius and S. vestibularis are commensal organisms that may occasionally cause opportunistic infections in humans, whereas S. thermophilus is a food bacterium widely used in dairy production. We developed Multilocus sequence typing (MLST) and comparative genomic analysis to confirm the clear separation of these three species. These analyses also identified a subgroup of four strains, with a core genome diverging by about 10%, in terms of its nucleotide sequence, from that of S. salivarius sensu stricto. S. thermophilus species displays a low level of nucleotide variability, due to its recent emergence with the development of agriculture. By contrast, nucleotide variability is high in the other two species of the salivarius group, reflecting their long-standing association with humans. The species of the salivarius group have genome sizes ranging from the smallest (∼1.7 Mb for S. thermophilus) to the largest (∼2.3 Mb for S. salivarius) among streptococci, reflecting genome reduction linked to a narrow, nutritionally rich environment for S. thermophilus, and natural, more competitive niches for the other two species. Analyses of genomic content have indicated that the core genes of S. salivarius account for about two thirds of the genome, indicating considerable variability of gene content and differences in potential adaptive features. Furthermore, we showed that the genome of this species is exceptionally rich in genes encoding surface factors, glycosyltransferases and response regulators. Evidence of widespread genetic exchanges was obtained, probably involving a natural competence system and the presence of diverse mobile elements. However, although the S. salivarius strains studied were isolated from several human body-related sites (all levels of the digestive tract, skin, breast milk, and body fluids) and included clinical strains, no genetic or genomic niche-specific features could be identified to discriminate specific group.  相似文献   
70.
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