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101.
The aim of this study was to define the histological spectrum, frequency and significance of nonconventional tumour cells in clear cell renal cell carcinomas (CCRCC). Fifty‐one totally sampled CCRCC were studied histologically to evaluate the spectrum of cell morphology variability, its frequency and significance, and their correlation with tumour grade and stage, and other histological parameters of aggressive behaviour like necrosis. Aside from conventional clear/eosinophilic granular cells, three additional cellular types were identified and considered in this study: small clear cells, syncytial cells and rhabdoid cells. Small clear cells were detected in 11 cases (21.5%), syncytial cells in 8 (15.6%) and rhabdoid cells in 5 (9.8%). The presence of syncytial and rhabdoid cells statistically correlated with grade (p = 0.003 and p = 0.006) and stage (p = 0.049 and p = 0.05) in CCRCC. Necrosis correlated with stage (p = 0.018) and grade (p = 0.004), but not with syncytial, rhabdoid or small clear cells. The presence of syncytial and rhabdoid cells in CCRCC is a relatively frequent event that significantly correlates with high‐grade tumours and high stage status.  相似文献   
102.
To examine the significance of intratumor genetic heterogeneity (ITGH) of the androgen receptor (AR) gene in breast cancer, patient‐matched samples of laser capture microdissected breast tumor cells, adjacent normal breast epithelia cells, and peripheral blood leukocytes were sequenced using a novel next generation sequencing protocol. This protocol measured the frequency of distribution of a variable AR CAG repeat length, a functional polymorphism associated with breast cancer risk. All samples exhibited some degree of ITGH with up to 30 CAG repeat length variants identified. Each type of tissue exhibited a different distribution profile of CAG repeat lengths with substantial differences in the frequencies of zero and 18–25 CAG AR variants. Tissue differences in the frequency of ARs with each of these CAG repeat lengths were significant as measured by paired, twin t‐tests. These results suggest that preferential selection of 18–25 CAG repeat length variants in breast tumors may be associated with breast cancer, and support the observation that shorter CAG repeats may protect against breast cancer. They also suggest that merely identifying variant genes will be insufficient to determine the critical mutational events of oncogenesis, which will require measuring the frequency of distribution of mutations within cancerous and matching normal tissues.  相似文献   
103.
Neutrophil accumulation in the lower respiratory tract of patients with fibrosing alveolitis is thought to be facilitated by IL-8, a neutrophil chemoattractant primarily secreted by mononuclear phagocytes. The aims of this study were: (i) to explore IL-8 secretion by lung and blood mononuclear phagocytes in subjects with cryptogenic fibrosing alveolitis, systemic sclerosis with and without fibrosing alveolitis, sarcoidosis and normal individuals; (ii) to examine IL-8 secretory heterogeneity in alveolar macrophages and peripheral blood monocytes; and (iii) to correlate alveolar macrophage phenotypic profile to IL-8 secretion. We observed that more monocytes secreted IL-8 than autologous macrophages and that there was heterogeneity in the in vitro IL-8 secretion by alveolar macrophages and peripheral blood monocytes. IL-8 secretion by alveolar macrophages was significantly higher in subjects with fibrosing alveolitis compared with subjects without fibrosing alveolitis, due to a higher percentage of IL-8-secreting alveolar macrophages in the fibrotic group both in the absence (P<0.002) and presence of lipopolysaccharide (LPS) (P<0.04) and correlated with bronchoalveolar lavage neutrophil percentage. Using the MoAbs RFD1, RFD7 and RFD9, that distinguish subsets of alveolar macrophages, we have been able to identify associations between secretion of IL-8 and smaller cells and the cells identified by the MoAb RFD7. In situ hybridization of the bronchoalveolar lavage cell population revealed that alveolar macrophages are the predominant source of IL-8 in the lung. We conclude that there is an increased number of IL-8-secreting alveolar macrophages in the lungs of patients with fibrosing alveolitis, and IL-8 secretion by these cells is associated with specific phenotypic profile expression.  相似文献   
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106.
《Diagnostic Histopathology》2022,28(11):493-500
After decades of relative stagnation lung cancer is emerging as a disease type where rapid progress is being made in diagnosis and therapy, as well as in our understanding of disease biology. Much of this progress is of immediate impact to diagnosticians, and more is likely to affect diagnostic practice in the near future. In this review we seek to briefly summarize several key areas of active research of immediate or probable imminent value to trainee and consultant pulmonary pathologists alike. We cover some major changes in tumour classification, grading, and patient stratification, as well as considering the state of the art in machine-assisted interpretation of lung cancer histology, and the use of genetically modified lung cancer models.  相似文献   
107.
Microcephaly is a frequent feature of neurodevelopmental disorders (NDDs). Our study presents the heterogeneous spectrum of genetic disorders in patients with microcephaly either in isolated form or in association with other neurological and extra-neural abnormalities. We present data of 91 patients from 87 unrelated families referred to our clinic during 2016–2020 and provide a comprehensive clinical and genetic landscape in the studied cohort. Molecular diagnosis using exome sequencing was made in 45 families giving a yield of 51.7%. In 9 additional families probable causative variants were detected. We identified disease causing variations in 49 genes that are involved in different functional pathways Among these, 36 had an autosomal recessive pattern, 8 had an autosomal dominant pattern (all inherited de novo), and 5 had an X-linked pattern. In 41 probands where sequence variations in autosomal recessive genes were identified 31 were homozygotes (including 16 from non-consanguineous families). The study added 28 novel pathogenic/likely pathogenic variations. The study also calls attention to phenotypic variability and expansion in spectrum as well as uncovers genes where microcephaly is not reported previously or is a rare finding. We here report phenotypes associated with the genes for ultra-rare NDDs with microcephaly namely ATRIP, MINPP1, PNPLA8, AIMP2, ANKLE2, NCAPD2 and TRIT1.  相似文献   
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109.
Population‐based genetic association analysis may suffer from the failure to control for confounders such as population stratification (PS). There has been extensive study on the influence of PS on candidate gene‐disease association analysis, but much less attention has been paid to its influence on marker‐disease association analysis. In this paper, we focus on the Pearson χ2 test and the trend test for marker‐disease association analysis. The mean and variance of the test statistics are derived under presence of PS, so that the power and inflated type I error rate can be evaluated. It is shown that the bias and the variance distortion are not zero in the presence of both PS and penetrance heterogeneity (PH). Unlike candidate gene‐disease association analysis, when PS is present, the bias is not zero no matter whether PH is present or not. This work generalises the published results, where only the fully recessive penetrance model is considered and only the bias is calculated. It is shown that candidate gene‐disease association analysis can be treated as a special case of marker‐disease association analysis. Consequently, our results extend previous studies on candidate gene‐disease association analysis. A simulation study confirms the theoretical findings.  相似文献   
110.
Chen JM, Férec C, Cooper DN. Revealing the human mutome. The number of known mutations in human nuclear genes, underlying or associated with human inherited disease, has now exceeded 100,000 in more than 3700 different genes (Human Gene Mutation Database). However, for a variety of reasons, this figure is likely to represent only a small proportion of the clinically relevant genetic variants that remain to be identified in the human genome (the ‘mutome’). With the advent of next‐generation sequencing, we are currently witnessing a revolution in medical genetics. In particular, whole‐genome sequencing (WGS) has the potential to identify all disease‐causing or disease‐associated DNA variants in a given individual. Here, we use examples of recent advances in our understanding of mutational/pathogenic mechanisms to guide our thinking about possible locations outwith gene‐coding sequences for those disease‐causing or disease‐associated variants that are likely so often to have been overlooked because of the inadequacy of current mutation screening protocols. Such considerations are important not only for improving mutation‐screening strategies but also for enhancing the interpretation of findings derived from genome‐wide association studies, whole‐exome sequencing and WGS. An improved understanding of the human mutome will not only lead to the development of improved diagnostic testing procedures but should also improve our understanding of human genome biology.  相似文献   
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