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1.
Neurosarcoma is a rare tumour originating from the sheath of peripheral nerves. Facial lesions have been reported in about 20 patients. We describe the MRI appearances of neurosarcoma with histological correlation in three patients. The lesions lay in the submandibular region, the left parapharyngeal space and the right orbit. MRI showed a well-defined mass with mixed components. The lesions were moderately heterogeneous on T1-weighted images in two cases and on T2-weighted images in all cases. Gadolinium enhancement occurred in all cases to variable degrees. In two cases, small high signal foci were seen on T2-weighted sequences. MRI appearances of neurosarcoma are not specific. Received: 3 September 1996 Accepted: 26 November 1996  相似文献   
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Considerable controversy exists as to whether Henoch-Sch?nlein purpura and Iga nephropathy are different clinical manifestations of the same disease or if, on the contrary, they are separate entities. We report on the development of Henoch-Sch?nlein purpura and IgA nephropathy in 2 members of the same family. Patient 1, a 63-year-old man, presented with purpura in the legs, abdominal pain, hematuria, renal failure and proteinuria. A biopsy of a purpuric skin lesion showed small-vessel vasculitis, and a renal biopsy showed diffuse proliferative glomerulonephritis with prominent IgA deposits, thus making the diagnosis of Henoch-Sch?nlein purpura. Serum IgA was increased. Patient 2, the 30-year-old son of patient 1, underwent renal biopsy for the investigation of microscopic hematuria and proteinuria. There was no history of skin rash, and serum creatinine was normal. A renal biopsy showed expansion of the mesangial matrix and marked IgA deposition. HLA typing confirmed that they shared a haplotype. HLA B35 or DR4 were absent. These results demonstrate that Henoch-Sch?nlein purpura and IgA nephropathy can possibly be genetically related and therefore support the notion that these two diseases probably share a common pathogenesis.  相似文献   
3.
It has been proposed that alcoholics may have a disrupted subjective sense of time. A review of empirical investigations of alcoholics' psychological time functioning is presented, attempting to carefully distinguish between the concepts of time perspective, time attitude, and time orientation. It is recognized that the label "alcoholic" is not a homogeneous diagnosis, and it is used here for individuals in treatment for problems related to alcohol abuse. Important questions raised by the previous investigations are listed along with speculations about the role of cognitive impairment in relation to time functioning of alcoholics. Suggestions are made for potential differential treatment according to the patients' time functioning as it relates to motivation, and for additional research needed in this area.  相似文献   
4.
This study was undertaken to investigate cyclooxygenase-2 (COX-2) expression in follicular cells of the human thyroid. COX-2 expression was studied immunohistochemically in a total of 174 samples. COX-2 immunoreactivity was confined to the cell cytoplasm with the nuclei remaining unlabelled. COX-2 expression was observed in five cases (17.2%) of normal follicular cells and in one case (16.6%) of solid cell nests. Follicular carcinoma expressed COX-2 more frequently than follicular adenoma (93.4% vs 21.1%) (p0.001). A higher percentage of cases of papillary microcarcinomas up-regulated COX-2 in comparison with all papillary carcinomas (p0.05). However, we could not establish any relationships among COX-2, patients ages or lymph node metastases in papillary carcinomas. COX-2 expression was found in 12 (92.3%) poorly differentiated carcinomas and in 13 (92.8%) undifferentiated carcinomas. We found that COX-2 is not always useful as a marker of malignancy. Our results suggest that COX-2 plays a role in progression of all thyroid carcinomas, but in papillary carcinomas, seems more important only in the early stages. COX-2 expression in the undifferentiated carcinoma deserves special consideration due to its prognosis and to the fact that selective COX-2 inhibitors were found to enhance tumour response to radiation in some studies.  相似文献   
5.
The TNF family ligand B cell-activating factor (BAFF, BLyS, TALL-1) is an essential factor for B cell development. BAFF binds to three receptors, BAFF-R, transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA), but only BAFF-R is required for successful survival and maturation of splenic B cells. To test whether the effect of BAFF is due to the up-regulation of anti-apoptotic factors, TACI-Ig-transgenic mice, in which BAFF function is inhibited, were crossed with transgenic mice expressing FLICE-inhibitory protein (FLIP) or Bcl-2 in the B cell compartment. FLIP expression did not rescue B cells, while enforced Bcl-2 expression restored peripheral B cells and the ability to mount T-dependent antibody responses. However, many B cells retained immaturity markers and failed to express normal amounts of CD21. Marginal zone B cells were not restored and the T-independent IgG3, but not IgM, response was impaired in the TACI-IgxBcl-2 mice. These results suggest that BAFF is required not only to inhibit apoptosis of maturating B cells, but also to promote differentiation events, in particular those leading to the generation of marginal zone B cells.  相似文献   
6.
Twins have always fascinated medical research even before the discovery of DNA and the understanding of the differences between identical and non‐identical twins. Dermatology with the benefit of being able to visualize phenotypes was one of the first specialities reporting on the fascinating concordance in identical (MZ) twins in the 1920’s. Over the last 20 years, the heritability of skin diseases using twins has been clearly demonstrated, across a wide variety of traits including melanoma, polymorphic light eruption, psoriasis, eczema and acne. Other rarer diseases have also been shown to have a significant genetic basis such as lupus, sarcoidosis and lichen sclerosus. Following evidence of heritability for many skin disease the next step was Genome‐Wide Association Studies (GWAS) which are uncovering new genes in large twin cohorts. The twin model is also ideal for the new field of epigenetics, investigating subtle differences in DNA methylation within discordant MZ pairs for a disease, as well as differences in CNVs. Twins are also valuable for examining differences in gene function via RNA expression in twins discordant for a skin trait or disease.  相似文献   
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Survivin, an inhibitor of apoptosis family molecule, has been proposed as a crucial intermediate in the signaling pathways leading to T‐cell development, proliferation, and expansion. However, the importance of survivin to T‐cell‐driven inflammatory responses has not been demonstrated. Here, we show that survivin transgenic mice exhibit an increased antigen‐driven Th2 lung inflammation and that constitutive expression of survivin reversed the defective lung inflammation even in the absence of OX40 costimulation. We found that OX40‐deficient mice were compromised in generating Th2 cells, airway eosinophilia, and IgE responses. In contrast, OX40‐deficient/survivin transgenic mice generated normal Th2 responses and exhibited strong lung inflammation. These results suggest that OX40 costimulation crucially engages survivin during antigen‐mediated Th2 responses. These findings also promote the notion that OX40 costimulation regulates allergic responses or lung inflammation by targeting survivin thereby enhancing T‐cell proliferation and resulting in more differentiated Th2 cells in the allergic inflammatory response.  相似文献   
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