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991.
Testicular seminoma is characterized by a prominent lymphoid infiltrate and an excellent prognosis. Cytotoxic T-lymphocytes (CTLs) infiltrating seminoma tumour nests constitute a major subset of the lymphoid infiltrate. The objective of this study was to determine whether CTLs express markers of cytotoxic potential and activity and whether the number of activated CTLs correlates with the extent of apoptosis in testicular seminomas, as opposed to non-seminomatous testicular germ cell tumours (NSTGCTs). Twenty cases of pure seminoma as well as 20 cases of NSTGCTs including 16 mixed germ cell tumours (MGCTs) were studied. Immunohistochemistry for the cytotoxic markers TIA-1 (cytotoxic potential) and granzyme B (cytotoxic activity) and the T-cell markers CD3 and CD8 was performed on formalin-fixed, paraffin-embedded sections. The apoptotic index (AI) was determined by the TUNEL method. The number of CD3(+), CD8(+), TIA-1(+), and granzyme B(+) cells in tumour cell nests was markedly increased in testicular seminomas, compared with NSTGCTs (p<0.01). Activated granzyme B(+) cells numbered 25.6+/-5.2 per high power field in seminomas and 8.9+/-3.2, 8.1+/-3.9, and 0.4+/-0.2 for embryonal carcinomas, yolk sac tumours, and immature teratomas, respectively. Double immunohistochemical staining for granzyme B and CD8 revealed that 82.6+/-8.5% of granzyme B-expressing cells were CD8(+). The tumour cell AI was significantly increased in embryonal carcinoma, compared with the seminoma, yolk sac tumour, and immature teratoma subgroups (6.7+/-1.3, 2.3+/-0.3, 3.0+/-1.1, and 2.3+/-1.1, respectively, p<0.001). TUNEL/CD3 double immunostaining revealed that a significant proportion of the apoptotic seminomatous tumour cells were in direct contact with one or more CD3(+) lymphocytes (47.2+/-6.2%). The number of activated granzyme B(+) CTLs showed a strong linear correlation with the AI in the seminoma group (r=0.71, p<0.0001) but not in other subgroups. TUNEL/granzyme B double immunolabelling revealed that a proportion of activated granzyme B(+) lymphocytes (20%) were often seen in close contact with apoptotic tumour cells. The presence of increased numbers of activated cytotoxic lymphocytes in testicular seminomas suggests that apoptotic tumour cell death in this neoplasm may be triggered by cytotoxic granule effectors. This phenomenon may be one of the key host immune mechanisms leading to the excellent prognosis in this tumour.  相似文献   
992.
Recently, the category of malignant fibrous histiocytoma (MFH) has been under discussion and new entities resembling MFH have appeared. To clarify the recent situation regarding MFH, we reassessed previously diagnosed MFH cases in accordance with the most up-to-date diagnostic criteria, which included allied tumors. We carefully reassessed 428 cases that had been diagnosed in our institute during the past 28 years. Moreover, we searched for clinicopathological prognostic factors among the cases that were finally diagnosed as MFH. Among the 428 cases, 138 cases had their diagnoses changed. The revised cases included 78 leiomyosarcomas (57%; ordinary leiomyosarcoma, 45 cases; pleomorphic leiomyosarcoma, 23 cases; myxoid leiomyosarcoma, 10 cases), 12 liposarcomas (9%; pleomorphic liposarcoma, 11 cases; dedifferentiated liposarcoma, one case), seven dermatofibrosarcoma protuberans (5%), six unclassified sarcomas (4%), five primary or metastatic carcinomas (4%), four low-grade fibromyxoid sarcomas (3%), four inflammatory myofibroblastic tumors (3%), three rhabdomyosarcomas (2%), three malignant peripheral nerve sheath tumors (2%), three acral myxoinflammatory fibroblastic sarcomas (2%) and two atypical fibroxanthomas (1.5%). Among the 1974 soft tissue sarcomas registered in our institute, MFH (428 cases) had been the most common sarcoma, followed by liposarcoma, leiomyosarcoma and rhabdomyosarcoma. However, after reassessment, leiomyosarcoma proved to be the most common soft tissue sarcoma (322 cases), followed by 290 MFH, 273 liposarcomas and 202 rhabdomyosarcomas. Among these 290 cases finally diagnosed as MFH, survival data were available in 189 cases. Tumor location in the abdominal cavity, the retroperitoneum or the head and neck (P = 0.0024), tumor size of 5 cm or more (P < 0.0001), deep tumor location (P < 0.0001), high histological grade (grade 3) based on the French Federation of Cancer Centers' grading system (P = 0.0007), and high stage (stage III or IV) based on the American Joint Committee on Cancer (AJCC) staging system (P < 0.0001) were significantly worse prognostic factors by univariate analysis. In multivariate analysis, deep tumor location and high AJCC stage were independent adverse prognostic factors. We conclude that leiomyosarcoma is the most important differential diagnosis for MFH, especially pleomorphic leiomyosarcoma from storiform-pleomorphic type and myxoid leiomyosarcoma from myxoid type. Tumor depth and AJCC stage are the most important predictive prognostic factors in MFH.  相似文献   
993.
Desmin‐related myopathy is a familial or sporadic disease characterized by skeletal muscle weakness and cardiomyopathy as well as the presence of intracytoplasmic aggregates of desmin‐reactive material in the muscle cells. Previously, two kinds of deletions and eight missense mutations have been identified in the desmin gene and proven to be responsible for the disorder. The present study was conducted to determine structural and functional defects in a pathogenic desmin variant that caused a disabling disorder in an isolated case presenting with distal and proximal limb muscle weakness and cardiomyopathy. We identified a novel heterozygous Q389P desmin mutation located at the C‐terminal part of the rod domain as the causative mutation in this case. Transfection of desmin cDNA containing the patient’s mutation into C2.7, MCF7, and SW13 cells demonstrated that the Q389P mutant is incapable of constructing a functional intermediate filament network and has a dominant negative effect on filament formation. We conclude that Q389P mutation is the molecular event leading to the development of desmin‐related myopathy. Hum Mutat 18:388–396, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
994.
A HeLa cell line stably expressing the enhanced green fluorescence protein (EGFP) gene, interrupted by the HBB IVS2‐654 intron, was studied without treatment and after treatment with a single standard dose of 15 μM of N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG). This assay was done in order to prove that such a construct can revert by a variety of mechanisms and that it produces a visible phenotype, i.e., green fluorescence. The system permits visual detection of living mutant cells among a background of non‐mutant cells and does not require a selective medium. The results show that the construct reverts by large deletions (–62, –100, and –162 bp), small insertions (+4 bp), small rearrangements (19 bp duplication), base substitutions at purines (G652, G653, A655, G579), and a pyrimidine (T654) between nucleotide positions 579 and 837. Splice‐site mutations were recovered, and some of the mechanisms underlying these mutations are discussed. Because of the ease of detection of revertant cells under fluorescent light and the wide variety of mutations that can be recovered, further development of this system could make it a useful new mammalian cell mutagenicity assay. Hum Mutat 18:526–534, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
995.
The common cytokine receptor gamma chain (gamma(c)) is an essential receptor component for IL-2, IL-4, IL-7, IL-9 and IL-15, and thereby gamma(c)-deficient mice exhibit impaired T cell and B cell development. The Janus family tyrosine kinase 3 (Jak3) is known to be associated with gamma(c), and the reported phenotypes of gamma(c)-deficient (gamma(c)(-)) and Jak3-deficient (Jak3(-)) mice are similar, indicating that Jak3 is an essential transducer of gamma(c)-dependent signals. Nevertheless, certain differences have been suggested related to the range of actions of gamma(c) and Jak3. To clarify whether gamma(c)-dependent cytokines can partially transduce their signals without Jak3, we compared lymphocyte development in gamma(c)(-), Jak3(-), and gamma(c) and Jak3 double-deficient (gamma(c)(-)Jak3(-)) mice in the same genetic background. With the exception that T and B cells in Jak3(-) mice express high levels of gamma(c), the defects in thymocyte and peripheral T cell and B cell development are indistinguishable among gamma(c)(-), Jak3(-) and gamma(c)(-)Jak3(-) mice. Interestingly, although Bcl-2 induction was previously suggested to be Jak3-independent, IL-7 cannot induce Bcl-2 expression in CD4 single-positive (SP) thymocytes in either gamma(c)(-) or Jak3(-) mice nor can IL-7 rescue CD4 SP thymocytes from dexamethasone-induced cell death in gamma(c)(-) or Jak3(-) mice. These results indicate that Jak3 is absolutely essential for gamma(c)-dependent T cell and B cell development, and for gamma(c)-dependent prevention of thymocyte apoptosis.  相似文献   
996.
目的:建立旋髂深动脉及穿支的数字化可视模型,为临床上旋髂深动脉穿支骨皮瓣的设计与安全截取提供形态学基础。方法:2具新鲜男尸,分别采用羧甲基纤维素/氧化铅水凝胶及明胶/氧化铅行一次性全身动脉造影,并进行连续螺旋CT扫描,运用Mimics软件,在计算机上对腰区相关重要结构进行计算机三维重建和立体显示。结果:该数字化可视模型能够清晰显示髋骨、髂外动脉、旋髂深动脉及其供血皮瓣的形态、位置及毗邻关系,并可任意方向的旋转观察。结论:重建的三维模型可以提供正常腰区皮瓣的三维动态解剖,为临床术前皮瓣设计提供了直观的数字化解剖依据。  相似文献   
997.
In some autosomal imbalance syndromes an additional imbalance interferes with the occurrence of the anomalies typical of the syndrome itself. For example, polydactyly was found in patients with “pure” del(3p) more frequently (11/23) than in patients where these deletions were associated with different partial trisomies (2/28). The opposite situation was shown in del(7q) syndrome where various defects of the holoprosencephalic group were found to be rarer in patients with “pure” deletions, than in cases with simultaneous occurrence of various partial trisomies. It suggests the importance of gene interaction in determining the phenotypic picture of autosomal imbalance syndromes. © 1993 Wiley-Liss, Inc.  相似文献   
998.
Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied MHC class II molecules and invariant chain inducibility on four class II negative mouse pro- B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative. As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only. These data suggest that the induction of class II and invariant-chain genes are subject to regulation throughout B-cell differentiation.  相似文献   
999.
Two adapter proteins, Grb2 and Shc, have recently been implicated in the transmission of activation signals from the stimulated T cell receptor to Ras. We show here that in vitro stimulation of mouse splenic T cells with crosslinked anti-CD3 antibody leads within 30 s to phosphorylation of both Grb2 and Shc. Treatment with crosslinked anti-CD45 antibody leads to phosphorylation of Grb2 and also to a slight retardation in the mobility of this protein in an SDS polyacrylamide gel; both changes are seen within 30 s of crosslinking. Crosslinked anti-CD4 antibody leads to phosphorylation of Shc and to the phosphorylation of a 30-kDa protein that cross-reacts with anti-Grb2 antibodies. Aging leads to a decline in CD3-stimulated phosphorylation of Shc (but not Grb2), and to an increase in CD4-stimulated phosphorylation of Grb2, Shc, and the 30-kDa Grb2-like protein. Increased tyrosinephosphorylation of Grb2 after exposure to either anti-CD3 or anti-CD45 suggests that Grb2 may be a common substrate for both CD3-linked kinases and the CD45 phosphatase. The differences between T cells from young and old mice suggest that aging may lead to a set of alterations in kinase/substrate coupling that contribute to immune dysfunction in the elderly, and that activation of the Ras pathway might be impaired by aging in T lymphocytes.  相似文献   
1000.
Background: Despite years of research, the treatment of acute kidney injury (AKI) remains a significant challenge. Animal studies presented causal links between elevated regulatory T cell (Treg) response and better prognosis in AKI. Previous studies in mice and humans showed that TIM-3+ Treg cells were more potent than TIM-3- Treg cells. In this study, we investigated the role of TIM-3 in Treg in AKI patients.

Methods: Peripheral blood from AKI patients and healthy controls were gathered, and TIM-3+ Treg subset was examined.

Results: Compared to healthy controls, the AKI patients presented a significant upregulation in the frequency of circulating CD4+CD25+ T cells; however, the majority of this increase was from the CD4+CD25+TIM-3- subset, and the frequency of CD4+CD25+TIM-3+ T cells was downregulated in AKI patients. In both healthy controls and AKI patients, the CD4+CD25+TIM-3+ T cells expressed higher levels of Foxp3, and were more potent at expressing LFA-1, LAG-3, CTLA-4, IL-10 and TGF-β. In addition, the CD4+CD25+TIM-3+ T cells from both healthy controls and AKI patients presented higher capacity to suppress CD4+CD25- T cell proliferation than the CD4+CD25+TIM-3- T cells. Interestingly, the total CD4+CD25+ T cells from AKI patients presented significantly lower inhibitory capacity than those from healthy controls, indicating that the low frequency of CD4+CD25+TIM-3+ T cells was restricting the efficacy of the Treg responses in AKI patients.

Conclusions: We demonstrated that TIM-3 downregulation impaired the function of Treg cells in AKI. The therapeutic potential of CD4+CD25+TIM-3+ T cells in AKI should be investigated in future studies.  相似文献   

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