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41.
Human longevity seems to be directly correlated with optimal functioning of the immune system, suggesting that some genetic determinants of longevity might reside in those polymorphisms for the immune system genes that regulate immune responses, in particular cytokine gene polymorphisms. In fact, modification of cytokine network is a constant report in studies on age related modification of immune response. Moreover cytokine polymorphisms studies are indicating their involvement in the reshaping of cytokines network as an integral part of the scenario related to a successful ageing. A particular role might be attributed to the influence of cytokine polymorphisms on the efficiency of immune response against infectious diseases that have been the principal selection in oldest old. Here are reported data on the evaluation of the frequency of the functional polymorphisms at genes coding for TNF-alpha (-308G-->A) and IL-10 (-1082G-->A), analysed by ARMS-PCR, in a group of Sicilian patients affected by chronic lung tuberculosis (TBC) compared to that from a group of healthy individuals living in the same region. Data obtained demonstrated a reduction of -308GG TNF homozygous individuals in TBC affected subject group. In the same group a reduction of IL-10 -1082A/* carriers was found. Our results seem to suggest that multiple genetic traits may affect the capacity to cope with an infectious agents and this might predispose to an overt disease. Moreover these data are in agreement with previous reports suggesting that a balanced interaction among pro- and anti-inflammatory molecules it is a key point for conditioning the life span expectancy.  相似文献   
42.
Serum and erythrocyte levels of the polyamines spermine, spermidine and putrescine, as well as ornithine decarboxylase in erythrocytes, were studied in patients with different neoplasms (breast, lung and colon cancer) and in those with a nonmalignant proliferative disease (familial polyposis). The blood levels of polyamines and the spermine/putrescine ratio were significantly higher in all tumors and in nonmalignant colon polyposis. In erythrocyte ornithine decarboxylase activity, spermine and spermidine levels, as well as spermidine/putrescine and spermine/putrescine ratios showed a significant decrease after surgery and chemotherapy. Our data suggest that high levels of blood polyamines and erythrocyte ornithine decarboxylase activity are related to cell proliferation and cancer treatment, but that levels of polyamines in serum and erythrocytes are still significantly high after cancer treatment and are similar to those in polyposis disease. Polyamines are related to nuclear activity during differentiation; therefore, the altered turnover of polyamines could be a sign of abnormal nuclear function. Since polyamines stimulate protooncogene expression, their high levels could be considered an important cofactor in malignant cell transformation.  相似文献   
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44.
The parabrachial nucleus (PBN) plays important roles in numerous autonomic functions and in pain modulation. In different animal species, three main regions of the PBN have been identified: the m-PB, the l-PB, and the Kolliker-Fuse nucleus (KF). The KF has not been identified in humans. The present study used Nissl and Golgi-Cox material and morphoquantitative methods to investigate the cytoarchitectural organization of the adult human PBN, paying particular attention to neuronal features endowed with functional significance, i. e. the arborization of the neurons. The PBN neuron population is made up of elements which are heterogeneous in size, shape and dendritic arborization, and grouped into two regions, the lateral and medial PBN (l- and m-PB). It has been suggested that some large sized neurons located in the ventral region of the m-PB might be the counterpart of the KF. In the m-PB the fusiform neurons are the most numerous cells; in the l-PB the multipolar neurons prevail, and are particularly numerous in the dorsal l-PB. Since the dendritic arborization is generally the main target of afferent projections to a neuron, it is possible that the l-PB, and in particular its dorsal region, might be the main site for the endings of afferences to the human PBN.  相似文献   
45.

Aim  

To investigate the subjective evaluation of an intensive rehabilitation programme and outcomes by people with Huntington’s disease (HD) and their caregivers.  相似文献   
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47.
During the hydrogenolytic removal of the benzyl ester from the pentapeptide Boc-Asp(OBzl)-Ala-Phe-Ile-Gly-OEt, either with hydrogen gas or ammonium formate in the presence of palladium-on-charcoal as catalyst, variable amounts (5–30%) of an unexpected by-product were always obtained. The compound was eventually identified as Boc-Asc-Ala-Phe-Ile-Gly-OEt (Asc = aminosuccinyl). The application of field desorption mass spectrometry as a diagnostic tool is reported. The study of this side reaction, carried out on the pentapeptide and two other dipeptide models, showed that: 1) palladium-on-charcoal may induce Asc formation; 2) the contemporary presence of the catalyst and a base (even in trace amounts) greatly increases the by-product formation; 3) the side reaction is sequence and solvent dependent; 4) the Asc formation is completely prevented by adding a few equivalents of acetic or formic acid. Some mechanistic considerations are also reported.  相似文献   
48.
BACKGROUND: Secreted protein acidic and rich in cysteine (SPARC) is a glycoprotein that mediates cell-matrix interactions. In adults, its expression is mostly limited to tissue undergoing remodeling. During the development of Cyclosporin A (CsA)-induced gingival overgrowth (GO) a remodeling of the connective compartment occurs. By contrast, clinical trials showed that FK506 is not related to GO. SPARC expression and its involvement in GO is unknown. Our aim was, therefore, to analyze the effect of CsA and FK506 on SPARC gene expression. METHODS: Cultured human gingival fibroblasts were incubated with CsA, FK506 or with their vehicle (VH) for 24, 48 and 72 h. SPARC gene expression was determined by RT-PCR. RESULTS: SPARC mRNA levels tended to increase 72 h after CsA treatment, whilst they are undetectable in FK506-treated fibroblasts, compared to VH. CONCLUSION: This gene expression profile is consistent with the involvement of SPARC in the mechanisms leading to the development of CsA-induced GO. By contrast, the undetectable SPARC mRNA levels in FK506-treated fibroblasts suggest that FK506 may be associated with a role of ECM stabilization, that does not induce GO.  相似文献   
49.
An association between Graves' disease (GD) and chronic hepatitis C (C-HC) has been observed both in the presence and the absence of recombinant interferon-alpha (rIFN-alpha) treatment. rIFN-alpha-induced GD is characterized by suppressed thyroid-stimulating hormone levels; normal or elevated free triiodothyronine (FT3) and free thyroxine (FT4) values; the presence of thyroid peroxidase antibodies, antithyroglobulin antibodies, and thyroid receptor antibodies; and high iodine thyroid uptake. In contrast, GD developed during C-HC without rIFN-alpha is less clearly defined. In this study, we examined two groups of patients: group A, 28 patients with C-HC treated with rIFN-alpha who developed GD after 1 to 9 months, and group B, 10 patients with C-HC who developed GD without a previous rIFN-alpha treatment. At the time of GD, both groups started methimazole therapy; thyroid function was reevaluated after 3, 6, 9, and 12 months. Group A patients continued IFN. After 12 months, all patients of group A were euthyroid, and 21 of them (75%) had already stopped methimazole treatment, whereas all patients of group B were euthyroid and only 2 (20%) had stopped methimazole. In conclusion, the data show a better course of GD, with a more precocious and significantly higher number of recoveries in patients with rIFN-alpha-induced GD than in rIFN-alpha-unrelated disease. Further studies are needed to establish whether the two types of GD differ not only from a clinical point of view but also because of different underlying pathogenetic mechanisms.  相似文献   
50.
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