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One limiting factor for automated two-red blood cells collections (2-RBC) is its potential iron depletion. We analyzed hematological parameters and iron balance before, two and four months after 2-RBC of 96 non-supplemented male donors. Four months after 2-RBC, ferritin level was significantly lower (P < 0.01) than baseline levels and the number of donors who presented ferritin <30 ng/ml increased from 18 to 47. We concluded that four months was not sufficient for iron recuperation in the population studied. In an attempt to avoid iron depletion after 2-RBC, we recommend augmentation in the interval between blood donations and pre-donation ferritin measurement.  相似文献   
104.

Background  

We previously reported risk haplotypes for two genes related with serotonin and dopamine metabolism: MAOA in migraine without aura and DDC in migraine with aura. Herein we investigate the contribution to migraine susceptibility of eight additional genes involved in dopamine neurotransmission.  相似文献   
105.
PURPOSE: The aim of this study was to define the risk of second cancer in nongastric marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT). EXPERIMENTAL DESIGN: We considered for the analysis 157 patients with a confirmed histology of marginal zone B-cell lymphoma of MALT, presenting with a clinically prevalent extranodal site of disease, except for stomach. All patients came from two hematologic institutions of Northern Italy. We compared the occurrence of second cancer with respect to the general population by calculating the standardized incidence ratio, with the age- and sex-specific incidence rates of a cancer registry of Northern Italy (Lombardia) as a reference. RESULTS: A history of solid neoplasia was present in 29 (18%) patients for a total number of 30 neoplasms: 25 solid tumors, 2 hematologic diseases (1 Hodgkin's lymphoma and 1 essential thrombocythemia), and 3 nonmelanoma in situ skin cancers. In 4 patients, the site of cancer and lymphoma was the same. In 21 cases the solid tumor preceded the MALToma, in 3 the neoplasm was concomitant, whereas in 6 it was subsequent. For the entire group, the standardized incidence ratio of an additional malignancy was 0.8 [95% confidence interval (95% CI), 0.55-1.17; P = 0.2]. After excluding nonmelanoma skin cancer, the standardized incidence ratio of a second tumor was 0.75 (95% CI, 0.5-1.12; P = 0.2). After excluding all previous malignancies, the standardized incidence ratio of a second cancer was 1.32 (95% CI, 0.69-2.55; P = 0.4). The comparison of risks between males and females was not significant in each group analysis. CONCLUSIONS: Patients with nongastric MALT lymphomas are not at increased risk for other neoplasms compared with the general population of the same geographic area.  相似文献   
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PURPOSE: pRb2/p130, a member of the Retinoblastoma gene family, has been shown to be a powerful prognostic factor in several malignancies. We sought to evaluate pRb2/p130 protein expression and its clinical effect in patients affected with soft tissue sarcomas (STS). EXPERIMENTAL DESIGN: Expression of pRb2/p130 was evaluated by immunohistochemistry on formalin-fixed, paraffin-embedded sections in 41 STSs. Results obtained were correlated with clinicopathologic variables and disease-free and overall survival (OS) in univariate and multivariate analysis. RESULTS: Expression of pRb2/p130 was diminished in 25 (61%) tumors, whereas the remaining ones (39%) were classified as high expressors. No correlation between pRb2/p130 expression and clinicopathologic variables was observed. However, a direct relationship between pRb2/p130 expression and clinical outcome of the patients was found in the subgroup of nonmetastatic tumors (n = 31). In univariate analysis, reduced pRb2/p130 expression was a negative prognostic factor and correlated with shorter disease-free survival (P = 0.021) and OS (P = 0.017) survival. In multivariate analysis, reduced pRb2/p130 expression was confirmed to be an independent predictor of shorter OS when considered together with tumor stage and grading (risk ratio, 7.893; confidence interval, 1.618-38.509; P = 0.011). CONCLUSIONS: This study shows for the first time the potential prognostic value of pRb2/130 expression evaluated on formalin-fixed, paraffin-embedded sections in STSs patients. pRb2/p130 immunoreactivity can be used to predict OS in patients with nonmetastatic STSs and, therefore, may represent a new prognostic marker.  相似文献   
108.
Immunohistochemical and/or indirect immunofluorescence analysis with monoclonal antibody (MAb) H19 demonstrated the expression of protectin (CD59) in 54 surgically removed metastatic melanoma lesions and on 8 out of 12 melanoma cell lines. CD59 expression had a low degree of intra- and intertumor heterogeneity. SDS-PAGE analysis showed that the molecular weight of CD59 expressed on melanoma cells is about 20 kDa. Treatment of melanoma cells with 5 U/ml of phosphatidylinositol-specific phospholipase C completely abolished cell-surface expression of CD59. Interferon-γ and/or tumor necrosis factor-α or phorbol 12-myristate 13-acetate neither modulated the expression of CD59 by melanoma cells nor influenced the amounts of CD59-specific mRNA. F(ab')2 fragments of anti-CD59 MAb YTH53.1 did not inhibit the lysis of melanoma cells by allogeneic natural killer (NK) cells or lymphokine-activated killer (LAK) cells. In contrast, the whole lg molecule of MAb H19 or YTH53. I significantly (p < 0.05) enhanced NK-cell-mediated lysis of melanoma cells, suggesting the induction of antibody-dependent cell-mediated cytotoxicity. Lastly, masking of CD59 by MAb YTH53. I or its F(ab')2 fragments significantly (p < 0.05) enhanced, in a dose-dependent fashion, the lysis of anti-GD3-sensitized melanoma cells by homologous complement. These data demonstrate that CD59 expressed by human melanoma cells might regulate host-tumor interaction by protecting neoplastic cells from complement-mediated lysis. © 1995 Wiley-Liss, Inc.  相似文献   
109.
The blood-brain barrier (BBB) is a gate that controls the influx and efflux of a wide variety of substances and consequently restricts the delivery of drugs into the central nervous system (CNS). Brain tumours may disrupt the function of this barrier locally and nonhomogeneously. Therefore, the delivery of drugs to brain tumours has long been a controversial subject. The current concept is that inadequate drug delivery is a major factor that explains the unsatisfactory response of chemosensitive brain tumours. Various strategies have been devised to circumvent the BBB in order to increase drug delivery to the CNS. The various approaches can be categorised as those that attempt to increase delivery of intravascularly administered drugs, and those that attempt to increase delivery by local drug administration. Strategies that increase delivery of intravascularly injected drugs can manipulate either the drugs or the capillary permeability of the various barriers (BBB or blood-tumour barrier), or may attempt to increase plasma concentration or the fraction of the drug reaching the tumour (high-dose chemotherapy, intra-arterial injection). Neurotoxicity is a major concern with increased penetration of drugs into the CNS or when local delivery is practised. Systemic toxicity remains the limiting factor for most methods that use intravascular delivery. This review evaluates the strategies used to increase drug delivery in view of current knowledge of drug pharmacokinetics and its relevance to clinical studies of chemosensitive brain tumours. The main focus is on primary CNS lymphoma, as it is a chemosensitive brain tumour and its management routinely utilises specialised strategies to enhance drug delivery to the affected CNS compartments.  相似文献   
110.
Capillary GC/MS analysis based on polar and non-polar columns has been applied to evaluation of the volatile oils hydrodistilled from thyme (Thymus vulgaris L.) plants. The adopted methodology has been used to monitor seasonal variations in the composition of the oil obtained from thyme herbs harvested at different periods during the plant vegetative and life cycles. Oils from thyme plants of young (2 years) and old (5 years) cultivations have been evaluated from four and two collections, respectively, effected throughout May/December growth period. Generally, the oil was found to be rich in the active monoterpene phenols (thymol and carvacrol) and their corresponding monoterpene hydrocarbon (HC) precursors (p-cymene and gamma-terpinene), which collectively showed synchronized patterns of variation during the different collection periods and in different seasons. The oil from old plant collected in May/June period (0.15% v/w) was characterized by significantly lower levels of monoterpene HCs (mainly gamma-terpinene) and the highest levels of the oxygenated monoterpenes (linalool and borneol), monoterpene phenols (mainly thymol) and their derivatives (mainly carvacrol methyl ether), sesquiterpenes (mainly beta-caryophyllene) and their oxygenated derivatives (e.g. caryophyllene oxide) in comparison with all other samples. A characteristic presence of camphor and thymodihydroquinone was also observed in the old plant oils. On the other hand, the young plant, collected in June/July just before the end of the vegetative cycle, provided the best oil yield (1.2%) with also the highest % content of the monoterpene phenols (thymol: 51.2% and carvacrol: 4%). This latter growth period can represent the best harvest time of young thyme plants in order to obtain an essential oil with better quality and quantity.  相似文献   
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