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41.
Elevated levels of matrix metalloproteinase-9 (MMP-9) associates with predictors of multiple sclerosis (MS) activity. We analysed serum levels and mRNA expression of MMP-9 and its inhibitor TIMP-1 in peripheral mononuclear cells of 14 MS patients after autologous hematopoietic stem cell transplantation (AHSCT). All but 2 patients stabilized after AHSCT. A significant decrease of MMP-9 levels was seen up to 36 months after AHSCT. TIMP-1 levels did not change. MMP-9 mRNA levels correlated with the CD4+ T cell count (p<0.0001). The significant and persistent change in MMP-9 activity after AHSCT may be caused in part by the effect of AHSCT in the CD4+ T cell count. 相似文献
42.
Angulo E Casadó V Mallol J Canela EI Viñals F Ferrer I Lluis C Franco R 《Brain pathology (Zurich, Switzerland)》2003,13(4):440-451
Immunostaining of adenosine receptors in the hippocampus and cerebral cortex from necropsies of Alzheimer disease (AD) patients shows that there is a change in the pattern of expression and a redistribution of receptors in these brain areas when compared with samples from controls. Adenosine A1 receptor (A1R) immunoreactivity was found in degenerating neurons with neurofibrillary tangles and in dystrophic neurites of senile plaques. A high degree of colocalization for A1R and betaA4 amyloid in senile plaques and for A1R and tau in neurons with tau deposition, but without tangles, was seen. Additionally, adenosine A2A receptors, located mainly in striatal neurons in controls, appeared in glial cells in the hippocampus and cerebral cortex of patients. On comparing similar samples from controls and patients, no significant change was evident for metabotropic glutamate receptors. In the human neuroblastoma SH-SY5Y cell line, agonists for A1R led to a dose-dependent increase in the production of soluble forms of amyloid precursor protein in a process mediated by PKC. A1R agonist induced p21 Ras activation and ERK1/2 phosphorylation. Furthermore, activation of A1R led to and ERK-dependent increase of tau phosphorylation and translocation towards the cytoskeleton. These results indicate that adenosine receptors are potential targets for AD. 相似文献
43.
BRAF mutations characterize colon but not gastric cancer with mismatch repair deficiency 总被引:8,自引:0,他引:8
Oliveira C Pinto M Duval A Brennetot C Domingo E Espín E Armengol M Yamamoto H Hamelin R Seruca R Schwartz S 《Oncogene》2003,22(57):9192-9196
Genes from the RAF family are Ras-regulated kinases involved in growth cellular responses. Recently, a V599E hotspot mutation within the BRAF gene was reported in a high percentage of colorectal tumors and significantly associated to defective mismatch repair (MMR). Additionally, BRAF mutations were described only in K-Ras-negative colon carcinomas, suggesting that BRAF/K-Ras activating mutations might be alternative genetic events in colon cancer. We have addressed to what extent the tumorigenic-positive selection exerted by BRAF mutations seen in colorectal MMR-deficient tumors was also involved in the tumorigenesis of gastric cancer. Accordingly, BRAF mutations were detected in 34% (25/74) of colorectal MMR-deficient tumors and in 5% (7/142) of MMR-proficient colorectal cases (P=0.0001). All mutations found in the MSI cases corresponded to the previously reported hotspot V599E. Two D593K and a K600E additional mutations were also detected in three MSS cases. However, only one mutation of BRAF was found within 124 MSS gastric tumors and none in 37 MSI gastric tumors, clearly suggesting that BRAF mutations are not involved in gastric tumorigenesis. Nonetheless, a high incidence of mutations of K-Ras was found within the MSI gastric group of tumors (P=0.0005), suggesting that the activation of K-Ras-dependent pathways contributes to the tumorigenesis of gastric cancers with MMR deficiency. Accordingly, our results show evidences that BRAF mutations characterize colon but not gastric tumors with MMR deficiency and are not involved in the tumorigenesis of gastric cancer of the mutator phenotype pathway. 相似文献
44.
Rebull Fatsini J Reverté Simó M Piñas Forcadell I Ortí Llavería A González Gavilán L Contreras Barbeta E 《Revista espa?ola de salud pública》2003,77(3):373-382
BACKGROUND: Human immuno-deficiency virus (HIV) infection is one of the leading public health problems in our country. Preventive education has shown itself to be a useful tool for curtailing this disease. The objective of this study is that of assessing the effectiveness of a preventive intervention at the Secondary Schools in the Baix Ebre and Montsià areas of the Tortosa Healthcare District aimed at reducing the risk of HIV transmission and furthering the knowledge of this disease. METHOD: A pre/post intervention study was conducted with no control group. A total of 19 schools, corresponding to the fourth year of Compulsory Secondary Education and first year of "Bachillerato" studies were invited to participate. The activity consisted of a workshop 60-90 minutes in length, in conjunction with educational material. A questionnaire was used as the gauging tool. RESULTS: Twelve schools agreed to participate, a total of 896 answers having been gotten for the pre-test and 805 answers for the post-test. A statistically significant increase was found for 52% (10/19) of the items regarding the correct answers on the post-test. A statistically significant improvements was found in four of the five items (80%) related to attitudes, and in five of the eight (62.5%) items related to overall knowledge of this infection following the intervention. A statistically significant improvement regarding prevention-related knowledge was found solely in one of the six items (16.6%). CONCLUSIONS: Preventive activities in the form of participational workshops are a good way of furthering the knowledge and improving the attitudes regarding HIV/AIDS of the participating teenagers. As no curative treatment exists for this disease, prevention from the educational realm is of importance for curtailing increased HIV transmission. 相似文献
45.
46.
Sastre-Garriga J Reverter JC Font J Tintoré M Espinosa G Montalban X 《Annals of neurology》2001,49(3):408-411
Recent works claiming that primary antiphospholipid syndrome (PAPS) cannot be clinically distinguished from multiple sclerosis (MS) recommend that MS patients be screened for anticardiolipin antibodies (ACA). In this study 296 randomly selected patients with MS and clinically isolated syndromes and 51 healthy controls were analyzed; ACA, anti-beta2-glycoprotein I, or antiprothrombin was found in 6 patients. No predominance of any kind of clinical manifestations and no cardinal manifestations of PAPS were found in these patients. ACA tests should be performed only when a suspicion of PAPS is raised and atypical clinical presentation for MS is found. 相似文献
47.
48.
Fifteen patients with Hodgkin's disease resistant to the chemotherapy combinations of cyclophosphamide, vinblastine, procarbazine and prednisone and doxorubicin, bleomycin, vinblastine, and dacarbazine were treated with lomustine, etoposide, and prednimustine. Four of them achieved complete remission and two achieved partial remission (overall response rate, 40%). The median duration of response was 5.5 months, with two complete responders relapsing at 4 and 17 months and the other two remaining disease-free at 7 and 18 months, whereas disease progression was observed at 2.5 and 6 months in the partial responders. Extrahematological toxicity was scarce. Severe myelosuppression was observed in only three patients. These results indicate that lomustine, etoposide, and prednimustine can play a role in the treatment of advanced resistant Hodgkin's disease. 相似文献
49.
Interaction between interleukin-6 and the natural anticoagulant system in acute stroke. 总被引:19,自引:0,他引:19
N Vila J C Reverter J Yagüe A Chamorro 《Journal of interferon & cytokine research》2000,20(3):325-329
Inflammatory reactions mediated by cytokines are involved in the pathogenesis of acute stroke. Decrease in circulating levels of protein C (PC) and protein S (PS) induced by inflammatory cytokines has been postulated as a potential mechanism for a procoagulant tendency during acute stroke. The procoagulant state associated with impairments in natural anticoagulants may induce microvascular obstruction leading to a tissue perfusion reduction that worsens cerebral ischemia. Interleukin-6 (IL-6) regulate the synthesis of C4b-binding protein (C4BP), an acute-phase protein that also regulates PS plasma levels. We measured IL-6, C4BP, erythrocyte sedimentation rate (ESR), total and free PS and PC in 44 patients with acute ischemic stroke to determine if IL-6 decreases circulating levels of natural anticoagulants through the C4BP pathway and if these acute changes in natural anticoagulants may have clinical implications. Patients with higher levels of IL-6 had more severe neurologic deficits on admission, greater infarct size, higher levels of acute-phase reactants, and lower levels of free PS. IL-6 was significantly correlated with C4BP, ESR, and free PS levels. PC levels were also lower in the group of patients with greater IL-6, but differences were not statistically significant. No correlations were found between C4BP and natural anticoagulants. Severe neurologic deficit, greater infarct volume, atrial fibrillation, increased levels of inflammatory parameters (ESR and IL-6), and reduced levels of free PS were associated with disabling stroke at 3 months, but only neurologic severity and ESR remained as independent predictors of stroke disability on multiple regression analysis. Inflammatory reactions mediated by IL-6 during the acute phase of stroke influence the modulation of free PS. However, variations in free PS levels do not have implications for clinical outcome in stroke patients. The link between proinflammatory cytokines and free PS in the acute phase of stroke is not related to the C4BP pathway. 相似文献
50.
Joan Llobera Magdalena Esteva Enric Benito Josefa Terrasa Juli Rifà Onofre Pons Ascensión Maya 《Supportive care in cancer》2003,11(5):294-303
AIM: The evolution of performance status, disability, and quality of life (QL) according to the Hebrew Rehabilitation Center for Aged QL (HRCA-QL) index for cancer patients through their terminal period is described. The assessment of HRCA-QL validity and reliability is also described. DESIGN: A total of 200 cancer patients were followed up from the onset of their "terminal phase" until they died. Information on symptoms, performance, disability and QL were collected by patient's oncologists in hospital and by their family practitioners and community nurses when the patient was at home. Health measures were: the HRCA-QL index, Karnofsky performance status (KPS) and the Independence in Activities of Daily Living (IADL) index. RESULTS: The three indices were acceptable for a fair number of patients at the start of the terminal phase. Almost two-thirds had a KPS > or =60. With respect to the IADL index, the patients were independent in five of the six functions, with 80% having a HRCA-QL equal to or greater than 4. The median duration of the terminal period was 59 days. All three indices declined progressively, with marked deterioration in the last 2 weeks. The HRCA-QL index was highly correlated with KPS and the IADL index, had good internal consistency and showed an acceptable test-retest and inter-rater reliability. The HRCA-QL index was reactive to clinical changes. CONCLUSIONS: All three scales confirmed that terminal patients experience a progressive loss of performance, increase in dependence and deterioration of QL as they approach the end of life. Based in these results, we consider the HTCA-QL index valid for use in terminal cancer patients. 相似文献