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41.
The aim of the review is to describe the different techniques and materials available to reconstruct the tarsoconjunctival layer of the eyelid; to analyze their indications, advantages, and disadvantages.

We searched the Cochrane, PubMed, and Ovid MEDLINE databases for English articles published between January 1990 and January 2017 using variations of the following key words: “posterior lamella,” “eyelid reconstruction,” “tarsoconjunctival,” “flap,” and “graft.” Two reviewers checked the abstracts of the articles found to eliminate redundant or not relevant articles. The references of the identified articles were screened manually to include relevant works not found through the initial search.

The search identified 174 articles. Only a few articles with a therapeutic level of evidence were found. Techniques for the posterior lamellar reconstruction can be categorized as local, regional, and distant flaps; tarsoconjunctival, heterotopic, homologous, and heterologous grafts. Several techniques and variations on the techniques exist to reconstruct the posterior lamella, and, for similar indications, there’s no evidence of the primacy of one over the other. Defect size and location as well as patient features must guide the oculoplastic surgeon’s choice. The use of biomaterials can avoid possible complications of the donor site.  相似文献   

42.
Aims: Nestin (a neuronal stem cell/progenitor cell marker of central nervous system development), vimentin (which is ubiquitously expressed in mesenchymal cells), and the glucocorticoid receptor (GR, which is involved in the immune response, cell proliferation, and apoptosis) have been shown to interact in embryonic and undifferentiated tissues in modulating cell proliferation. The aim of this study was to analyse nestin, vimentin and GR expression in tumour tissue (melanoma), and their association with clinicopathological variables, to evaluate any effect on tumour progression. Methods and results: Immunohistochemistry, double‐label immunofluorescence and confocal laser scanning microscopy were performed on biopsy specimens of cutaneous melanoma from 81 patients. Fisher’s and Pearson’s tests showed a correlation between nestin, vimentin and subcellular GR location (P = 0.008). Their concomitant expression also correlated with Clark level and thickness (P = 0.02 and P = 0.029, respectively). Kaplan–Meier analysis revealed a poorer outcome for stage III and IV patients with associated expression of nestin, vimentin and cytoplasmic GR in tumour tissue (P = 0.02). Conclusions: These results suggest the presence in melanoma of growth mechanisms involving nestin, vimentin, and GR, similarly to that occurring in embryonic and undifferentiated cells, and may help in understanding tumour biology to provide a molecular basis for clinical therapies.  相似文献   
43.
Lu  YQ; Nichols  ME; Bigbee  WL; Nagel  RL; Blumenfeld  OO 《Blood》1987,69(2):618-624
We have explored the polymorphism of the glycophorin system in the human erythrocyte membrane using the immunoblotting techniques and examining 52 individuals selected without prior bias as to their serologic state and ten documented serologic variants of M, N, S, s blood group system. Polyclonal antisera to alpha glycophorin and to alpha glycophorin CNBr carboxyl terminal fragment C (residues 82-131) and M and N specific monoclonal antibodies (MoAbs) were used. The first two reagents detect specific regions of the alpha glycophorin molecule and all electrophoretically resolved species of glycophorins immunologically related to alpha and delta glycophorins (delta glycophorin, [alpha-delta] hybrids and other glycophorins with an alteration in the carboxyl terminal segment); the M and N MoAbs identified the glycophorin species containing or lacking the M or N determinant in the amino terminal octapeptide structures. We find that immunoblotting confirmed in all cases the serologically determined phenotype; we also find that polymorphic forms of the glycophorin system are relatively infrequent; immunoblotting, independent from serologic testing, was capable of detecting five mutants, two most likely S-s-U-phenotypes; a new glycophorin species was detected in normal red cells with both antiglycophorin and antipeptide C sera, which is not evident with MoAbs; immunoblots of known glycophorin variants (En(a-), U-, Mg, Mi I, II, III, V, and Sta) confirmed but also extended our knowledge of the abnormal glycophorins involved; and the He+ and Wrb(-) cells showed normal patterns.  相似文献   
44.
Cytogenetic and histologic correlations in malignant lymphoma   总被引:9,自引:0,他引:9  
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change.  相似文献   
45.
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
46.
Rick  ME; Krizek  DM 《Blood》1986,67(6):1649-1654
Factor VIII coagulant protein (VIII:C) functions as a critical cofactor with factor IXa, calcium ions, and phospholipid during the activation of factor X. In the course of this reaction, the activity of VIII:C is first increased and then is destroyed by one or more serine proteases that are part of the coagulation sequence. In this study, we have investigated the influence of platelets on the inactivation of VIII:C by plasmin. Platelets were separated from plasma proteins in the presence of granule release inhibitors and were incubated with plasmin and isolated VIII:C or the complex of purified VIII:C/von Willebrand factor (vWF); VIII:C activity and antigen levels were assessed over time. In the presence of platelets, the isolated VIII:C showed an initial increase in VIII:C activity that was not present when platelets were absent, and the VIII:C/vWF showed an increase in VIII:C activity over that seen when platelets were absent. In addition, platelets stabilized VIII:C activity over a one-hour time course when compared with buffer. The VIII:C antigen did not increase and decreased slowly whether platelets were present or absent. Preincubating the platelets with ristocetin, collagen, or plasmin did not alter the results, and experiments using platelets from a patient with severe von Willebrand's disease also showed a pattern similar to that seen with normal platelets. Experiments using fixed platelets or phospholipid vesicles showed that they did not support the activation reaction or delay the inactivation reaction. These studies demonstrate that platelets modulate the activation and inactivation of VIII:C by plasmin, apparently by a mechanism that is independent of the platelet release reaction.  相似文献   
47.
Metabolic Brain Disease - Aicardi-Goutières Syndrome (AGS) is a monogenic leukodystrophy with pediatric onset, clinically characterized by a variable degree of neurologic impairment. It...  相似文献   
48.
The aim of this study was to evaluate the distribution and clinical significance of hepatitis C virus (HCV) genotypes in European patients with compensated cirrhosis due to hepatitis C (Child class A) seen at tertiary referral centres. HCV genotypes were determined by genotype-specific primer PCR in 255 stored serum samples obtained from cirrhotics followed for a median period of 7 years. Inclusion criteria were biopsy-proven cirrhosis, absence of complications of cirrhosis and exclusion of all other potential causes of chronic liver disease. The proportion of patients with types 1b, 2, 3a, 1a, 4 and 5 were 69%, 19%, 6%, 5%, 0.5% and 0.5%, respectively. Kaplan–Meier 5-year risk of hepatocellular carcinoma (HCC) was 6% and 4% for patients infected by type 1b and non-1b, respectively ( P =0.8); the corresponding figures for decompensation were 18% and 7% ( P =0.0009) and for event-free survival were 79% and 89% ( P =0.09), respectively. After adjustment for baseline clinical and serological features, HCV type 1b did not increase the risk for HCC [adjusted relative risk=1.0 (95% confidence interval=0.47–2.34)], whereas it increased the risk for decompensation by a factor of 3 (1.2–7.4) and decreased event-free survival by a factor of 1.7 (0.9–3.10). In conclusion, type 1b and, to a lesser extent, type 2, are the most common HCV genotypes in European patients with cirrhosis. HCV type 1b is not associated with a greater risk for HCC, but increases the risk for decompensation by threefold in patients with cirrhosis.  相似文献   
49.
A drastic reduction in homologous blood or plasma transfusion becomes necessary to prevent the risks of severe infections disease transmission. The authors studied the possibility of homologous blood save in cardiac surgery by peroperative autotransfusion. This procedure, although it diminished the average blood bank requirements, above all for an unexplained decrease in postoperative bleeding, did not obtain the good results that other authors had with the technique of 2 or 3 preoperative withdrawal, storage and postoperative reinfusion. In future our trend is to associate preoperative and intraoperative withdrawals to take advantage of both techniques.  相似文献   
50.
A multicentre study involving 9 Italian institutions was carried out to compare the efficacy and safety of ranitidine 150 mg b.i.d. and ranitidine 300 mg nocte in the treatment of reflux oesophagitis. 117 patients with histologically proven oesophagitis were randomly allocated to two comparable treatment groups. Efficacy and reliability were evaluated by clinical and laboratory tests at the beginning of the study, and at 3 and 6 weeks; endoscopy and biopsies were performed at the beginning and at 6 weeks. Treatment with ranitidine for 6 weeks led to total disappearance of gastro-oesophageal reflux symptoms in 60% of patients, with percentages of partial improvement varying between 85% and 95% of cases. Improvement in the results of endoscopic examination was 85%, of which 55% were cured. Microscopic examination revealed an improvement of 36% and 44%, with a cure rate of 18% and 26% respectively. With regard neither to the regression of symptoms nor to the macroscopic and microscopic inflammation of the oesophageal mucosa did statistical examination show significant differences in the therapeutic efficacy of ranitidine 150 mg b.i.d. or 300 mg nocte for treatment of reflux oesophagitis.  相似文献   
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