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51.
PURPOSE: Interleukin-18 (IL-18) is an immunostimulatory cytokine with antitumor activity in preclinical models. A phase I study of recombinant human IL-18 (rhIL-18) was done to determine the toxicity, pharmacokinetics, and biological activities of rhIL-18 administered at different doses in two different schedules to patients with advanced cancer. EXPERIMENTAL DESIGN: Cohorts of three to four patients were given escalating doses of rhIL-18 as a 2-h i.v. infusion either on 5 consecutive days repeated every 28 days (group A) or once a week (group B) for up to 6 months. Toxicities were graded using standard criteria. Blood samples were obtained for safety, pharmacokinetic, and pharmacodynamic measurements. RESULTS: Nineteen patients (10 melanoma and 9 renal cell cancer) were given rhIL-18 in doses of 100, 500, or 1,000 microg/kg (group A) or 100, 1,000, or 2,000 microg/kg (group B). Common side effects included chills, fever, headache, fatigue, and nausea. Common laboratory abnormalities included transient, asymptomatic grade 1 to 3 lymphopenia, grade 1 to 4 hyperglycemia, grade 1 to 2 anemia, neutropenia, hypoalbuminemia, liver enzyme elevations, and serum creatinine elevations. No dose-limiting toxicities were observed. Biological effects of rhIL-18 included transient lymphopenia and increased expression of activation antigens on lymphocytes. Increases in serum concentrations of IFN-gamma, granulocyte macrophage colony-stimulating factor, and IL-18-binding protein were observed following dosing. CONCLUSIONS: rhIL-18 can be given in biologically active doses by either weekly infusions or daily infusions for 5 days repeated every 28 days to patients with advanced cancer. Toxicity was generally mild to moderate, and a maximum tolerated dose of rhIL-18 by either schedule was not determined.  相似文献   
52.
We have analyzed the predictive/prognostic value of Bcl‐2 protein in breast cancer patients treated with neoadjuvant chemotherapy. One hundred and ten patients were submitted to two different chemotherapeutic regimens: a) 5‐fluorouracil, adriamycin or epirubicin, and cyclophosphamide (FAC/FEC) during 2–6 cycles before surgery and 3 or 4 additional cycles of FAC/FEC after surgery (n=40) and b) doxorubicin (D) 75mg/m2 or epirubicin (E) 120mg/m2 during 4 cycles before surgery, and 6 cycles of cyclophosphamide, methotrexate, and 5‐fluorouracil (CMF) after surgery (n=70). Bcl‐2 expression, evaluated by immunohistochemistry, did not change significantly after chemotherapy and was not related to clinical/pathological response. In FAC/FEC group, Bcl‐2 positive expression after chemotherapy correlated with better disease free survival (DFS) and overall survival (OS) (P=0.008 and P=0.001). In D/E group, Bcl‐2 also correlated with better DFS and OS (P=0.03 and P=0.054) in the post‐chemotherapy biopsies. An unusual nuclear localization of Bax was observed in some biopsies, but this localization did not correlate with the tumor response or outcome of the patients. We found that a high Bcl‐2 expression had no predictive value but had prognostic value in breast cancer patients treated with neoadjuvant anthracycline based chemotherapy.  相似文献   
53.
Hemiretinal vein occlusion associated with membranous glomerulonephritis   总被引:1,自引:0,他引:1  
PURPOSE: To report a patient in whom the finding of hemiretinal vein occlusion led to the diagnosis of membranous glomerulonephritis. DESIGN: Interventional case report. METHODS: A 44-year-old tennis instructor presented with a 1-week history of blurred vision in the left eye. Examination of the left eye demonstrated a best-corrected visual acuity of 20/40 and an inferior hemiretinal vein occlusion. RESULTS: Blood pressure was normal, and the patient was referred for a medical examination, which revealed membranous glomerulonephritis. The patient was treated with oral prednisone and cyclosporine. Four months after presentation, the left eye demonstrated resolution of the vascular abnormalities and had a best-corrected visual acuity of 20/20. CONCLUSION: Retinal vein occlusion may be associated with membranous glomerulonephritis. Treatment of the systemic disease may be associated with regression of the retinal vascular abnormalities.  相似文献   
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PURPOSE: Three-dimensional conformal radiation therapy requires the precise definition of the target volume. Its potential benefits could be offset by the inconsistency in target definition by radiation oncologists. In a previous survey of radiation oncologists, a large degree of variation in target volume definition of cervical esophageal cancer was noted for the boost phase of radiotherapy. The present study evaluated whether special training could improve the consistency in target volume definitions. METHODS AND MATERIALS: A pre-training survey was performed to establish baseline values. This was followed by a special one-on-one training session on treatment planning based on the RTOG 94-05 protocol to 12 radiation oncologists. Target volumes were redrawn immediately and at 1-2 months later. Post-training vs. pre-training target volumes were compared. RESULTS: There was less variability in the longitudinal positions of the target volumes post-training compared to pre-training (p < 0.05 in 5 of 6 comparisons). One case had more variability due to the lack of a visible gross tumor on CT scans. Transverse contours of target volumes did not show any significant difference pre- or post-training. CONCLUSION: For cervical esophageal cancer, this study suggests that special training on protocol guidelines may improve consistency in target volume definition. Explicit protocol directions are required for situations where the gross tumor is not easily visible on CT scans. This may be particularly important for multicenter clinical trials, to reduce the occurrences of protocol violations.  相似文献   
56.
Neurobehavioral changes have been described in workers occupationally exposed to styrene vapors. Alterations of neurotransmitters and loss of neurons have been observed in brains of styrene-exposed rats. However, the mechanisms of neuronal damage are not yet clearly understood. We have characterized the cellular alterations induced by the main reactive intermediate of styrene metabolism, styrene 7,8-oxide (SO) in the human neuroblastoma SK-N-MC cell line and primary culture of rat cerebellar granule cells (CGC). SK-N-MC cells exposed to SO (0.3-1 mM) displayed apoptotic morphology, together with chromatin condensation and DNA cleavage into high molecular weight fragments of regular size. These features were accompanied by the activation of class II caspases, as detected with the DEVD assay, by following the cleavage of the caspase-substrate poly (ADP-ribose) polymerase (PARP) and by detection of the active fragment of caspase-3. Pre-incubation of the cells with the caspase inhibitor z-VAD-fmk reduced the cellular damage induced by SO, suggesting that caspases play an important role in SO toxicity. Increased proteolysis by class II caspases was detected also in primary culture of CGC exposed to SO. In addition, the presence of the 150-kDa cleavage product of alpha-fodrin suggests a possible activation of calpains in SK-N-MC cells. Moreover, SO did not affect the level of expression of the p53 protein, even though it is known to cause DNA damage. The identified intracellular pathways affected by SO exposure provides end-points that can be used in future studies for the evaluation of the neurotoxic effect of styrene in vivo.  相似文献   
57.
BACKGROUND: It was demonstrated previously that cerebellar adenosine modulates ethanol-induced motor incoordination via A(1) subtype of adenosine receptors. Several reports suggest the involvement of brain glutamate mechanisms, in particular N-methyl-d-aspartate (NMDA) receptor sites, in the central nervous system (CNS) actions of ethanol. Mutually antagonistic functional responses as a result of glutamate and adenosine within the brain regions have also been well documented. METHODS: With the use of rotorod performance as the test response, this study was conducted to evaluate possible functional interactions between cerebellar adenosine and glutamate and its consequence on ethanol-induced motor incoordination. Except for ethanol, which was injected intraperitoneally, all drugs used were microinfused directly into the cerebellum. RESULTS: Direct intracerebellar microinfusion of glutamate (125, 250, and 500 ng) and the antagonist l-glutamic acid diethyl-ester (125, 250, and 500 ng) markedly and dose-dependently attenuated and accentuated, respectively, ethanol-induced motor incoordination, suggesting an involvement of glutamate. Subsequently, intracerebellar microinfusions of NMDA (125, 250, and 500 ng) and its antagonists AP-5 [(+)-2-amino-5-phosphoropentanoic acid; 125, 250, and 500 ng] and (+)-MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclo-hepten-5,10-imine hydrogen maleate; 25, 50, and 100 ng] significantly attenuated and accentuated, respectively, ethanol-induced motor incoordination in a dose-related manner, indicating participation of NMDA receptor. The attenuation of ethanol-induced motor incoordination by glutamate and NMDA was receptor mediated as it was antagonized by their receptor antagonists. Adenosine A(1) -selective agonist N(6) -cyclohexyladenosine and antagonist 8-cyclopentyl-1,3-dipropylxanthine functionally opposed the attenuation by glutamate and NMDA and the accentuation by L-glutamic acid diethyl-ester, AP-5, and (+)-MK-801, respectively, of ethanol-induced motor incoordination. CONCLUSIONS: These results suggest a functional antagonism between glutamate NMDA and adenosine A(1) receptors exhibiting a co-modulation of ethanol-induced motor incoordination within the cerebellum.  相似文献   
58.
BACKGROUND: Neurologic impairment after coronary artery bypass grafting is associated with cerebral embolization. An important cause of embolism is aortic manipulation. Constructing both distal and proximal anastomoses during a single period of aortic cross-clamping avoids this source of embolism and may reduce neurologic injury after coronary artery bypass grafting. METHODS: Fifty consecutive patients undergoing coronary artery bypass grafting were prospectively randomized to group 1, in which a single aortic cross-clamping was used to construct distal and proximal anastomoses, or to group 2, in which the proximal anastomoses were each constructed with a partial occluding aortic clamp. Levels of S-100 and troponin-T release were measured preoperatively and postoperatively. RESULTS: Aortic cross-clamp time was significantly longer in group 1, but other preoperative and intraoperative variables were equally represented in both groups. Control group levels of S-100 and troponin-T were similar. Postoperative S-100 levels were significantly higher in group 2 than in group 1 (p < 0.015). No significant difference was found between the groups in postoperative troponin-T levels. CONCLUSIONS: The results of this trial suggest improved cerebral protection is associated with the single aortic cross-clamp technique for coronary artery bypass grafting with no increase in myocardial damage. The single aortic cross-clamp technique is simple and inexpensive. We recommend its wider use.  相似文献   
59.
Background: A 7-valent pneumococcal conjugate vaccine (7vPnC) has markedly reduced invasive pneumococcal disease (IPD) in routine use in the USA and is in clinical development in Japan. But a 13-valent pneumococcal conjugate vaccine (13vPnC) would cover even more serotypes. Because vaccines are administered to children by s.c. injection in Japan but by i.m. injection in the USA, a phase I study of s.c. injected 13vPnC in healthy Japanese adults was appropriate before commencing trials in Japanese children and older adults.
Methods: This was a randomized comparison in healthy Japanese adults of s.c. administered 13-valent pneumococcal conjugate vaccine and s.c. administered 23-valent plain polysaccharide pneumococcal vaccine (23vPn). Local and systemic reactions were recorded in a daily diary for 14 days after injection. IgG antibodies to serotype-specific capsular polysaccharide were measured on enzyme-linked immunosorbent assay on samples taken before and approximately 1 month after immunization.
Results: A total of 15 subjects were evaluable for safety review in each treatment group. There was a trend towards more local reactions in the 13vPnC group, which may be associated with s.c. administration of aluminum-containing vaccines as used routinely in Japan; but the local reactogenicity was mostly mild or moderate. Both 13vPnC and 23vPn were immunogenic for all types, with the exception of 6A, which is not included in 23vPn and for which only 13vPnC was immunogenic.
Conclusions: Overall, immunogenicity and tolerance was adequate to lead to studies of 13vPnC in both infants and older adults in Japan, using the s.c. route if appropriate.  相似文献   
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