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101.
102.
BACKGROUND AND AIMS: We previously reported that the sole clinicopathological parameters of carcinomas diagnosed in a single institution in 1975 differed from those in patients diagnosed in 1995. The findings might be compatible with the loss of importance of the microsatellite instability of the carcinogenic pathway. MATERIALS AND METHODS: We examined the microsatellite status and selected immunomarkers (Ki-67, p53, BAX) in the archival material from 1975 (n=76) and 1995 (n=105). RESULTS AND CONCLUSION: The distribution of tumors showing no microsatellite instability, low microsatellite instability, and high microsatellite instability in the 2-yearly cohorts was similar (1975: 55.6%, 22.2%, 22.2%; 1995: 60.2%, 20.4%, 19.4%, respectively). The percentage of carcinomas showing microsatellite instability at the APC locus differed significantly (1975: 37.5%; 1995: 21.4%). The typical clinicopathological parameters of carcinomas exhibiting high microsatellite instability were largely shared by the carcinomas demonstrating instability at the APC locus. The carcinomas resected in 1995 more frequently demonstrated high expression of an antiapoptotic protein BAX and a different distribution of their Ki-67 proliferation fraction. The evolution of colorectal carcinoma in Poland also involves qualitative changes, including its genetic background.  相似文献   
103.
A comparative study was carried out of emissions from the catalytic combustion of pellets made from furniture board waste and pellets made from wood mixed with Fe2O3. The mass content of the Fe2O3 catalyst in the fuel was varied from 0% to 5%, 10%, and 15% in relation to the total dry mass weight of the pellets. The average flame temperature in the boiler was between 730 and 800 °C. The effect of the catalyst concentration in the fuel was analysed with respect to the contents of O2, CO2, CO, H2, and NOx in the flue gas and the combustion quality of the pellets in the heating boiler. Changes in the CO2 content and the proportion of unburned combustible components in the combustion residue were assessed. It was established that an increase in the Fe2O3 content of the prepared fuels had a positive effect on reducing NOx, CO, and H2 emissions. However, the proportion of iron oxide in the tested fuel pellets did not significantly influence changes in their combustion quality. A strong effect of the addition of Fe2O3 on the reduction of the average NOx content in the flue gas occurred with the combustion of furniture board fuel, from 51.4 ppm at 0% Fe2O3 to 7.7 ppm for an additive content of 15%. Based on the analysis of the residue in the boiler ash pan, the amount of unburned combustibles relative to their input amounts was found to be 0.09–0.22% for wood pellets and 0.50–0.31% for furniture board waste pellets.  相似文献   
104.
Patients (n = 127) with aneurysmal subarachnoid hemorrhage (SAH) were examined by transcranial Doppler ultrasonography (TCD) in a prospective study to follow the time course of the posthemorrhagic blood flow velocity in both the middle cerebral artery (MCA) and in the anterior cerebral artery (ACA). Results were analysed to reveal their relationship and predictive use with respect to the occurrence of delayed ischemic deficits. Mean flow velocities (MFV) higher than 120 cm sec(-1) in MCA and 90 cm sec(-1) in ACA were interpreted as indicative for significant vasospasm. In 20 of our 127 patients (16%) a delayed ischemic deficit (DID) was subsequently diagnosed clinically (DID+ group). Patients in the DID+ group can be characterized as those individuals who presented early during the observation period post-SAH with highest values of MFV, a faster increase and longer persistence of pathologically elevated MFV-values (exceeding 120 cm sec(-1) in MCA and 90 cm sec(-1) in ACA). They also show a greater difference in MFV-values if one compares the operated to the nonoperated side. Differences in MFV-values obtained in MCA or ACA were statistically significant (p < 0.05) for DID+ and DID- patients. The daily maximal increase of MFV was found between days 9 and 11 after SAH. In the DID+ group, the maximal MFV was 181 +/- 26 cm sec(-1) in MCA and 119 +/- 14 cm sec(-1) in ACA. In contrast to this, patients in the DID- group were found to present with MFV of 138 +/- 11 cm sec(-1) in MCA and 100 +/- 7 cm sec(-1) in ACA respectively. Delayed ischemic deficits appeared three times more often in DID+ patients than in patients with MFV < 120 cm sec(-1), if they showed a MFV > 120 cm sec(-1) in MCA. If pathological values were obtained in ACA, this ratio increases to about four times, if DID + patients presented with MFV > 90 cm sec(-1) versus patients with MFV < 90 cm sec(-1). Daily monitoring of vasospasm using TCD examination is thus helpful to identify patients at high risk for delayed ischemic deficits. This should allow us to implement further preventive treatment regimens.  相似文献   
105.
Medical measures that bear no known danger for the adult brain may trigger active neuronal death in the developing brain. Pharmacological blockade of N-methyl-D-aspartate or activation of GABA(A) receptors, blockade of voltage-dependent sodium channels, and oxygen induce widespread apoptotic neurodegeneration during the period of rapid brain growth in rodents. Because such measures are often necessary in critically ill infants and toddlers, search for adjunctive neuroprotective strategies is warranted. We report that 17beta-estradiol ameliorates neurotoxicity of drugs that block N-methyl-D-aspartate receptors, activate GABA(A) receptors, or block voltage-gated sodium channels and reduces neurotoxicity of oxygen in the infant rat brain. This neuroprotective effect is reversed by tamoxifen and cannot be reproduced by 17alpha-estradiol. 17Beta-estradiol did not affect GABA(A) or N-methyl-D-aspartate currents in hippocampal neuronal cultures, indicating that direct modulation of neurotransmitter receptor/channel properties by this compound cannot explain neuroprotective effect. 17beta-Estradiol did, however, increase levels of phosphorylated extracellular signal-regulated kinase 1/2 and AKT, suggesting that activation of these prosurvival proteins may represent one mechanism for its neuroprotective action. 17Beta-estradiol and related compounds may be neuroprotective agents suitable for use in critically ill infants and toddlers. Its supplementation may particularly help to improve neurocognitive outcome in preterm infants who are prematurely deprived of maternal estrogen.  相似文献   
106.
107.
Elevated C-reactive protein (CRP) levels have been found in patients with several malignancies. The aim of the present study was to analyze the diagnostic and prognostic values of CRP levels measurement in esophageal cancer (EC) patients in relation to its different histological subtypes (squamous cell carcinoma-ESCC and adenocarcinoma-AC of esophagus) and compared them with classic tumor markers-carcinoembryonic antigen (CEA) and squamous cell cancer antigen (SCC-Ag). The diagnostic sensitivity, specificity, and the areas under receiver operating characteristic curves (AUC) for all the proteins tested were defined. Serum CRP levels were statistically higher in EC, ESCC, and AC patients compared to healthy subjects and significantly increased in EC and ESCC patients with the presence of lymph node and distant metastases. The percentage of elevated CRP results in all the analyzed subgroups (EC, ESCC, and AC) was higher than CEA and SCC-Ag, similarly as AUC for CRP in comparison to SCC-Ag. Serum CRP level was a significant predictor of EC and ESCC patients' survival in univariate analysis. In conclusion, these results indicate that CRP can be used as an adjunct in evaluating the tumor markers-CEA and SCC-Ag and may improve the clinical diagnosis and follow-up of EC patients, especially for ESCC subgroup.  相似文献   
108.
Background. Percutaneous vertebroplasty involves the injection of acrylic surgical cement into the vertebral body. The basic principles of vertebroplasty and the authors' own clinical experiences are described. Material and methods. Between November 1999 and January 2005 the authors performed percutaneous vertebroplasty on 75 patients: 45 with osteoporotic compression fractures, 15 with angiomas of the vertebral bodies, and 12 patients with spinal neoplasms. There were also 3 patients with coexisting spinal angiomas and osteoporotic compression fractures. All these patients were treated under local anesthesia. Cement injections were realized by the transpedicular approach under fluoroscopic guidance; in certain cases a CT-guided approach was used. The clinical outcome was assessed based on follow-up examinations, the Oswestry questionnaire, and the Visual Analog Pain Scale. Plain x-rays or CT scans were made for purposes of radiological evaluation. Results. Follow-up examinations revealed pain relief or significant reduction of pain in 89% of the patients. In 2 cases (3%) vertebroplasty was complicated by intracanal leakage of cement. Conclusions. Percutaneous vertebroplasty is well tolerated by patients. Filling with cement is effective in the treatment of osteoporotic compression fractures and of vertebral angiomas.  相似文献   
109.
The HPLC-SPE-NMR technique, supported by HPLC-MS measurements, was used to determine structures of major as well as some minor constituents of ethanol and petroleum ether extracts of Harpagophytum procumbens (Devil's claw) roots. This method was also shown to be applicable for rapid and precise on-line identification of secondary metabolites present in commercial herbal products of H. procumbens. A total of 15 compounds (1-14 and 17) were identified from the ethanol and petroleum ether extracts, including a novel Diels-Alder dimer 14. Optimization of the HPLC-SPE-NMR experiments included quantitative (1)H NMR measurements, determination of trapping and elution efficiency, effect of multiple trapping of analytes, use of various deuterated solvents for SPE cartridge elution, and effect of post-column dilution ratio of eluent with water. Linear accumulation of apolar and relatively polar analytes was demonstrated for at least 8-10 repeated trappings, resulting in greatly improved signal-to-noise ratios in NMR spectra and reduced acquisition times. Thus, the HPLC-SPE-NMR technique provides an efficient means of identification of multiple components of crude extracts. By allowing on-line generation of high-quality 2D NMR data without traditional purification of extract components, the HPLC-SPE-NMR methodology represents a paradigm shift in natural products research with respect to structure elucidation.  相似文献   
110.
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