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151.
BACKGROUND: Three-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) are known to attenuate myocardial ischemia-reperfusion (IR) injury. Fluvastatin (FV) has a potent free radical scavenging action, but it is unclear whether the timing of FV administration could affect its cardioprotective effect or if the antioxidant property of FV might attenuate IR injury. METHODS AND RESULTS: IR was induced in rats by left coronary artery occlusion for 30 min followed by 24-h reperfusion. The rats were divided into 4 groups: oral FV group (10 mg/kg per day for 2 weeks before ischemia); iv, FV group (10 mg/kg) before ischemia; iv, FV group (10 mg/kg) before reperfusion; and control group. Oxidative stress was evaluated by myocardial 8-hydroxydeoxyguanosine (8-OHdG) content. The area at risk did not different among the 4 groups. Pretreatment with FV for 2 weeks significantly reduced the infarct size by 28% as compared with the control group, but FV administered just before ischemia or reperfusion did not. Myocardial 8-OHdG content was not affected by FV. The infarct-sparing effect of FV was completely abolished by N(omega)-nitro-l-arginine methyl ester or wortmannin. CONCLUSIONS: The present results indicate that pretreatment with FV, but not just before ischemia or reperfusion, attenuates IR injury primarily through the nitric oxide pathway, not through its antioxidant property.  相似文献   
152.
Summary Conclusion. Near-infrared spectrometry is a new, rapid, and accurate method for measuring fecal fat that does not require a great deal of chemical knowledge and that can be used by anyone. This method is considered indispensable for the diagnosis of pancreatic steatorrhea and treatment follow-up. Methods. Fecal fats (GLC method, van de Kamer method), neutral sterols (GLC method), bile acids (GLC method) and short-chain fatty acids (HPLC method) were assayed by the respective conventional methods in 120 subjects, including patients with pancreatic dysfunction, and the results were compared with the those obtained by near-infrared spectrometry. The correlations between fecal fat excretion measured by the GLC method (x) and van de Kamer method (x) and by near-infrared spectrometry (y) were expressed by y=1.10 x-0.16 (r=0.949, P<0.01) and y=0.750x+1.654 (r=0.930, p<0.01), respectively. Results. The sensitivity and specificity of near-infrared spectrometry for fecal fats were 94.9 and 98.2%, respectively, when compared with the GLC method, and 87.5 and 90.0%, respectively, when compared with the van de Kamer method. In contrast, near-infrared spectrometry was not nearly as accurate as the conventional methods for determining neutral sterols, bile acids, and short-chain fatty acids.  相似文献   
153.
Background Both thrombolytic therapy and coronary angioplasty have been inconsistent together for primary acute myocardial infarction (AMI) therapy, because conventional thrombolytic agents accelerate plasminogen activator inhibitor-1 (PAI-1) activity. However, combining newly developed mutant tissue-type plasminogen activators with coronary angioplasty should be reconsidered. Methods This study was designed to investigate clinical usefulness of such an agent, monteplase, for treatment of AMI in light of PAI-1 kinetics. One hundred fifty-four consecutive patients with AMI were randomly assigned to receive direct coronary angioplasty (Group I) or coronary angioplasty after pretreatment with intravenous monteplase (Group II). In 90 of these patients, total PAI-1 antigen levels were serially measured. Results Baseline PAI-1 levels at admission were higher in patients with occluded infarct-related arteries than in patients with patent arteries in Group I (39 ± 4 vs 20 ± 2 ng/mL, P < .01) and in Group II (36 ± 3 vs 27 ± 2 ng/mL, P < .05). In the high PAI-1 level subgroup (≥27 ng/mL, n = 53), Group II showed a higher patency rate than Group I (56 vs 18%, P < .01). Multiple logistic regression analysis indicated that patency could be predicted by the PAI-1 level in Group I (Wald χ2= 3.94, P = .02, odds ratio 0.924, 95% CI 0.855-0.999), but not in Group II. Serial change patterns in the PAI-1 level were identical in Group I and Group II. Conclusion Because monteplase can be used independently of PAI-1 kinetics, a combination of monteplase administration at a community hospital with prompt transfer to a tertiary center for coronary intervention may be a powerful strategy for AMI. (Am Heart J 2002;144:e5.)  相似文献   
154.
OBJECTIVES: We sought to evaluate the effects of spironolactone on cardiac sympathetic nerve activity and left ventricular (LV) remodeling in patients with dilated cardiomyopathy (DCM). BACKGROUND: Aldosterone prevents the uptake of norepinephrine and promotes structural remodeling of the heart. Spironolactone, an aldosterone receptor blocker, improves LV remodeling in patients with DCM, but its influence on cardiac sympathetic nerve activity has not been determined. METHODS: We selected 30 patients with DCM who were treated with an angiotensin-converting enzyme inhibitor and a loop diuretic. Fifteen patients were assigned to receive spironolactone additionally, whereas the remaining 15 patients continued their current regimen. The delayed heart/mediastinum (H/M) count ratio, delayed total defect score (TDS), and washout rate (WR) were determined from iodine-123 ((123)I)-meta-iodobenzylguanidine (MIBG) images before and six months after treatment. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were determined by echocardiography, and New York Heart Association (NYHA) functional class was estimated.RESULTS: In the spironolactone group, the TDS decreased from 36 +/- 9 to 24 +/- 13 (p < 0.0001), the H/M ratio increased from 1.64 +/- 0.20 to 1.86 +/- 0.27 (p < 0.0001), and WR decreased from 55 +/- 12% to 41 +/- 15% (p < 0.0005). In addition, the LVEDV decreased from 187 +/- 26 to 154 +/- 41 ml (p < 0.005), and LVEF increased from 33 +/- 6% to 39 +/- 6% (p < 0.005). However, there were no significant changes in these parameters in the control group. There was a significant correlation between changes in the (123)I-MIBG findings and changes in LVEDV with spironolactone treatment (TDS: r = 0.684, p = 0.0038; H/M ratio: r = -0.878, p < 0.0001; and WR: r = 0.737, p = 0.0011). The NYHA functional class improved in both groups but showed a greater improvement in the spironolactone group than in the control group (p < 0.01). CONCLUSIONS: Spironolactone improves cardiac sympathetic nerve activity and LV remodeling in patients with DCM.  相似文献   
155.
Isolated brain-retrocerebral neurohemal complex of the silkworm of Bombyx mori was stimulated electrically and the released bombyxin (an insulin-like neuropeptide) was measured using time-resolved fluoroimmunoassay. The amount of bombyxin release depended on the number of stimulus pulses delivered to the axonal tract of the bombyxin-producing (BP) neurosecretory cells, and 17 fg of bombyxin per pulse was released from a cell. The titer of bombyxin in the hemolymph of bombyxin-II injected pupae decreased exponentially, the half-life being 170 min. To relate firing activity of a population of BP cells to the hormone titer in the hemolymph, bombyxin titer and its change in the hemolymph were calculated numerically. We assumed that the amount of bombyxin release was proportional to the firing rate of BP cells and the released bombyxin was inactivated with the same time course of injected bombyxin. Our calculations suggested that the hemolymph bombyxin titer may fluctuate dynamically and the mean titer is 380 pg/ml, a level which is close to the actually determined bombyxin titer at middle stages of pupal-adult development.  相似文献   
156.
Situs inversus totalis (SIT) is a rare congenital anomaly. Generally, laparoscopic surgery is difficult to perform in patients with SIT because of both the potential challenges associated with unexpected vascular anomalies and the lack of standardized strategy for handling such cases. This is the first report of laparoscopic total gastrectomy with lymph node dissection for advanced gastric cancer in a patient with SIT. A 79‐year‐old man with SIT was diagnosed with advanced gastric cancer. We performed laparoscopic total gastrectomy with modified D2 lymph node dissection (D2 without splenectomy) and esophagojejunal anastomosis using an overlap method involving retrocolic Roux‐en‐Y reconstruction. The total operating time was 232 min, and blood loss was 110 mL. There were no postoperative complications. In summary, laparoscopic total gastrectomy for gastric cancer can be performed safely, even in a patient with SIT.  相似文献   
157.
Several studies have demonstrated that MgH2 is a promising conversion-type anode toward Li. A major obstacle is the reversible capacity during cycling. Electrochemical co-existence of a mixed metal hydride-oxide conversion type anode is demonstrated for lithium ion batteries using a solid-state electrolyte. 75MgH2·25CoO anodes are obtained from optimized mixing conditions avoiding reactions occurring during high-energy ball-milling. Electrochemical tests are carried out to investigate the cycling capability and reversibility of the on-going conversion reactions. The cycling led to formation of a single-plateau nanocomposite electrode with higher reversibility yield, lowered discharge–charge hysteresis and mitigated kinetic effect at high C-rate compared to MgH2 anodes. It is believed that reduced diffusion pathways and less polarized electrodes are the origin of the improved properties. The designed composite-electrode shows good preservation and suitability with LiBH4 solid electrolyte as revealed from electron microscopy analyses and X-ray photoelectron spectroscopy.

The findings point to a means of guided formation of MgH2–CoO conversion-type nanocomposite electrode for all-solid-state Li-ion batteries.  相似文献   
158.
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients.  相似文献   
159.
160.
The Directigen Flu A + B kit, a rapid diagnostic device for influenza virus A and B was evaluated. The nasopharyngeal aspirates were obtained from 239 patients who visited our hospital, between January and March, 2000, presenting flu-like symptoms. Influenza virus AH1: 77 and AH3: 51 were isolated from 128 specimens and none from 111 specimens. Directigen Flu A + B showed 115 specimens positive and 106 specimens negative. The sensitivity and specificity of this kit were 89.8% (115/128) and 95.5% (106/111) compared with viral isolation. Agreement on positive and negative interpretations between Direction Flu A and this kit was 97.9% (234/239). In the evaluation of this kit for influenza B virus, 60 frozen nasopharyngeal aspirates collected from February to April, 1999 were used. The sensitivity and specificity of this kit were 88.9% (16/18) and 88.1% (37/42) compared with viral isolation. Agreement on positive and negative interpretations between FLU OIA and this kit was 91.7% (55/60). The Directigen A + B demonstrated sensitivity and specificity equivalent to the conventional kits in nasopharingeal aspirates. This kit can also differentiate influenza A and B viruses, a feature which is useful for treatment using anti-viral agents such as amantadine and neuraminidase inhibitor. To date, the kit is the most effective tool for the rapid diagnosis of influenza.  相似文献   
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