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141.
142.
The epidemiology and prevention of alcohol problems were advanced significantly by the discovery of the important relationships among alcohol availability, per capita consumption and alcohol-related problems such as cirrhosis. Recently, however, alcohol-related problems have declined in some areas more than would be predicted by changes in consumptions. These declines may represent important opportunities for understanding the prevention of alcohol problems. For example, in recent work we have observed associations between declines in cirrhosis rates and increases in treatment for alcohol abuse and AA membership. The opportunities and challenges in examining the effects of various prevention measures on aggregate problem data are discussed. 相似文献
143.
A total of 52 of 238 patients (22%) with non-Hodgkin's lymphoma presented with disease in a primary extranodal site. The gastrointestinal tract was the commonest site involved (50%) and diffuse large cell was the commonest histological sub-type of the lymphoma (64%). Survivorship analysis of these patients, treated predominantly with chemotherapy, suggests that long-term survival is associated with: low-grade malignancy--median survival greater than 120 months; localized disease or spread of disease confined to the regional lymph nodes--median survival 65.5 months; and the use of aggressive combination chemotherapy for intermediate grade malignancy when the disease is localized or spread is confined to the regional lymph nodes--median survival greater than 110 months. 相似文献
144.
The role of catalase on Saccharomyces cerevisiae replicative lifespan was investigated using a wild-type haploid laboratory yeast W303a, a catalase A mutant, a catalase T mutant and an acatalasaemic mutant. Lifespan analysis was performed in two different environmental conditions. Under repressing conditions, on glucose media, catalase T activity, but not catalase A activity was necessary to assure longevity. However, under derepressing conditions, on ethanol media, both catalases were required for longevity assurance. Although catalase activity and carbon source influence yeast lifespan, the relationship between oxidative defence and replicative senescence is complex. 相似文献
145.
Hourly gastric aspiration has commonly been used to assess the efficacy of antisecretory compounds. We have compared continuous ambulatory 24-hour pH monitoring using a radiotelemetry capsule with standard nasogastric aspiration. Eight studies were performed on four male duodenal ulcer patients in remission receiving either placebo or an antisecretory agent. A significant correlation was found between capsule and aspirate pH measurements (r = 0.88, p less than 0.01). Radiotelemetry capsule measurements clearly showed the onset of action of an antisecretory drug, and the buffering effect of food. Radiotelemetric pH monitoring is shown to be as good as gastric sampling in the measurement of 24-hour intragastric acidity, allows continuous measurement of pH during normal activity and can accurately assess the effect of drugs on gastric acidity. 相似文献
146.
Thallium circumferential profiles in the detection of coronary artery disease--assessment by receiver operating characteristic curve analysis 总被引:2,自引:0,他引:2
Thallium uptake and redistribution in the myocardium was quantitated using circumferential activity profiles. The profiles were determined from images in the LAO 35, LAO 70 and anterior views, obtained after peak exercise and after 3-4 h redistribution. A retention curve was constructed from these profiles, displaying the redistribution profile as a fraction of the stress profile. Normal values were obtained from 21 normal patients and compared to the images from 68 patients suspected of having coronary artery disease (CAD). Of the latter, 20 had normal/non-significant CAD and 48 had 70% or greater stenosis of one or more vessels on coronary angiography. Several methodological variations were examined: calculation of the profiles using the peak or average counts around the ventricle, uniform or interpolative background subtraction, normalisation of the profiles to their peak or mean counts. Receiver operating characteristic (ROC) curves were generated for profiles calculated using these variations and compared with the ROC curves obtained by visual interpretation of both analogue and computer-enhanced images by two experienced observers. The uniform background subtraction method was found to be better than the interpolative method, and normalisation to the mean of each curve was preferable to normalisation to the peak. ROC curves using profiles calculated using the peak myocardial counts were identical to the ROC curves from profiles using the average counts, but the operating points on the two curves differed. Computer enhancement of the digital images resulted in increased sensitivity for CAD without loss of specificity when compared to the interpretation of the analogue images. The circumferential profiles were found to provide a further increase in sensitivity and were highly reproducible.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
147.
I.H.M. Smart 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(1):28-48
In the mouse the release of neocortical neurons from the periventricular germinal layers of the forebrain commences towards the ventral margin of the lateral pallium at the level of the interventricular foramen and is propagated from there across the lateral wall of the hemisphere. In the adult cortex the origin of the gradient corresponded to the ventral portion of the somatotopic map of the body, that is, to the area representating structures derived from the embryonic branchial arches, namely, the peri‐oral region and laryngo‐pharyngeal masticatory apparatus. Branchial arch nerves also innervate the fore‐ and mid‐gut and all the related exocrine and endocrine glands. This suggests that the mammalian neocortex evolved from a visceral integration area in a positionally equivalent area in the pallium of a reptilian ancestor which expanded in relation to extensive changes taking place in the visceral and branchial systems of the body during the transition from reptilian ectothermy to mammalian endothermy. The practical problem facing early mammals was to acquire and process the extra energy required to sustain a continuously high metabolic rate. Improvements to the food processing capabilities of the visceral and branchial systems and the expansion of their neural control were important components in the conglomerate of changes required to sustain the increased energy demands of endothermic tissues. Endothermy also bestowed the ability to sustain greater numbers of metabolically expensive neurons and this, in turn, required an appropriate response from the cell production mechanisms in the periventricular germinal layers. Anat Rec, 291:28–48, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
148.
149.
Dunnick NR; Svetkey LP; Cohan RH; Newman GE; Braun SD; Himmelstein SI; Bollinger RR; McCann RL; Wilkinson RH Jr; Klotman PE 《Radiology》1989,171(1):219-222
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension. 相似文献
150.
Jaundice develops in many patients with liver metastases from colorectal adenocarcinoma during hepatic arterial infusion chemotherapy (HAIC). The usual cause is thought to be hepatotoxicity from the chemotherapeutic agent or biliary obstruction from progressive neoplastic disease. The authors evaluated the abdominal computed tomography and ultrasound examinations performed on 49 patients who were jaundiced during long-term HAIC. In only one patient was diffuse intrahepatic biliary dilatation caused by an obstructing mass in the porta. Two patients had metastatic hepatic lesions causing focal biliary obstruction. Intrahepatic dilatation without an obstructing mass occurred in 20 patients. Percutaneous or endoscopic cholangiograms were commonly interpreted prospectively as showing extrinsic compression by metastases, but no mass was confirmed on imaging studies. Seven patients had focal intrahepatic ductal dilatation from stricture without an associated mass. The remaining 19 patients had normal-caliber ducts; their jaundice was caused by chemical hepatitis. This series suggests that the most common causes of jaundice in these patients are chemical hepatitis and common bile duct stricture, complications of intraarterial chemotherapy, rather than neoplastic obstruction. Stricture formation may be confused with extrinsic compression on direct cholangiograms. 相似文献