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111.
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Extracorporeal membrane oxygenation (ECMO) is increasingly applied as rescue-therapy for patients with severe acute respiratory distress syndrome (ARDS). Here, we evaluate the effect of different configuration strategies (venovenous vs. venoarterial vs. veno-venoarterial) on the outcome. From 2006 to 2008, 30 patients received ECMO for severe ARDS. Patients were divided into three groups according to the configuration: veno-venous (vv; n = 11), venoarterial (va; n=8) or veno-venoarterial (vva; n = 11). Data were prospectively collected and endpoint was 30-day mortality. To identify independent risk factors, univariate analysis was performed for clinical parameters, such as age, body mass index, gender, configuration, low-pH, oxygenation index (pO(2)/FiO(2)) and underlying disease. Thirty-day mortality was 53% (n = 16) for all comers: 63% (n = 7) died in the vv-group, 75% (n = 6) in the va-group and 27% (n = 3) in the vva-group. Although univariate analysis could not rule out a significant predictor for the outcome, there was a trend visible to decreased mortality in the vva-group when compared to vv- and va-groups (27% vs. 63% vs. 75%; P = 0.057). ECMO provides a survival benefit in patients when considering a predicted mortality rate of 80% in ARDS. The configuration mode appears to impact the outcome as the veno-venoarterial appears to further improve the survival in this subset of patients.  相似文献   
113.
Whereas the "vertical" elements of the insect olfactory pathway, the olfactory receptor neurons and the projection neurons, have been studied in great detail, local interneurons providing "horizontal" connections in the antennal lobe were ignored for a long time. Recent studies in adult Drosophila demonstrate diverse roles for these neurons in the integration of odor information, consistent with the identification of a large variety of anatomical and neurochemical subtypes. Here we focus on the larval olfactory circuit of Drosophila, which is much reduced in terms of cell numbers. We show that the horizontal connectivity in the larval antennal lobe differs largely from its adult counterpart. Only one of the five anatomical types of neurons we describe is restricted to the antennal lobe and therefore fits the definition of a local interneuron. Interestingly, the four remaining subtypes innervate both the antennal lobe and the suboesophageal ganglion. In the latter, they may overlap with primary gustatory terminals and with arborizations of hugin cells, which are involved in feeding control. This circuitry suggests special links between smell and taste, which may reflect the chemosensory constraints of a crawling and burrowing lifestyle. We also demonstrate that many of the neurons we describe exhibit highly variable trajectories and arborizations, especially in the suboesophageal ganglion. Together with reports from adult Drosophila, these data suggest that wiring variability may be another principle of insect brain organization, in parallel with stereotypy.  相似文献   
114.
The aim of this study was to report the clinical features of a young athletic patient with bipartite patella, and review the literature to discuss the entity of this rare anomaly. In the course of an athletics competition, a 12-year-old top sportsman felt an intense pain around his left knee-cap while taking off from a jumping-board and broke down the competition. X-rays and magnetic resonance imaging showed an isolated distal pole of the patella with just minor diastasis; however, the X-rays did not suggest a recent fracture but rather hint at an atypically injured bipartite patella. A conservative therapy of 5 weeks with brace followed including a ban on sport activities for 12 weeks. Ten weeks later, the radiographs revealed a complete consolidation. Six months after the injury, MRI only presented a generally inconspicuous horizontal sclerosed structure. A fracture or separation of the bipartite patella was retrospectively diagnosed.  相似文献   
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Epidemiological studies suggest a link between fetal/early infant nutrition and adult coronary artery disease. In the present study, we examined the effects of altering nutrition during gestation, lactation and juvenile life on aortic structure and function in rats. Wistar rat dams were fed either a control or low-protein diet throughout pregnancy, or a low-protein diet for the final 7 days of gestation only. At 21 days post-partum, male pups were weaned on to a control, low-protein or high-fat diet. At 12 weeks, the offspring rats were killed. In 46 rats, aortic sections were mounted and stained to assess media thickness and elastin content. In a further 38 rats, aortic rings were suspended in an organ bath and vascular reactivity was tested with dose-response curves to the endothelium-dependent dilator acetylcholine and the endothelium-independent dilator sodium nitroprusside. Rats exposed to maternal protein restriction while in utero had a significantly decreased aortic wall thickness compared with control rats (P=0.005). Total elastin content of the aorta was also decreased by both maternal low-protein (P=0.02) and early postnatal low-protein (P=0.01) diets. Neither maternal nor postnatal low-protein or high-fat diets, however, resulted in any significant changes in arterial dilator function. In conclusion, fetal undernutrition in rats, induced via a maternal low-protein diet, causes a decrease in aortic wall thickness and elastin content without altering aortic dilator function. These changes in vascular structure may amplify aging-related changes to the vasculature and contribute to the pathophysiology of the putative link between impaired fetal growth and adult cardiovascular disease.  相似文献   
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118.
Statins decrease LDL cholesterol and the risk of atherosclerotic cardiovascular disease (CVD). They also decrease coenzyme Q10 (CoQ10), an effect that may negate some of the statin benefit on CVD. We examined the relationship between plasma CoQ10 concentration and CVD in a prospective case-control study of the effect of pravastatin. Plasma samples from 250 LIPID trial patients who over 6 years suffered a recurrent CVD event (CVD death, nonfatal MI or stroke) and 250 matched controls who remained event-free for the same duration of follow-up were assayed for CoQ10 and lipids (cholesterol and cholesterylesters). Mean plasma CoQ10 concentrations were significantly lower in pravastatin-treated patients than in those assigned placebo (0.51 versus 0.60 micromol/L, P = 0.006), and there was a moderate correlation between CoQ10 and common cholesterylesters (Pearson correlation coefficients in patients randomised to placebo, range r = 0.42-0.63). Univariate conditional logistic regression did not suggest any relationship between plasma CoQ10 and the risk of future CVD events (odds ratio 1.18; 95% CI 0.74-1.87; P = 0.49). Instead, we observed a reduction in the rate of recurrent CVD events with increasing ratio of plasma cholesterylarachidonate to cholesteryllinoleate. This study confirms that pravastatin lowers plasma CoQ10 concentrations, but this does not appear to predict the risk of recurrent CVD events.  相似文献   
119.
Patients are frequently told new information in the early postoperative period and may retain little of it. Two hundred patients undergoing general anaesthesia for day surgery procedures were randomly allocated into two equal groups, 'Early' and 'Late'. Both groups were asked to undertake a simple memory test either in the early or late postoperative phase of their recovery. A list of five objects was verbally presented and recall of these five objects was tested after 30 min. A control group of 100 patients performed the same test. Patients in the control group received no sedative medications. Statistically significant differences (p < 0.001) in recall ability were demonstrable between each of the three groups. Twenty-three percent of patients in the 'Early' group had total amnesia of any test information given. Only 1% of the 'Late' group were unable to remember any information; a mean interval of 40 min separated the two groups. We recommend that verbal information given postoperatively be delayed until a recovery interval of at least 40 in, and should be supported with written material.  相似文献   
120.
Analysis of untreated fresh blood plasma from healthy, fasting donors revealed that high density lipoprotein (HDL) particles carry most (approximately 85%) of the detectable oxidized core lipoprotein lipids. Low density lipoprotein (LDL) lipids are relatively peroxide-free. In vitro the mild oxidation of gel-filtered plasma from fasting donors with a low, steady flux of aqueous peroxyl radicals initially caused preferential oxidation of HDL rather than LDL lipids until most ubiquinol-10 present in LDL was consumed. Thereafter, LDL core lipids were oxidized more rapidly. Isolated lipoproteins behaved similarly. Preferential accumulation of lipid hydroperoxides in HDL reflects the lack of antioxidants in most HDL particles compared to LDL, which contained 8-12 alpha-tocopherol and 0.5-1.0 ubiquinol-10 molecules per particle. Cholesteryl ester hydroperoxides (CEOOHs) in HDL and LDL were stable when added to fresh plasma at 37 degrees C for up to 20 hr. Transfer of CEOOHs from HDL to LDL was too slow to have influenced the in vitro plasma oxidation data. Incubation of mildly oxidized LDL and HDL with cultured hepatocytes afforded a linear removal of CEOOHs from LDL (40% loss over 1 hr), whereas a fast-then-slow biphasic removal was observed for HDL. Our data show that HDL is the principal vehicle for circulating plasma lipid hydroperoxides and suggest that HDL lipids may be more rapidly oxidized than those in LDL in vivo. The rapid hepatic clearance of CEOOHs in HDL could imply a possible beneficial role of HDL by attenuating the build-up of oxidized lipids in LDL.  相似文献   
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