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51.
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Diffuse alopecia is mainly caused by telogen effluvium, diffuse androgenetic alopecia (female-pattern hair loss) and diffuse alopecia areata. Differential diagnosis between the three disorders may be difficult in several occasions. In this second part of our study, chronic telogen effluvium and diffuse alopecia areata are discussed in detail, including clinical, dermoscopic and histological aspects. A flowchart presents a practical and objective differential diagnostic approach to diffuse alopecia.  相似文献   
53.

Objectives

In Denmark, maternal mortality has been reported over the last century, both locally through hospital reports and in national registries. The purpose of this study was to analyze data from national medical registries of pregnancy-related deaths in Denmark 1985–1994 and to classify them according to the UK Confidential Enquiry into Maternal Deaths (CEMD).

Study design

All deaths of women with a registered pregnancy within 12 months prior to the death were identified by comparing the Danish medical registries, death certificates, and relevant codes according to International Classification of Diseases (ICD-10). All cases were classified using the UK CEMD classification. Cases of maternal death were further evaluated by an audit group.

Results

311 cases were classified. 92 deaths (29.6%) occurred ≤42 days after termination of pregnancy. Of these, 30 were classified as direct obstetric deaths, 30 as indirect obstetric deaths, and 32 as fortuitous deaths. Among the late pregnancy-related deaths (>42 days), 1 woman died from a direct obstetric cause, 46 from indirect causes, and 172 from fortuitous causes. Hypertensive disorders of pregnancy were the major cause of direct maternal deaths. The rate of maternal deaths constituted 9.8/100,000 maternities (i.e. the number of women delivering registrable live births at any gestation or stillbirths at 24 weeks of gestation or later).

Conclusion

This is the first systematic report on deaths in Denmark based on data from national registries. The maternal mortality rate in Denmark is comparable to the rates in other developed countries. Fortunately, statistics are low, but each case represents potential learning.Obstetric care has changed and classification methods differ between countries. Prospective registration and registry linkage seem to be a way to ensure completion. This retrospective study has provided the background for a prospective study on registration and evaluation of maternal mortality in Denmark.  相似文献   
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Background:We report on the outcomes in aged patients with severe, treatment-resistant depression or psychosis who were given ongoing outpatient continuation-maintenance ECT of varying duration to prevent remission and relapse following a successful course of acute ECT.Methods:A retrospective chart review of 58 consecutive patients of three Australian aged psychiatry services comparing the number and length of psychiatric admissions before and after the start of continuation-maintenance ECT.Results:Four patients had only one treatment and two received over 50 (mean 14.7). Five were still enrolled in a maintenance program two years later. In the two years after continuation-maintenance ECT started, admissions fell by 53% in number and 79% in duration compared with the previous two years. Within the actual treatment period which varied from one patient to another, admissions fell by 90% in number and 97% in duration compared with the same period beforehand.Conclusion:A treatment effect cannot be proven but the severity and chronicity of patients' conditions make placebo effects and spontaneous remission unlikely. Randomised, controlled trials are almost impossible in this setting and so carefully conducted reviews and case–control studies are still of value. Our findings suggest that continuation-maintenance ECT is effective in carefully selected patients at high risk of relapse.  相似文献   
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Clinical trials are the gold standard for generating reliable medical evidence. The biggest bottleneck in clinical trials is recruitment. To facilitate recruitment, tools for patient search of relevant clinical trials have been developed, but users often suffer from information overload. With nearly 700 coronavirus disease 2019 (COVID-19) trials conducted in the United States as of August 2020, it is imperative to enable rapid recruitment to these studies. The COVID-19 Trial Finder was designed to facilitate patient-centered search of COVID-19 trials, first by location and radius distance from trial sites, and then by brief, dynamically generated medical questions to allow users to prescreen their eligibility for nearby COVID-19 trials with minimum human computer interaction. A simulation study using 20 publicly available patient case reports demonstrates its precision and effectiveness.  相似文献   
58.
Despite its widespread clinical use, the precise mechanism of action of amiodarone (AMI) has not been completely defined. We examined the effects of AMI (20 micrograms/ml) on Vmax and on conduction velocity (theta) during longitudinal (LP) and transverse (TP) propagation with respect to fiber orientation, in 10 strips of uniform anisotropic epicardial muscle obtained from the left ventricle of adult canine hearts. Mean values +/- SEM (standard error of the mean) were calculated as normalized values (beat 50/beat 1) after 4 h of AMI superfusion at five different basic cycle lengths (BCL). Vmax decreased from 0.99 +/- 0.01 at a BCL of 5,000 ms to 0.43 +/- 0.03 at a BCL of 300 ms during LP. During TP, Vmax decreased from 0.99 +/- 0.01 at a BCL of 5,000 ms to 0.54 +/- 0.05 at a BCL of 300 ms. The differences in the relative changes between both directions at a BCL of 300 ms, as well as at intermediate values of 1,000, 500, and 400, were significant (p less than 0.01). theta during LP (theta L) was depressed from 0.99 +/- 0.01 at a BCL of 5,000 ms to 0.80 +/- 0.04 at a BCL of 300 ms. In contrast, theta during TP (theta T) did not change as the BCL was decreased. In consequence, theta L was significantly more depressed than theta T at BCLs shorter than 1,000 ms (p less than 0.05). Moreover, theta T after AMI was not statistically different from control at any BCL studied. The lack of depression of theta T associated with a marked depression of Vmax during either LP or TP suggests that in addition to its sodium channel blocking properties, AMI could produce a decrease in the effective axial resistivity.  相似文献   
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We evaluated the effect of lidocaine (5 micrograms/ml) on Vmax and conduction velocity during longitudinal and transverse propagation to fiber orientation in strips of uniform anisotropic ventricular muscle from adult canine hearts. Tissues were markedly anisotropic, with conduction velocities 3.2 times faster during longitudinal propagation than during transverse propagation to the long axis of the fibers, and with the greatest values of Vmax associated with the slowest conduction velocities. After addition of lidocaine, Vmax (normalized values with respect to control for each cycle length, expressed as mean +/- SEM) decreased from 0.99 +/- 0.02 at a cycle length of 1,000 ms to 0.86 +/- 0.02 at a cycle length of 300 ms during longitudinal propagation. During transverse propagation, Vmax decreased from 0.99 +/- 0.03 at a cycle length of 1,000 ms to 0.87 +/- 0.03 at a cycle length of 300 ms. The differences in the relative changes between both directions at these cycle lengths, as well as with intermediate values of 500, 400, and 350 ms, were not significant. Similar results were obtained for conduction velocity. We conclude from these findings that under these experimental conditions the effects of lidocaine are characterized by a relative change both in Vmax and conduction velocity that is almost the same during longitudinal and transverse propagation at all cycle lengths explored. Moreover, the rapid binding-rate constants reported for lidocaine may play a significant role in determining the characteristics of Vmax and conduction velocity depressions in both directions.  相似文献   
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