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661.
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Experimental animal data have indicated that the site of ventricular tachycardia origin and, hence, the degree of asynchronous contraction, may influence the hemodynamic tolerance during sustained ventricular tachycardia. However, data in man are scarce. We studied patients with preserved left ventricular function and absence of significant coronary artery disease. Ventricular tachycardia was simulated with rapid pacing (at 120 and 150 beats/min), performed randomly, from the right ventricular apex or the right ventricular outflow tract. Following pacing from one site, it was repeated from the alternate site. Compared to outflow tract pacing, QRS duration was significantly longer during rapid pacing from the apex. Left ventricular pressure was recorded using a micromanometer-tipped catheter. During sinus rhythm, peak systolic pressure was 142 ± 14 mmHg: at 120 beats/min, it decreased to 109 ± 12 mmHg during pacing from the apex and to 127 ± 21 mmHg during pacing from the outflow tract (P = 0.008). This difference diminished at 150 beats/min (101 ± 16 mmHg vs 112 ± 16 mmHg, respectively, P = 0.21). During sinus rhythm end-diastolic pressure was 13 ± 1 mmHg, which did not change significantly during pacing at 120 beats/min. During pacing at 150 beats/min, end-diastolic pressure increased to 21 ± 3 mmHg during pacing from the apex and to 16 ± 2 mmHg during pacing from the outflow tract (P = 0.005). Changes in first derivative of pressure and in isovolumic relaxation time constant were comparable during pacing from the two sites. Thus, it seems that tachycardias originating from the right ventricular outflow tract result in more favorable left ventricular hemodynamics, compared to those from the right ventricular apex  相似文献   
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664.
Summary Dental rehabilitation of edentulous patients with complete dentures includes not only aesthetics and mastication of food, but also speech quality. It was the aim of this study to introduce and validate a computer‐based speech recognition system (ASR) for automatic speech assessment in edentulous patients after dental rehabilitation with complete dentures. To examine the impact of dentures on speech production, the speech outcome of edentulous patients with and without complete dentures was compared. Twenty‐eight patients reading a standardized text were recorded twice – with and without their complete dentures in situ. A control group of 40 healthy subjects with natural dentition was recorded under the same conditions. Speech quality was evaluated by means of a polyphone‐based ASR according to the percentage of the word accuracy (WA). Speech acceptability assessment by expert listeners and the automatic rating of the WA by the ASR showed a high correlation (corr = 0·71). Word accuracy was significantly reduced in edentulous speakers (55·42 ± 13·1) compared to the control group’s WA (69·79 ± 10·6). On the other hand, wearing complete dentures significantly increased the WA of the edentulous patients (60·00 ± 15·6). Speech production quality is significantly reduced after complete loss of teeth. Reconstitution of speech production quality is an important part of dental rehabilitation and can be improved for edentulous patients by means of complete dentures. The ASR has proven to be a useful and easily applicable tool for automatic speech assessment in a standardized way.  相似文献   
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The study's aims are to explore ethnic differences in rates of adverse childhood experiences and lifetime traumatic events and in rates of psychiatric disorders for patients exposed to similar traumas. Rates of these events and rates of major depressive disorder, posttraumatic stress, substance use, and borderline personality disorders were compared among 506 non‐Hispanic Whites (N‐HW), 108 Latina(o)s, and 94 African Americans (AA) participating in the Collaborative Longitudinal Personality Disorder Study. We found that Whites reported higher rates of neglect than African Americans and Latina(o)s, higher rates of verbal/emotional abuse than African Americans, and higher rates of accidents and injuries/feared serious injury than Latina(o)s. African Americans had higher rates of seeing someone injured/killed than Whites. No significant interaction was observed between adverse events and ethnicity for mental disorders. © 2010 Wiley Periodicals, Inc. J Clin Psychol: 66:1–16, 2010.  相似文献   
667.
OBJECTIVE: Comorbidity among personality disorders is widely considered problematic. The validity of one proposed solution, diagnostic hierarchies, was investigated in the current study with respect to borderline, schizotypal, avoidant, and obsessive-compulsive personality disorders. METHOD: One approach used discriminant functions, derived from multiple psycho-social domains, that were used to classify comorbid individuals from the Collaborative Longitudinal Personality Disorder study (CLPS) to explore the possibility of hierarchical precedence of one personality disorder over another. A second approach examined the incremental increase in R(2)-value in predicting functioning and personality provided by each diagnosis over each other diagnosis. RESULTS: Obsessive-compulsive personality disorder was consistently subordinate to other diagnoses, whereas other indications of hierarchical relationships were domain-specific. CONCLUSION: Results indicate minimal support for an over-arching hierarchical pattern among studied personality disorders, and suggest the inclusion of all relevant diagnoses in clinical practice.  相似文献   
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669.
OBJECTIVE: This study was conducted to determine the interrater reliability and predictive validity of a set of diagnostic criteria for the prodrome of the first episode of schizophrenic psychosis when based on the Structured Interview for Prodromal Syndromes. METHOD: The subjects were patients referred for evaluation because of a suspected schizophrenia prodromal syndrome. For the reliability study, two to four raters independently diagnosed 18 patients on the basis of face-to-face or videotaped interviews. For the validity study, 6- and 12-month outcome data were collected for 29 patients. RESULTS: Agreement in differentiating prodromal from nonprodromal patients was 93%. The prodromal features had converted to schizophrenic psychosis for 46% of the prodromal patients at 6 months and for 54% at 12 months. CONCLUSIONS: In small groups of subjects, these diagnostic criteria for the schizophrenic prodrome and the Structured Interview for Prodromal Syndromes showed promising interrater reliability and predictive validity.  相似文献   
670.
OBJECTIVE: To evaluate performance characteristics of DSM-IV Personality Disorders (PDs) criteria. METHOD: Six hundred and sixty-eight adults recruited for the Collaborative Longitudinal Personality Disorders Study (CLPS) were assessed with diagnostic interviews. RESULTS: Within-category inter-relatedness was evaluated by Cronbach's alpha and median intercriterion correlations (MIC). Cronbach's alpha ranged from 0.47 to 0.87 (median=0.71); seven of the 10 PDs had alphas greater than 0.70. Between-category criterion overlap was evaluated by "inter-category" intercriterion correlations between all PD pairs (ICMIC). ICMIC values (median=0.08) were lower than MIC values (median=0.23). Diagnostic efficiency statistics (sensitivity, specificity, positive predictive power and negative predictive power were calculated for schizotypal, borderline, avoidant and obsessive-compulsive PDs. CONCLUSION: DSM-IV PD criteria sets have some convergent validity and discriminant validity: criteria for individual PDs correlate better with each other than with criteria for other PDs. Diagnostic efficiency statistics provide guidance regarding usefulness of criteria for inclusion or exclusion.  相似文献   
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