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81.
Temperament of preterm versus full-term infants   总被引:4,自引:0,他引:4  
The temperament of a group of preterm infants (n = 126) was studied as part of a large, longitudinal study of infant temperament and behavior in a representative sample of Australian infants (n = 2443). Utilizing the Infant Temperament Questionnaire of Carey and McDevitt, previously revised and validated for an Australian population, ratings were made at 4 to 8 months corrected age, and data for the preterm group (less than 37 weeks gestation) were compared to those infants born at term (37 to 41 weeks). There were no significant differences between the two groups on any of the sociodemographic variables, on the mother's global rating of temperament, or on the reported incidence of colic, sleep problems, and excessive crying. There were also no differences between premature and full-term infants on any of the individual dimensions or clinical categories of temperament. We conclude that prematurity per se does not affect observed temperament at 4 to 8 months. However, we cannot extend these conclusions to high-risk infants who experience medical complications of prematurity, and who require intensive care for prolonged periods of time. These may represent an entirely different category of risk for subsequent difficult temperament and behavior problems.  相似文献   
82.
The DSM III category of Attention Deficit Disorder with Hyperactivity is considered within a framework of Rutter's (1977) outline of criteria for adequacy of psychiatry classification. Discussion of problems with the operationalization and definition of 'attention deficit' and the difficulty of using this rubric in distinguishing between ADDH and other related childhood disorders, along with the consequent failure to meet other important criteria, leads to the conclusion that the concept needs re-appraisal.  相似文献   
83.
In national health services, where there is a tendency towards a lack of resources and a continuous increase in demand, it is necessary to implement decisions that promote efficiency. In this paper we focus on potential diversification economies as a strategy to increase efficiency levels. We evaluate the change in efficiency in Catalan hospitals between 1987 and 1992, and analyse the presence of possible diversification economies in each hospital. We use Data Envelopment Analysis, which does not need information on either input or output prices. The results are that the majority of hospitals could increase their efficiency and reduce their costs by diversification to the output-mix offered. Potential productivity gains are between 29% and 46%. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
Evidence from our laboratory with the use of cultured (primary and passaged) cells has extended our initial observation that human uterine fibroid is an extrapituitary source of prolactin. Fibroid prolactin antigen in conditioned medium reacted specifically in radioimmunoassay for human pituitary prolactin. Control experiments demonstrated that the radioimmunoassay results were not spurious due to degradation of tracer 125I-labeled prolactin. Immunoparallel dilution curves indicated antigenic relatedness of pituitary and fibroid prolactin. In a calibrated Sephadex G-100 column, fibroid prolactin eluted in the same region (20.3 to 20.9 kd) as purified pituitary prolactin. Glycosylated prolactin, detected by concanavalin A affinity column chromatography, appeared to constitute only a small percentage of fibroid prolactin made in culture. The ratio of fibroid prolactin bioactivity (lactogen Nb2 lymphoma bioassay) to antigen (radioimmunoassay) was 0.77. These data indicate that human uterine fibroid tissue produces a molecule similar to or, perhaps, identical with pituitary prolactin.  相似文献   
85.
ABSTRACT. The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed ( r =0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values.  相似文献   
86.
A revised validated version of the Toddler Temperament Scale (TTS) was used to develop normative data for temperament in Australian toddlers. Results confirm the accepted practice of dividing the group into younger and older toddlers, with normative data reported for those younger and older than 24 months. The TTS can be used above the normal cut-off age of 36 months. Care must be taken with interpretation of temperament scores, especially when comparing children of different backgrounds.  相似文献   
87.
A convenience sample of 240 infants aged 4-8 months was studied to evaluate the suitability of a revised version of Carey's Infant Temperament Questionnaire (ITQ) for an Australian population. Data analyses indicated all item/dimension correlations significant at P less than 0.01 or better, satisfactory internal consistency of the instrument as measured by alpha coefficients, and test retest reliability of 0.79. Infants rated as having a 'difficult' temperament were significantly more likely to be reported as having problem behaviours. Significant differences were found between Australian and American infants on three of the nine temperament dimensions - rhythmicity, activity and intensity. The results of this study indicate that this revised ITQ is suitable for use with Australian infants.  相似文献   
88.
BACKGROUND: Newer contrast agents as well as tissue harmonic imaging enhance left ventricular (LV) endocardial border delineation, and therefore, improve LV wall-motion analysis. Interpretation of dobutamine stress echocardiography is observer-dependent and requires experience. This study was performed to evaluate whether these new imaging modalities would improve endocardial visualization and enhance accuracy and efficiency of the inexperienced reader interpreting dobutamine stress echocardiography. METHODS AND RESULTS: Twenty-nine consecutive patients with known or suspected coronary artery disease underwent dobutamine stress echocardiography. Both fundamental (2.5 MHZ) and harmonic (1.7 and 3.5 MHZ) mode images were obtained in four standard views at rest and at peak stress during a standard dobutamine infusion stress protocol. Following the noncontrast images, Optison was administered intravenously in bolus (0.5-3.0 ml), and fundamental and harmonic images were obtained. The dobutamine echocardiography studies were reviewed by one experienced and one inexperienced echocardiographer. LV segments were graded for image quality and function. Time for interpretation also was recorded. Contrast with harmonic imaging improved the diagnostic concordance of the novice reader to the expert reader by 7.1%, 7.5%, and 12.6% (P < 0.001) as compared with harmonic imaging, fundamental imaging, and fundamental imaging with contrast, respectively. For the novice reader, reading time was reduced by 47%, 55%, and 58% (P < 0.005) as compared with the time needed for fundamental, fundamental contrast, and harmonic modes, respectively. With harmonic imaging, the image quality score was 4.6% higher (P < 0.001) than for fundamental imaging. Image quality scores were not significantly different for noncontrast and contrast images. CONCLUSION: Harmonic imaging with contrast significantly improves the accuracy and efficiency of the novice dobutamine stress echocardiography reader. The use of harmonic imaging reduces the frequency of nondiagnostic wall segments.  相似文献   
89.
90.
Human bladder cancer may be caused by exposure to aromatic amines. The polymorphic enzyme N-acetyltransferase 2 (NAT2) is involved in the metabolism of these compounds. Two classical studies on chemical workers in Europe, exposed in the past to aromatic amines like benzidine, unambiguously showed that the slow acetylator status is a genetic risk factor for arylamine-induced bladder cancer. In the former benzidine industry in Huddington, Great Britain, 22 of 23 exposed cases with bladder cancer, but only 57% of 95 local controls without bladder cancer were of the slow acetylator phenotype. In Leverkusen, Germany, 82% of 92 benzidine-exposed chemical workers with bladder cancer were of the slow acetylator phenotype, whereas only 48% of 331 chemical workers who had worked at that plant were of the slow acetylator phenotype. This is in line with several smaller studies, which also show an over-representation of the slow acetylator status in formerly arylamine-exposed subjects with bladder cancer. Some of these studies included also subjects that were exposed to aromatic amines by having applied dyes, paints and varnishes. These European findings are in contrast to a large study on Chinese workers occupationally exposed to aromatic amines. In this study, only five of 38 bladder cancer cases occupationally exposed to arylamines were of the slow acetylator genotype. This is much lower than the ratio of slow acetylators to the general population in China. This points to different mechanisms of susceptibility for bladder cancer upon exposure to aromatic amines between European (Caucasian) and Chinese populations.  相似文献   
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