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991.
992.
Four cases of intracardiac fungal masses occurred over 2 y amongst 7 cases of systemic candidiasis in a neonatal referral unit. The gestations and birthweights were 25, 23, 24 and 30 wk and 805, 605, 640 and 1395 g, respectively. The pedunculated, solitary right atrial masses were detected 2-17 d after diagnosing candidemia in 3 cases, whereas it was the presenting feature in the 4th. All had indwelling right atrial catheters and received multiple courses of broad-spectrum antibiotics. The masses were removed successfully in two cases fit for surgery. None survived despite antifungal therapy, including liposomal amphotericin B at 6 mg/kg/d. Early introduction of enteral feeds, minimization of prolonged exposure to broad-spectrum antibiotics and judicious use of central catheters may reduce the incidence of systemic candidiasis in high-risk neonates. Surveillance echocardiography and timely surgical intervention may reduce the mortality and/or morbidity related to intracardiac fungal masses.  相似文献   
993.
Fatigue phenomena, which appear generally below the yield stress, is the cause of more than 80% of in-service mechanical failures. However, the optimization of the weight and cost when designing mechanical components or structures, linked to improved performance, leads to increasingly stressed components. Therefore, a fatigue design approach must be done by the engineer. This paper shows the experience gained over five academic years of teaching fatigue, the assessment of automotive components using a reliability approach to predict probability of failure, in the engineering school, Arts et Métiers ParisTech, in France. The choice was made to present a comprehensive fatigue assessment approach using a method, initially developed in the automotive industry and since extended to the aeronautical and mechanical industries. This method is known as the “stress–strength interference analysis”. The “stress” represents the distribution of the driver severity, and the “strength” represents the distribution of the fatigue strength of all the components. A suspension arm is used to illustrate the approach. The Dang Van multi-axial fatigue criterion is implemented in a finite-element code and a danger coefficient is visualized on the meshed structure. The fatigue analysis is interpreted with respect to the target reliability sought by the car manufacturer.  相似文献   
994.
995.
In this article, we propose an automatic algorithm for coronary artery segmentation from 3D X-ray data sequences of a cardiac cycle (3D-CT scan, 64 detectors, 10 phases). This method is based on recent mathematical morphology techniques (some of them being extended in this article). It is also guided by anatomical knowledge, using discrete geometric tools to fit on the artery shape independently from any perturbation of the data. The application of the method on a validation dataset (60 images: 20 patients in 3 phases) led to 90% correct (and automatically obtained) segmentations, the 10% remaining cases corresponding to images where the SNR was very low.  相似文献   
996.
目的:新辅助疗法可以降低全直肠系膜切除术后患者局部直肠癌的复发率。本研究的目的是评价多层CT鉴别直肠癌UICCI期和UICCⅡ~Ⅳ的准确性和可靠性。方法:29例患者术前行腹部MSCT门静脉期扫描。采用双盲法,由两位阅片者分别在专门的工作站上进行横轴面和冠状面图象重组,对局部肿瘤的范围(T)、淋巴结情况(N)、及远处转移(M)进行评估,  相似文献   
997.
Objectives(1) To quantify night-to-night variability in sleep behaviors and sleep measures among older chronic insomnia (CI) subjects and non-insomnia (NI) controls; (2) to investigate systematic temporal patterns of sleep behaviors and sleep measures across nights; and (3) to examine clinical correlates of sleep variability.MethodsSixty-one older adults with CI (71.4 years old, 67% F) and 31 older adults with NI (70.7 years old, 65% F) completed questionnaires, kept sleep diaries and wore wrist actigraphs for 2 weeks. Mixed models were used to estimate within-subject mean and standard deviation values; these were then compared across groups. Mixed models were also used to determine associations across nights of sleep measures.ResultsCI and NI differed on mean values for clinical ratings and sleep diary measures, but not for actigraphy measures. CI also showed significantly greater variability than NI on most sleep diary measures and on actigraphically measured wakefulness after sleep onset (WASO) and sleep efficiency. Among CI, neither diary nor actigraphy measures from one night correlated with values from the previous night. Diary WASO, sleep time, actigraphy sleep latency and sleep time, however, positively correlated with values from the previous two nights. Variability measures were not correlated with other global clinical measures among CI.ConclusionsCompared to NI, older adults with CI report worse sleep and greater night-to-night variability, which was confirmed with actigraphy. There was little evidence for positive or negative correlation of sleep measures across nights. Variability of sleep may be an important target for insomnia treatments.  相似文献   
998.
Seventeen patients underwent MRI spin-echo imaging (Magniscan 5000) 7 to 21 days after acute myocardial infarction (10 anterior, 7 inferior--average 13.1 +/- 3.7 days). The success rate of visualisation of AMI evaluated independently by a qualitative score (from 0 to 4) based on the brilliance of the myocardial signal after taking steps to eliminate the brillance of pericardial fat and subendocardial flow signals, was 3.1 +/- 0.87 in anterior AMI (10 out of 10) and 1.28 +/- 1.25 (4 out of 7) in inferior AMI (p less than 0.007). The diagnostic sensitivity was increased when images of the third echo were used (13 out of 17) compared to those of the second echo (8 out of 17, p less than 0.016). The value of the 3rd echo is explained and emphasised. Abnormal intramyocardial signals were not recorded in a control group of 10 patients under similar conditions of multi-echo imaging. Finally, significant correlations were observed between peak CPK concentrations and the MRI score (r = 0.62; p less than 0.01) and between peak CPK and the number of sections in which the hyperbrilliant signal was observed (r = 0.74; p less than 0.001): this may open the day to quantification of myocardial necrosis by MRI.  相似文献   
999.
Hyponatremia due to the syndrome of inappropriate antidiuresis rather than due to isotonic hyponatremia from hyperproteinemia developed in a patient with Waldenström's macroglobulinemia. The patient was unable to excrete a water load normally despite suppression of antidiuretic hormone to normal levels. The temporal relationship between control of the tumor and resolution of the hyponatremia suggests that the tumor either produced a substance that enhanced the hydroosmotic effect of endogenous antidiuretic hormone or produced an antidiuretic substance immunologically different from antidiuretic hormone. The syndrome of inappropriate antidiuresis should be suspected in hyponatremic patients with Waldenström's macroglobulinemia.  相似文献   
1000.
Posttraumatic stress disorder (PTSD) is a prevalent disorder that is associated with poor clinical and health outcomes, and considerable health care utilization and costs. Recent estimates suggest that 5-20% of military personnel who serve in current conflicts in Iraq and Afghanistan meet diagnostic criteria for PTSD. Clinically, sleep disturbances are core features of PTSD that are often resistant to first-line treatments, independently contribute to poor daytime functioning, and often require sleep-focused treatments. Physiologically, these observations suggest that PTSD is partially mediated by sleep disruption and its neurobiological correlates that are not adequately addressed by first-line treatments. However, polysomnographic studies have provided limited insights into the neurobiological underpinnings of PTSD during sleep. There is an urgent need to apply state-of-the-science sleep measurement methods to bridge the apparent gap between the clinical significance of sleep disturbances in PTSD and the limited understanding of their neurobiological underpinnings. Here, we propose an integrative review of findings derived from neurobiological models of fear conditioning and fear extinction, PTSD, and sleep-wake regulation, suggesting that the amygdala and medial prefrontal cortex can directly contribute to sleep disturbances in PTSD. Testable hypotheses regarding the neurobiological underpinnings of PTSD across the sleep-wake cycle are offered.  相似文献   
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