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31.
Russian forms of electrical stimulation became popular to a large extent as a result of the activities of Kots, who claimed force gains of up to 40% in elite athletes as a result of what was then a new form of stimulation. He did not provide details of his published work, nor did he give references. Russian electrical stimulation became popular despite the lack of research in the English-language literature. No studies published in English examined whether the "10/50/10" treatment regimen (10 seconds of stimulation followed by 50 seconds rest, repeated for 10 minutes) advocated by Kots is optimal, and only one study addressed whether maximum muscle torque was produced at an alternating current frequency of 2.5 kHz. The few studies that compared low-frequency monophasic pulsed current and Russian electrical stimulation are inconclusive. This article reviews and provides details of the original studies by Kots and co-workers. The authors contend that these studies laid the foundations for the use of Russian forms of electrical stimulation in physical therapy. The authors conclude that there are data in the Russian-language literature that support the use of Russian electrical stimulation but that some questions remain unanswered. 相似文献
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Federico Pappalardo Martina Crivellari Ambra L. Di Prima Nataliya Agracheva Malgorzata Celinska-Spodar Rosalba Lembo Daiana Taddeo Giovanni Landoni Alberto Zangrillo 《Intensive care medicine》2016,42(11):1706-1714
Purpose
To determine whether protein C zymogen (protein C concentrates or human protein C) improves clinically relevant outcomes in adult patients with severe sepsis and septic shock.Methods
This is a randomized, double-blind, placebo-controlled, parallel-group trial that from September 2012 to June 2014 enrolled adult patients with severe sepsis or septic shock and high risk of death and of bleeding (e.g., APACHE II greater than 25, extracorporeal membrane oxygenation or disseminated intravascular coagulopathy). All patients completed their follow-up 90 days after randomization and data were analyzed according to the intention-to-treat principle. Follow-up was performed at 30 and 90 days after randomization. The primary endpoint was a composite outcome of prolonged intensive care unit (ICU) stay and/or 30-day mortality. Secondary endpoints included mortality.Results
The study was stopped early in a situation of futility for the composite outcome of prolonged ICU stay and/or 30-day mortality that was 79 % (15 patients) in the protein C zymogen group and 67 % (12 patients) in the placebo group (p = 0.40) and for a concomitant safety issue: ICU mortality was 79 % (15 patients) in the protein C zymogen group vs 39 % (7 patients) in the placebo group (p = 0.020), and 30-day mortality was 68 vs 39 % (p = 0.072).Conclusion
Protein C zymogen did not improve clinically relevant outcomes in severe sepsis and septic shock adult patients. Given its high cost and the potential increase in mortality, the use of this drug in adult patients should be discouraged.34.
Alex Proekt Jane Wong Yuriy Zhurov Nataliya Kozlova Klaudiusz R. Weiss Vladimir Brezina 《PLoS Clinical Trials》2008,3(11)
To generate adaptive behavior, the nervous system is coupled to the environment. The coupling constrains the dynamical properties that the nervous system and the environment must have relative to each other if adaptive behavior is to be produced. In previous computational studies, such constraints have been used to evolve controllers or artificial agents to perform a behavioral task in a given environment. Often, however, we already know the controller, the real nervous system, and its dynamics. Here we propose that the constraints can also be used to solve the inverse problem—to predict from the dynamics of the nervous system the environment to which they are adapted, and so reconstruct the production of the adaptive behavior by the entire coupled system. We illustrate how this can be done in the feeding system of the sea slug Aplysia. At the core of this system is a central pattern generator (CPG) that, with dynamics on both fast and slow time scales, integrates incoming sensory stimuli to produce ingestive and egestive motor programs. We run models embodying these CPG dynamics—in effect, autonomous Aplysia agents—in various feeding environments and analyze the performance of the entire system in a realistic feeding task. We find that the dynamics of the system are tuned for optimal performance in a narrow range of environments that correspond well to those that Aplysia encounter in the wild. In these environments, the slow CPG dynamics implement efficient ingestion of edible seaweed strips with minimal sensory information about them. The fast dynamics then implement a switch to a different behavioral mode in which the system ignores the sensory information completely and follows an internal “goal,” emergent from the dynamics, to egest again a strip that proves to be inedible. Key predictions of this reconstruction are confirmed in real feeding animals. 相似文献
35.
Callister LC Getmanenko N Garvrish N Eugenevna MO Vladimirova ZN Lassetter J Turkina N 《MCN. The American journal of maternal child nursing》2007,32(1):18-24
PURPOSE: To gain an understanding of the meaning of childbirth to women living in St. Petersburg, the Russian Federation. STUDY DESIGN AND METHOD: Twenty-four Russian women who had given birth in the past 6 months participated in this phenomenological study and were interviewed and audio-taped about the meaning of childbirth. Data collection and analysis occurred concurrently. RESULTS: The Russian sociocultural context of childbirth was identified in specific themes: (1) adhering to cultural traditions, (2) accessing information, (3) maintaining a healthy lifestyle, (4) articulating the spiritual and emotional meaning of giving birth, and (5) transforming as a mother and a person. Study participants reported reading extensively during pregnancy as well as accessing Web-based information about childbirth. Women chose to give their newborns traditional Slavic names and have their infants christened. CLINICAL IMPLICATIONS: The findings of qualitative studies can be used to guide clinical practice, because they provide rich data about essential life events and reactions associated with them. Women from Russia are emigrating to countries all over the world, and thus, their cultural views of childbirth are essential knowledge for the provision of appropriate nursing care. With dramatic socioeconomic and political changes occurring over the past 15 years, along with major changes in healthcare delivery systems, listening to the voices of Russian childbearing women giving birth is vital information for nurses working in maternal-child health settings. 相似文献
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Atorvastatin lowers portal pressure in cirrhotic rats by inhibition of RhoA/Rho-kinase and activation of endothelial nitric oxide synthase 总被引:4,自引:0,他引:4
Trebicka J Hennenberg M Laleman W Shelest N Biecker E Schepke M Nevens F Sauerbruch T Heller J 《Hepatology (Baltimore, Md.)》2007,46(1):242-253
In cirrhosis, increased RhoA/Rho-kinase signaling and decreased nitric oxide (NO) availability contribute to increased intrahepatic resistance and portal hypertension. Hepatic stellate cells (HSCs) regulate intrahepatic resistance. 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) inhibit synthesis of isoprenoids, which are necessary for membrane translocation and activation of small GTPases like RhoA and Ras. Activated RhoA leads to Rho-kinase activation and NO synthase inhibition. We therefore investigated the effects of atorvastatin in cirrhotic rats and isolated HSCs. Rats with secondary biliary cirrhosis (bile duct ligation, BDL) were treated with atorvastatin (15 mg/kg per day for 7 days) or remained untreated. Hemodynamic parameters were determined in vivo (colored microspheres). Intrahepatic resistance was investigated in in situ perfused livers. Expression and phosphorylation of proteins were analyzed by RT-PCR and immunoblots. Three-dimensional stress-relaxed collagen lattice contractions of HSCs were performed after incubation with atorvastatin. Atorvastatin reduced portal pressure without affecting mean arterial pressure in vivo. This was associated with a reduction in intrahepatic resistance and reduced responsiveness of in situ-perfused cirrhotic livers to methoxamine. Furthermore, atorvastatin reduced the contraction of activated HSCs in a 3-dimensional stress-relaxed collagen lattice. In cirrhotic livers, atorvastatin significantly decreased Rho-kinase activity (moesin phosphorylation) without affecting expression of RhoA, Rho-kinase and Ras. In activated HSCs, atorvastatin inhibited the membrane association of RhoA and Ras. Furthermore, in BDL rats, atorvastatin significantly increased hepatic endothelial nitric oxide synthase (eNOS) mRNA and protein levels, phospho-eNOS, nitrite/nitrate, and the activity of the NO effector protein kinase G (PKG). CONCLUSION: In cirrhotic rats, atorvastatin inhibits hepatic RhoA/Rho-kinase signaling and activates the NO/PKG-pathway. This lowers intrahepatic resistance, resulting in decreased portal pressure. Statins might represent a therapeutic option for portal hypertension in cirrhosis. 相似文献
40.
Bokeriia LA Golukhova EZ Breskina NY Polunina AG Davydov DM Begachev AV Kazanovskaya SN 《Cerebrovascular diseases (Basel, Switzerland)》2007,23(1):50-56
BACKGROUND: The aim of the study was to determine the effects of asymmetric cerebral embolic load on cognitive functions. METHODS: Thirty-six open heart surgery (OH) and 26 coronary artery bypass grafting (CABG) patients were evaluated by neuropsychological and transcranial Doppler tests. RESULTS: OH was associated with a significantly larger microembolic load in comparison to CABG. In OH patients, the microembolic load at the left middle cerebral artery correlated with a verbal memory decline, whereas the microembolic load at the right middle cerebral artery correlated with a nonverbal memory deficit. CABG patients also showed a postoperative verbal memory decline which correlated with cardiopulmonary bypass length but not with microembolic load. CONCLUSION: Massive microembolic load during OH induces specific cognitive impairment in accordance to the brain region to which they are delivered. In atherosclerotic patients, the left temporal region is especially prone to perioperative ischemia. 相似文献