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Dysphoric Rumination Impairs Concentration on Academic Tasks   总被引:3,自引:0,他引:3  
Three studies investigated the effects of dysphoric rumination on concentration during 3 academic tasks—reading a passage from the GRE (Study 1), watching a videotaped lecture (Study 2), and proofreading written text (Study 3). Before performing these tasks, dysphoric and nondysphoric students were induced either to ruminate about themselves or to distract themselves by focusing on neutral images (all three studies) or by planning an event (Study 1). The results supported our hypothesis that dysphoric rumination, relative to distraction, would impair students' concentration. In all 3 studies, dysphoric ruminators reported difficulty concentrating, as well as interfering thoughts, during the relevant academic tasks. Furthermore, dysphoric ruminators were slower than dysphoric distractors in completing the tasks—specifically, reading the GRE passage (Study 1) and answering lecture comprehension questions (Study 2). In addition, dysphoric participants who ruminated showed impaired reading strategies (Study 1), reduced comprehension of academic material (Study 2), and poor proofreading performance (Study 3). These findings suggest that, in addition to its documented adverse effects on mood, thinking, and problem-solving, self-focused rumination interferes with instrumental behavior. Implications for social relationships and job performance are discussed.  相似文献   
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To investigate the molecular mechanism underlying the neuroprotective effect of lithium on cells, in this study, we exposed SH-SY5Y cells to 0.5 mmol/L lithium carbonate(Li2CO2) for 25–50 weeks and then detected the expression levels of some neurobiology related genes and post-translational modifications of stress proteins in SH-SY5Y cells. cDNA arrays showed that pyruvate kinase 2(PKM2) and calmodulin 3(CaM 3) expression levels were significantly down-regulated, phosphatase protein PP2A expression was lightly down-regulated, and casein kinase II(CK2), threonine/tyrosine phosphatase 7(PYST2), and dopamine beta-hydroxylase(DBH) expression levels were significantly up-regulated. Besides, western blot analysis of stress proteins(HSP27, HSP70, GRP78 and GRP94) showed an over-expression of two proteins: a 105 kDa protein which is a hyper-phosphorylated isoform of GRP94, and a 108 kDa protein which is a phosphorylated tetramer of HSP27. These results suggest that the neuroprotective effects of lithium are likely related to gene expressions and post-translational modifications of proteins cited above.  相似文献   
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Background

Elevated IgG4 levels have been reported among patients with primary sclerosing cholangitis. Epidemiological data has only been provided from tertiary centres.

Aims

To investigate the prevalence of elevated IgG4 levels and to compare prognosis between patients with and without elevated IgG4 levels in serum in two European cohorts of patients with primary sclerosing cholangitis.

Methods

Serum IgG4-levels were measured in a consecutive series of patients from Berlin, and retrospectively collected in a population-based cohort from Sweden (total N = 345). Cox's proportional hazard analysis was used to calculate relative risks for liver-related death or liver transplantation and cholangiocarcinoma.

Results

Elevated IgG4 values were demonstrated in 10% of patients. A previous history of pancreatitis, combined intra- and extrahepatic biliary involvement and jaundice were independently associated with elevated IgG4 in multivariate analysis. IgG4 status was not associated with an increased risk for the combined endpoint liver-related death or liver transplantation or cholangiocarcinoma.

Conclusion

The prevalence of elevated IgG4 values among European patients with primary sclerosing cholangitis is similar to what previously has been reported from the United States. Elevated IgG4 was not associated with an increased risk of liver transplantation or liver-related death or cholangiocarcinoma.  相似文献   
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Thermal therapy, Part III: ablation techniques   总被引:2,自引:0,他引:2  
Ablative treatments are gaining increasing attention as an alternative to standard surgical therapies, especially for patients with contraindication or those who refuse open surgery. Thermal ablation is used in clinical applications mainly for treating heart arrhythmias, benign prostate hyperplasia, and nonoperable liver tumors; there is also increasing application to other organ sites, including the kidney, lung, and brain. Potential benefits of thermal ablation include reduced morbidity and mortality in comparison with standard surgical resection and the ability to treat nonsurgical patients. The purpose of this review is to outline and discuss the engineering principles and biological responses by which thermal ablation techniques can provide elevation of temperature in organs within the human body. Because of the individual problems associated with each type of treatment, a wide range of ablation techniques have evolved including cryoablation as well as ultrasound, radiofrequency (RF), microwave, and laser ablation. Aspects of each ablation technique, including mechanisms of action, equipment required, selection of eligible patients, treatment techniques, and patient outcomes are presented, along with a discussion of limitations of the techniques and future research directions.  相似文献   
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Introduction: Simulation is emerging as an essential part of health sciences training programs as it provides safer patient care by reducing the risk of error. In the healthcare environment, simulation continues to spread in emergency specialties, but it is still underdeveloped in ophthalmology and there is a shortage of publications on this subject in Tunisia. Objective: To evaluate the effectiveness of procedural simulation as a teaching tool for funduscopic examination training. Methods and population studied: This was a prospective study including students who underwent procedural simulation training sessions during their ophthalmology internship. The included students were assessed at the initiation and end of each session by a pre-test and post-test. The procedure for performing the funduscopic examination was evaluated by a specific performance score. Student satisfaction was assessed at the end of each session. Results: During the study period, four groups of 12 students were included, for a total of 48 participants spread over 4 simulation sessions. Simulation training improved post-test. assessment scores with an overall median delta of +4.00. It also provided specific skills for performing the funduscopic examination, with an overall median specific performance score of 5.5/8 (5/8 to 7/8). The majority of students were satisfied upon completion of the simulation session. Conclusion: The training of fundus examination using an ophthalmoscopic simulator can improve the skills and knowledge of ophthalmic learners. This type of training can be an innovative addition to traditional learning. methods.  相似文献   
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Pyogenic arthritis of the atlantoaxial joint is scarce. It can lead to several complications, such as spinal cord compression and cerebral vein thrombosis. A 51‐year‐old man presented with a twenty‐day history of inflammatory neck pain. Physical examination revealed paravertebral muscle contracture, restricted neck movement, and fever. Spine magnetic resonance imaging (MRI) showed synovitis of atlanto‐odontoid joint, anterior epidural collection, and cerebral vein thrombosis. Transthoracic echocardiography was unremarkable. The patient was successfully treated with anti‐staphylococcal antibiotic treatment for 12 weeks associated with immobilization of the cervical spine. MRI performed one month after the initiation of the treatment showed disappearance of the epidural collection. The diagnosis of septic arthritis of the atlantoaxial joint should be considered in a patient with inflammatory neck pain. MRI findings are relevant in making the diagnosis of a septic atlanto‐odontoid joint. Conservative treatment, including antibiotic and neck immobilization, can be sufficient for the treatment of pyogenic arthritis of the atlantoaxial joint. Cerebral vein thrombosis is a rare complication due to septic arthritis of the atlantoaxial joint.  相似文献   
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Scorpion envenoming is less studied during gestation; however, it may induce various biological disturbances in maternal organism and hypothetical ones on their fetuses. The scope of this report was to elucidate some biological effects of such poisoning in late pregnant rats. Hence, TBARS levels in maternal lung, placental and fetal pulmonary and hepatic tissues and dam's biochemical blood parameters (glucose, creatinine, 17-β estradiol, progesterone, blood nitrogen urea, sodium and potassium maternal plasma concentrations) had been evaluated after saline (G1), and scorpion venom (G2: 30 min and G3: 60 min) injections in 22nd day pregnant rats. Histological microscopic examination of these tissues was also carried out in HE-stained paraffin sections. In addition, the mean arterial blood pressure following the envenomation variations was measured in three rats from the same pool. Our results showed that Buthus occitanus tunetanus crude venom induced significant increase in maternal, placental and fetal tissues lipid peroxidation, concomitant with blood pressure elevation. Maternal plasma creatinine, estradiol and progesterone concentrations levelled up significantly after 30 min or later (60 min) after the venom injection. Except for a probable pronounced oedema and few congestions in maternal lungs and degenerative aspects of trophoblast cells, all examined tissues showed a conserved structure. These results suggest that scorpion envenomation may induce gestation process disturbances and threatens both mother's and fetus’ well-being.  相似文献   
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