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761.
We report a patient with Legionella pneumophila pneumonia after infliximab therapy for rheumatoid arthritis. Arguments are discussed for an emerging incidence of infections with intracellular microorganisms, granulomatous and non-granulomatous, in patients having received anti-TNFalpha therapy. These discussions consist of clinical and epidemiological data, experimental data in animals, theoretical evidence, and we provide a possible pathogenetic mechanism.  相似文献   
762.
763.
We recently described a sensitive and specific assay that detects the fusion of HIV-1 virions to a broad range of target cells, including primary CD4 cells. This assay involves the use of virions containing beta-lactamase-Vpr (BlaM-Vpr) and the loading of target cells with CCF2, a fluorogenic substrate of beta-lactamase. Since Vpr strongly associates with the viral core, uncoating of the viral particle might be required for effective cleavage of CCF2 by BlaM-Vpr. Here, we show that BlaM-Vpr within mature viral cores effectively cleaves CCF2, indicating that this assay measures virion fusion independently of uncoating. We also show that wildtype and Nef-deficient HIV-1 virions fuse with equivalent efficiency to HeLa-CD4 cells, SupT1 T cells, and primary CD4 T cells. Since Nef enhances cytoplasmic delivery of viral cores and increases viral infectivity, these findings indicate that Nef enhances an early post-fusion event in the multistep process of viral entry. Possible sites of Nef action include enlargement of the fusion pore, enhanced uncoating of viral particles, and more efficient passage of viral cores through the dense cortical actin network located immediately beneath the plasma membrane.  相似文献   
764.
BACKGROUND: We investigated the impact of treatment with long-acting, injectable risperidone versus placebo on health-related quality of life (HRQoL) in patients with schizophrenia. Results are discussed in the context of HRQoL in the general U.S. population. METHOD: Patients with DSM-IV schizophrenia entered a randomized, double-blind, placebo-controlled trial. After screening, previous antipsychotics were discontinued, and oral risperidone was titrated up to a dose of 4 mg/day over 1 week. Patients were then randomly assigned to receive placebo [N = 92] or long-acting risperidone (25 [N = 93], 50 [N = 97], or 75 mg [N = 87] every 2 weeks) for 12 weeks. HRQoL was measured using the Medical Outcomes Study Short-Form 36-item questionnaire (SF-36). RESULTS: At week 12, patients receiving long-acting risperidone had improved significantly (p <.05) in 5 domains of the SF-36 (bodily pain, general health, social functioning, role-emotional, and mental health) compared with patients receiving placebo. The effect was greatest for the 25-mg group, with significant improvement versus placebo in 6 domains (p <.05). At baseline, all SF-36 domain scores except bodily pain were significantly lower (p <.05) than normal values in all groups. With placebo, scores in all 8 domains remained below normal values after 12 weeks, while patients receiving long-acting risperidone showed improvement in HRQoL toward normal levels, with clinically meaningful improvements in all mental-health domains. In the 25-mg group, scores in 7 domains were not statistically different from normal values after 12 weeks. CONCLUSIONS: Long-acting, injectable risperidone improved HRQoL toward normal levels. After 12 weeks, HRQoL of patients receiving 25 mg was not significantly different from normal.  相似文献   
765.
OBJECTIVE: This study determined the long-term safety and effectiveness of risperidone in treating severe disruptive behavior in children with subaverage intelligence. METHOD: This 48-week, open-label extension included 107 children ages 5-12 years with severe disruptive behavior disorders (according to DSM-IV criteria and a score of > or = 24 on the conduct problem subscale of the Nisonger Child Behavior Rating Form) and subaverage intelligence (IQ 36-84) who completed at least 2 weeks of a randomized, double-blind, placebo-controlled study of risperidone. All patients received 0.02-0.06 mg/kg/day of oral risperidone; the purpose was to accumulate long-term safety data. Scores on the Nisonger Child Behavior Rating Form were also obtained. RESULTS: The mean risperidone dose was 1.5 mg/day. The most common adverse events reported were somnolence (33%), headache (33%), rhinitis (28%), and weight gain (21%). Somnolence was usually mild and transient. The mean weight increase was 5.5 kg; half was attributable to developmentally expected growth. Transient and asymptomatic increases in prolactin levels were observed. There were no significant changes in Extrapyramidal Symptom Rating Scale scores and no cases of tardive dyskinesia. No clinically relevant changes in ECGs or vital signs were noted. Risperidone was associated with rapid, significant improvement on the conduct problem subscale score of the Nisonger Child Behavior Rating Form in patients previously treated with placebo; improvement was maintained during long-term treatment and in patients previously given risperidone. CONCLUSIONS: Long-term risperidone appears to be generally safe, well tolerated, and effective for treating severely disruptive behaviors in children with subaverage intelligence.  相似文献   
766.
This report describes the introduction of case-based learning into the final-year dental programme at the Dublin Dental School. Students attended a series of one-hour sessions in groups of 8. Each group appointed a chairman for each session and a tutor facilitated the discussion. Case details were provided during the session with relevant diagnostic records. At weekly discussion sessions, the group findings and treatment options were considered. The diagnosis and treatment plans were then discussed by clinicians involved in the treatment of the case. Following the last session, the case-based learning programme was evaluated by means of a questionnaire distributed to both tutors and students. Both students and tutors rated the sessions positively. Case-based learning was found to be a worthwhile progression from problem-based learning.  相似文献   
767.
BACKGROUND: Migraine headache is common and has multiple etiologies. A number of mitochondrial anomalies have been described for migraine, and mitochondrial dysfunction has been implicated as one potential pathophysiological mechanism. Carnitine is used by mitochondria for fatty acid transportation; its deficiency, however, has not been implicated in migraine pathophysiology. METHODS AND RESULTS: Two adolescent girls presented to the Headache Center at Cincinnati Children's Hospital Medical Center with frequent headaches and were diagnosed with migraine by the International Headache Society (IHS) criteria. Both girls had a history of recurrent fatigue, muscle cramps, and multiple side effects from their prophylactic treatment. Carnitine levels were measured and found to be low. Carnitine supplementation was initiated. Both patients had a reduction in headache frequency, as well as an improvement in their associated symptoms and other complaints. A skin and muscle biopsy obtained from one patient revealed a partial carnitine palmityltransferase II deficiency in the muscle only. CONCLUSIONS: Carnitine palmityltransferase II deficiency may represent another etiology for migraine headache, and may be useful in further defining the pathophysiology of migraine. When properly recognized, supplementation with carnitine may improve the outcome of the migraine as well as the carnitine-associated symptoms.  相似文献   
768.
769.
Oxidative stress is involved in the pathogenesis of atherosclerosis, and angiotensin II (AT-II) induces oxidative stress and enhances atherogenesis. Aldosterone, which has an important role in the pathology of heart failure, has recently been implicated as a mediator of AT-II biologic activities. In this study, we analyzed whether administration of the selective aldosterone blocker eplerenone to atherosclerotic apolipoprotein E-deficient (E0) mice would affect their oxidative status and atherogenesis. Apolipoprotein E-deficient mice were administered chow containing eplerenone (200 mg/kg/day) for 3 months. Blood pressure, serum and macrophage oxidative status, and aortic atherosclerotic lesion area were evaluated in mice treated with eplerenone compared with untreated mice. Eplerenone administration significantly decreased systolic and diastolic blood pressure by 12% and 11%, respectively, compared with untreated mice. Serum susceptibility to lipid peroxidation decreased by as much as 26%, and serum paraoxonase activity increased by 28% in eplerenone-treated mice compared with untreated mice. Peritoneal macrophages from eplerenone-treated mice contained reduced levels of lipid peroxides, and their macrophage oxidation of low-density lipoprotein (LDL) and superoxide ion release were significantly reduced (by 17% and 43%, respectively), compared to untreated mice. Daily injections of AT-II (0.1 mL, 10(-)7M) during the final 3 weeks of the study in eplerenone-treated mice substantially attenuated the eplerenone-mediated reduction in macrophage superoxide release and LDL oxidation. Finally, the atherosclerotic lesion area in aortas of eplerenone-treated mice was significantly reduced (by 35%) versus untreated mice, and this effect was reversed by AT-II. Administration of the selective aldosterone blocker eplerenone significantly reduced oxidative stress and atherosclerosis progression in E0 mice. These data suggest that aldosterone could have a significant pro-oxidative role in the pathogenesis of atherosclerosis.  相似文献   
770.
The induction or exacerbation of autoimmune diseases is a potential adverse effect of immunostimulating drugs. Vaccines have been suspected of such actions. Epidemiological studies, however, have so far failed to demonstrate any causal relationship between vaccination and autoimmune diseases, including insulin-dependent diabetes mellitus (IDDM). In this study, autoimmune diabetes-prone non-obese diabetic (NOD) mice were treated with two multivalent diphtheria, tetanus, pertussis, poliomyelitis and haemophilus vaccines (diphtheria, tetanus, acellular pertussis, inactivated polio (DTaP-IVP) or DTaP-IVP/Haemophilus influenza type b (Hib)) intraperitoneally at each of 10, 12 and 14 weeks of age. Although non-statistically significant, the incidence of autoimmune diabetes was slightly reduced by the DTaP-IVP vaccine. Blood glucose levels were actually significantly reduced in the mice treated with the DTaP-IVP vaccine relative to the untreated control mice. A slight decrease in blood glucose levels amongst the mice given the DTaP-IVP/Hib vaccine was also noted. Therefore this study does not support previous claims that children's vaccination might be associated with acceleration or exacerbation of IDDM.  相似文献   
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