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341.
342.
Study ObjectivesCortical slow oscillations (SOs) and thalamocortical sleep spindles hallmark slow wave sleep and facilitate memory consolidation, both of which are reduced with age. Experiments utilizing auditory closed-loop stimulation to enhance these oscillations showed great potential in young and older subjects. However, the magnitude of responses has yet to be compared between these age groups. We examined the possibility of enhancing SOs and performance on different memory tasks in a healthy middle-aged population using this stimulation and contrast effects to younger adults.MethodsIn a within-subject design, 17 subjects (55.7 ± 1.0 years) received auditory stimulation in synchrony with SO up-states, which was compared to a no-stimulation sham condition. Overnight memory consolidation was assessed for declarative word-pairs and procedural finger-tapping skill. Post-sleep encoding capabilities were tested with a picture recognition task. Electrophysiological effects of stimulation were compared to a previous younger cohort (n = 11, 24.2 ± 0.9 years).ResultsOvernight retention and post-sleep encoding performance of the older cohort revealed no beneficial effect of stimulation, which contrasts with the enhancing effect the same stimulation protocol had in our younger cohort. Auditory stimulation prolonged endogenous SO trains and induced sleep spindles phase-locked to SO up-states in the older population. However, responses were markedly reduced compared to younger subjects. Additionally, the temporal dynamics of stimulation effects on SOs and spindles differed between age groups.ConclusionsOur findings suggest that the susceptibility to auditory stimulation during sleep drastically changes with age and reveal the difficulties of translating a functional protocol from younger to older populations.  相似文献   
343.
Background: Mood and motivational symptoms have been reported in up to 35% and 51%, respectively, of patients with Parkinson's disease (PD). Preliminary evidence indicates that pramipexole may have a positive effect on these symptoms.Objective: This analysis was conducted to evaluate the effects of pramipexole on mood and motivational symptoms in patients with PD.Methods: Data for the meta-analysis were extracted from all randomized, double-blind, placebo-controlled trials of pramipexole in the manufacturer's database that included part I of the Unified Parkinson's Disease Rating Scale (UPDRS) as an outcome measure. Only patients with baseline scores >0 (range, 0–4) on item 3 (mood) and item 4 (motivation) were included. Separate analyses were performed for mood and motivational symptoms. The outcome of interest was improvement in scores, with no improvement including both unchanged and increased scores. Odds ratios (ORs), 95% CIs, and Cochran-Mantel-Haenszel tests were calculated to compare rates of improvement and no improvement, stratified by trial.Results: Fourteen randomized, double-blind, placebo-controlled trials of pramipexole were identified, all employing the severity of motor symptoms of PD as a primary outcome. Seven of these trials (N = 1296) employed part I of the UPDRS as a secondary outcome measure and were included in the meta-analysis; no other measure of mood or motivational symptoms was used in any of the 14 studies. Six of the 7 studies included patients with motor fluctuations due to levodo-pa treatment, and the remaining study included patients who did not yet require levodopa. Six studies were published in peer-reviewed journals, and all 7 were included in the New Drug Application for pramipexole. The published study reports were usually limited to motor symptoms; only 1 reported on mood and motivation. However, for the purpose of this meta-analysis, the authors had access to data that were not reported in the original publications. In the pooled data set, 480 patients (59.8% male; mean age, 63.3 years) had a baseline score >0 on item 3 (mood). These mood symptoms improved in 64.7% of patients treated with pramipexole and 43.4% of those receiving placebo (OR weighted by trial = 2.41; P < 0.001). Five hundred seventy patients (64.9% male; mean age, 64.1 years) had a baseline score >0 on item 4 (motivation). These motivational symptoms improved in 63.2% of patients treated with pramipexole and 45.0% of those receiving placebo (OR weighted by trial = 2.06; P < 0.001).Conclusions: This meta-analysis of 7 randomized controlled trials suggests that pramipexole had a beneficial effect on mood and motivational symptoms in PD patients who did not have major depressive disorder. The clinical value of pramipexole in the treatment of depressive and apathetic syndromes requires further investigation.  相似文献   
344.

Purpose  

The anti-anginal efficacy of the selective If inhibitor ivabradine has been demonstrated in controlled clinical trials. However, there is limited information about the safety and efficacy of a combined treatment of ivabradine with beta-blockers, particularly outside of clinical trials in every day practice. This analysis from the REDUCTION study evaluated the safety and efficacy of a combined therapy of beta-blockers and ivabradine in every day practice.  相似文献   
345.
Previous work on vocal emotional processing provided little evidence for involvement of emotional processing areas such as the amygdala or the orbitofrontal cortex (OFC). Here, we sought to specify whether involvement of these areas depends on how relevant vocal expressions are for the individual. To this end, we assessed participants' social orientation--a measure of the interest and concern for other individuals and hence the relevance of social signals. We then presented task-irrelevant syllable sequences that contained rare changes in tone of voice that could be emotional or neutral. Processing differences between emotional and neutral vocal change in the right amygdala and the bilateral OFC were significantly correlated with the social orientation measure. Specifically, higher social orientation scores were associated with enhanced amygdala and OFC activity to emotional as compared to neutral change. Given the presumed role of the amygdala in the detection of emotionally relevant information, our results suggest that social orientation enhances this detection process and the activation of emotional representations mediated by the OFC. Moreover, social orientation may predict listener responses to vocal emotional cues and explain interindividual variability in vocal emotional processing.  相似文献   
346.
Subacromial impingement syndrome is a common cause of shoulder pain. The purpose of this article is to review the clinical presentation, physical examination findings, and differential diagnosis of impingement syndrome. Using an evidence-based approach, we propose an algorithm for the management of subacromial impingement syndrome including indications for nonoperative management, advanced imaging, and operative management.  相似文献   
347.
The aim of this study was to investigate the effect of treatment of experimental ovarian cancers with targeted cytotoxic analogs as single compounds and in combination. Targeted cytotoxic analogs of bombesin (AN-215), somatostatin (AN-238), and luteinizing hormone-releasing hormone (AN-207) consisted of 2-pyrrolinodoxorubicin (AN-201) linked to the respective peptide carrier. AN-238 at 200 nmol/kg significantly inhibited growth of UCI-107, ES-2 and OV-1063 ovarian cancers. AN-215 alone at 200 nmol/kg and its combination with AN-238 at one-half of the dose were also able to inhibit the growth of UCI-107 tumors. A combination of AN-238 with AN-207at 50% of the dose strongly suppressed the proliferation of ES-2 and OV-1063 ovarian tumors. Cytotoxic radical AN-201 was toxic and had no significant effect on tumor growth. In contrast, the toxicity of the conjugated peptide analogs was low. Because ovarian cancers tend to acquire chemoresistance, we used real-time PCR to measure the mRNA expression of multidrug resistance protein 1, multidrug resistance-related protein 1, and breast cancer resistance protein after treatment. Low or no induction of multidrug resistance protein 1, multidrug resistance-related protein, and breast cancer resistance protein occurred after treatment with AN-238, AN-215, and the combination of AN-238 with AN-207 or AN-215. These results demonstrate that a therapy with cytotoxic analogs such as single agents and combinations is effective and nontoxic. Our work suggests that cytotoxic peptide analogs of luteinizing hormone-releasing hormone, somatostatin, and bombesin could be used for the therapy of ovarian cancers, considering the lack of induction of chemoresistance.  相似文献   
348.
Antagonists of growth hormone-releasing hormone (GHRH) are being developed for the treatment of various cancers. In this study, we investigated the effectiveness of treatment with GHRH antagonist JMR-132 alone and in combination with docetaxel chemotherapy in nude mice bearing MX-1 human breast cancers. Specific high-affinity binding sites for GHRH were found on MX-1 tumor membranes using ligand competition assays with (125)I-labeled GHRH antagonist JV-1-42. JMR-132 displaced radiolabeled JV-1-42 with an IC(50) of 0.14 nM, indicating a high affinity of JMR-132 to GHRH receptors. Treatment of nude mice bearing xenografts of MX-1 with JMR-132 at 10 microg per day s.c. for 22 days significantly (P < 0.05) inhibited tumor volume by 62.9% and tumor weight by 47.8%. Docetaxel given twice at a dose of 20 mg/kg i.p. significantly reduced tumor volume and weight by 74.1% and 58.6%, respectively. Combination treatment with JMR-132 (10 microg/day) and docetaxel (20 mg/kg i.p.) led to growth arrest of most tumors as shown by an inhibition of tumor volume and weight by 97.7% and 95.6%, respectively (P < 0.001). Because no vital cancer cells were detected in some of the excised tumors, a total regression of the tumors was achieved in some cases. Treatment with JMR-132 also strongly reduced the concentration of EGF receptors in MX-1 tumors. Our results demonstrate that GHRH antagonists might provide a therapy for breast cancer and could be combined with docetaxel chemotherapy to enhance the efficacy of treatment.  相似文献   
349.
Disclosure of HIV serostatus by HIV-infected individuals is considered a prevention strategy, under the assumption that disclosure will prompt risk reduction practices among sex partners. We examined patients' self-reports regarding disclosure messages they found relevant as part of prevention with positives (PwP) interventions in clinical settings. We conducted 52 in-depth interviews with patients participating in 13 PwP interventions. We found that the opportunity to reflect about living with HIV, explore fears of stigma and rejection, develop communication skills and strategies to disclose, and explore a sense of responsibility influenced patients' intention to disclose and their disclosure practices. PwP interventions need to include a combination of messages about disclosure strategies, stigma, and communication, as well as helping patients frame disclosure as a process that includes situations and interactions to consider post-disclosure. PwP disclosure counseling can help influence a shift in patients' risk towards safer sex practices.  相似文献   
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