首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   469篇
  免费   57篇
  国内免费   4篇
耳鼻咽喉   2篇
儿科学   3篇
基础医学   46篇
口腔科学   1篇
临床医学   25篇
内科学   70篇
神经病学   262篇
特种医学   26篇
外科学   3篇
综合类   24篇
预防医学   12篇
眼科学   13篇
药学   36篇
中国医学   4篇
肿瘤学   3篇
  2024年   2篇
  2023年   3篇
  2022年   18篇
  2021年   36篇
  2020年   24篇
  2019年   18篇
  2018年   25篇
  2017年   21篇
  2016年   22篇
  2015年   23篇
  2014年   34篇
  2013年   35篇
  2012年   28篇
  2011年   21篇
  2010年   22篇
  2009年   16篇
  2008年   23篇
  2007年   19篇
  2006年   12篇
  2005年   10篇
  2004年   12篇
  2003年   6篇
  2002年   4篇
  2001年   8篇
  2000年   7篇
  1999年   3篇
  1998年   2篇
  1997年   8篇
  1996年   6篇
  1995年   2篇
  1994年   1篇
  1993年   4篇
  1992年   4篇
  1991年   3篇
  1990年   1篇
  1989年   8篇
  1988年   7篇
  1987年   2篇
  1985年   3篇
  1984年   7篇
  1983年   4篇
  1982年   5篇
  1980年   2篇
  1977年   1篇
  1976年   2篇
  1973年   1篇
  1972年   2篇
  1970年   1篇
  1969年   1篇
  1968年   1篇
排序方式: 共有530条查询结果,搜索用时 15 毫秒
1.
Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals.  相似文献   
2.
The autonomic nervous control of cardiac function during active orthostatic load has been studied by measuring the power spectrum of heart rate fluctuations in 16 insulin-dependent diabetic patients and 14 age-matched control subjects. The patients were subdivided into two groups: 8 with normal respiratory sinus dysrhythmia (RSA+) and 8 with reduced respiratory sinus dysrhythmia (RSA-). In RSA- patients the total power (0.01-0.50 Hz) was significantly reduced compared with control subjects (4.7 versus 15.5 min-2, 2p less than 0.05) and the pattern of heart rate fluctuations was characterized by a relative increase in the low-frequency component (0.01-0.05 Hz) as compared with RSA+ patients and control subjects (45% versus 24% and 27%, both 2p less than 0.01). There was also a significant reduction in the high-frequency component (0.15-0.50 Hz) as compared with RSA+ patients and control subjects (17% versus 36% and 33%, both 2p less than 0.05). During standing, a significant increase in total power was found only in control subjects (2p less than 0.01) and the difference between control subjects, and RSA+ and RSA- patients reached significance (32.2 versus 15.1 and 12.7 min-2, 2p less than 0.02 and 2p less than 0.01). The pattern of heart rate fluctuations in RSA- patients showed no significant change on standing. These results suggest that the reduced overall heart rate variability in diabetic patients with cardiac autonomic neuropathy is associated with a typical heart rate fluctuation pattern.  相似文献   
3.
Summary Spontaneous circadian variations of prostate specific antigen (PSA) and prostatic acid phosphatase (PAP), determined simultaneously by radioimmunoassay (RIA), were investigated by multiple sampling, over a 24-hour period, in 32 patients with prostatic cancer. In 29/32 patients (91%), the coefficient of variation of 24-hour values, for either marker, was greater than that of the RIA method at the same range of values; stage D patients showed the greatest spontaneous variability. Fluctuations around the mean of 24-hour values ranged from-65% to +85% for PAP, from-72% to +190% for PSA, occurring random and independently for each marker. Variability was about 20% greater for PSA than for PAP. The existence of spontaneous fluctuations should be considered in multiple marker evaluation of prostatic cancer patients.Preliminary results of this study have been presented at the International Symposium on Hormonal Therapy of Prostatic Diseases —Basic and Clinical Aspects, April 6–8, 1987, Milan, Italy  相似文献   
4.
Patient on-off diaries are used in clinical trials, but a method to assure agreement between patient and examiner has never been developed. We tested whether a patient-teaching tape increased the rate of agreement between patient diary ratings and simultaneous neurologic assessment by a trained professional. A total of 32 consecutive patients who had Parkinson's disease with motor fluctuations independently completed a 4-h on-off diary (nine ratings) at the same time as an examiner. Those with <80% agreement with the examiner (n = 20) were randomized to view either a training tape that showed motor fluctuations (experimental group) or another videotape of general patient educational material (control group). All patients then underwent the same 4-h assessment of motor fluctuations. To test for long-term retention, they returned 1 month later and, without reviewing the videotape, underwent a final 4-h correlation assessment. After the training tape, the experimental group showed significant improvement, whereas the control group showed no improvement. Furthermore, another month later, the improvement in the experimental group was retained. Based on these findings, we suggest that future clinical trials assessing motor fluctuations incorporate this tape into their basic methodology.  相似文献   
5.
To test the possibility that theophylline induced circadian disappearance of food intake might depend upon rhythmic disruption of blood glucose, insulin and free fatty acids (FFA), theophylline was administered chronically. This markedly lengthened postprandial intermeal intervals during the dark, and induced approximately identical intermeal intervals and identical meal sizes in the light and dark periods. In contrast to the clear light-dark dependent oscillations of serum glucose, insulin and FFA in the controls, the theophyllinized rats lost circadian fluctuation of each of these three chemical substances. Further, theophyllinized rats, unlike controls, had no time-dependent fluctuation in the levels of these substances at ? 120, ?60 or ?15 min preceding the onset of the first meal before the dark. These findings, together with previous reports, explain the disappearance of nocturnal feeding rhythm in theophyllinized rats in terms of functional destruction of circadian regulation in the hypothalamus which modulate the production of chemical determinants of food intake.  相似文献   
6.
Summary Twenty-nine patients with advanced Parkinson's disease were treated with subcutaneous lisuride infusion in addition to a basic therapy consisting of levodopa + PDI in all, and deprenyl in some patients. At the time of the report, 13 patients are still receiving lisuride infusion after 5–36 months, while 16 have dropped out after 0.5–30 months one because of psychosis, three because of insufficient efficacy, three due to death unrelated to treatment, three because of difficulties in handling the pump as outpatients, and six for other reasons. Off-periods and parkinsonian disability in off and in on were reduced significantly. These improvements remained constant throughout the observation period. Once the optimal dose regimen is established, only minor adjustments of the doses of lisuride and levodopa are required in the individual case.  相似文献   
7.
fMRI studies of brain activity at rest study slow (<0.1 Hz) intrinsic fluctuations in the blood‐oxygenation‐level‐dependent (BOLD) signal that are observed in a temporal scale of several minutes. The origin of these fluctuations is not clear but has previously been associated with slow changes in rhythmic neuronal activity resulting from changes in cortical excitability or neuronal synchronization. In this work, we show that individual spontaneous BOLD events occur during rest, in addition to slow fluctuations. Individual spontaneous BOLD events were identified by deconvolving the hemodynamic impulse response function for each time point in the fMRI time series, thus requiring no information on timing or a‐priori spatial information of events. The patterns of activation detected were related to the motor, visual, default‐mode, and dorsal attention networks. The correspondence between spontaneous events and slow fluctuations in these networks was assessed using a sliding window, seed‐correlation analysis, where seed regions were selected based on the individual spontaneous event BOLD activity maps. We showed that the correlation varied considerably over time, peaking at the time of spontaneous events in these networks. By regressing spontaneous events out of the fMRI signal, we showed that both the correlation strength and the power in spectral frequencies <0.1 Hz decreased, indicating that spontaneous activation events contribute to low‐frequency fluctuations observed in resting state networks with fMRI. This work provides new insights into the origin of signals detected in fMRI studies of functional connectivity. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
8.
Background: Dopamine replacement therapies (levodopa, dopamine receptor agonists, anticholinergics, monoamine oxidase B inhibitors, and catechol-O-methyltransferase inhibitors) remain the cornerstones of therapeutic interventions for Parkinson's disease (PD). Despite the treatment options for PD symptoms, a cure remains elusive. An optimal treatment would be one that combined relief in both motor and nonmotor symptoms with neuroprotective properties. Safinamide is an investigational drug for PD currently in development as add-on therapy to both dopamine agonists and levodopa. Safinamide is a unique molecule with a novel mode of action, targeting both dopaminergic and glutaminergic systems, and potentially provides motor symptom control. Preliminary results from experimental models suggest potential neuroprotective effects. Studies on the potential effects on nonmotor symptoms are ongoing. Objective: To review the mechanism of action and pharmacokinetics, and to evaluate the available clinical safety and efficacy results of safinamide. Methods: A search of the electronic database MEDLINE (PubMed, no time limits) was performed on 14 December 2007. The full text of all citations was obtained for review. Furthermore, two abstracts on safinamide published as proceedings of a European conference were reviewed. Results/conclusion: Safinamide is a promising investigational drug for PD with a novel mode of action. Early reports confirm the potential efficacy of safinamide in PD. Further studies on potential effects on cognition and neuroprotection are needed.  相似文献   
9.
10.
目的 探讨收缩压波动对房颤伴高血压患者预后的预测意义 方法 选取2012-2014年于新疆维吾尔自治区人民医院确诊为心房颤动伴高血压的患者,随访其收缩压的变化及平均收缩压,并监测其心源性死亡、急性冠脉综合征、慢性心力衰竭、脑栓塞及外周血管栓塞的发生率。结果在随访的过程中,随着收缩压波动幅度的增加,其终点事件发生率也在不断的增加,收缩压波动最大的四分位组主要终点事件及次要终点事件的发生率是要明显高于收缩压波动最小的四分位组,且患者随诊次数越多,收缩压波动对房颤患者预后的预测意义就越大,这种预测意义在平均收缩压较高的患者中更为明显。结论 收缩压波动可影响房颤伴高血压患者的预后,且收缩压波动越大,房颤患者的预后越不佳。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号