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61.
手术显微镜下行上颌窦自然口扩大术治疗33例慢性上颌窦炎患者,报告其手术方法及疗效,并与同期行传统上颌窦根治术(柯陆二氏手术)的疗效进行比较,结果表明该手术疗效明显优于柯陆二氏手术。  相似文献   
62.
本研究旨在观察幽门螺杆菌(HP)在非溃疡性消化不良(NUD)发病中的作用。结果显示,NUD患者HP阳性率为83.6%,HP感染率显著高于健康人(P<0.01)。提示幽门螺杆菌在非溃疡性消化不良发病机制中可能有重要意义。  相似文献   
63.
BACKGROUND: Oxytocin is known to reduce anxiety and stress in social interactions as well as to modulate approach behavior. Recent studies suggest that the amygdala might be the primary neuronal basis for these effects. METHODS: In a functional magnetic resonance imaging study using a double-blind, placebo-controlled within-subject design, we measured neural responses to fearful, angry, and happy facial expressions after intranasal application of 24 IU oxytocin compared with placebo. RESULTS: Oxytocin reduced right-sided amygdala responses to all three face categories even when the emotional content of the presented face was not evaluated explicitly. Exploratory whole brain analysis revealed modulatory effects in prefrontal and temporal areas as well as in the brainstem. CONCLUSIONS: Results suggest a modulatory role of oxytocin on amygdala responses to facial expressions irrespective of their valence. Reduction of amygdala activity to positive and negative stimuli might reflect reduced uncertainty about the predictive value of a social stimulus and thereby facilitates social approach behavior.  相似文献   
64.
AIMS: Caffeine enhances counterregulatory responses to acute hypoglycaemia. Our aim was to explore its effects on cortical function, which are not known at present. METHODS: Regional brain activation during performance of the four-choice reaction time (4CRT) at different levels of complexity was measured using functional magnetic resonance imaging (fMRI) at euglycaemia (5 mmol/l) and hypoglycaemia (2.6 mmol/l) in the presence and absence of caffeine in six healthy right-handed men. RESULTS: During hypoglycaemia, caffeine enhanced adrenaline responses to hypoglycaemia (2.5 +/- 0.7 nmol/l to 4.0 +/- 1.0 nmol/l, P = 0.01) and restored the brain activation response to the non-cued 4CRT, the linear increases in regional brain activation associated with increased task complexity and the ability to respond to a cue that were lost in hypoglycaemia alone. CONCLUSIONS: Caffeine can sustain regional brain activation patterns lost in acute hypoglycaemia, with some restoration of cortical function and enhanced adrenaline responsiveness. A methodology has been established that may help in the development of therapies to protect against severe hypoglycaemia in insulin therapy for patients with diabetes and problematic hypoglycaemia.  相似文献   
65.
The differential diagnoses of persistent nonproductive cough include numerous pulmonary and nonpulmonary organic disorders as well as functional illnesses. Many diseases can cause cough, and several studies have shown asthma among the most common etiologies associated with chronic cough in adult nonsmokers, as well as children. Psychogenic cough and its relationship to asthma and other asthma-like illnesses is complex since distinct maladies with similar features may coexist individually or in combination in any given patient. While chronic cough may occur as a sole presenting manifestation of bronchial asthma in all age groups, recent findings suggest that most children with persistent cough without other respiratory symptoms do not have asthma. Since several organic, as well as functional diseases, may present with persistent cough as their sole manifestation in either adults or children, cough should not be used as a single or major determinant to diagnose and treat asthma, especially when empirically focused therapy trials fail. Given the range of illnesses causing cough, no single management guideline can be expected to be universally effective.  相似文献   
66.
We performed a prospective study to analyze the functional results following elective laparoscopic sigmoidectomy for computed tomography (CT)-proven diagnosis of acute diverticulitis and review the literature. Forty-three of 45 available patients (96%) who had laparoscopic sigmoidectomy for CT-proven acute diverticulitis answered, after a mean time of 40 months, a questionnaire exploring new abdominal symptoms, bowel function, and the patient’s own judgement of the surgical outcome. Surgical technique aimed at removing all the sigmoid by taking down the splenic flexure and do a colorectal anastomosis. Four patients (9%) complained of new abdominal pain. Bowel function was reported as better for 24 patients (56%), unchanged for 16 patients (37%), and worse for 3 (7%). Twenty patients (47%) considered their final result as excellent to good, 17 patients (40%) as satisfying, and 6 patients (13%) as mediocre. Male gender, absence of preoperative history compatible with an irritable bowel syndrome, length of resected sigmoid and residual acute inflammation on histology are statistically predictive of a better postoperative degree of satisfaction. After elective laparoscopic sigmoidectomy for CT-proven diverticulitis, a great majority of patients are very satisfied with their postoperative general comfort.  相似文献   
67.
Although the concept of receiving MR signal using multiple coils simultaneously has been known for over two decades, the technique has only recently become clinically available as a result of the development of several effective parallel imaging reconstruction algorithms. Despite the success of these algorithms, it remains a challenge in many applications to rapidly and reliably reconstruct an image from partially-acquired general non-Cartesian k-space data. Such applications include, for example, three-dimensional (3D) imaging, functional MRI (fMRI), perfusion-weighted imaging, and diffusion tensor imaging (DTI), in which a large number of images have to be reconstructed. In this work, a systematic k-space-based reconstruction algorithm based on k-space sparse matrices (kSPA) is introduced. This algorithm formulates the image reconstruction problem as a system of sparse linear equations in k-space. The inversion of this system of equations is achieved by computing a sparse approximate inverse matrix. The algorithm is demonstrated using both simulated and in vivo data, and the resulting image quality is comparable to that of the iterative sensitivity encoding (SENSE) algorithm. The kSPA algorithm is noniterative and the computed sparse approximate inverse can be applied repetitively to reconstruct all subsequent images. This algorithm, therefore, is particularly suitable for the aforementioned applications.  相似文献   
68.
69.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。  相似文献   
70.
The Barthel Index (BI), the Modified Barthel Index (MBI) and the Functional Independence Measure (FIM) are all widely used by occupational therapists as assessment tools for clinical decision-making and outcome measurement. All of these tools have demonstrated validity and the BI and the FIM have demonstrated inter-rater reliability. The MBI has been modified to increase sensitivity; however, there have been no publications on the inter-rater reliability of this tool following the changes. The purpose of this research was to examine the inter-rater reliability of two versions of the Barthel Index, and draw some comparisons between this assessment tool and the FIM. Twenty-five patients with neurological and orthopaedic conditions were assessed by three occupational therapists using the three tools. The method of analysis selected was percentage agreement and intraclass correlation coefficient. The results indicated that both the original and modified versions of the Barthel Index possess good inter-rater reliability. As all three tools have demonstrated adequate reliability and validity, it is suggested that clinicians select the most sensitive tool that best meets their clinical needs, and use this assessment tool in its standardized format.  相似文献   
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