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71.
72.

Objective

Fluid balance is important in patients undergoing hemodialysis. “Dry” weight is usually estimated clinically, and also, bioimpedance is considered reliable. Ultrasonography of inferior vena cava (IVC) estimates central venous pressure, and lung ultrasound evaluates extravascular (counting B-lines artifact) lung water. Our study was aimed to clarify their usefulness in the assessment of volume status during hemodialysis.

Methods

A total of 71 consecutive patients undergoing hemodialysis underwent lung and IVC ultrasound and bioimpedance spectroscopy immediately before and after dialysis.

Results

There was a significant reduction in the number of B-lines (3.13 vs 1.41) and in IVC diameters (end-expiratory diameter 1.71 vs 1.37; end-inspiratory diameter 1.19 vs 0.95) during dialysis. The reduction in B-lines correlated with weight reduction during dialysis (p 0.007); none of the parameters concerning the IVC correlated with fluid removal. At the end of the dialysis session, the total number of B-lines correlated with bioimpedance residual weight (p 0.002).

Discussion

The reduction in B-lines correlated with fluid loss due to hemodialysis, despite the small pre-dialysis number, confirming that lung ultrasound can identify even modest variations in extravascular lung water. IVC ultrasound, which reflects the intravascular filling grade, might not be sensitive enough to detect rapid volume decrease. Clinically estimated dry weight had a poor correlation with both bioimpedance and ultrasound techniques. Post-dialysis B-lines number correlates with residual weight assessed with bioimpedance, suggesting a role for ultrasound in managing hemodialysis patients.  相似文献   
73.
74.
Skeletal injuries requiring bone augmentation techniques are increasing in the context of avoiding or treating difficult cases with bone defects, bone healing problems, and bone regeneration limitations. Musculoskeletal severe trauma, osteoporosis-related fractures, and conditions where bone defect, bone collapse or insufficient bone regeneration occur are prone to disability and serious complications. Bone cell therapy has emerged as a promising technique to augment and promote bone regeneration. Interest in the orthopaedic community is considerable, although many aspects related to the research of this technique in specific indications may be insufficiently recognised by many orthopaedic surgeons. Clinical trials are the ultimate research in real patients that may confirm or refute the value of this new therapy. However, before launching the required trials in bone cell therapy towards bone regeneration, preclinical data is needed with the cell product to be implanted in patients to ensure safety and efficacy. These preclinical studies support the end-points that need to be evaluated in clinical trials. Orthopaedic surgeons are the ultimate players that, through their research, would confirm in clinical trials the benefit of bone cell therapies. To further foster this research, the pathway to eventually obtain authorisation from the National Competent Authorities and Research Ethics Committees under the European regulation is reviewed, and the experience of the REBORNE European project offers information and important clues about the current Voluntary Harmonization Procedure and other opportunities that need to be considered by surgeons and researchers on the topic.  相似文献   
75.

Introduction

Teeth are often included in the radiation field during head and neck radiotherapy, and recent clinical evidence suggests that dental pulp is negatively affected by the direct effects of radiation, leading to impaired sensitivity of the dental pulp. Therefore, this study aimed to investigate the direct effects of radiation on the microvasculature, innervation, and extracellular matrix of the dental pulp of patients who have undergone head and neck radiotherapy.

Methods

Twenty-three samples of dental pulp from patients who finished head and neck radiotherapy were analyzed. Samples were histologically processed and stained with hematoxylin-eosin for morphologic evaluation of the microvasculature, innervation, and extracellular matrix. Subsequently, immunohistochemical analysis of proteins related to vascularization (CD34 and smooth muscle actin), innervation (S-100, NCAM/CD56, and neurofilament), and extracellular matrix (vimentin) of the dental pulp was performed.

Results

The morphologic study identified preservation of the microvasculature, nerve bundles, and components of the extracellular matrix in all studied samples. The immunohistochemical analysis confirmed the morphologic findings and showed a normal pattern of expression for the studied proteins in all samples.

Conclusions

Direct effects of radiotherapy are not able to generate morphologic changes in the microvasculature, innervation, and extracellular matrix components of the dental pulp in head and neck cancer patients.  相似文献   
76.

Objective

Considering the high incidence of Temporomandibular Disorders (TMD) in the population aged 15-30 years and the fact that students are exposed to stressful psychosocial factors, the purposes of this study were: to verify clinical symptoms and jaw functionality in college students with TMD according to the anxiety/depression (A/D) level and to evaluate the correlation between A/D and functionality, maximum mouth opening (MMO) and pain and muscle activity.

Material and Methods

Nineteen students with TMD diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders underwent two assessments during an academic semester. The evaluations were based on questionnaires (MFIQ - Mandibular Function Impairment Questionnaire; HADS - Hospital Anxiety and Depression Scale), clinical measurements (MMO without pain, MMO and assisted MMO; palpation of joint and masticatory muscles), and electromyography. The HADS scores obtained in the two assessments were used to classify all data as either "high" or "low" A/D. Data normality, differences and correlations were tested with the Shapiro-Wilk test, Student''s t-test (or the Wilcoxon test), and Spearman test, respectively. The alpha level was set at 0.05.

Results

None of the clinical variables were significantly different when comparing low and high A/D data. In low A/D there was a significant correlation between HADS score and: MFIQ (P=0.005, r=0.61), and MMO without pain (P=0.01, r=-0.55).

Conclusions

Variation in A/D level did not change clinical symptoms or jaw functionality in college students with TMD. Apparently, there is a correlation between TMJ functionality and A/D level, which should be further investigated, taking into account the source of the TMD and including subjects with greater functional limitation.  相似文献   
77.

Background

Characterized as a sudden and temporary loss of consciousness and postural tone, with quick and spontaneous recovery, syncope is caused by an acute reduction of systemic arterial pressure and, therefore, of cerebral blood flow. Unsatisfactory results with the use of drugs allowed the nonpharmacological treatment of neurocardiogenic syncope was contemplated as the first therapeutic option.

Objectives

To compare, in patients with neurocardiogenic syncope, the impact of a moderate intensity aerobic physical training (AFT) and a control intervention on the positivity of head-up tilting test (HUT) and orthostatic tolerance time.

Methods

Were studied 21 patients with a history of recurrent neurocardiogenic syncope and HUT. The patients were randomized into: trained group (TG), n = 11, and control group (CG), n = 10. The TG was submitted to 12 weeks of AFT supervised, in cycle ergometer, and the CG to a control procedure that consisted in 15 minutes of stretching and 15 minutes of light walk.

Results

The TG had a positive effect to physical training, with a significant increase in peak oxygen consumption. The CG did not show any statistically significant change before and after the intervention. After the intervention period, 72.7% of the TG sample had negative results to the HUT, not having syncope in the revaluation.

Conclusion

The program of supervised aerobic physical training for 12 weeks was able to reduce the number of positive HUT, as it was able to increase tolerance time in orthostatic position during the HUT after the intervention period.  相似文献   
78.
79.

Background

Bartter patients may be hypercalciuric. Additional abnormalities in the metabolism of calcium, phosphate, and calciotropic hormones have occasionally been reported.

Methods

The metabolism of calcium, phosphate, and calciotropic hormones was investigated in 15 patients with Bartter syndrome and 15 healthy subjects.

Results

Compared to the controls, Bartter patients had significantly reduced plasma phosphate {mean [interquartile range]:1.29 [1.16–1.46] vs. 1.61 [1.54–1.67] mmol/L} and maximal tubular phosphate reabsorption (1.16 [1.00–1.35] vs. 1.41 [1.37–1.47] mmol/L) and significantly increased parathyroid hormone (PTH) level (6.1 [4.5–7.7] vs. 2.8 [2.2–4.4] pmol/L). However, patients and controls did not differ in blood calcium, 25-hydroxyvitamin D, alkaline phosphatase, and osteocalcin levels. In patients, an inverse correlation (P?P?P?Conclusions The results of this study demonstrate a tendency towards renal phosphate wasting and elevated circulating PTH levels in Bartter patients.  相似文献   
80.

Background

The aim of this report is to describe the effect of daily hemodialysis on the growth of children with end-stage renal disease (ESRD).

Methods

We performed a prospective, observational study on 24 children with ESRD undergoing daily hemodialysis (DHD). The control group comprised 26 children on concurrent conventional hemodialysis (CHD), and the follow-up for both groups was 9.3?±?3.0 months. No patient received growth hormone (GH) therapy.

Results

At the onset of the study, the height-for-age Z-score was ?2.12?±?1.54 in the CHD group and ?2.84?±?2.27 in the DHD group (p?=?0.313). Assuming an increase of 0.5 standard deviation scores (SDS) of the height-for-age parameter as an improvement of growth, there were 33 % of patients in the DHD group and 8 % in the CHD group (p?=?0.035). The cumulative probability of gain in height for age at 12 months was 40 % in the DHD group versus 15 % in the CHD group (p?=?0.047). Also, 98 % of patients in the DHD group had an adequate total caloric intake, whereas 38 % in the CHD group reached this goal (p?<?0.001). No patient left the study due to intensification of the dialysis modality.

Conclusions

Our data show that the DHD favored a 0.5 SDS height gain in a third of patients without GH treatment. Dialysis intensification was not a cause for treatment dropouts, and DHD should be considered as a treatment for selected cases, especially small children.  相似文献   
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