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11.
BACKGROUND AND OBJECTIVES: This study compared the surface morphology as well as the biocompatibility of dental root cementum treated with Er:YAG laser irradiation alone and with the laser irradiation followed by chemical and/or mechanical conditioning. STUDY DESIGN/MATERIALS AND METHODS: Healthy cementum plates were randomly assigned to the following control and treatment groups: (1) untreated control (C), (2) Er:YAG laser irradiation (L), (3) laser plus tetracycline HCl (TC) placement (L+TP), (4) laser plus TC burnishing (L+TB), (5) laser plus EDTA gel placement (L+EP), (6) laser plus EDTA gel burnishing (L+EB), (7) laser plus saline solution burnishing (L+SB), and (8) laser plus minocycline-HCl paste placement (L+MP). Specimens were subjected to scanning electron microscopy (SEM), histological observation and attachment assay using periodontal ligament (PDL) fibroblasts. RESULTS: The laser irradiation produced a thin affected layer (5.7 microm thickness) with a superficial microstructure on the cementum surface. The characteristic microstructures of the lased surface were fragile and could be removed by chemical and/or mechanical conditioning treatments. The L+TB group exhibited marked exposure of collagen fibers after removal of the microstructures on the lased surface. The L+EP group presented a peculiar, smooth surface without exposure of collagen fibers and a uniform arrangement of spherical microparticles on the ultra-high magnification of SEM. In cell attachment assay, the L+TB group exhibited the greatest number of attached cells among all the groups, followed by the L+EP, L+SB and control group. The laser alone group exhibited the lowest number of cells. CONCLUSIONS: The characteristic microstructure of the root cementum surface after Er:YAG laser irradiation has a tendency to hinder the early attachment of PDL cells. However, chemical and/or mechanical root conditioning treatment may improve and increase the biocompatibility of the Er:YAG laser-treated root cementum by removing the microstructures of the surface and/or further exposing the collagen fibers.  相似文献   
12.
BACKGROUND: For a better understanding of the early stages of cystic fibrosis (CF), it is of major interest to study respiratory epithelial cells obtained as early as possible. Although bronchoalveolar lavage has been proposed for this purpose, nasal brushing, which is a much less invasive technique, has seldom been used in CF infants. The aim of the present study was to examine in a few infants the feasibility of a nasal brushing technique for studies of airway epithelial functions in very young CF infants. METHODS: In 5 CF (median age 12, range 1-18 months) and 10 control infants (median age 5, range 1-17 months), a nasal brushing was performed by means of a soft sterile cytology brush, after premedication with oral paracetamol (15 mg/kg body weight) and rectal midazolam (0.2 mg/kg body weight). Samples were used for microbiological, cytological and functional studies. RESULTS: The procedure was well tolerated. Number of cells collected was similar in CF and non-CF patients (CF: median 230x10(3), range 42x10(3)-900x10(3); non-CF: median 340x10(3), range 140x10(3)-900x10(3)). Median number of viable cells was 67% (range 31-84%). Freshly obtained samples were successfully used for studies of ciliary beating frequency and cAMP-dependent chloride efflux. In 7 out of 17 cell cultures, confluence was obtained (CF: 2 out of 7; non-CF: 5 out of 10). The feasibility of studying protein release and mRNA expression of IL-8, IL-6 and TNF-alpha, under basal conditions and after stimulation by Pseudomonas aeruginosa, was demonstrated. CONCLUSIONS: By means of a simple nasal brushing technique easily performed and well tolerated, it is feasible, in infants, to harvest respiratory cells in sufficient amounts to study the airway epithelium using a broad range of techniques including cell culture.  相似文献   
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14.

Introduction

Rivaroxaban is the first licensed oral direct inhibitor of factor Xa. Recent studies from the RECORD trials suggest rivaroxaban has superior efficacy compared to enoxaparin in preventing venous thromboembolism (VTE) with no significant increase in the major bleeding risk. Concerns remain regarding the incidence of minor bleeding, consequent delayed wound healing and subsequent risk of infection. The aim of this observational study was to assess the incidence of post-operative complications in patients receiving either rivaroxaban or enoxaparin thromboprophylaxis following elective hip and knee arthroplasty.

Methods

A total of 258 patients undergoing elective total hip or knee arthroplasty within one NHS Trust were included. A total of 202 subjects (mean age, 70.7 years ± 10.0, 43 % men) received a daily dose of 10 mg of oral rivaroxaban and 56 (mean age, 70.9 years ± 9.8, 39 % men) had a daily subcutaneous injection of 40 mg of enoxaparin as thromboprophylaxis. Endpoints included VTE (deep vein thrombosis and pulmonary embolism), haemorrhagic wound complications, hospital re-admission, requirement for blood transfusion, minor and major bleeding and death.

Results

There were no significant differences in the incidence of VTE, requirement for blood transfusion and readmission rate between rivaroxaban and enoxaparin-treated patients. The incidence of minor bleeding (2.0 vs. 0 %) and haemorrhagic wound complications (5.0 vs. 1.8 %) were non-significantly higher in the rivaroxaban-treated group. There were no cases of pulmonary embolism, major bleeding or death in either group.

Conclusion

Our experience with rivaroxaban in elective hip and knee arthroplasty showed no significant difference in the incidence of VTE or major bleeding. There was, however, a tendency to greater risk of minor bleeding and wound complications that were largely haemorrhagic in nature, which may have reached significance in a larger study.  相似文献   
15.

Background

The significance of subclinical vitamin D deficiency in the pathogenesis of fractures in children and adolescents currently remains unclear.

Objective

We aimed to determine the prevalence of vitamin D insufficiency and its effect on bone mineral density (BMD) and bone mineral content (BMC) values in a collective of Swiss Caucasian children with a first episode of appendicular fracture.

Design and methods

One hundred teenagers with a first episode of appendicular fracture [50 upper limb fractures (group 1) and 50 lower limb fractures (group 2)] and 50 healthy controls (group 3) were recruited into a cross-sectional study. The BMC and BMD values were measured by dual-energy X-ray absorptiometry, and serum 25 hydroxyvitamin D [25(OH)D] was assessed by electrochemiluminescence immunoassays.

Results

From the 100 injured teenagers in the study, 12 % had deficient vitamin D levels (<20 ng/mL; <50 nmol/L) and 36 % had insufficient levels (≥20 <30 ng/mL; ≥50 <78 nmol/L), whereas 6 and 34 % of healthy controls were, respectively, vitamin D deficient and insufficient. There were no significant differences for serum 25(OH)D levels, L2–L4 BMD Z-score, and L2–L4 BMC Z-score variables (p = 0.216) between the three groups nor for the calcaneal BMD Z-score variables (p = 0.278) between healthy controls and lower limb fracture victims. Investigations on the influences of serum 25(OH)D on BMD and BMC showed no correlation between serum 25(OH)D and L2–L4 BMD Z-scores (r = −0.15; p = 0.135), whereas low but significant inverse correlations were, surprisingly, detected between serum 25(OH)D and calcaneal BMD Z-scores (r = −0.21; p = 0.034) and between serum 25(OH)D and L2–L4 BMC Z-scores (r = −0.22; p = 0.029).

Conclusions

A significant proportion of Swiss Caucasian teenagers were vitamin D insufficient, independent of limb fracture status, in our study. However, this study failed to show an influence of low vitamin D status on BMD and/or BMC of the lumbar spine and heel.  相似文献   
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17.
One of the most important and lethal effects of animal venoms is nephrotoxicity. In Latin America, severe acute kidney injury has been reported after accidents with poisonous arthropods such as bees, caterpillars of the genus Lonomia, and spiders of the genus Loxosceles. In this article the characteristics of these venoms, their probable mechanisms of renal damage, and the clinical picture of the accidents are reviewed.  相似文献   
18.
Previous studies have shown that an epidermal growth factor‐based formulation (Heberprot‐P) can enhance granulation of high‐grade diabetic foot ulcers (DFU). The aim of this study was to explore the clinical effects of this administration up to complete wound closure. A pilot study in 20 diabetic patients with full‐thickness lower extremity ulcers of more than 4 weeks of evolution was performed. Mean ulcer size was 16·3 ± 21·3 cm2. Intralesional injections of 75 μg of Heberprot‐P three times per week were given up to complete wound healing. Full granulation response was achieved in all 20 patients in 23·6 ± 3·8 days. Complete wound closure was obtained in 17 (85%) cases in 44·3 ± 8·9 days. Amputation was not necessary in any case and only one relapse was notified. The most frequent adverse events were tremors, chills, pain and ardour at site of administration and local infection. The therapeutic scheme of intralesional Heberprot‐P administration up to complete closure can be safe and suitable to improve the therapeutic goal in terms of healing of chronic DFU.  相似文献   
19.
The aim was to estimate the incidence of stress urinary incontinence 3 years after delivery and its correlation to mode of delivery and parity. A longitudinal cohort study was conducted with 120 women at the Antenatal Clinic at the State University of Campinas. There was a significant difference in the incidence of postpartum stress urinary incontinence (SUI) among patients with SUI during pregnancy (p > 0.0001). Women that were asymptomatic during pregnancy and had vaginal delivery developed SUI 2.4 times more frequently than after c-section (19.2% and 8.0%, respectively). The incidence of SUI after delivery dropped significantly in the primiparous (p = 0.0073) and multiparous 2–3 (p < 0.0001), but not in the multiparous with four or more deliveries (66.7% to 60.0%) (p = 0.5637). A significant correlation has been observed between parity and SUI (p = 0.0299). Pregnancy possibly predisposes to SUI 3 years after delivery as well as parity. No significant correlation has been demonstrated between mode of delivery and SUI.  相似文献   
20.
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