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91.
Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery pressure post‐LVAD. We report on a series of heart failure patients, and the effect of sildenafil on the incidence of RV failure after LVAD implantation. We retrospectively analyzed the data of end‐stage heart failure patients who underwent LVAD implantation with pulmonary hypertension and RV dysfunction prior to surgery. Patients were divided into two groups; group 1: patients who received sildenafil perioperatively, and group 2: patients who did not receive sildenafil. Hemodynamic and echographic data were collected before and after surgery. Fourteen patients were included, 8 patients in group 1 and 6 in group 2. Sildenafil was administered with a mean dose of 56.2 ± 9.4 mg in group 1 and was able to significantly reduce right heart failure incidence, and to demonstrate a significant reduction in pulmonary vascular resistance, pulmonary artery pressure, transpulmonary gradient, and a significant increase in cardiac output. In conclusion, sildenafil seems to have a promising role perioperatively in preventing acute RV failure postsurgery in patients with RV dysfunction and pulmonary hypertension, requiring LVAD therapy.  相似文献   
92.

Purpose

To compare the clinical, pathological and oncological outcome of EAML with classic angiomyolipoma (AML).

Methods

A retrospective review of patients’ files with a diagnosis of AML was conducted. Both classic and epithelioid AML were compared as regard the patients’ demographics, mode of presentation, tumor features and follow-up data. The accuracy of preoperative radiological diagnosis of EAML and the postoperative pathological data were evaluated.

Results

Between November 1988 and July 2012, 1,502 renal masses were treated. Forty-two patients (2.8 %) had renal AML of whom 12 patients (28.6 %) had epithelioid morphology. All the patients with EAML were symptomatic on presentation compared to 16.7 % asymptomatic patients with classic AML. Specific diagnosis of EAML was not suggested based on preoperative radiological evaluation. In one patient, there was a venous tumor extension into the right renal vein; another patient had a solitary pulmonary nodule. Pathological data of EAML patients showed wide areas of necrosis (4 patients), atypia (6 patients), increased mitotic figures (2 patients), nuclear anaplasia, enlarged nuclei and prominent nucleoli (3 patients), and multilobulated multinucleated giant cells (5 patients). At a median follow-up period of 12 and 9 months for EAML and classic AML groups, respectively, one patient with EAML had evidence of both local recurrence and distant metastasis 3 months following open radical nephrectomy.

Conclusion

Epithelioid AML is potentially aggressive and usually present as a symptomatic renal mass. It may be misdiagnosed as malignant renal mass on preoperative radiological evaluation.  相似文献   
93.
The need for orthodontic treatment is increasing all the time. As the treatment is time consuming ranging from a year to several years, any method of reducing the period of treatment and increasing the quality of the tissue will be beneficial to patients. The use of non-invasive techniques such as low level laser therapy and low intensity pulsed ultasound in accelerating orthodontic tooth movement are promising. Thus, this overview study will help to generate more understanding about the background information and the possible applications of them in daily orthodontics, depending on previous literature searching for reviews and original research articles.  相似文献   
94.
The present study was performed to show the ameliorative effect of berberine (BBR), as an antioxidant and anti‐inflammatory agent, against experimental varicocele (VCL)‐induced molecular and histological damages. For this purpose, 50 mature Wistar rats were divided into control, control‐sham, VCL‐sole, 50 mg/kg and 100 mg/kg BBR‐treated VCL‐induced groups. The tissue levels of interleukin‐6 (IL‐6), tumour necrosis factor‐α (TNF‐α), nitric oxide (NO), total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD) and gluthatione peroxidase (GSH‐px) as well as the mRNA levels of testicular CuZn SOD, MnSOD, EC‐SOD and GSH‐px were evaluated. The serum concentration of testosterone and germ cells mRNA damage were analysed. Finally, the sperm viability, motility, DNA integrity and chromatin condensation were analysed. Observations revealed that, the BBR significantly downregulated VCL‐increased IL‐6, TNF‐α and NO levels, upregulated the CuZn SOD, MnSOD, EC‐SOD and GSH‐px mRNA level, decreased testicular MDA content, enhanced serum testosterone level and ameliorated testicular TAC, SOD and GSH‐px levels. The animals in BBR‐treated groups exhibited diminished mRNA damage versus non‐treated VCL‐induced group. The BBR has significantly (p < 0.05) improved sperm parameters. In conclusion, the BBR by promoting testicular antioxidant potential and by downregulating inflammatory reactions fairly promotes spermatogenesis and upregulates the sperm quality.  相似文献   
95.
Background contextApproximately 25% of vertebroplasty patients experience subsequent fractures within 1 year of treatment, and vertebrae adjacent to the cemented level are up to three times more likely to fracture than those further away. The increased risk of adjacent fractures postaugmentation raises concerns that treatment of osteoporotic compression fractures with vertebroplasty may negatively impact spine biomechanics.PurposeTo quantify the biomechanical effects of vertebroplasty on adjacent intervertebral discs (IVDs) and vertebral bodies (VBs).Study designA biomechanics study was conducted using cadaveric thoracolumbar spinal columns from elderly women (age range, 51–98 years).MethodsFive level motion segments (T11–L3) were assigned to a vertebroplasty treated or untreated control group (n=10/group) such that bone mineral density (BMD), trabecular architecture, and age were similar between groups. Compression fractures were created in the L1 vertebra of all specimens, and polymethylmethacrylate bone cement was injected into the fractured vertebra of vertebroplasty specimens. All spine segments underwent cyclic axial compression for 115,000 cycles. Microcomputed tomography imaging was performed before and after cyclic loading to quantify compression in adjacent VBs and IVDs.ResultsCyclic loading increased strains 3% on average in the vertebroplasty group when compared with controls after 115,000 cycles. This global strain manifested locally as approximately fourfold more compression in the superior VB (T12) and two- to fourfold higher axial and circumferential deformations in the superior IVD (T12–L1) of vertebroplasty-treated specimens when compared with untreated controls. Low BMD and high cement fill were significant factors that explained the increased strain in the vertebroplasty-treated group.ConclusionsThese data indicate that vertebroplasty alters spine biomechanics resulting in increased compression of adjacent VB and IVD in severely osteoporotic women and may be the basis for clinical reports of adjacent fractures after vertebroplasty.  相似文献   
96.

Background

The transosseous-equivalent (TOE) repair of the rotator cuff tears was invented to make up for several shortcomings of the double-row (DR) repair. However, no studies have compared the clinical aspects of the DR repair and the TOE technique, supporting the superior results of the TOE technique over the DR repair, including the benefit of minimizing surgical steps. We asked whether differences existed between the two repairs regarding clinical outcomes, time and costs.

Materials and methods

Subjects included 55 using the DR repair and 119 using the TOE repair for the medium to large sized rotator cuff tears. Clinical outcomes were measured with a Visual Analog Scale, American Shoulder and Elbow Surgeons score, Constant score, and shoulder strength. For practical aspects, operative time and number of suture anchors used for the medial and lateral rows were compared.

Results

Both repairs brought substantial improvements in pain and function. However, significant differences were not detected between the repairs in all the clinical measurements. Regarding operative time and costs, in the medium size tears, a statistical difference was found only in the anchors used for the lateral row. In the large size tears, the DR repair required more operation time than the TOE repair, while the TOE repair used more anchors for the lateral row.

Conclusion

This study failed to demonstrate clinical differences between the techniques. However, when stratifying rotator cuff tears according to the tear sizes, significant differences were found in operative time and cost: the DR repair had the advantage of cost effectiveness by saving anchors for the lateral row, while the TOE repair required less operative time with more anchors used for the lateral row in the large size tears. This finding provides evidence to support the use of the TOE repair to reduce surgical steps.  相似文献   
97.

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   
98.
99.
Immunologic heterogeneity of diffuse large cell lymphoma   总被引:2,自引:0,他引:2  
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.  相似文献   
100.
A case of post-traumatic arachnoiditis ossificans of the cauda equina is reported. The lesion is a rare pathological entity usually confined to the thoracic and high lumbar regions that can cause progressive spinal cord and cauda equine compression. The pathophysiology and therapeutic strategy of this rare entity are still controversial.  相似文献   
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