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31.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
32.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
33.
OBJECTIVE: To evaluate the effect of interferon-alpha2B on mumps orchitis, often caused by postpubertal mumps and which can result in permanent testicular atrophy. PATIENTS AND METHODS: The study included 21 patients with mumps orchitis, treated between May 1990 and June 1997. Patients were randomly assigned into two groups: in group 1, 13 patients received therapy with interferon-alpha2B (3 x 10(6) IU per day) and group 2 did not, acting as controls. All were evaluated by measurements of testis size, mumps virus titre, hormone level and semen analysis. RESULTS: In group 1, the patients' symptoms resolved within 2-3 days and the volume of the testes returned to normal within 11 days; there was no testicular atrophy in any patient during the follow-up. However, asthenospermia continued to be detected in four patients (unilateral in two, bilateral in two). In group 2, the patients' symptoms resolved within 5-6 days and the volume of the testes returned to normal within 10 days; testes atrophied in three patients (unilateral in two, bilateral in one) during the follow-up. Asthenospermia continued in four patients (unilateral in two, bilateral in two). CONCLUSION: These results suggest that treatment with systemic interferon-alpha2B is effective in preventing testicular atrophy when combined with standard symptomatic treatment.  相似文献   
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Background

The frequency of granular cell tumors (GCTs) identified in the gastrointestinal tract has recently increased with the increased use of routine endoscopy. Endoscopic treatment is increasingly used as an alternative to traditional surgical resection, but there are few reports on the efficacy, safety, and long-term prognosis of endoscopic treatment for GCTs. The aim of this study was to assess the efficacy, safety, and long-term prognosis of endoscopic resection for the gastrointestinal GCTs.

Methods

We examined a total of 27 GCTs in 25 patients who were treated by endoscopic resection from January 2007 to February 2011. For endoscopic resection, endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) was used.

Results

Twenty GCTs were located in the esophagus, 5 in the stomach, and 2 in the colon. The median size of the GCTs was 10 mm; the largest size, located in the ascending colon, measured 18 mm. EMR with a ligation device was performed in 20 cases, conventional EMR in 5 cases, and ESD in 2 cases. En bloc resection was performed in 25 cases (92.6 %), and endoscopic complete resection piecemeal resection was achieved in 25 cases (92.6 %). Pathologic complete resection was achieved in 22 lesions (81.5 %). Intraprocedural bleeding was noted in three patients, with no occurrence of perforation or postprocedure stricture. No recurrence was observed during the mean follow-up period of 15 months (range 9–31 months).

Conclusions

Endoscopic resection appears to be a safe and effective treatment for GCTs in the gastrointestinal tract.  相似文献   
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Objectives

Some of the airway complications relate to the use of cyclosporine (CsA), a potent agent widely used after organ transplantations. Several recent studies have demonstrated CsA treatment to induce reactive oxygen species (ROS). The present study was undertaken to investigate effects of CsA on production of ROS and antoxidant defense of airway cells using the human bronchial epithelial cell line BEAS-2B.

Methods

We measured biological antioxidant potential (BAP), as well as ROS and malondialdehyde levels in BEAS-2B cells after CsA treatment, using Free Radical Analytical System 4 kits (Diacron, Grosseto, Italy). ROS production was expressed as Carr Units as established by the manufacturer and BAP as μmol/2 × 105 cells; malondialdehyde, by the thiobarbituric acid assay.

Results

ROS production was increased in the BEAS-2B cells after CsA treatment: 73.5 at 0 (controls); 82.5 at 10; 84.0 at 30; 86.0 at 50; and 93.0 Carr Unit/2 × 105 cells at 100 μg/mL of CsA. The levels of BAP were 1821 at 0 (controls), 1698 at 10; 1653 at 30; 1366 at 50 μg/mL; and 1391 at 100 μg/mL. The levels of malondialdehyde were increased: 3.8 at 0 (controls); 3.4 at 10; 4.4 at 30; 4.2 at 50: and 5.0 nmol/106 cells at 100 μg/mL.

Conclusions

Increased production of ROS and decreased BAP by CsA in BEAS-2B cells may increase malondialdehyde levels by radical-induced damage.  相似文献   
39.

Background

Rifampin (RFP) is a first-line antituberculosis drug, but it increases the risk of acute rejection (AR) in transplant recipients. This study evaluated whether quinolone (QNL) can replace RFP in renal transplant recipients with tuberculosis.

Methods

One hundred nine patients with active tuberculosis were included. Patients consisted of RFP (n = 91) and QNL (n = 18) groups based on the initial treatment regimen. Patients with RFP-associated adverse effects were subdivided into RFP-maintenance (RFP-M; n = 18) and QNL-conversion (QNL-C; n = 8) groups. Clinical outcomes were compared between groups.

Results

The incidence of AR was higher in the RFP group than in the QNL group (24.2% vs 5.6%). The QNL group showed significantly higher 10-year graft survival rates than the RFP group (88.1% vs 66.5%; P = .022). The QNL-C group showed significantly higher 10-year graft survival rates than the RFP-M group (87.5% vs 27.8%; P = .011). The rate of complete functional recovery after AR was higher in the QNL-C group than in the RFP-M group (50% vs 22.2%).

Conclusions

A QNL-based regimen may be safe and effective for treatment of tuberculosis and may lower the risk of graft failure in renal transplant recipients.  相似文献   
40.
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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