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971.
Abstract The natural history of changes in attachment level in the primary dentition should be determined before considering diagnostic criteria for periodontal diseases in children. The present study was designed to describe longitudinal changes in the distance between the alveolar bone crest and the cementoenamel junction (ABC-CEJ) determined radiographically. Bite-wing radiographs were obtained from 33 children as part of a routine annual dental examination in a rural community. The ABC-CEJ distance of 1500 sites located at the mesial and distal aspects of primary molars and distal aspect of primary cuspids were measured. An analysis of variance model was used to assess the effect of age, sex, tooth, side of the mouth, jaw, site and patient on the ABC-CEJ measurements. The side of the mouth (left, right) and the site (mesial, distal) had no significant effect on the ABC-CEJ distance. ABC-CEJ distances in the upper jaw were greater than in the lower jaw, and different teeth exhibited different ABC-CEJ distances. Canines had the greatest distance and second molars the smallest. The most interesting relationship was between alveolar bone height and age. The overall ABC-CEJ distance seemed to increase with age; however, this was not a linear relationship but followed the pattern of facial growth, with two spurts separated by a period of minimal increase. The results indicate that different levels of ABC-CEJ distance might be considered as a cut-off value for radiographic diagnosis of alveolar bone loss at different ages, for different primary teeth and for different jaws.  相似文献   
972.
The purpose of this paper was to describe our experience with the endovascular management of splenic artery pseudoaneurysms (SAPA). Seven patients with documented SAPA on CT and/or angiography were considered for endovascular treatment. The pseudoaneurysms were located in the main splenic artery (n = 4) or its branches (n = 3). In one patient in whom the pseudoaneurysm was located in a hilar branch, selective catheterization of splenic artery failed. Metallic coils (n = 1), gelfoam and hydrogel particles (n = 1), metallic coils and gelfoam (n = 2), metallic coil, gelfoam and acrylic glue (n = 2) were used as embolization material in the remaining six patients. These patients were followed for a mean period of 11.3 months. Transcatheter embolization was successful in five patients with no procedure‐related complications. In one patient, embolization was incomplete and the patient underwent surgery, but died on the 10th postoperative day because of irreversible shock. Another patient, after successful embolization, underwent surgery for management of an associated pseudocyst. Endovascular treatment is a safe and effective method of management of SAPA.  相似文献   
973.
A bstract Despite many advances in blood conservation techniques, a significant proportion of patients undergoing primary coronary revascularization still require homologous transfusions. Based on a large clinical experience with high-risk patients during coronary artery bypass, a comprehensive strategy to diminish perioperative blood loss was developed by integrating many individual components. An integral component in this strategy is the use of lower heparinization (activated clotting time [ACT] > 280 sec) in conjunction with "tip-to-tip" heparin-bonded cardiopulmonary bypass (CPB) circuits (HBC). This technique was prospectively applied to a group of Jehovah's Witnesses (JW) patients who refuse blood transfusion on religious grounds (n = 9). Outcome was compared to a matched group of patients treated with full heparinization (ACT > 480 sec) used with conventional, nonheparin-bonded CPB circuits (NHBC) performed within the same academic year (n = 455). There were no complications in JW patients who had a significantly lower mediastinal and pleural tube output in the first 24 hours (323 67 mL vs 984 616 mL, p < 0.01). In comparison to JW patients who received no transfusions, 68.1% of patients treated with NHBC were transfused (p 0.0001). In summary, HBC in conjunction with lower anticoagulation was effectively and safely applied to JW patients undergoing coronary artery bypass grafting. This technique should be considered for broader clinical use.  相似文献   
974.
SUMMARY An 80-year-old woman developed an ulcerated, moderately differentiated squamous cell carcinoma (SCC) on the lower leg. Despite local excision and radiotherapy, the patient presented 6 years later with multiple lung metastases which were histologically indistinguishable from the original skin tumour. There was no evidence of metastases to lymph nodes or other viscera.  相似文献   
975.
Summary Changes in vertebral trabecular bone were quantified in female Wistar rats. This study utilized single photon absorptiometry for the measurement of bone mineral content (BMC), quantitative computed tomography (QCT) for the measurement of bone mineral density (BMD), and image analysis histomorphometry for the measurement of trabecular bone volume (TBV). The above measurements were accompanied by biochemical assays of protein and calcium concentrations in the tissues. Also, the activity of bone alkaline and acid phosphatases was measured. Lumbar vertebrae (L4, L5) in old rats 27 months old, compared with those of young rats 7 months old, showed significant decreases in BMC, BMD, TBV, protein and calcium, and enzyme activity. A high degree of correlation was recorded between the above changes. The various changes were accompanied by a marked reduction in the overall wet weight of the vertebrae. Hence, new noninvasive methods to quantitate bone mass can be appliedin vivo to small laboratory animals such as the rat. These methods are much more accurate than standard radiographs in quantitating bone loss and are, therefore, recommended for experimental longitudinal studies related to aging of the skeleton. This study was presented in part at the 2nd International Congress of Biomedical Gerontology, Hamburg, Federal Republic of Germany, July 1987, and at the 5th Annual Meeting of the Japanese Society for Bone and Mineral Research, Tokyo, Japan, August 1987.  相似文献   
976.
Cyclosporin is poorly tolerated in patients with amyloidosisdue to familial mediterranean fever who are receiving colchicine.There is a high incidence of gastro-intestinal side-effectsand muscle weakness, both of which are reversible on stoppingcyclosporin. Thus in patients with amyloidosis secondary tofamilial mediterranean fever treated with colchicine, the useof cyclosporin as an immunosuppressive agent may be restricted.  相似文献   
977.
A study was performed to determine the success of a conservative cavity preparation using the principle of sealing for prevention rather than cavity extension for prevention. A total of 332 restorations were placed in 240 teeth of 110 subjects, aged 6 to 14, with a mean age of 8 years. After 4 years, 205 restorations were examined. Caries appeared in 13 teeth and sealant wear occurred in 14 restorations. Complete sealant loss was observed in eight restorations and partial loss in 38, leaving 156 restorations with complete retention of the sealant. These preliminary results show that conservative cavity preparation with sealing for prevention is a successful technique that conserves valuable tooth structure.  相似文献   
978.
Gruss  HJ; Dower  SK 《Blood》1995,85(12):3378-3404
The TNF receptor superfamily members are all type I membrane glycoproteins with typical homology in the extracellular domain of variable numbers of cysteine-rich repeats (overall homologies, 25% to 30%). In contrast, the TNF ligand superfamily members (with the exception of LT alpha) are type II membrane glycoproteins with homology to TNF in the extracellular domain (overall homologies, 20%). TNF and LT alpha are trimeric proteins and are composed of beta-strands forming a beta-jellyroll. The homology of the beta-strand regions for the TNF ligand superfamily members suggest a similar beta-sandwich structure and possible trimeric or multimeric complex formation for most or all members. A genetic linkage, as evidence for evolutionary relatedness, is found by chromosomal cluster of TNFR p80, CD30, 4-1BB, and OX40 for 1p36; TNFR p60, TNFR-RP, and CD27 for 12p13; TNF, LT alpha, and LT beta for 6 (MHC locus); CD27L and 4-1BBL for 19p13; and FASL and OX40L for 1q25. Of the TNF ligand superfamily, TNF, LT alpha, and LT beta and their receptors (TNFR p60, TNFR p80, and TNFR-RP) interact in a complex fashion of cross-binding. However, the other family members presently have a one ligand/one receptor binding principle (CD27/CD27L, CD30/CD30L, CD40/CD40L, 4-1BB/4-1BBL, OX40/gp34, and FAS/FASL). In general, the members of the TNF ligand superfamily mediate interaction between different hematopoietic cells, such as T cell/B cell, T cell/monocyte, and T cell/T cell. Signals can be transduced not only through the receptors but also through at least some of the ligands. The transduced signals can be stimulatory or inhibitory depending on the target cell or the activation state. Taken together, TNF superfamily ligands show for the immune response an involvement in the induction of cytokine secretion and the upregulation of adhesion molecules, activation antigens, and costimulatory proteins, all known to amplify stimulatory and regulatory signals. On the other hand, differences in the distribution, kinetics of induction, and requirements for induction support a defined role for each of the ligands for T-cell-mediated immune responses. The shedding of members of the TNF receptor superfamily could limit the signals mediated by the corresponding ligands as a functional regulatory mechanism. Induction of cytotoxic cell death, observed for TNF, LT alpha, CD30L, CD95L, and 4-1BBL, is another common functional feature of this cytokine family. Further studies have to identify unique versus redundant biologic and physiologic functions for each of the TNF superfamily ligands.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
979.
A comprehensive systematic preventive dental health program was implemented in a young population with Down's Syndrome during a 30-month period. Twenty children (nine boys and 11 girls), ages 8–13 (mean age, 11), participated in the study, which took place in three hostel-like apartments. The main goals of this program were to achieve good plaque control and subsequently prevent periodontal disease as well as to apply fissure sealants and fluorides in an attempt to prevent dental caries. The mean plaque and gingival indices as well as the percentage of bleeding sites decreased significantly (p < 0.01) following the administration of our oral health program. Caries experience, as indicated by DMFS, decreased from 1.35 to 1.05 surfaces per child, and the use of fissure sealants to prevent occlusal caries was proved to be 100% effective. It is concluded that if the children's efforts are integrated with those of a motivated dentist, dental hygienist, and staff, a well-planned preventive dental health program can lead to a high degree of success in the prevention of dental diseases in young populations with Down's Syndrome .  相似文献   
980.
Stenoses in dialysis fistulas: treatment with percutaneous angioplasty   总被引:1,自引:0,他引:1  
Percutaneous transluminal angioplasty (PTA) was performed on 30 stenotic lesions in 25 dialysis access fistulas. The fistulas were in 23 patients with a mean age of 53 years. Lesions were detected with angiography within a few days after poor flow or increased venous pressure was documented during dialysis. Twenty-two lesions were in patients with polytetrafluoroethylene graft fistulas, five were in patients with bovine carotid fistulas, and three were in patients with endogenous arteriovenous fistulas. There were 28 venous stenoses (20 at the anastomotic site and eight more proximally) and two arterial stenoses. The overall success rate was 80%, with a 6-month patency of 76% and a mean patency after PTA of 9.4 months. Among the venous lesions, the success was 100% for proximal lesions and 71% for anastomotic lesions. There were two technical failures, which required surgery for revision of the fistulas, and four self-limited hematomas. PTA is a safe and effective treatment for stenoses in dialysis fistulas, particularly for lesions remote from the anastomotic sites.  相似文献   
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