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Spermatogonial stem cell (SSC) transplantation has been shown to restore fertility in several species and may have application for treating some cases of male infertility (e.g., secondary to gonadotoxic therapy for cancer). To ensure safety of this fertility preservation strategy, methods are needed to isolate and enrich SSCs from human testis cell suspensions and also remove malignant contamination. We used flow cytometry to characterize cell surface antigen expression on human testicular cells and leukemic cells (MOLT-4 and TF-1a). We demonstrated via FACS that EpCAM is expressed by human spermatogonia but not MOLT-4 cells. In contrast, HLA-ABC and CD49e marked >95% of MOLT-4 cells but were not expressed on human spermatogonia. A multiparameter sort of MOLT-4–contaminated human testicular cell suspensions was performed to isolate EpCAM+/HLA-ABC/CD49e (putative spermatogonia) and EpCAM/HLA-ABC+/CD49e+ (putative MOLT-4) cell fractions. The EpCAM+/HLA-ABC/CD49e fraction was enriched for spermatogonial colonizing activity and did not form tumors following human-to–nude mouse xenotransplantation. The EpCAM/HLA-ABC+/CD49e+ fraction produced tumors following xenotransplantation. This approach could be generalized with slight modification to also remove contaminating TF-1a leukemia cells. Thus, FACS provides a method to isolate and enrich human spermatogonia and remove malignant contamination by exploiting differences in cell surface antigen expression.  相似文献   
134.
输液中注射用头孢米诺钠的稳定性   总被引:9,自引:0,他引:9  
蒋云根  朱宁江  付庆华  谢文 《医学争鸣》2005,26(11):971-971
1材料和方法 1.1材料日本岛津10-Arp高效液相色谱仪,C18柱(5 μm,4.6 mm×150 mm),PHS-3C型pH计(上海雷磁仪器厂);注射用头孢米诺钠(南昌立健药业有限公司,批号:20040701),50 g/L葡萄糖注射液(四川科伦大制药有限公司,批号:040912-091),100 g/L葡萄糖注射液(湖南科伦大制药有限公司,批号:040710-07),9 g/L氯化钠注射液(湖南科伦大制药有限公司,批号:040926-06),葡萄糖氯化钠注射液(湖南科伦大制药有限公司,批号:040929-06),甲硝唑注射液(安徽双鹤药业有限公司,批号:040926-2E);甲醇、冰醋酸、四氢呋喃均为分析纯.  相似文献   
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Serial allograft biopsies were performed on a renal transplant patient who experienced recurrent episodes of acute cellular rejection as well as cyclosporine nephrotoxicity. Five biopsies were performed after acute elevations of the serum creatinine level (15, 46, 155, 244, and 324 days after transplant). Each specimen was evaluated by routine histologic techniques as well as by immunofluorescence analysis and by monoclonal antibody labeling for determination of the cell phenotype of the mononuclear cell infiltrates within each specimen. The first and third specimens disclosed significant T-cell infiltrates with an equal number of T-cytotoxic-suppressor (Leu 2a) and T-helper-inducer (Leu 3a) cells in a diffuse cortical pattern, while the second biopsy showed a slightly milder infiltrate with a marked elevation (7:1) in the Leu 3a:Leu 2a ratio in the cortical-diffuse pattern. Clinically, the patient responded dramatically to cyclosporine dosage reduction following the second biopsy, and bolus steroid antirejection therapy following the first and third biopsies. These findings suggest that phenotypic cell marker analysis within the context of histologic pattern is a useful adjunct to the routine histologic evaluation of renal allograft biopsy specimens and may provide a means of differentiating rejection from cyclosporine nephrotoxicity.  相似文献   
137.
Baird  DM; Royle  NJ 《Human molecular genetics》1997,6(13):2291-2299
A high level of sequence polymorphism combined with linkage disequilibrium has created a limited number of highly diverged haplotypes across the human Xp/Yp telomere junction region. To gain insight into the unusual genetic characteristics of this region, we have examined the orthologous sequences in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla) and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp sequence is higher (average 2.6-fold) than that observed at other loci. The position of the human Xp/Yp telomere is unique, as additional sequences are present at this location in the other three species. These included an array of subterminal satellite in the chimpanzee and, in the gorilla a small interstitial array of telomere-like repeats followed by sequences with strong homology to the human 18p subterminal region. In the orang-utan, two alleles with different structures were identified. These differ by the presence or absence of a short interspersed nuclear element (SINE) sequence just proximal to long arrays of telomere-like repeat sequences that probably represent the proximal end of the orang-utan Xp/Yp telomere. In addition, a high level of sequence divergence between the two orang-utan structures was identified. This divergence is similar to that observed between the human Xp/Yp telomere-adjacent haplotypes. The high sequence divergence and evidence of gross rearrangements indicate that the Xp/Yp telomeric region has evolved faster than the rest of the genome.   相似文献   
138.
We have studied a group of 349 institutionalized propositi with mental retardation, and found 12 fra(X)-positive cases among 155 males (7.7%) and 8 fra(X)-positive cases among 194 females (4.1%). The males had characteristic manifestations of the Martin-Bell syndrome. Another 7 males, who were initially considered "borderline", having expression of fra(X) less than 4% and a non-characteristic phenotype, were eventually considered negative. Among 5,624 patients (2,764 males and 2,860 females) that were admitted to the Pediatric Department of the University of Catania during the period July 1986 - June 1987, 210 (120 males and 90 females) had mental retardation. Of these, 75 were analyzed for the presence of fra(X) (q27.3); 5 males (0.18% of all males) and 2 females (0.07% of all females) were fra(X)-positive. The males had the Martin Bell syndrome phenotype. The presence of fra(X) (q27) was confirmed in another 4 male propositi that were referred to our outpatient services with a clinical diagnosis of Martin-Bell syndrome.  相似文献   
139.

Background

Concerns about pathology testing such as the value provided by new tests and the potential for inappropriate utilization have led to a greater need to assess costs and benefits. Economic evaluations are a formal method of analyzing costs and benefits, yet for pathology tests, questions remain about the scope and quality of the economic evidence.

Objective

To describe the extent and quality of published evidence provided by economic evaluations of pathology tests from 2010 to 2015.

Methods

Economic evaluations relating to pathology tests from 2010 to 2015 were reviewed. Eight databases were searched for published studies, and details recorded for the country, clinical focus, type of testing, and consideration of sensitivity, specificity, and false test results. The reporting quality of studies was assessed using the Consolidated Health Economic Evaluation Reporting Standards checklist and cost-effectiveness ratios were analyzed for publication bias.

Results

We found 356 economic evaluations of pathology tests, most of which regarded developed countries. The most common economic evaluations were cost-utility analyses and the most common clinical focus was infectious diseases. More than half of the studies considered sensitivity and specificity, but few studies considered the impact of false test results. The average Consolidated Health Economic Evaluation Reporting Standards checklist score was 17 out of 24. Cost-utility ratios were commonly less than $10,000/quality-adjusted life-year or more than $200,000/quality-adjusted life-year.

Conclusions

The number of economic evaluations of pathology tests has increased in recent years, but the rate of increase has plateaued. Furthermore, the quality of studies in the past 5 years was highly variable, and there is some question of publication bias in reporting cost-effectiveness ratios.  相似文献   
140.
Pseudophakic cystoid macular oedema (PCMO) remains a significant cause of compromised postoperative vision in contemporary cataract surgery. Well‐established risk factors include intraoperative complications such as posterior capsule rupture and preoperative factors including: diabetes mellitus, uveitis, retinal vein occlusion, epiretinal membrane. The role of topical glaucoma medications in PCMO continues to be debated. Current treatment strategies largely target suppression of inflammation. Topical NSAIDs remain the mainstay in prophylaxis and treatment of PCMO. Topical corticosteroids are commonly used as monotherapy or in combination with NSAIDs. Unfortunately, high‐quality trials are notably lacking for other PCMO treatment modalities such as: periocular corticosteroids, orbital floor triamcinolone, intravitreal triamcinolone, corticosteroid implants, intravitreal bevacizumab and pars‐plana vitrectomy. A lack of consistency in defining PCMO and resolution of PCMO explains why even large systematic reviews may come to contradictory conclusions. This review explores the varied contemporary evidence‐base in relation to the aetiology, diagnosis, prophylaxis and treatment of PCMO.  相似文献   
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