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41.
BackgroundWilms tumor (WT) affects Black children disproportionately. Genetic aberrations within WT specimens that contribute to this disparity have not been reported.MethodsThe Therapeutically Applied Research to Generate Effective Treatments (TARGET) database was queried for WT patient and genomic features. Clinical and genetic variables were compared by race.ResultsWithin the discovery set (enriched for adverse events; N = 94 White, 19 Black, 14 Other/unreported patients), Black children were more likely to present with advanced stage disease (p = 0.019). Within the validation set (primarily a random sampling of NWTS-5; N = 360 White, 92 Black, 72 Other/Unreported), Black children appeared older at diagnosis (p = 0.050), had decreased median follow-up time (p<0.0005) and were over-represented (17.4%) relative to the concurrent U.S. Census (12.8%). Among the 37 target genes sequenced, ACTB (p = 0.030) and DICER1 (p = 0.026) mutations were more common in Black patient specimens, whereas DGCR8 (p = 0.041) mutations were more common in White patient specimens. White patient specimens were more likely to contain one or multiple targeted mutations (p = 0.026).ConclusionWithin the TARGET database, Black children were over-represented and harbored WT specimens containing more frequent ACTB and DICER1 mutations. In contrast, WT from White children contained overall more mutations in targeted genes and specifically in DGCR8.Level of EvidenceIII.  相似文献   
42.
Summary The purpose of this study was to determine whether bone mineral density (BMD) measurements at the lumbar spine and femoral neck provided comparable information to women planning to use that knowledge to help them make a decision about hormone replacement therapy. Eighty-eight healthy Caucasian women, aged 44–59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lumbar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiometry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as at risk for osteoporosis, bone density more than one standard deviation (SD) below the young adult mean, or as low risk, bone density at or above this level. The re that 46 women would be classified into the low risk category on the basis of spinal BMD alone. However, 28 of these 46 women would fall into the at risk category when the femoral neck BMD was measured. Sixty-one percent of women informed they were at low risk on the basis of spinal BMD would be considered at risk based on femoral neck BMD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD were added. These results suggest that both lumbar spine and proximal femur measurements should be made when women are using bone density measurements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years.  相似文献   
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Background: Regional lymph node tumor volumes in patients undergoing sentinel lymph node (SN) biopsy (SNB) for treatment of cutaneous melanoma have not been described. The objectives of this study were to describe the lymph node tumor volumes typically seen in this population and to correlate tumor volumes with tumor thickness and positive SN characteristics.Methods: Review of a consecutive series of patients with clinically localized cutaneous melanoma who underwent SNB of nonpalpable regional lymph node basins followed by complete lymphadenectomy (LND) was performed. Multiple lymph node sections from positive SNs and nonsentinel nodes (NSNs) in LND specimens were examined microscopically. Individual tumor deposit diameters were measured using an ocular micrometer. Aggregate tumor volumes were calculated for SN and LND specimens. Tumor volumes and SN and LND positivity rates were correlated with tumor thickness, the number of positive SNs, and the presence of multiple SN tumor deposits.Results: SNB procedures were performed for 149 melanomas in 189 regional nodal basins. The mean tumor depth was 2.48 mm. The mean number of SNs/basin was 2.1. Thirty-two of 149 SNB procedures (21.5%) revealed a total of 34 nodal basins with at least one positive SN. The median tumor volume in positive SNs was 4.7 mm3 (range, 0.1-3618 mm3; mean, 209 mm3). The median aggregate tumor volume in positive LND specimens was 4.9 mm3 (range, 0.1-3618 mm3; mean, 224 mm3). Six basins (17.6%) contained at least one positive NSN. The regional node aggregate tumor volume correlated weakly with tumor thickness (Pearsons correlation coefficient = .302, P = .0934). NSN positivity was not predicted by tumor thickness, American Joint Committee on Cancer tumor stage, number of positive SNs, or number of metastatic deposits within SNs.Conclusions: Most melanoma-positive SNs contain minute tumor volumes. Tumor thickness and patterns of SN metastases may not be predictive of tumor burden or the presence of positive NSNs.  相似文献   
44.
Background: Three cases of heparin-induced thrombocytopenia (HIT) were observed in patients undergoing isolated limb perfusion (ILP) with melphalan. This occurrence prompted the discontinuation of prophylactic postoperative heparin in ILP patients and its avoidance in patients undergoing isolated hepatic perfusion (IHP). The need to reassess these decisions led to a review of thrombocytopenia in both patient populations.Methods: Records of all patients treated with ILP or IHP at our institution from July 1992 through November 1996, were reviewed. Nine IHP patients were tested prospectively for heparinrelated antibodies using serum samples obtained perioperatively and during the second postoperative week.Results: Thrombocytopenia (<100,000 platelets/L) developed postoperatively in 30% of 131 ILP patients and in 77% of 56 IHP patients. No cases of HIT were identified other than the three who had been previously diagnosed. The prevalence of HIT in heparinized ILP patients was 2.8% (3/108). All nine IHP patients developed heparin-related antibodies postoperatively.Conclusions: Because the prevalence of HIT following ILP is in the range observed in other clinical settings, postoperative heparin prophylaxis is an option. However, it probably should be limited to the first week, and daily platelet counts should be reviewed for a pattern of thrombocytopenia consistent with HIT. The prevalence of heparin-related antibodies after IHP is so high that prophylactic heparin should be avoided in this setting.  相似文献   
45.
Summary Cyclophosphamide demonstrates enhanced tumoricidal activity with decreased bone marrow toxicity when given on a divided-dose schedule in certain animal models. A total of 22 patients presenting with refractory metastatic cancer were treated in a phase I trial of continuous infusion of cyclophosphamide over 96 h. Granulocytopenia of <500/l that lasted for > 14 days or thrombocytopenia of <25,000/l that lasted for > 14 days was the target dose-limiting toxicity in the absence of nonhematologic grade 4 toxicity. The maximal tolerated dose was 7 g/m2. Three patients died. Of 21 evaluable patients, 9 responded, including 8/9 who had experienced disease progression during prior oxazaphosphorine-containing combination chemotherapy. Clinically meaningful responses were observed in patients who had demonstrated clinical resistance to an oxazaphosphorine drug given at lower doses.Supported in part by U.S. Public Health Service grant P01CA-38493 and by a grant from the Mather's Foundation. Two of the authors (J. P. E. and A. D. E.) are recipients of Career Development awards from the American Cancer Society, and one (T. C. S.) is a recipient of a Faculty Development Award from the Pharmaceutical Manufacturer's Association Foundation  相似文献   
46.
Mattern  M.R.; Paone  R.F.; Day  R.S.  III 《Carcinogenesis》1981,2(11):1215-1218
Upon treatment with N-methyl-N'-nitro-N-nitroso-guanidine (MNNG),human cell strains characterized as either proficient or defectiveboth in repair of alkyla-tion-damaged DNA and in supportingthe growth of MNNG-treated adenovirus (Mer+ and Mer pheno-types(1,2), all underwent a rapid relaxation of nucleokl DNA, asjudged by sedimentation in 15–30% neutral sucrose gradients.DNA in the repair-proficient Mer+ strains (normal fibroblastand tumor) was restored to the rapidly-sedimenting (control)form within 2–4 h after the removal of MNNG. In contrast,nucleoid DNA of the repair-deficient Mer tumor strainsremained slowly-sedimenting even after 48 h of incubation. Thedelayed recovery of Mer nucleoid DNA was specific forMNNG damage, since after u.v. irradiation, to which Mer+ andMer strains are equally resistant (2), all cell linestested underwent DNA relaxation within the first hour afterirradiation (3 J/m2) and regenerated rapidly-sedimenting nucleoidswithin 4–6 h of repair incubation.  相似文献   
47.
Permanent low-activity iodine-125 implants for cerebral metastases   总被引:1,自引:0,他引:1  
Beginning in 1987, selected patients with metastatic braintumors were treated with permanent implants of low-activityradioactive iodine-125 (125I) seeds. These patients underwent craniotomy,gross total resection of the metastatic lesion, andplacement of the seeds. In general, criteria fortreatment included the presence of a recurrent tumorwith a volume too large to permit radiosurgery,and a Karnofsky Performance Score of 70 orhigher. Thirteen patients underwent 14 implant procedures; allreceived external whole-brain radiotherapy. Implant dose ranged from43 Gy to 132 Gy, with a meanof 83 Gy. Survival after implantation ranged from2 weeks to almost 9 years, with amedian of 9 months. Clinical and radiographic localcontrol was obtained in 9 patients. Two patientsdied of acute, postoperative complications within a monthof implantation, so no information regarding tumor controlis available for them. Late complications included abone flap infection in one patient and aCSF leak in another; both were treated withoutfurther sequelae.These results demonstrate that permanent 125I implants canresult in good survival and quality of life,and occasionally can yield long-term survival. Potentially, itis a cost-effective treatment in that a separateprocedure for stereotactic implantation or radiosurgery is notneeded, as is the case with the useof temporary high-activity seeds. The permanent implantation itselfadds less than 10 minutes to the craniotomy,and the risk of symptomatic radiation necrosis islow. We recommend consideration of this procedure inpatients harboring large, recurrent metastatic tumors that requirefurther surgery.  相似文献   
48.
Purpose: To determine the impact of whole pelvic irradiation on the risk of PSA failure in prostate cancer patients, at high predicted risk for lymph node involvement, receiving definitive radiotherapy.

Materials and Methods: Between October 1987 and December 1995, 506 patients with clinically localized prostate cancer were treated with definitive radiotherapy at UCSF and affiliated institutions. Treatment consisted of 4-field whole pelvic irradiation followed by a prostate-only boost, or prostate-only treatment (median follow-up was 35 months and 30 months, respectively). PSA failure was defined as: 1. a PSA value ≥ 1 ng/ml; or 2. a PSA value that rose ≥ 0.5 ng/ml in ≤ 1 year posttreatment on two consecutive measurements, with the first rise defined as the time of failure. The calculated risk of lymph node positivity (%rLN+) was defined as (iPSA) + 10(GS-6), and high risk was defined as %rLN+ ≥ 15%. Univariate and multivariate analyses were performed.

Results: A total of 201 high-risk patients were identified. High-risk patients who received whole pelvic irradiation had significantly improved freedom from PSA failure compared to those who received prostate-only treatment (median PFS = 34.3 months vs. 21.0 months; p = 0.0001). Potential confounding variables, including initial PSA, Gleason score, T stage, radiation dose, year of treatment, use of three-dimensional (3D) conformal techniques, and use of hormone therapy, did not account for the observed difference in time to PSA failure. Multivariate analysis revealed type of radiation treatment to be the most significant independent predictor of outcome.

Conclusion: Whole pelvic radiotherapy significantly improves the PSA failure-free survival in patients with a high calculated risk of lymph node positivity.  相似文献   

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