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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   
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PURPOSE: BMS-214662 is a nonsedating benzodiazepine derivative that exhibits broad spectrum cytotoxicity against human solid tumor cell lines and potently inhibits farnesylation of the H-ras and K-ras oncogenic proteins. This report describes the initial Phase I clinical trial of the compound. The main objective of the study was to determine the dose-limiting toxicities and the maximum tolerated dose of BMS-214662 when administered as a single dose i.v. over 1 h every 21 days to patients with advanced solid tumors. EXPERIMENTAL DESIGN: Patients with advanced solid tumors and adequate organ function were eligible for the study. The dose was escalated according to a modified Fibonacci schedule after evaluating groups of at least three patients for toxicity during the first cycle of therapy at each dose level. Pharmacokinetic and pharmacodynamic studies were performed after administration of the two initial doses. RESULTS: The dose of BMS-214662 was escalated from 36 to 225 mg/m(2) through 5 intermediate dose levels in a total of 44 patients. Dose-limiting toxicities occurred in 3 of the 13 (23%) patients during the first cycle of treatment with 225 mg/m(2), consisting of grade 3 nausea/vomiting in 2 patients and grade 3 diarrhea in another patient. In addition, four of these patients experienced reversible grade 3 transaminitis, which was not considered to be dose-limiting. At the recommended dose for Phase II studies, 200 mg/m(2), the most common side effects were reversible transaminitis, nausea, and vomiting. Although there were no objective responses, one patient with pancreatic cancer continues to receive treatment more than 3.5 years after entering the study. BMS-214662 exhibited linear pharmacokinetics and had a mean biological half-life of 1.55 +/- 0.27 h and a total body clearance of 21.8 +/- 10.8 liters/h/m(2), with a low apparent volume of distribution at steady state (31.5 +/- 12.9 liters/m(2)). In patients treated with the recommended Phase II dose, the mean maximum plasma concentration of the drug was 6.57 +/- 2.94 microg/ml, and farnesyltransferase activity in peripheral blood mononuclear cells decreased to a nadir of 10.5 +/- 6.4% of baseline at the end of the infusion but fully recovered within 24 h. CONCLUSIONS: BMS-214662 can be delivered safely as a single 1-h i.v. infusion at a dose that results in pronounced inhibition of farnesyltransferase activity in peripheral blood mononuclear cells. However, the duration of enzyme inhibition was transient, recovering in parallel with the decline in plasma concentrations of this rapidly eliminated drug. Because indications of anticancer activity were observed in several patients, further optimization of the administration schedule for this promising new compound is warranted.  相似文献   
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This study reports the preliminary results of an outcomes approach to analysis of the effectiveness of endolymphatic sac decompression (ELSD). Using the medical outcomes survey's 36-item, shortform health survey (SF-36), we assessed the quality of life in 33 patients with disabling Meniere's disease undergoing ELSD for medically intractable vertigo. Results indicate that patients with 1995 American Academy of Otolaryngology-Head and Neck Surgery(AAO/HNS) class A or B outcomes showed no significant difference from population norms on the SF-36, whereas patients with AAO/HNS classes C to E outcomes scored significantly below norms. Six patients who were given the SF-36 preoperatively scored consistently below population norms. Postoperatively, they showed a statistically significant improvement and were statistically equal to norms. These findings suggest that the SF-36 is a good measure of the quality of life impairment in patients with disabling Meniere's disease. In addition, SF-36 scores correlated well with the 1995 AAO/HNS classification.  相似文献   
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The transfusion of red blood cells (RBCs), although necessary for treatment of anemia and blood loss, has also been linked to increased morbidity and mortality. RBCs stored for longer durations and transfused in larger volumes are often cited as contributory to adverse outcomes. The potential mechanisms underlying deleterious effects of RBC transfusion are just beginning to be elucidated. In this narrative review, we explore the hypothesis that prolonged RBC storage results in elaboration of substances which may function as danger associated molecular pattern molecules that activate the innate immune system with consequences unfavorable to healthy homeostasis. The nature of these chemical mediators and the biological responses to them offers insight into the mechanisms of these pathological responses. Three major areas of activation of the innate immune apparatus by stored RBCs have been tentatively identified: RBC hemolysis, recipient neutrophil priming, and reactive oxygen species production. The possible mechanisms by which each might perturb the innate immune response are reviewed in a search for potential novel pathways through which transfusion can lead to an altered inflammatory response.  相似文献   
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Abstract

The Forum, for Death Education and Counseling (recently renamed The Association for Death Education and Counseling) celebrated its tenth anniversary in Atlanta, Georgia in April 1986. During its developmental years the Forum has been a significant force in bringing death-related phenomena to the fore and especially through its efforts to improve death education and death-related counseling. Its impact has been felt both nationally and internationally. This article highlights some of the important historical features of the Forum, identifies its early goals and missions, discusses its current status and incipient trends, and offers some suggestions for future development.  相似文献   
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BACKGROUND: Previous studies suggest that intraoperative anesthetic care may influence postoperative pain and recovery from surgery. The authors tested the hypothesis that the addition of intrathecal analgesia to general anesthesia would improve long-term functional status and decrease pain in patients undergoing radical retropubic prostatectomy. METHODS: One hundred patients received either general anesthesia supplemented with intravenous fentanyl or general anesthesia preceded by intrathecal administration of bupivacaine (15 mg), clonidine (75 microg), and morphine (0.2 mg). Patients and providers were masked to treatment assignment. All patients received multimodal pain management postoperatively. Primary outcomes included pain and functional status over the first 12 postoperative weeks. RESULTS: Patients receiving intrathecal analgesia required more intravenous fluids and vasopressors intraoperatively. Pain was well controlled throughout the study (mean numerical pain scores < 3 in both groups at all times studied). Intrathecal analgesia decreased pain and supplemental intravenous morphine use over the first postoperative day but increased the frequency of pruritus. Pain and functional status after discharge from the hospital did not differ between groups. Intrathecal analgesia significantly decreased the duration of hospital stay (from 2.8 +/- 2.0 to 2.1 +/- 0.5 days; P < 0.01) as a result of five patients in the control group who stayed in the hospital more than 3 days. CONCLUSIONS: The benefits of improved immediate analgesia and decreased morphine requirements resulting from intrathecal analgesia must be weighed against factors such as pruritus, increased intraoperative requirement for fluids and vasopressors, and resources needed to implement this modality. Further studies are needed to determine the significance of the decrease in duration of hospital stay.  相似文献   
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PURPOSE: We undertook this study to document the functional natural history of patients undergoing major amputation in an academic vascular surgery and rehabilitation medicine practice. METHODS: A retrospective review was conducted of consecutive patients undergoing major lower extremity amputation and rehabilitation in a university and Department of Veterans Affairs hospital. Main outcome variables included operative mortality, follow-up, survival, median time to incision healing, secondary operative procedures for wound management, and conversion from below-knee amputation (BKA) to above-knee amputation (AKA). For surviving patients, quality of life was determined by degree of ambulation, eg, outdoors, indoors only, or no ambulation; use of a prosthesis; and independence, eg, community housing or nursing facility. RESULTS: From August 1997 through March 2002, 154 patients (130 men; median age, 62 years) underwent 172 major amputations, 78 AKA and 94 BKA, because of either critical limb ischemia (87%) or diabetic neuropathy (13%). Thirty-day operative mortality was 10%. Mean follow-up was 14 months. Healing at 100 and 200 days, as determined with the Kaplan-Meier method, was 55% and 83%, respectively, for BKA, and 76% and 85%, respectively, for AKA. Twenty-three BKA and 16 AKA required additional operative revision, and 18 BKA ultimately were converted to AKA. Survival was 78% at 1 year and 55% at 3 years. Function in surviving patients at 10 and 17 months, respectively, was as follows: 21% and 29% of patients ambulated outdoors, 28% and 25% ambulated indoors only, and 51% and 46% of patients were nonambulatory; 32% and 42% of patients used prosthetic limbs; and 17% and 8% of patients who lived in the community before amputation required care in a nursing facility. CONCLUSIONS: We were surprised to find that vascular patients in a contemporary setting who require major lower extremity amputation and rehabilitation often remain independent despite infrequent prosthesis use and outdoor ambulation. Although any hope for postoperative ambulation in this population requires salvaging the knee joint, because of the morbidity incurred in both wound healing and rehabilitation efforts, aggressive effort should be reserved for selected patients at good risk. Ability to predict ambulation after BKA in the vascular population is poor.  相似文献   
20.
BACKGROUND: Reduced bone mass and fragility fractures are known complications after transplantation in adults. Far less is known about the skeletal effects of transplantation in children and adolescents. METHODS: This cross-sectional study examined the skeletal status of children (ages 9-18 years) who were at least 1 year post-cardiac (n=13), post-renal (n=8), or post-bone marrow (BMT; n=15) transplantation. Bone mass at total hip, femoral neck, spine (L2-4), and whole body (WB) was determined by dual energy x-ray absorptiometry and compared with age, sex, and ethnic-specific reference data. Standard deviations (z-scores) were calculated for both areal bone mineral density (BMD) and estimated volumetric bone density (bone mineral apparent density [BMAD]). RESULTS: Cardiac transplant patients had significantly lower BMD z-scores compared with the reference population at all skeletal sites. BMT recipients had significantly reduced BMD z-scores at total hip, spine, and WB. Kidney transplant patients had a significantly reduced WB BMD z-score only. Spine BMAD z-scores remained significantly reduced in cardiac and BMT subjects. Three of 36 patients had radiographic evidence of spinal fracture after transplantation. No correlation between steroid dosage and any measure of bone mass was observed. CONCLUSIONS: Cardiac and BMT recipients had reduced BMD at multiple skeletal sites, and renal transplant recipients had reduced WB BMD for age. Deficits in spine bone density persisted after correcting for small bone size using BMAD. Low bone density and the occurrence of vertebral fractures indicate that cardiac, renal, and bone marrow transplantation in children is associated with reduced bone health.  相似文献   
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