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31.
Sediment ingestion has recently been identified as an important exposure route for toxicants in waterfowl. The effects of lead-contaminated sediment from the Coeur d'Alene River Basin (CDARB) in Idaho on posthatching development of Canada geese (Branta canadensis) were examined for 6 wk. Day-old goslings received either untreated control diet, clean sediment (48%) supplemented control diet, or CDARB sediment (3449 microg/g lead) supplemented diets at 12%, 24%, or 48%. The 12% CDARB diet resulted in a geometric mean blood lead concentration of 0.68 ppm (ww), with over 90% depression of red blood cell ALAD activity and over fourfold elevation of free erythrocyte protoporphyrin concentration. The 24% CDARB diet resulted in blood lead of 1.61 ppm with decreased hematocrit, hemoglobin, and plasma protein in addition to the effects just described. The 48% CDARB diet resulted in blood lead of 2.52 ppm with 22% mortality, decreased growth, and elevated plasma lactate dehydrogenase-L (LDH-L) activity. In this group the liver lead concentration was 6.57 ppm (ww), with twofold increases in hepatic lipid peroxidation (thiobarbituric acid-reactive substances, TBARS) and in reduced glutathione concentration; associated effects included elevated glutathione reductase activity but lower protein-bound thiols concentration and glucose-6-phosphate dehydrogenase (G-6-PDH) activity. The kidney lead concentration in this group was 14.93 ppm with subacute renal tubular nephrosis in one of the surviving goslings. Three other geese in this treatment group exhibited calcified areas of marrow, and one of these displayed severe chronic fibrosing pancreatitis. Lead from CDARB sediment accumulated less readily in gosling blood and tissues than reported in ducklings but at given concentrations was generally more toxic to goslings. Many of these effects were similar to those reported in wild geese and mallards within the Coeur d'Alene River Basin.  相似文献   
32.
HYPOTHESIS: A subset of patients with hepatocellular carcinoma (HCC) with a diameter of 10 cm or larger may benefit from hepatic resection. DESIGN: Retrospective study of a multi-institutional database. SETTING: Five major hepatobiliary centers. PATIENTS: We identified 300 patients who underwent hepatic resection for HCC 10 cm or larger. MAIN OUTCOME MEASURES: Clinical and pathologic data were collected, and prognostic factors were evaluated by univariate and multivariate analyses. Patient survival was stratified according to a clinical scoring system and pathologic T classification. RESULTS: The perioperative mortality rate was 5%. At a median follow-up of 32 months, the median survival was 20.3 months, and the 5-year actuarial survival rate was 27%. Four clinical factors-alpha-fetoprotein of 1000 ng/mL or higher, multiple tumor nodules, the presence of major vascular invasion, and the presence of severe fibrosis-were significant predictors of poor survival (all P<.05). Patients were assigned a clinical score according to the following risk factors: 1, no factor; 2, one or two factors; or 3, three or four factors. On the basis of the clinical score, patients could be stratified into only 2 distinct prognostic groups: no factor (score of 1) vs 1 or more factors (score of 2 or 3) (P<.001). In contrast, when patients were stratified according to pathologic T classification, 3 distinct groups were identified: T1 vs T2 vs T3 and T4 combined (P<.001). Fifty-six percent of the patients with a clinical score of 2 and 20% of patients with a clinical score of 3 actually had T1 or T2 disease on pathologic examination. CONCLUSIONS: Patients with large HCCs should be considered for liver resection as this treatment is associated with a 5-year survival rate exceeding 25%. Clinical predictors should not be used to exclude patients from surgical resection because these factors do not reliably predict outcome.  相似文献   
33.
This article is focused on the controversial topic of imaging strategies in pediatric urinary tract infection. A review of the recent literature illustrates the complementary roles of ultrasound, diagnostic radiology and nuclear medicine. The authors stress the key role of ultrasound which has recently been debated. The commonly associated vesicoureteric reflux has to be classified as congenital or secondary due to voiding dysfunction. A series of frequently asked questions are addressed in a second section. The proposed answers are not the product of a consensus but should rather be considered as proposals to enrich the ongoing debate concerning the evaluation of urinary tract infection in children.  相似文献   
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35.
HYPOTHESIS: Resection of the nipple-areolar complex (NAC) for central breast cancers that involve the nipple or areola, with postoperative radiation therapy, adheres to the oncologic principles established for breast conservation surgery of other breast cancers. Good or excellent cosmetic results can be achieved. The rate of ipsilateral breast recurrence will be similar to that seen with peripheral breast cancers. The indications for breast conservation surgery can be safely extended to include patients with breast cancers that involve the NAC. DESIGN: Retrospective medical record review; follow-up patient questionnaire. SETTING: Community teaching hospital. PATIENTS: Fifteen patients, aged 46 to 88 years, whose central breast cancers involved the NAC precluding preservation of the NAC. INTERVENTIONS: Nipple-areolar complex resection, postoperative radiation therapy. MAIN OUTCOME MEASURES: Ipsilateral breast recurrence, survival, cosmesis. RESULTS: Ten patients had subareolar cancers that directly involved the nipple or areola; 5 patients had Paget disease of the nipple. Average tumor size was 1.6 cm (range, 0.2-3.5 cm). With a mean follow-up of 32 months (range, 4-109 months), there has been only 1 recurrence (7%), which was treated successfully by modified radical mastectomy. All 15 patients are alive and free of disease. Cosmetic results are satisfactory to excellent, as judged by both the patients and the surgeons. CONCLUSIONS: Nipple-areolar complex resection for central subareolar cancers that directly involve the NAC, as well as for Paget disease of the nipple, extends the indications for breast conservation in other areas of the breast, and with acceptable cosmesis.  相似文献   
36.
This review article focuses on the frequent association between urinary tract infection and functional bladder sphincter disorders which were distributed by the International Children's Continence Society in two main categories referred to as unstable bladder and dysfunctional voiding. Relevant examinations, including ultrasound, voiding cystourethrography, isotopic studies, and urodynamics, are described as well as their main advantages and drawbacks. Emphasis is put on the associated vesicoureteric reflux which should not be considered the central problem in those children. Reflux is induced by distortion of the ureteric meatus, a consequence of a long-standing high pressure in the bladder. Follow-up and treatment should aim to prevent renal damage and to protect the bladder function.  相似文献   
37.
38.
Prognostic factors in well-differentiated thyroid carcinoma   总被引:4,自引:0,他引:4  
OBJECTIVES: To test the prognostic significance of standard clinicopathologic factors in patients with well-differentiated thyroid carcinoma (WDTC). STUDY DESIGN: A retrospective chart review of the thyroid cancer database at Mount Sinai Hospital (Toronto, Canada 1963-2000) was carried out. METHODS: All patients consecutively treated for WDTC with a follow-up period of at least 5 years were eligible for inclusion. Relevant patient, tumor, treatment, and outcome data were collected. The main outcome measures were recurrence rate, actuarial overall, and disease-specific survival at 20 years. RESULTS: Three hundred and thirty-three patients (F 275, M 58) with a median age of 39.7 (range 9-82.9) years were eligible for inclusion in this study (median follow-up 10.4 years, range 5-34.4 years, minimum 5 years). The recurrence rate was 15.6% (52 /333). The overall and disease-specific survival at 10 years was 97.5% and 98.5%, respectively. Likewise, the overall and disease-specific survival at 20 years was 88.4% and 93.3%, respectively. Clinicopathologic factors significant on multivariate regression for the development of disease recurrence included family history of WDTC, advanced stage, and total thyroidectomy (all P < .05). Similarly, advanced stage on presentation was associated with a worse disease-specific survival on multivariate regression (all P < .05). There was a trend for age 60 or greater to predict disease-specific survival (P = .09). CONCLUSIONS: WDTC is associated with a significant recurrence rate but good disease-specific survival. The most important prognostic factors are family history of WDTC, extent of surgical treatment (i.e., total thyroidectomy), and advanced initial stage of disease, with a trend for age 60 years and older.  相似文献   
39.
BACKGROUND: The goal of the current study was to evaluate the efficacy and toxicity of capecitabine in patients with nonresectable hepatobiliary carcinoma. METHODS: The authors performed a retrospective analysis of all patients with hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), or gallbladder carcinoma (GBC) who were ever treated with oral capecitabine. The medical records of 116 patients with hepatobiliary carcinoma who were treated at The University of Texas M. D. Anderson Cancer Center (Houston, TX) between July 1998 and March 1999 were reviewed. RESULTS: A total of 63 patients were treated with capecitabine (37 with HCC, 18 with CCA, 8 with GBC). Capecitabine 1000 mg/m(2) was administered twice daily for 14 days. Treatment was repeated every 21 days. Each patient received 1-15 treatment cycles. Nine patients (14%)-11% of patients with HCC, 6% of patients with CCA, and 50% of patients with GBC-had either a complete response (CR) or a partial response. A CR was radiologically confirmed in one patient with HCC and in two patients with GBC. The median survival times were 10.1 months (95% confidence interval [CI], 4.5-15.7 months) for patients with HCC, 8.1 months (95% CI, 7.4-8.9 months) for patients with CCA, and 9.9 months (95% CI, 4.4-15.4 months) for patients with GBC. The most common toxicity was hand-foot syndrome (37%). Grade 3 thrombocytopenia occurred in 8% of patients with HCC. No other significant toxicities were observed. For all patients, response to treatment was positively correlated with survival and decline in tumor markers. CONCLUSIONS: Capecitabine was found to be safe for patients with hepatobiliary carcinoma, including those with cirrhosis. The antitumor activity of single-agent capecitabine was most pronounced in patients with GBC, was modest in patients with HCC, and was poor in patients with CCA.  相似文献   
40.
The aim of this study was to compare intra-arterial hepatic administration (IAH) versus i.v. administration of oxaliplatin and cisplatin in a VX2 tumor model in rabbits. VX2 tumors were implanted in the livers of White New Zealand female rabbits and 2 weeks later they received either cisplatin (4 mg/kg) or oxaliplatin (6 mg/kg) administered by IAH or i.v. Platinum pharmacokinetic parameters were measured by atomic absorption spectrometry at baseline, 2, 5 10, 20, 40 and 60 min, and then at 2, 4, 6 and 24 h after drug administration. Animals were sacrificed 24 h after drug administration to measure platinum concentrations in various tissues. After IAH oxaliplatin administration, we observed a significant decrease for total and filterable platinum in the Cmax compared with i.v. administration (12.4 versus 18.2 microg/l; p=0.02 and 11.2 versus 17.3 microg/l; p=0.02, respectively). Significant differences in various tissue concentrations were reported when comparing IAH and i.v. administration of oxaliplatin with IAH administration offering an advantage over i.v. administration. No differences in pharmacokinetic parameters or platinum tissue accumulation were apparent between the IAH and i.v. administration with cisplatin. We conclude that there is a significant pharmacokinetic advantage to using oxaliplatin for locoregional IAH chemotherapy compared with i.v. administration.  相似文献   
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