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51.
OBJECTIVES: To evaluate the efficacy and toxic effects of intensive chemoradiotherapy as a primary modality for organ preservation in patients with advanced squamous cell carcinoma of the head and neck (SCCHN) and to define the patterns of treatment failure associated with this therapy. DESIGN: Retrospective review. SETTING: Tertiary care referral center. PATIENTS: A total of 127 consecutive patients with advanced SCCHN treated with primary concurrent chemoradiotherapy. MAIN OUTCOME MEASURES: Efficacy data included the rates of tumor response to therapy, organ preservation, disease recurrence, overall and disease-specific survival, and patterns of treatment failure. Toxic effect data included the rate and grade of treatment-related complications and the rate of unscheduled hospital admissions for managing treatment-related toxic effects. RESULTS: Ninety-six patients (76%) were men and 31 (24%) were women. Average age at diagnosis was 62 years (range, 37-85 years). The primary tumor site was the oropharynx in 58 patients (46%), the larynx in 36 (28%), the hypopharynx in 20 (16%), the oral cavity in 10 (8%), and another site in 3 (2%). Most patients (91%) had stage III or IV disease. Average follow-up was 36 months. Primary chemoradiotherapy achieved complete response at the primary tumor site in 109 patients (86%). Patients with partial response, stable or progressive disease, or recurrence at the primary site underwent salvage surgery. Overall, at mean follow-up of 3 years, local disease control was achieved in 113 patients (89%), and organ preservation was possible in 102 patients (80%). Two thirds of all patients (n = 83) had clinical N+ disease. Complete clinical response to chemoradiotherapy in the neck was achieved in 57 of these patients (69%). However, complete response to chemoradiotherapy was 93%, 62%, and 47% for N1, N2, and N3 disease, respectively (P <.001). Patients achieving less than complete clinical response underwent salvage neck dissection. Overall, at an average follow-up of 36 months, regional disease control was achieved in 76 (92%) of the 83 patients with neck metastasis. Despite this high locoregional control rate, distant metastasis occurred in 18 patients (14%), was the most common site of disease recurrence (53%), and accounted for almost 40% of all treatment failures. Severe (grade 3 or 4) mucositis and neutropenia occurred in 33% and 25% of patients, respectively. Two patients (2%) died of treatment-related toxic effects. At 3-year mean follow-up, disease-specific and overall survival were 72% and 57%, respectively. Most deaths were due to distant metastasis, comorbidity, and second primary tumors. CONCLUSIONS: High rates of locoregional disease control and organ preservation are achievable with primary chemoradiotherapy in patients with advanced SCCHN, but they are associated with severe treatment-related toxic effects. Despite this effective local and regional disease control, improved survival is hampered by the relatively high incidence of distant metastasis, second primary tumors, and comorbidity.  相似文献   
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Prosthetic dialysis access thrombosis and/or stenosis is the most common cause of graft impairment or loss and is primarily attributed to venous outflow stenosis due to intimal hyperplasia. Intimal hyperplasia is thought to result from interactions between areas of exposed subendothelial collagen in an injured vessel and platelets, resulting in platelet adhesion. Saratin, an inhibitor of the vWF-dependent binding of platelet to collagen interaction, has been shown in vitro to reduce the adhesion of platelets to collagen. In the current study, the authors investigated the effects of topical saratin administration in a canine dialysis access model in regard to intimal hyperplasia development at the venous anastomosis. Fourteen female mongrel dogs underwent placement of a femoral polytetrafluoroethylene (PTFE) dialysis access graft and were placed into 1 of 2 groups: 1) control or 2) experimental with topical saratin application. The experimental group had 600 microg of saratin (1 microg/microL) applied for 5 minutes directly onto the venous anastomosis before restoration of blood flow;control groups received vehicle control. At 4 weeks postoperative, a portion of the graft was removed along with a segment of the outflow vein. Veins were subsequently processed, sectioned, and analyzed along the length of the excised segment and divided into blocks that included the area of the graft toe, midanastomotic region and heel, and blocks A-E. Intimal hyperplasia was assessed by a computer-assisted morphometric analysis. Platelet counts and bleeding times were also measured. Vein segments in the control group (n=7) showed pronounced intimal hyperplasia in blocks B, C, and D as compared to the saratin group (n=6). Distribution of intimal hyperplasia by blocks between control and saratin groups were as follows: block [A] 8.6 +/- 1.9 vs 9.7 +/- 3.0% (p=NS), [B] 32.7 +/- 6.3 vs 10.7 +/- 3.5% (p=0.01), [C] 44.8 +/- 6.2% vs 10.3 +/- 1.5% (p=0.0004), [D] 40.8 +/- 11.0 vs 9.1 +/- 4.2% (p=0.02), [E] 7.5 +/- 5.5 vs 2.7 +/- 0.4% (p=NS). Intimal hyperplasia normalized to vein wall thickness also showed a significant reduction with saratin application. Bleeding times and platelet counts obtained at different time points during the experiment showed no difference between control and saratin groups. In a canine dialysis access model using PTFE grafts, topical application of saratin at the venous anastomosis decreased intimal hyperplasia development by as much as 77% when compared with control animals. Saratin provides for a method of substantially reducing intimal hyperplasia by direct local application without systemic side effects.  相似文献   
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程静  李春洋 《中国妇幼保健》2006,21(22):3071-3073
目的探讨小剂量孕激素能否辅助预防多囊卵巢综合征(PCOS)促排卵中出现的卵泡未破裂黄素化综合征(LUFS)。方法将PCOS患者在促排卵治疗中确诊为LUFS的病人28例作为研究对象,在治疗周期的卵泡成熟日同时注射黄体酮5mg、人绒毛膜促性腺激素(HCG)5000IU,观察卵子的排出情况。在LUFS周期和治疗周期的HCG日和HCG、黄体酮注射后30h测定血中促黄体生成素(LH)、雌二醇(E2)和孕酮(P)并进行比较。结果LUFS周期HCG注射前后血清中LH、E2和P无明显变化;治疗周期HCG+P注射后30h血中P明显升高,与注射前相比差异有显著性,E2和P变化不明显;治疗周期中27例成功排卵。结论小剂量孕激素能辅助预防PCOS促排卵中出现的LUFS。  相似文献   
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AIM: To investigate the frequency and distribution of N-acetyltransferase 2 (NAT2) and uridine 5'-diphosphate (UDP)-glucuronosyltransferase 1A7 (UGT1A7) genes in patients with ulcerative colitis (UC) and Crohn's disease (CO). METHODS: Frequencies and distributions of NAT2 and UGT1A7SNPs as well as their haplotypes were investigated in 95 patients with UC, 60 patients with CD, and 200 gender-matched, unrelated, healthy, control volunteers by PCR-restriction fragment length polymorphism (RFLP), PCR-denaturing high-performance liquid chromatography (DHPLC), and direct DNA sequencing. RESULTS: Multiple logistic regression analysis revealed that the frequency of haplotype, NAT2*7B, significantly increased in CD patients, compared to that in controls (P=0.0130, OR = 2.802,95%CI = 1.243-6.316). However, there was no association between NAT2 haplotypes and UC, or between any UGT1A7 haplotypes and inflammatory bowel disease (IBD). CONCLUSION: It is likely that the NAT2 gene is one of the determinants for CD in Japanese. Alternatively, a new CD determinant may exist in the 8p22 region, where NAT2 is located.  相似文献   
57.
Expression of pituitary tumor transforming gene in human gastric carcinoma   总被引:4,自引:0,他引:4  
AIM: Pituitary tumor transforming gene (PTTG1) is overexpressed in a variety of tumors, including carcinomas of the lung, breast, colon, as well as in leukemia, lymphoma and pituitary adenomas. However, there is little information on its expression in gastric carcinoma. We sought to investigate the expression of PTTG1 in gastric carcinoma and to explore the relationship between its expression and clinicopathological factors. METHODS: We studied 75 primary human gastric adenocarcinomas, including 17 mucosal carcinomas, 21 submucosal infiltrative carcinomas, 12 carcinomas invading proprial muscle layers, 6 carcinomas reaching the subserosa, and 19 carcinomas penetrating the serosal surface. Immunohistochemical analysis was performed using paraffin-embedded sections of gastric adenocarcinomas. RESULTS: PTTG1 was expressed heterogeneously in carcinomas. Positive PTTG1 staining was observed in 65.3% of the carcinomas (49 of 75). Its expression did not correlate significantly with either the histological type or the depth of infiltration of the gastric carcinomas. However, a statistical analysis showed significant differences between the primary adenocarcinomas and the associated metastatic lymph nodes. CONCLUSION: The results of this study demonstrate that PTTG1 expression is enhanced in metastatic lymph nodes in comparison to that in primary carcinomas. We suggest that PTTG1 may contribute to lymph node metastases in gastric carcinoma.  相似文献   
58.
Systemic delivery of small interfering RNA (siRNA) into cancer cells remains the major obstacle to siRNA drug development. An ideal siRNA delivery vehicle for systemic administration should have long circulation time in blood, accumulate at tumor site, and sufficiently internalize into cancer cells for high-efficiency of gene silence. Herein, we report a core–shell Micelleplex delivery system that made from block copolymer bearing poly(ethylene glycol) (PEG), matrix metalloproteinase 2 (MMP-2)-degradable peptide PLG*LAG, cationic cell penetrating peptide polyarginine r9 and poly(ε-caprolactone) (PCL) for siRNA delivery. We show clear evidences in vitro and in vivo to prove that the micelle carrying siRNA can circulate enough time in blood, enrich accumulation at tumor sites, shed the PEG layer when triggered by tumor overexpressing MMP-2, and then the exposing cell penetrating peptide r9 enhanced cellular uptake of siRNA. Accordingly, this design strategy enhances the inhibition of breast tumor growth following systemic injection of this system carrying siRNA against Polo-like kinase 1, which demonstrating this Micelleplex can be a potential delivery system for systemic siRNA delivery in cancer therapy.  相似文献   
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Background:This meta-analysis aimed to synthesize randomized controlled trials to evaluate the effects of enhanced external counterpulsation (EECP) on exercise capacity and quality of life in patients with chronic heart failure (CHF).Methods:Both English and Chinese databases were searched from their inception to June 30, 2020 (PubMed, EMBASE, Cochrane Library, CINAHL (EBSCO), Web of Science for English publications and Chinese Biomedical Database, China National Knowledge Infrastructure, Wanfang Data for Chinese publication). Titles, abstracts, and full-text articles were screened against study inclusion criteria: randomized controlled trials studying EECP intervention for patients with CHF. The meta-analysis was conducted with Revman 5.3 or STATA 16.0.Results:Eight randomized controlled trials were included. EECP induced significant improvement in 6-min walking distance (WMD=84.79 m; 95% CI, 47.64 to 121.95; P < .00001). Moreover, EECP was beneficial for left ventricular ejection fraction (SMD = 0.64; 95% CI,0.29 to 1.00; P = .0004), and N-terminal pro brain natriuretic peptide (SMD = −0.61; 95%CI, −1.20 to −0.01; P = 0.04).However, compared with the control groups, EECP did not significantly reduce the Minnesota Living with Heart Failure Questionnaire scores(WMD, −9.28; 95% CI, −19.30 to 0.75; P = 0.07).Conclusions:Despite heterogeneity and risk of bias, this meta-analysis confirms that EECP can improve exercise capacity in CHF patients, especially the elderly. However, the evidence that EECP improves the quality of life in patients with CHF is still insufficient. More and larger well-designed randomized controlled trials are still warranted.Registration information:PROSPERO registration no. CRD 42020188848.  相似文献   
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