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Background

In recent years, new devices providing multiple channels have made the performance of laparoscopic cholecystectomy through a single access site not only feasible but much easier. The potential benefits of laparoendoscopic single-site (LESS) cholecystectomy may include scarless surgery, reduced postoperative pain, reduced postoperative length of stay, and improved postoperative quality of life. There are no comparative data between LESS cholecystectomy and standard laparoscopic cholecystectomy (LC) available at present with which to quantify these benefits.

Methods

This study was a prospective, randomized, dual-institutional pilot trial comparing LESS cholecystectomy with standard LC. The primary end point was postoperative quality of life, measured as length of hospital stay, postoperative pain, cosmetic results, and SF-36 questionnaire scores. Secondary end points included operative time, conversion to standard LC, difficulty of exposure, difficulty of dissection, and complication rate.

Results

No significant differences in postoperative lengths of stay were found in the two groups. Postoperative pain evaluation using a visual analogue scale showed significantly better outcomes in the standard LC arm on the same day of surgery (P = .041). No differences in postoperative pain were found at the next visual analogue scale evaluation or in the postoperative administration of pain-relieving medications. Cosmetic satisfaction was significantly higher in the LESS group at 1-month follow-up (mean, 94.5 ± 9.4% vs 86 ± 22.3%; median, 100% vs 90%; P = .025). Among the 8 scales of the SF-36 assessing patients' physical and mental health, scores on the Role Emotional scale were significantly better in the LESS group (mean, 80.05 ± 29.42 vs 68.33 ± 25.31; median, 100 vs 66.67; P < .0001).

Conclusions

In this pilot trial, LESS cholecystectomy resulted in similar lengths of stay and improved cosmetic results and SF-36 Role Emotional scores but performed less well on pain immediately after surgery. A larger multicenter trial is needed to confirm and further investigate these results.  相似文献   
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The V599E BRAF mutation is uncommon in biliary tract cancers.   总被引:1,自引:0,他引:1  
Activating point mutations of the BRAF oncogene have been identified in several solid tumors, most commonly in cutaneous melanomas and papillary carcinomas of the thyroid. A specific point mutation--V599E--accounts for the overwhelming majority of these mutational events. We explored the frequency of the V599E BRAF mutation in biliary tract cancers. In all, 62 archival biliary tract cancers, including 15 gallbladder cancers, 15 extrahepatic, and 10 intrahepatic cholangiocarcinomas from the United States, and 22 gallbladder carcinomas from Chile were analyzed for the V599E mutation of the BRAF gene using three distinct methods: direct sequencing, a primer extension method (Mutector assay), and the highly sensitive quantitative Gap Ligase Chain Reaction. The common V599E mutation was not identified in any of the 62 biliary cancer samples using these three methods of detection. The V599E somatic mutation of the BRAF gene is absent in biliary tract cancers, at least in the two geographic populations (United States and Chile) examined. Activation of the RAS/RAF/MAP kinase pathway in biliary tract cancers is likely to be secondary to oncogenic RAS mutations, or due to mutations of the BRAF gene at nucleotide positions not explored in the current study.  相似文献   
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There is growing interest in autologous stem cell transplantation (ASCT) for elderly patients with acute myeloid leukemia (AML). While mortality and toxicity from ASCT have been reduced, relapse rate is still high. In a prospective study, we investigated the feasibility of a new conditioning regimen consisting of high-dose idarubicin plus busulfan in AML patients aged over 60 years undergoing ASCT. A total of 14 patients (median age: 64 years) received 2 days continuous infusion of idarubicin at 20 mg/m2/day, followed by 3 days of oral busulfan (4 mg/kg/day) as conditioning. No case of transplant-related mortality occurred. The median number of days to neutrophil ( > 0.5 x 10(9)/l) and platelet ( > 20 x 10(9)/l) recovery was 11 and 12, respectively. Cardiac toxicity was absent, while 12 patients (86%) had grade 3-4 mucositis. After a median follow-up of 9 months from ASCT, nine of 14 patients are alive in continuous complete remission (CR), four have relapsed at 3, 6, 8 and 9 months, and one died in CR1 from gastric cancer. Our data demonstrate the feasibility of a conditioning regimen based on high-dose idarubicin plus busulfan in elderly AML patients. Results concerning reduction of relapse rate need confirmation in a larger series with longer follow-up.  相似文献   
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Sublobar resection for early-stage lung cancer has been used for patients who are not candidates for lobar resection. However, sublobar resection is associated with high local recurrence rates in the context of tumor-free parenchymal margins. The mechanism underlying this high recurrence rate is not well understood. We hypothesized that this elevated risk of local recurrence is due to undetected tumor cells present at parenchymal margins thought to be negative by conventional light microscopy. Thirteen of 44 patients who underwent sublobar resection for lung cancer were found to have a k-ras mutation at codon 12.1. A novel fluorescence-based assay for detection of rare copies of mutant DNA in a background of wild-type DNA, fluorescent gap ligase chain reaction, was used to quantitate the mutant/wild-type DNA in a range of 1 to 1/10,000 in histologically normal margins from these resections. Nine of 13 patients had at least one margin with the number of mutant cells over or equal to a threshold of 1/5,000, and of these, 6/9 (67%) recurred locally. None of the remaining 4 patients without mutant DNA in any surgical margin had evidence of recurrence. The higher rate of local recurrence associated with sublobar resection of lung cancer is likely due to the occult presence of tumor cells at resection margins. These occult tumor cells can be quantitated using a novel fluorescence-based assay and define a group of patients at high risk for local recurrence who are candidates for adjuvant therapy or more extensive resection. This methodology may be adaptable to a real-time format for intraoperative use.  相似文献   
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Each year approximately 40,000 people in the United States and 500,000 people worldwide are diagnosed with head-and-neck squamous cell carcinoma (HNSC). Although there have been significant improvements in the treatment of this disease, leading to decreased morbidity, over the past few decades the 5-year survival rate has remained largely unchanged at 50%. Genetic and epigenetic alterations as well as viral agents have been implicated in the development of head-and-neck cancer. Advances in our understanding of the molecular biology underlying these processes have spawned numerous, diverse strategies to exploit this understanding in applied pathology. Preliminary investigations have analyzed body fluids and margins for the presence of cancer cells. Specific molecular alterations have been associated with improved treatment response and prognosis. Molecular therapy has been shown to have some clinical efficacy in HNSC. Expression profiles may be generated for specific primary tumors and compared to known markers of disease. Improved molecular characterization of primary tumors, surgical margins and body fluids may allow clinicians to detect and treat earlier lesions, predict a tumor's response to treatment, tailor treatment to specific molecular alterations and ultimately improve clinical outcomes related to HNSC.  相似文献   
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Nasopharyngeal carcinoma (NPC) is a rare malignancy with unique genetic, viral and environmental characteristic that distinguishes it from other head and neck carcinomas. The clinical management of NPC remains challenging largely due to the lack of early detection strategies for this tumor. In our study, we have sought to identify novel genes involved in the pathogenesis of NPC that might provide insight into this tumor's biology and could potentially be used as biomarkers. To identify these genes, we studied the epigenetics of NPC by characterizing a panel of methylation markers. Eighteen genes were evaluated by quantitative methylation‐specific polymerase chain reaction (PCR) in cell lines as well as in tissue samples including 50 NPC tumors and 28 benign nasopharyngeal biopsies. Significance was evaluated using Fisher's exact test and quantitative values were optimized using cut off values derived from receiver–operator characteristic curves. The methylation status of AIM1, APC, CALCA, deleted in colorectal carcinomas (DCC), DLEC, deleted in liver cancer 1 (DLC1), estrogen receptor alpha (ESR), FHIT, KIF1A and PGP9.5 was significantly associated with NPC compared to controls. The sensitivity of the individual genes ranged from 26 to 66% and the specificity was above 92% for all genes except FHIT. The combination of PGP9.5, KIF1A and DLEC had a sensitivity of 84% and a specificity of 92%. Ectopic expression of DCC and DLC1 lead to decrease in colony formation and invasion properties. Our results indicate that methylation of novel biomarkers in NPC could be used to enhance early detection approaches. Additionally, our functional studies reveal previously unknown tumor suppressor roles in NPC.  相似文献   
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