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Percutaneous transluminal angioplasty of the femoropopliteal artery: initial and long-term results 总被引:4,自引:0,他引:4
Patients with dilated stenoses and recanalized occlusions were evaluated to assess the initial and long-term results of percutaneous transluminal angioplasty (PTA) in the femoropopliteal artery. The follow-up period was at least 1 year. The initial success rate was 84% (128/164). The initial results were influenced by the radiologist's experience, catheter selection, and type of lesion. The 5- and 7-year cumulative patency rates were 70% and 60%. There was no difference in long-term patency between initially successful stenoses and short (less than 3 cm) occlusions. Both the morphology and location of the stenotic lesion influenced the long-term results. Although many factors influence the initial and long-term success rate, results of this study justify PTA in the femoropopliteal artery. Patients with localized stenoses and short occlusions are best suited for this treatment. 相似文献
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Triple-balloon dilation (TBD) of a variety of luminal structures has been successfully, though infrequently, used. A mathematical model is presented for the selection of balloon sizes, and equations and tables are derived that allow the user to estimate more accurately the size of balloons needed for TBD of structures with large lumina. With TBD, an approximately circular lumen can be formed. Also, TBD allows smaller, higher-pressure balloons to be used instead of single, low-pressure, large balloons. However, multiple puncture sites may be required for TBD. 相似文献
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Gray-scale ultrasonography of the normal female pelvis 总被引:5,自引:0,他引:5
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Crepaz N Lyles CM Wolitski RJ Passin WF Rama SM Herbst JH Purcell DW Malow RM Stall R;HIV/AIDS Prevention Research Synthesis 《AIDS (London, England)》2006,20(2):143-157
OBJECTIVE: To conduct a meta-analytic review of HIV interventions for people living with HIV (PLWH) to determine their overall efficacy in reducing HIV risk behaviours and identify intervention characteristics associated with efficacy. METHODS: Comprehensive searches included electronic databases from 1988 to 2004, hand searches of journals, reference lists of articles, and contacts with researchers. Twelve trials met the stringent selection criteria: randomization or assignment with minimal bias, use of statistical analysis, and assessment of HIV-related behavioural or biologic outcomes at least 3 months after the intervention. Random-effects models were used to aggregate data. RESULTS: Interventions significantly reduced unprotected sex [odds ratio (OR), 0.57; 95% confidence interval (CI) 0.40-0.82] and decreased acquisition of sexually transmitted diseases (OR, 0.20; 95% CI, 0.05-0.73). Non-significant intervention effects were observed for needle sharing (OR, 0.47, 95% CI, 0.13-1.71). As a whole, interventions with the following characteristics significantly reduced sexual risk behaviours: (1) based on behavioural theory; (2) designed to change specifically HIV transmission risk behaviours; (3) delivered by health-care providers or counsellors; (4) delivered to individuals; (5) delivered in an intensive manner; (6) delivered in settings where PLWH receive routine services or medical care; (7) provided skills building, or (8) addressed a myriad of issues related to mental health, medication adherence, and HIV risk behaviour. CONCLUSION: Interventions targeting PWLH are efficacious in reducing unprotected sex and acquisition of sexually transmitted diseases. Efficacious strategies identified in this review should be incorporated into community HIV prevention efforts and further evaluated for effectiveness. 相似文献
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TFR Homfray SE Cottrell M Ilyas A Rowan IC Talbot WF Bodmer IPM Tomlinson 《Human mutation》1998,11(2):114-120
The roles of the intrinsic mutation rate and genomic instability in tumorigenesis are currently controversial. In most colorectal tumours, it is generally supposed that the first mutations occur at the adenomatous polyposis coli (APC) locus; APC mutations are thought to provide cells with a selective advantage but have no known effect on the mutation rate. It has also been suggested that genomic instability is the initiating event in colorectal tumorigenesis and, if this is true, mutations of DNA mismatch repair (MMR) genes (or at similar loci) are the most likely candidates. If defective MMR precedes APC mutations, the APC mutations of colon tumours with defective MMR and hence replication errors (RER+) should differ from those of RER- tumours, in at least three specific ways: (1) a higher frequency of allele loss at APC in RER- tumours; (2) more frameshift than nonsense mutations in RER+ tumours; and (3) APC mutations in simple repeat sequences [(N)n, (N1N2)n, or (N1N2N3)n] in RER+ tumours. We found no evidence that sporadic RER+ and RER- colon cancers (including cell lines) differ in any of these three ways. Although it remains possible that MMR is abnormal in tumours from HNPCC families before APC mutations occur, it is likely that in sporadic colon tumours, APC mutations, rather than genomic instability, are the initiating events in tumorigenesis. Hum Mutat 11:114–120, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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Passin WF Kim AS Hutchinson AB Crepaz N Herbst JH Lyles CM;HIV/AIDS Prevention Research Synthesis Project Team 《Sexually transmitted diseases》2006,33(5):320-328
OBJECTIVES: The objectives of this study were to understand client and provider attitudes, experiences, and practices regarding HIV partner notification in the United States and to help identify future research and program needs. GOALS: The goals of this study were to synthesize the literature reporting client and provider attitudes, experiences, and practices and to identify potential negative effects of HIV partner notification. STUDY DESIGN: This study consisted of a systematic qualitative review. RESULTS: Clients were willing to self-notify partners and participate in provider notification, and few reported negative effects. The majority of health care providers were in favor of HIV partner notification; however, they did not consistently refer index clients to HIV partner notification programs. CONCLUSION: Considering that clients have positive attitudes toward self- and provider referral, local HIV prevention programs need to ensure that all HIV-positive clients are offered partner notification services. Additional research is needed to assess the potential risks of notifying partners and to identify effective techniques to improve client and provider participation. 相似文献