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21.
BACKGROUND: Recent studies evaluated the technique of direct coronary stenting as compared to stenting-after-predilation in selected anatomic and clinical settings. However, the impact of direct stenting in routine interventional practice remains poorly elucidated. METHODS: From April 1999 to March 2001, all percutaneous coronary interventions performed at our Center were prospectively analyzed to determine the frequency of direct stenting, the success rate and the variables associated with its utilization. RESULTS: 1151 lesions were treated in 835 procedures. Stenting was attempted in 835/1151 lesions (72.5%), 309 (37%) with direct stenting and 526 (63%) with stenting-after-predilation. Direct stenting was successful in 300/309 (97%) and stenting-after-predilation in 515/526 (98%). The success rate of direct stenting was significantly lower in small vessels (< or = 2.75 mm) (89.2 vs 98.5%, p = 0.005). Patients treated with direct stenting were younger (63 +/- 11 vs 65 +/- 11 years, p = 0.024). Direct stenting was preferentially used in saphenous vein grafts and at the ostium of the left anterior descending coronary artery, while it was avoided in bifurcation lesions and with increasing calcium burden. Operators with a caseload > 140 interventions per year were significantly more likely to perform direct stenting than less experienced operators (p = 0.017). In direct stenting, the total contrast medium and the fluoroscopy and procedural times were all significantly (p < 0.0001) lower than those observed in case of stenting-after-predilation. CONCLUSIONS: Direct coronary stenting is currently performed in about one third of the overall caseload. Variables pertaining to the operator's experience, lesion morphology and length, vessel size, and the clinical presentation are all important factors determining the selection of candidates suitable for direct stenting.  相似文献   
22.
Objectives: To illustrate endoscopic techniques used in the treatment of esthesioneuroblastoma and to advocate this method of management followed by radiation therapy in selected cases. Methods: A retrospective case series of 10 patients with esthesioneuroblastomas treated between 1999 and 2004 at a tertiary referral center using endonasal techniques. Results: Mean age of patients at presentation was 56.2 years (median 57 years). Seven patients were female and 3 patients were male. Kadish staging at presentation was: A - 3 patients, B - 5 patients, C - 2 patients. Dulguerov stage at presentation was: T1 - 4 patients, T2 - 4 patients, T3 - 2 patients. The period of follow-up ranged from 11 months to 74 months (mean 38.1 months, median 39 months). To date no recurrence has developed in any patient. Conclusions: Our experience suggests that endoscopic surgery can be an effective method of management. Strict attention to selection criteria, careful surgical techniques, and regular follow-up are key elements for success.  相似文献   
23.
J Machi  J Takeda  B Sigel  T Kakegawa 《Radiology》1986,159(1):85-87
Operative ultrasound examinations were performed using a 7.5-MHz transducer during nine operations for advanced gastric cancers and during six for early cancers. Normal stomach wall showed five layers that corresponded to histologic structures. Fourteen of 15 tumors, including nonpalpable early cancers, were localized with ultrasonography. In addition, both depth of penetration and lateral wall extension of the gastric cancers were precisely determined with this technique. Our preliminary results indicate that high-resolution operative ultrasonography may become a diagnostic aid during gastric cancer operations.  相似文献   
24.
Aceclofenac (A) and diclofenac (D) are effective non-steroidal anti-inflammatory drugs (NSAIDs) derived from the phenylacetic acid with pronounced antirheumatic, anti-inflammatory, analgesic and antipyretic properties. Our work proposes a new, fast-free zone capillary electrophoresis method for the simultaneous determination of aceclofenac and diclofenac in human plasma. The effect of increasing concentrations of N-methyl-D-glucamine organic base on borate run buffer was investigated. A good separation was achieved using a 40 cm x 75 microm uncoated silica capillary, 300 mmol/l sodium borate buffer, 200 mmol/l N-methyl-D-glucamine, pH 8.9, in about 3 min. Moreover, the plasma sample pre-treatment procedure was examined: acidic precipitants such as trichloroacetic acid (TCA), metaphosphoric acid (MPA), perchloric acid (PCA) or 5-sulphosalicylic acid (SSA) cause a total loss of analytes while acetonitrile allows a recovery of 97-98% of both compounds. Its simplicity and rapidity and the low analysis costs demonstrate that our method is a reliable and efficient mean for the comprehensive determination of aceclofenac and diclofenac in human plasma when pharmacokinetics studies are required.  相似文献   
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26.
The chain propagation rate constants for the polymerization of ethylene and propene in the presence of δ-TiCl3/Al(CH3)3 at 22 °C are determined by means of a 13C NMR analysis of suitable block copolymers. The numerical values of the rate constants are compared with those previously reported.  相似文献   
27.
Prevalence of isolated left ventricular (LV) diastolic dysfunction has been reported to be as high as one-third of all heart failure (HF) cases, with an increasing prevalence in the elderly population. However, there is a paucity of prospective data about the prevalence and prognosis of isolated LV diastolic dysfunction in an unselected population of patients hospitalized with HF. Therefore, we prospectively evaluated 179 consecutive patients discharged from our hospital with HF to assess the prevalence of systolic versus diastolic LV dysfunction among patients hospitalized with HF and to compare their demographics, clinical features, self-perceived quality of life (QOL), and 6-month readmission rate and mortality. Among them, 133 (59% men, median age 74 years) showed in sinus rhythm and had no significant primary valvular disease. LV diastolic dysfunction was diagnosed on the basis of the European Study Group on Diastolic HF echocardiographic criteria. QOL was assessed at hospital discharge and 6-month follow-up visit using the Minnesota Living with HF questionnaire. Survival of patients with HF was compared with that of age- and sex-matched general population. In all, 29 patients (22%) had isolated LV diastolic dysfunction and 102 (78%) had prevalent LV systolic dysfunction (ie, LV ejection fraction 相似文献   
28.
Porcelain heart     
A 65-year-old hypertensive man with shortness of breath andatypical thoracic pain underwent coronary angiography for  相似文献   
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30.
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk.  相似文献   
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