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61.
Background BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02 was studied in vivo in mice. Methods and Results Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%) and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02 had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization and demonstrated sustained myocardial uptake through 55 minutes. Conclusions F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake and slow washout. These characteristics allow fast and sustained accumulation in the heart.  相似文献   
62.
Although tumors consisting of a combination of transitional cell carcinoma (TCC) and adenocarcinoma have been described in the endometrium, they have not been documented in the uterine cervix to our knowledge. Three such cervical cases are reported in this article. Three patients, whose ages ranged from 40 to 61 years, presented with vaginal bleeding and malignant cells on routine Papanicolaou smears. The initial diagnoses based on a biopsy specimen were poorly differentiated squamous cell carcinoma in two patients and adenocarcinoma with a solid component in the third patient. All patients underwent radical hysterectomy. The hysterectomy specimens each contained a polypoid endocervical mass with minimal invasion of the cervical stroma. On microscopic examination, each tumor consisted of a component of papillary TCC admixed with an adenocarcinoma of endometrioid type. Both carcinomatous components were immunoreactive for cytokeratin (CK) 7 but not CK20. The three patients were alive and disease-free from 10 months to 4 years postoperatively. Recognition of this unusual variant of cervical carcinoma is important to delineate its clinical and pathologic features and establish prognostic differences, if any, from other histologic subtypes of cervical carcinoma. Papillary TCC mixed with adenocarcinoma broadens the morphologic spectrum of transitional cell neoplasms of the uterine cervix.  相似文献   
63.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
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65.
BACKGROUND: Recently, epidemiological and clinical data have revealed important changes with regard to clinical adenovirus infection, including alterations in antigenic presentation, geographical distribution, and virulence of the virus. METHODS: In an effort to better understand the epidemiology of clinical adenovirus infection in the United States, we adopted a new molecular adenovirus typing technique to study clinical adenovirus isolates collected from 22 medical facilities over a 25-month period during 2004-2006. A hexon gene sequence typing method was used to characterize 2237 clinical adenovirus-positive specimens, comparing their sequences with those of the 51 currently recognized prototype human adenovirus strains. In a blinded comparison, this method performed well and was much faster than the classic serologic typing method. RESULTS: Among civilians, the most prevalent adenovirus types were types 3 (prevalence, 34.6%), 2 (24.3%), 1 (17.7%), and 5 (5.3%). Among military trainees, the most prevalent types were types 4 (prevalence, 92.8%), 3 (2.6%), and 21 (2.4%). CONCLUSIONS: For both populations, we observed a statistically significant increasing trend of adenovirus type 21 detection over time. Among adenovirus isolates recovered from specimens from civilians, 50% were associated with hospitalization, 19.6% with a chronic disease condition, 11% with a bone marrow or solid organ transplantation, 7.4% with intensive care unit stay, and 4.2% with a cancer diagnosis. Multivariable risk factor modeling for adenovirus disease severity found that age <7 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4-7.4), chronic disease (OR, 3.6; 95% CI, 2.6-5.1), recent transplantation (OR, 2.7; 95% CI, 1.3-5.2), and adenovirus type 5 (OR, 2.7; 95% CI, 1.5-4.7) or type 21 infection (OR, 7.6; 95% CI, 2.6-22.3) increased the risk of severe disease.  相似文献   
66.
The purposes of the present study of chronic pain patients were to (a) assess whether cognitive and behavioral coping style is related to personality factors, (b) assess how coping styles differ across personality types, and (c) assess how outpatient interdisciplinary intervention affects the coping styles of various personality types. Four MMPI clusters (Depression/Pathological, V-type, Marginal Depression, and Marginal V-type) were derived using a hierarchical clustering procedure. Seventy subjects also completed the Coping Strategies Questionnaire before and after a 3-week outpatient pain management program. Pretreatment analyses indicated the Depression/Pathological and Marginal Depression groups used diverting attention less than either V-type group. The V-type group reported using praying/hoping significantly more than either of the marginal groups. At posttreatment the Depression/Pathological group used catastrophizing significantly more than either of the marginal groups. Results of pre-post analyses indicated that the Depression/Pathological group increased their use of diverting attention, reinterpreting pain sensations, and ignoring pain sensations, while decreasing catastrophizing. The V-type group increased their use of reinterpreting pain sensations, while decreasing praying/hoping and catastrophizing. Neither of the Marginal subtypes showed significant pre-post changes in coping strategies. These results suggest that different personality types use different pain coping strategies prior to multidisciplinary treatment. Groups showing more severe psychological distress, perhaps related to an underlying personality disorder, displayed greater changes in coping strategies with treatment, but remained more dysfunctional after treatment. These findings suggest that the alteration of coping strategies may be an important treatment effect needing more individualization to maximize treatment response.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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68.
Postprostatectomy incontinence in men is a devastating condition impacting the quality of life profoundly. Various types of male sling procedures have been introduced over the years. The bone-anchored male sling appears to be effective and safe in intermediate-term follow-up. It is certainly more effective than collagen implant and may provide an alternative treatment option in patients with mild to moderate incontinence. In the short term, other novel procedures seem promising. In spite of new technology, the artificial urinary sphincter continues to provide high patient satisfaction and cure rates.  相似文献   
69.
70.
The purpose of this study was to appraise the value of PET in the assessment of the effect of supposedly proangiogenic new therapies such as gene therapy with vascular endothelial growth factor (VEGF) gene and endomyocardial laser therapy. METHODS: Thirty-five patients with end-stage coronary artery disease and class III (Canadian Cardiovascular Society) angina were included. Myocardial ischemia was evaluated with dipyridamole PET scanning and exercise tolerance with bicycle ergometry. Ten patients were treated with naked plasmid DNA encoding for human VEGF165 (VEGF) and 12 patients were treated with laser therapy (direct myocardial revascularization [DMR]) using an electromechanical mapping system. Thirteen patients were treated with standard medical therapy (control). RESULTS: In both active treatment groups, angina was reduced in most subjects, except in 2 VEGF and 5 DMR patients. In the control group, no improvement in anginal classification was found, except in 3 subjects. On the PET scan, solely in the VEGF group, the stress perfusion was significantly improved (from 57 +/- 33 to 81 +/- 55 mL/min/100 g; P = 0.031). Furthermore, in the VEGF group, the number of ischemic segments was reduced from 274 +/- 41 to 234 +/- 48 segments (P = 0.004) but not in the DMR group (from 209 +/- 43 to 215 +/- 52 segments) or in the control group (from 218 +/- 18 to 213 +/- 28 segments). Bicycle exercise duration showed slight nonsignificant changes in the VEGF group (from 3.6 +/- 2.0 to 4.6 +/- 2.1 min), in the DMR group (from 5.1 +/- 1.5 to 4.7 +/- 1.3 min), and in the control group (from 3.3 +/- 1.8 to 3.5 +/- 2.3 min). CONCLUSION: PET showed that intramyocardial gene therapy with the human VEGF165 gene in contrast to laser DMR treatment effectively reduces myocardial ischemia.  相似文献   
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