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981.
This study examines the role of key informant community readiness assessments in a randomized group trial testing the impact of a participatory community-media intervention (which was also complemented by in-school efforts). These assessments were used to help match communities in random assignment, as a source of formative data about the community, as the basis for a coalition-building workshop, and as an evaluation tool, with a follow-up set of surveys approximately 2 years after the baseline survey. Results of the nested, random effects analysis indicated that the intervention influenced community knowledge of efforts and (at marginally significant levels) improved prevention leadership quality and community climate supportive of prevention efforts. There was evidence that the professional affiliation of informants in some cases had an effect on their assessments, which could be controlled in the analysis. The authors conclude that key informant community readiness assessments can usefully serve to supplement aggregated measures of individual attitudes and behavior (reported elsewhere for this study) in evaluating community-based interventions.  相似文献   
982.
983.
Efficacy of unilateral nerve sparing in radical perineal prostatectomy   总被引:1,自引:0,他引:1  
AIM: We determine the efficacy of unilateral nerve-sparing radical perineal prostatectomy in preserving the sexual function. PATIENTS AND METHODS: Ninety-two patients with histologically confirmed unilateral prostate cancer were scheduled for contralateral nerve preservation. The perioperative morbidity was assessed using the patients' chart reviews. Postoperative health-related quality of life, urinary continence, and potency were evaluated prospectively with questionnaires provided before surgery and then after 6, 12, and 24 months. RESULTS: Unilateral nerve preservation was performed in 88 of the 92 patients. Due to extensive scarring or prostatic size, the procedure was terminated as regular radical prostatectomy in 4 other patients. The perioperative complication rate was low and of minor significance, except in 1 patient who experienced a significant myoglobulinuria due to a prolonged procedure. Blood transfusions were necessary in 5 (5.4%) patients. Ureteral reimplantation was performed in 1 patient because of ureteral stricture. Positive surgical margins were present in 12 (18%) of 67 pT2 patients and in 8 (35%) of 23 pT3 patients. A proportion of 48% (15/31) of the patients followed for more than 24 months and who had a good erectile function prior to surgery reported unassisted sexual intercourse. However, only 4 of these patients were completely satisfied with all aspects of sexual performance, as asked in a short version of the International Index of Erectile Function questionnaire. CONCLUSIONS: Unilateral nerve-sparing radical perineal prostatectomy is technically feasible and yields excellent results in terms of potency preservation for prostates <60 ml. However, the quality of erections is decreased, even in patients with erections sufficient for intercourse. Hence, appropriate sexual counseling in conjunction with medical therapy should be offered to all patients.  相似文献   
984.
BACKGROUND: Insulin-like growth factor-I (IGF-I) is a potent mitogen for both normal and malignant prostate epithelial cells. The majority of circulating IGF-I is bound in a complex with IGF binding protein-3 (IGFBP-3), which in turn limits IGF-I bioavailability. Multiple studies suggest that higher IGF-I and/or lower IGFBP-3 serum levels are positively associated with prostate cancer risk. Several polymorphisms within the IGF-I and IGFBP-3 coding regions have been associated with increased serum protein levels. METHODS: To ascertain the potential relationship between serum levels and polymorphism, and prostate cancer risk, we investigated the role of two polymorphisms the IGF-I cytosine-adenosine (CA)-repeat and the IGFBP-3 Ala32Gly, and prostate cancer in a population-based, case-control, study of middle-aged men. RESULTS: We found no significant association between the IGFBP-3 Ala32Gly polymorphism and prostate cancer risk, even though the presence of at least one Gly allele did correlate with increased serum levels of IGFBP-3. For IGF-I, more controls (42%) than cases (38%) were homozygous for 19-CA-repeats (odds ratio, OR = 0.85; 95% confidence interval (CI) = 0.66-1.09). After stratifying by disease characteristics, 19-CA-repeat homozygous men displayed a decreased risk of low-grade disease (OR = 0.50; 95% CI = 0.27-0.93), but no associations were observed with more aggressive features of disease. Additionally, there was no correlation between mean serum IGF-I protein levels and IGF-I genotype in controls. CONCLUSIONS: Further evaluation of the IGF-I CA-repeat polymorphism and prostate cancer is necessary to determine if the modest risk reduction associated with the 19-CA-repeat homozygous state is observed in other study populations.  相似文献   
985.
PURPOSE: To evaluate the MRI compatibility of 15 different commercially available, new generation, U.S. Food and Drug Administration (FDA)-approved stents suitable for deployment in superficial femoral arteries (SFAs), and to identify the ones that permit MRI to visualize the wall and lumen of stented arteries with sufficient spatial and contrast resolution to quantify restenosis after stent placement. MATERIALS AND METHODS: A total of 13 nitinol stents and two stainless-steel stents were placed in excised cadaveric SFAs and imaged by MRI at 1.5 T ex vivo. The images were evaluated qualitatively for the presence of artifacts and for the effects of the stent on image contrast, and quantitatively for the effect on signal-to-noise ratio (SNR) of the lumen of the artery inside the stent compared to the SNR of the fluid outside the artery. A nitinol stent was placed in the SFA of a 60-year-old man and imaged at 1.5 T in vivo. RESULTS: Both the vessel wall and the lumen could be visualized in cadaveric SFAs containing either the Absolute nitinol stent, the Dynalink nitinol stent, or the aSpire nitinol-covered stent. Their inside stent/outside stent SNR was 0.7, 0.8, and 0.8, respectively. The other 10 nitinol stents tested obscured the lumen but did not cause major image shape artifacts. Both stainless-steel stents tested, the WallGraft and WallStent, completely obscured the lumen and caused significant distortion of the image shapes. When the Dynalink stent was inserted into a highly stenosed SFA in vivo, the image showed a dark expanded eccentric lumen, circumscribed by a medium intensity band containing the stent. CONCLUSION: MRI can be used to visualize both the lumen and wall of SFAs containing selected nitinol stents ex vivo and in vivo. These results suggest that MRI can be used to monitor restenosis in stents placed in the femoral arterial bed.  相似文献   
986.
In this study, in vivo evaluation in mice and rabbits of [123I]-4-iodo-N-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)butyl)-benzamide ([123I]-BPB), a potential radioligand for visualisation of the sigma receptor by single photon emission computed tomography (SPECT), is reported. The compound possesses appropriate lipophilicity (log P=2.2) and binds sigma-1 and sigma-2 receptors (pKi=6.51 and 6.79, respectively). In mice, this new radioiodinated tracer exhibited high brain uptake (4.99% ID/g tissue at 10 min postinjection) and saturable binding (3.06% ID/g tissue at 10 min postinjection) as determined by pretreatment with unlabeled [123I]-BPB. A metabolite study demonstrated no (less than 5%) labeled metabolites in the brain. In rabbits, regional brain distribution was investigated and the tracer displayed high, homogeneous central nervous system uptake. Selectivity was assessed by competition experiments with known sigma ligands. Metabolite analysis showed no (less than 8%) labeled metabolites in the rabbit brain. In conclusion, our findings indicate that [123I]-BPB is not a suitable tracer for visualisation of D3 receptors while its potential for sigma receptor imaging is severely hampered by its affinity for dopamine receptors.  相似文献   
987.
[(123)I]-3-(4-iodobenzyl)-1,2,3,4-tetrahydro-8-hydroxychromeno[3,4-c]pyridin-5-one ([(123)I]-ITCP), a presumed radioligand for visualization of the dopamine D4 receptor by single photon emission computed tomography, was evaluated in vivo in mice and rabbits. This new radioiodinated tracer exhibited high brain uptake (3.64% injected dose per gram of tissue at 10 min p.i.) in mice. No significant amounts (less than 5%) of labeled metabolites were present in the brain, as demonstrated by a metabolite study. Regional brain distribution in rabbits showed atypical CNS uptake with consistently low values in the cortex and high values in other brain parts including cerebellum. Saturable binding was confirmed by a competition experiment with unlabeled product. Selectivity was assessed by competition experiments with a known dopamine D4 ligand and later with a sigma receptor ligand. Both experiments showed no observable competition. In conclusion, our findings indicate that [(123)I]-ITCP is neither a dopamine D4 receptor ligand nor a sigma receptor ligand. The exact nature of [(123)I]-ITCP binding in the brain remains to be elucidated.  相似文献   
988.
989.
990.
The key points of this article are anorexia and cachexia are: A major cause of cancer deaths. Several drugs are available to treat anorexia and cachexia. Dyspnea in cancer usually is caused by several factors. Treatment consists of reversing underlying causes, empiric bronchodilators, cortico-steroids--and in the terminally ill patients-opioids, benzodiazepines,and chlorpromazine. Delirium is associated with advanced cancer. Empiric treatment with neuroleptics while evaluating for reversible causes is a reasonable approach to management. Nausea and vomiting are caused by extra-abdominal factors (drugs,electrolyte abnormalities, central nervous system metastases) or intra-abdominal factors (gastroparesis, ileus, gastric outlet obstruction, bowel obstruction). The pattern of nausea and vomiting differs depending upon whether the cause is extra- or intra-abdominal. Reversible causes should be sought and empiric metoclopramide or haloperidol should be initiated. Fatigue may be caused by anemia, depression, endocrine abnormalities,or electrolyte disturbances that should be treated before using empiric methylphenidate. Constipation should be treated with laxatives and stool softeners. Both should start with the first opioid dose.  相似文献   
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