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51.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.  相似文献   
52.
USA is experiencing a paradigm shift in public housing policy: while policies used to place people who qualified for housing assistance into spatially concentrated housing complexes, they now seek to geographically disperse them, often to voucher-subsidized rental units in the private market. Programs that relocate residents from public housing complexes tend to move them to neighborhoods that are less impoverished and less violent. To date, studies have reached conflicting findings about the relationship between public housing relocations and depression among adult relocaters. The present longitudinal multilevel analysis tests the hypothesis that pre-/postrelocation improvements in local economic conditions, social disorder, and perceived community violence are associated with declines in depressive symptoms in a cohort of African-American adults; active substance misusers were oversampled. We tested this hypothesis in a cohort of 172 adults who were living in one of seven public housing complexes scheduled for relocation and demolition in Atlanta, GA; by design, 20 % were dependent on substances and 50 % misused substances but were not dependent. Baseline data captured prerelocation characteristics of participants; of the seven census tracts where they lived, three waves of postrelocation data were gathered approximately every 9 months thereafter. Surveys were administered at each wave to assess depressive symptoms measured using the Center for Epidemiologic Studies Depression Scale (CES-D), perceived community violence, and other individual-level covariates. Participants' home addresses were geocoded to census tracts at each wave, and administrative data sources were used to characterize tract-level economic disadvantage and social disorder. Hypotheses were tested using multilevel models. Between waves 1 and 2, participants experienced significant improvements in reported depressive symptoms and perceived community violence and in tract-level economic disadvantage and social disorder; these reductions were sustained across waves 2–4. A 1 standard deviation improvement in economic conditions was associated with a 1-unit reduction in CES-D scores; the magnitude of this relationship did not vary by baseline substance misuse or gender. Reduced perceived community violence also predicted lower CES-D scores. Our objective measure of social disorder was unrelated to depressive symptoms. We found that relocaters who experienced greater pre-/postrelocation improvements in economic conditions or in perceived community violence experienced fewer depressive symptoms. Combined with past research, these findings suggest that relocation initiatives should focus on the quality of the places to which relocaters move; future research should also identify pathways linking pre-/postrelocation changes in place characteristics to changes in mental health.  相似文献   
53.
Novel techniques have recently emerged to separate chiral drug compounds into pure enantiomers. The mechanism, experimental difficulties, and applicability of these methods can vary greatly, and the choices involved are not straightforward. The most significant new advances in the field of chiral separations have come from work done with liquid chromatographic systems and chiral stationary-phase columns. This review describes several commonly used approaches to chiral separation, diastereomeric derivatization, chiral mobile-phase additives, and three major types of chiral stationary phases. Although no single method can be judged superior for every drug application, it appears that chiral stationary phases have received the most attention recently and they are emphasized here.  相似文献   
54.

Background

The current guidelines do not recommend adjuvant chemotherapy (AC) for patients with adverse pathologic findings after neoadjuvant chemotherapy (NAC) and radical cystectomy (RC) for bladder cancer. We sought to evaluate the association of AC with overall survival (OS) in these patients.

Materials and Methods

The National Cancer Database was used to identify patients with adverse pathologic findings (ypT3N0, ypT4N0, or ypTanyN1-N3) after NAC and RC for bladder cancer from 2006 to 2012. The clinicopathologic variables were abstracted, and the patients were stratified according to the receipt of AC. OS was estimated using the Kaplan-Meier method and log-rank test. Associations between AC and OS were evaluated in multivariable Cox proportional hazards regression models among all patients and stratified by pathologic classification.

Results

A total of 1361 patients were identified: 444 (32.6%) with ypT3N0, 162 (11.9%) with ypT4N0, and 755 (55.5%) with ypTanyN1-N3. The median OS for the entire cohort was 22.9 months, which differed by pathologic classification: 34.6 months with ypT3N0, 21.4 months with ypT4N0, and 19.3 months with ypTanyN1-N3 (P < .01). AC was used in 328 patients (24.1%), and no difference in OS was observed by receipt of AC (24.6 months with AC vs. 22.0 months without; P = .18). On multivariable analysis, AC was not independently associated with OS (hazard ratio, 0.86; 95% confidence interval, 0.74-1.01; P = .06).

Conclusion

Patients with adverse pathologic findings at RC after previous NAC have a median OS of approximately 2 years, which was not significantly improved with AC. Clinical trials with newer systemic agents are warranted for patients in this setting to guide future therapy.  相似文献   
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58.
SUMMARY Ninety-five patients (63 male, 32 female), age 45±2 years(mean±SEM) with chronic renal failure of varied aetiologywere randomized to receive either a conventional low proteindiet (0.6 g/kg/day protein, 800 mg phosphate; n=33), a low phosphatediet (providing approximately 1000 mg phosphate plus an orallyadministered phosphate binder, minimum protein intake 0.8 g/kg/day;n=30) or to control (minimum protein intake 0.8 g/kg/day, nophosphate restriction; n=32). Patients were reviewed for a minimumof 6 months before randomization and were withdrawn from thestudy if plasma creatinine exceeded 900 µmol/1, plasmaphosphate was > 2.0 mmol/1 or at the onset of uraemic symptoms. Following randomization patients were studied for an averageof 19±3 months. Mean plasma creatinine rose from 398±33to 600±50 µmol/1. Dietary protein intake was estimatedat 0.69±0.02 g/kg/day in the low protein group, 1.02±0.05in the low phosphate and 1.14±0.05 in the controls, phosphateintake was 815±43, 1000± 47, and 1315±57mg/day, respectively. Urinary urea excretion and protein catabolicrates were significantly reduced (p<0.01) only in those onprotein restriction, at 213±9 mmol/24 hours and 0.71g/kg/day, respectively. Phosphate excretion was significantlylower (p<0.05) in both the low protein group (17.9±0.8mmol/24 hours) and the low phosphate group (18.6±1.0mmol/24 hours) compared to controls. Changes in body weight,muscle mass and serum transferrin, albumin and immunoglobulinswere comparable between the groups. Mean blood pressure followingrandomization was 150/89±3/1 (low protein), 148/87±3/1(low phosphate) and 146/87±3/1 (controls). Progression of renal failure was analysed by rate of fall ofcreatinine clearance (ml/min/ 1.73 m2/month), by rate of deteriorationderived from reciprocal plasma creatinine against time plots(1/mmol/year) and to assess individual patient's response totreatment by two phase linear regression (‘breakpoint’)analysis of reciprocal plasma creatinine/time plots. Progressionwas analysed only in patients seen for at least 3 months followingrandomization. The rate of fall of creatinine clearance was not significantlydifferent between the groups (ANOVA): 0.56±0.08 ml/min/1.73m2/month (low protein, n=28), 0.44±0.07 (low phosphate,n=23) and 0.69±0.11 (control, n=27). In 50 patients (18low protein, 16 low phosphate and 16 control) whose rate ofprogression could be calculated before and after randomization,there was a fall in rate of progression averaging 0.18 ml/min/1.73m2/month in those on low protein diet and those on low phosphatediet, but a rise of 0.08 in the controls. These differenceswere, however, not statistically significant. Similar resultswere obtained when the rates of deterioration were calculatedfrom plasma creatinine. Significant individual improvements(p<0.01) in rates of progression by ‘breakpoint’analysis occurred in 17 patients: six on low protein, sevenon low phosphate and in four controls. Sixty-one (72 per cent)of the patients examined by this method showed no significantchange in the rate of progression while seven patients had acceleratedprogression. There was no difference in the requirement formaintenance dialysis facilities between groups. No significant benefit of protein and phosphate restrictionwas therefore demonstrated.  相似文献   
59.

Background

Salvage radiation therapy (SRT) is a recommended treatment option for biochemical recurrence after radical prostatectomy (RP). However, its effectiveness may be limited to specific categories of patients.

Objective

We aimed to identify the optimal candidates for early SRT after RP.

Design, setting, and participants

The study included 925 node-negative patients treated with SRT after RP at seven institutions. Patients received SRT for either prostate-specific antigen (PSA) rising, or PSA persistence after RP that was defined as PSA level ≥0.1 ng/ml at 1 mo after surgery. All patients received local radiation to the prostate and seminal vesicle bed.

Outcome measurements and statistical analysis

The primary outcome measured was distant metastasis after SRT. Regression tree analysis was used to develop a risk-stratification tool. Multivariable Cox regression analysis and nonparametric curve fitting methods were used to explore the relationship between PSA level at SRT and the probability of metastasis-free survival at 8 yr.

Results and limitations

At a median follow-up of 8.0 yr, 130 patients developed distant metastasis. At multivariable analysis, pre-SRT PSA level was significantly associated with distant metastasis (hazard ratio: 1.06, p < 0.0001). However, when patients were stratified into five risk groups using regression tree analysis (area under the curve: 85%), early SRT administration provided better metastasis-free survival in three groups only: (1) low risk: undetectable PSA after RP, Gleason score ≤7, and tumour stage ≥pT3b, (2) intermediate risk: undetectable PSA after RP with Gleason score ≥8, (3) high risk: PSA persistence after RP with Gleason score ≤7.

Conclusions

We developed an accurate risk stratification tool to facilitate the individualised recommendation for early SRT based on prostate cancer characteristics. Early SRT proved to be beneficial only in selected groups of patients who are more likely to be affected by clinically significant but not yet systemic recurrence at the time of salvage treatment administration.

Patient summary

In patients affected by prostate cancer recurrence after radical prostatectomy, the early administration of salvage radiation therapy is beneficial only for selected subgroups of patients. In this study, these groups of patients were identified.  相似文献   
60.
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