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81.
Telechelic aromatic diamines ( 11 ) containing an oligo- or polysiloxane chain were prepared in a 4-step synthesis. In the first step 1-allyloxy-4-nitrobenzene ( 6 ) was synthesized and subsequently hydrosilylated with chlorodimethylsilane. In the third step the product ( 7 ) was hydrolyzed or condensed with α-hydro-β-hydroxyoligo- or polydimethylsiloxane ( 9a or 9b ). In the last step the nitro groups were reduced into amino groups. The steps were controlled by means of 1H and 29Si NMR spectroscopy.  相似文献   
82.
In our sample of 15 hospitalized patients with severe psychotic depression, six responded to therapy with tricyclic antidepressants combined with neuroleptics. Of the nine nonresponders, eight showed an excellent clinical response to electroconvulsive therapy (ECT). The clinical outcome after 6 months of treatment was similar in both groups. We recommend that protracted, complicated trials of pharmacotherapy be reevaluated in psychotic depression. A prospective comparative study of ECT and pharmacotherapy is needed to define the optimal treatment for psychotic depression.  相似文献   
83.
A study of caries experience and gingivitis prevalence in 6-, 9- and 12-yr-old children attending primary schools in Brisbane was undertaken in November/December 1983. Children from high socioeconomic level (SEL) schools exhibited lower dmft and DMFT scores at all ages. At age 6 yr the proportion of children with caries-free primary dentitions was for high SEL Schools 70%, for middle SEL schools 52% and for low SEL Schools 23%. At 12 yr DMFT scores were 1.8 (high), 2.1 (middle) and 3.3 (low). Similar differences in gingivitis prevalence occurred, children from high SEL schools displaying a much lower proportion of bleeding sites than those from middle and low SEL schools. For selection of children at "high risk" to gingival disease for intensive prevention programmes, an increased emphasis on probing techniques is indicated to achieve diagnostic consistency.  相似文献   
84.
Responding to a preceding article by Michael J. Newton ("Moral dilemmas in surgical training: intent and the case for ethical ambiguity"), Downie comments on three of Newton's themes. He agrees that trainees should engage in ethical self-appraisal but cautions that introspection is inappropriate at the time of an operation. Regarding Newton's downplaying of philosophical analysis in medical ethics, Downie agrees that there are limitations to the philosophical approach but contends that it can serve a very worthwhile function in helping doctors deal with ethical uncertainties. Finally, Downie perceives ambiguities in Newton's emphasis on the central importance of "ethical intent," which rejects the idea of ethical standards while urging individuals to take "personal responsibility" for their actions.  相似文献   
85.
Alcohol consumption and many alcohol-related problems have increased in most industrialized countries in the postwar period. The main societal responses have been increases in the treatment response to alcohol problems and in public and school education efforts. In the present era of fiscal crisis, there is also a trend toward punitive controls of the individual drinker. Potential policy alternatives should be broadened to include environmental protections for and from drunkenness, and a reconsideration of alcohol control strategies. Recent studies have shown that in some circumstances such laws have strong effects.Revised from a paper presented at a Plenary Session on Alcohol and Public Policy at the 28th International Institute on the Prevention and Treatment of Alcoholism, Munich, West Germany, July 9, 1982. Preparation of this article was supported by NIAAA National Alcohol Research Center grant (AA-05595) to the Alcohol Research Group, Institute of Epidemiology and Behavioral Medicine, Medical Research Institute of San Francisco, 1816 Scenic Ave., Berkeley, CA 94709.  相似文献   
86.
Increasing prevalence of mental health disorders within the Australian population is a serious public health issue. Adequate intake of fruits and vegetables (FV), dietary fibre (DF) and resistant starch (RS) is associated with better mental and physical health. Few longitudinal studies exist exploring the temporal relationship. Using a validated food frequency questionnaire, we examined baseline FV intakes of 5845 Australian adults from the AusDiab study and estimated food group-derived DF and RS using data from the literature. Perceived mental health was assessed at baseline and 5 year follow up using SF-36 mental component summary scores (MCS). We conducted baseline cross-sectional analysis and prospective analysis of baseline dietary intake with perceived mental health at 5 years. Higher baseline FV and FV-derived DF and RS intakes were associated with better 5 year MCS (p < 0.001). A higher FV intake (754 g/d vs. 251 g/d, Q4 vs. Q1) at baseline had 41% lower odds (OR = 0.59: 95% CI 0.46–0.75) of MCS below population average (<47) at 5 year follow up. Findings were similar for FV-derived DF and RS. An inverse association was observed with discretionary food-derived DF and RS. This demonstrates the association between higher intakes of FV and FV-derived DF and RS with better 5 year mental health outcomes. Further RCTs are necessary to understand mechanisms that underlie this association including elucidation of causal effects.  相似文献   
87.
Objectives

Despite the obstacles of limited education and employment opportunities—and the stress associated with immigration and pregnancy—Mexican immigrant women have low rates of preterm birth (PTB) compared to the US national average for all races and ethnicities. Stressors during pregnancy, and stressors associated with acculturation, may accelerate cellular aging manifested by shortened telomere length (TL) in pregnant women. Our objectives were to: (1) determine whether women with PTBs had shorter telomere lengths compared to women who had full term births; (2) assess the association of acculturation with TL and PTB.

Methods

This prospective pilot study collected data from 100 self-identified Mexican-origin pregnant women. Survey data included self-administered sociodemographic and acculturation measures and was collected from participants via paper and pen, while biologic data was collected via a single blood draw during a regularly scheduled prenatal visit between 26 and 36 weeks gestation. PTB data was collected from the participant’s medical record after delivery.

Results

TL was significantly associated with PTB; the median TL of the women with PTB was less than the median TL for the full sample (p?=?0.02). Based on regression analysis for PTB vs acculturation, we found no significant associations between acculturation and PTB or TL.

Conclusions for Practice

This study provides important evidence of the association between shortened maternal TL and adverse birth outcomes. By linking social, clinical and biologic data, we can enhance our understanding of social determinants that may affect racial and ethnic disparities in preterm birth.

  相似文献   
88.
Chen  Yao  Zhong  Qinyi  Luo  Jiaxin  Tang  Yujia  Li  Mingshu  Lin  Qian  Willey  James Allen  Chen  Jyu-Lin  Whittemore  Robin  Guo  Jia 《Prevention science》2022,23(7):1156-1168
Prevention Science - This study aimed to evaluate the efficacy of an intensive lifestyle modification program tailored to rural Chinese women with prior gestational diabetes mellitus compared with...  相似文献   
89.
BackgroundIn counseling patients about the complications of revision total hip arthroplasty (revTHA), it is imperative that mortality be considered. The actual mortality rate by indication of revision is ill-defined. The purpose of this study is to determine the mortality rate after revTHA.MethodsAn institutional database identified 596 patients who had undergone revTHA between 2012 and 2018. Medical records, national, state, and local death indexes were queried for mortality status and indication for revTHA. For survivors, the last clinical visit date was used for censoring in the mortality analysis. Mortality rates were calculated for all clinical patients and then by specific indication for revision.ResultsThe overall 2-year mortality rate following revTHA was 19.5 deaths per 1000 or 1 in 51 patients. Patients presenting with a periprosthetic fracture had a significantly higher 2-year mortality rate of 74.5 deaths per 1000 or 1 in 13 patients (P < .001), while an indication of dislocation or instability had a slightly higher 2-year mortality rate of 50.3 per 1000 (1 in 20) but this difference was not significant (P = .531). Other indications such as mechanical loosening or infection did not have a significantly different mortality rate.ConclusionThe overall 2-year mortality rate following revTHA was 19.5 deaths per 1000 which was largely attributed to patients with a periprosthetic fracture (74.5 per 1000) with other indications not significantly impacting mortality. Mortality rates and specific rates by indication for revision should be considered when counseling patients prior to revTHA.  相似文献   
90.
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