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31.
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Cuprous chloride and copper powder (in acid media) initiate the aqueous polymerization of certain vinyl monomers such as methyl methacrylate, ethyl methacrylate, methacrylic acid and styrene but it fails in case of acrylonitrile, methyl acrylate, and acrylic acid under identical conditions. Catalyst exponent of this initiator (in acid aqueous media) with respect to methyl methacrylate is 0.38. Quantitative determination of end-groups by dye techniques of the polymers obtained shows that about 2 hydroxyl end-groups per chain are present under acidic conditions in presence of slight traces of oxygen but in rigorous absence of oxygen, very little OH end-groups are found incorporated. The mechanism of initiation under different experimental condition is discussed.  相似文献   
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We analyzed patterns of antibody response to recombinant transactivator protein (human Immunodeficiency virus type 1 [HIV-1] tat) in serum samples from HIV-1-negative subjects (n = 60), HIV-1-infected asymptomatic patients (n = 20), HIV-1-infected patients with Kaposi's sarcoma (n = 25), and patients with Kaposi's sarcoma without HIV-1 infection. None of the healthy subjects possessed anti-tat immunoglobulin G (IgG) in their serum. All asymptomatic patients with HIV-1 infection were anti-tat IgG-positive. Epitope mapping revealed that these sera had anti-tat IgG to all the functional domains of tat protein. Histochemical studies on lymph nodes from five asymptomatic HIV-1-infected patients showed that, in all cases, tat-positive cells were present within the germinal center at the stage of follicular fragmentation containing immunoblasts and small lymphocytes. Of the 25 HIV-1-infected patients with Kaposi's sarcoma, 4 were anti-tat IgG-positive; however, the epitope analysis revealed that IgG to functional domains of tat protein--in particular to transactivating response element (TAR)-binding site--were absent. All patients with Kaposi's sarcoma without HIV-1 infection were anti-tat IgG-negative. Presence or absence of anti-tat IgG and a prevalence of different antibody profiles in different groups of patients indicated the pathophysiologic role of tat protein. Thus, a passive immunization with anti-tat IgG could be a useful strategy to influence the pathophysiologic state of the disease.  相似文献   
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M Leone  V Chandra  B S Schoenberg 《Neurology》1987,37(8):1339-1343
Mortality rates for deaths "due to" and "with" motor neuron disease are presented for the first time. Age-specific mortality rates increase with age until 70 to 74 years and then decline. There appear to be no major differences by race in the age-adjusted mortality rates, but these rates are higher for males both white and nonwhite. A case-control study of all deaths with amyotrophic lateral sclerosis (ALS) was conducted for deaths due to ALS in the year 1971. Conditions associated with ALS at the time of death include pneumonia and bronchopneumonia, symptoms referable to respiratory system, superficial injury to shoulder and upper arm, essential benign hypertension, chronic skin ulcer, and malnutrition. No association was found between ALS and malignancies, Parkinson's disease, or dementia.  相似文献   
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An ophthalmic evaluation was undertaken in 250 consecutive cases of mental retardation where no specific etiological diagnosis could be established, ie, "idiopathic" mental retardation. Visual impairment was noted in 59 of these patients, and was mainly due to primary optic atrophy, besides cortical blindness, strabismus, nystagmoid eye movements, refractive errors and various associated congenital ocular anomalies. It was encouraging to find that 191 children had active vision, including 10 patients with definite disc pallor. The importance of useful vision in these retarded children cannot be overemphasized. This is probably the first report in the literature analyzing the ocular changes and their significance in a fairly large series of idiopathic mental retardation.  相似文献   
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Obesity and other diet-related health conditions have received much attention in the public health literature over the past two decades. This study investigates the relationship between household food budget shares at different food outlets with diet quality and weight-related health outcomes in the United States. Our analysis used event-level food purchase data from the national household food acquisition and purchases survey (FoodAPS). We find that, after controlling for observables, food purchase location is significantly associated with diet quality and body mass index (BMI). Our findings indicate that larger food budget shares at convenience stores and restaurants are linked with poor diet quality based on the healthy eating index-2015 (HEI-2015) scores and higher BMI. We further explored potential heterogeneity on outcomes of interest across income groups. Results suggest heterogeneous effects may exist across income groups: low-income households, who spent a larger share of their food budget at convenience stores and fast-food restaurants are related to poor diet quality and more likely to be obese. Our findings will help improve understanding of the causes of diet-related health problems and may illuminate potential avenues of intervention to address obesity.  相似文献   
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Background:Urosepsis is a recognized complication of transrectal ultrasound-guided prostate biopsy (TRUS-Bx). Pre-biopsy rectal swabs have been used to identify patients with microorganisms in the rectal flora resistant to the conventionally used empirical prophylaxis. The transperineal route of biopsy (TP-Bx) has a lower complication risk but comes at an increased cost.Materials and methods:Retrospective cohort study including patients undergoing prostate biopsies between October/2015 and April/2018. The intervention cohort, a rectal swab was performed, the result of which dictated the biopsy route; TRUS-Bx against TP-Bx. TP-Bx for patients with fluoroquinolone resistance or extended-spectrum β-lactamase. The control cohort underwent TRUS without a rectal swab receiving empirical antibiotics—oral ciprofloxacin and intravenous gentamicin.Results:Total 1000 patients were included in which 500 underwent a swab, 14 (2.8%) developed post-TRUS biopsy infective complications with 3 having positive bacteremia (0.6%); 500 had no swab, 47 (9.4%) developed post-TRUS biopsy infective complications with 22 (4.4%, p < 0.05) having positive bacteremia. Three patients (0.6%) of patients who underwent swab developed urinary tract infection symptoms whilst 12 (2.4%) had urinary tract infection in the control group. In those patients that underwent a swab, 14 required hospitalization with mean length of stay of 2.5 days versus 43 patients of the control with 3.6 days. Cost analysis concluded savings of this strategy was £18,711.Conclusions:We have demonstrated a protocol that reserves template biopsies for higher risk patients and can significantly reduce sepsis and other infectious complication rates whilst also proving to be a cost-efficient strategy. We recommend that units not utilizing rectal swabs to uncover the fluoroquinolone resistance rate by introducing them. We advocate units that already utilize rectal swabs, to introduce transperineal biopsy for their higher risk patients.  相似文献   
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A key recommendation of the National AIDS Control Programme‐IV of India was to develop new strategies for geo‐prioritization of the human immunodeficiency virus (HIV) epidemic. We conducted this study to categorize the districts in Maharashtra (India) based on a multidimensional framework for geo‐prioritization of services. Programmatic data on trends of HIV prevalence, coverage of marginalized populations and vulnerability factors were included. A composite indicator based on these was developed, and the cumulative score was calculated for each district. HIV prevalence among general population has declined steadily from 0.60% in 2007 to 0.33% in 2017. The programme coverage was stable but inadequate for men who have sex with men (MSM). The coverage for female sex workers (FSWs) was inadequate and reduced over time. Nine districts were categorized as high priority, 13 as moderate priority and 11 were classified as low‐priority districts based on burden and vulnerability for HIV. The high‐priority districts were Pune, Solapur and Yavatmal for FSW interventions and Pune, Thane and Latur for MSM interventions. This multidimensional indicator is based on existing programmatic data, dynamic and can be made state‐specific. It is useful to categorize and prioritize districts for allocation of resources and geo‐prioritization of services in resource limited settings.  相似文献   
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