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991.
Povidone–iodine (PVP-I) has been widely used as an antiseptic agent during invasive procedures for prenatal diagnosis. Women have been reported of thyroid dysfunction after simple exposure to PVP-I. We studied the effect on thyroid function and urinary iodine excretion after a single topical application of PVP-I in 31 women who had a miscarriage during the first trimester of pregnancy. PVP-I is absorbed through the skin and the vaginal mucosa, resulting in a sudden increase in the urinary excretion of iodine and a short-term variation in concentrations of thyroid hormones in maternal serum. This metabolic effect could have consequences for the embryo and the fetus during crucial stages of development.  相似文献   
992.
993.
Context: Relatively little is known about the factors shaping public attitudes toward obesity as a policy concern. This study examines whether individuals' beliefs about the causes of obesity affect their support for policies aimed at stemming obesity rates. This article identifies a unique role of metaphor-based beliefs, as distinct from conventional political attitudes, in explaining support for obesity policies.
Methods: This article used the Yale Rudd Center Public Opinion on Obesity Survey, a nationally representative web sample surveyed from the Knowledge Networks panel in 2006/07 (N = 1,009). The study examines how respondents' demographic and health characteristics, political attitudes, and agreement with seven obesity metaphors affect support for sixteen policies to reduce obesity rates.
Findings: Including obesity metaphors in regression models helps explain public support for policies to curb obesity beyond levels attributable solely to demographic, health, and political characteristics. The metaphors that people use to understand rising obesity rates are strong predictors of support for public policy, and their influence varies across different types of policy interventions.
Conclusions: Over the last five years, the United States has begun to grapple with the implications of dramatically escalating rates of obesity. Individuals use metaphors to better understand increasing rates of obesity, and obesity metaphors are independent and powerful predictors of support for public policies to curb obesity. Metaphorical reasoning also offers a potential framework for using strategic issue framing to shift support for obesity policies.  相似文献   
994.
虫牙药的化学成分研究   总被引:6,自引:0,他引:6  
从广西产的虫牙药Isodon ternifolius (D.Don) Kudo的乙酸乙酯提取物中分离到9个单体成分,经鉴定其中两个为新的二萜化合物,命名为牛尾草甲素、乙素(isodoternifolinA,B),光谱数据分析和化学反应证明,甲素的结构为6β,11α,15β-triacetoxy-7β-hydroxy-7α,20-epoxy-entkaur-16-ene,乙素的结构为11αacetoxy-6β,7β.15β-trihydroxy-7α,20-epoxy-entkaur-16-ene。其它成分分别鉴定为β-谷甾醇(β-sitosterol),乌苏酸(ursolicacid),齐墩果酸(oleanolicacid),胡萝β甙(β-sitosterol-β-D-glucopyranoside),6-甲基-三十二烷烃(6-methyldotriacontane),细叶香茶菜甲素(sodoponin)和细叶香茶菜乙素(ternifolin),其中6-甲基-三十二烷烃是首次从香茶菜属植物中分得。  相似文献   
995.
Magnetic resonance (MR) imaging was used as a follow-up technique in 60 patients who underwent surgery and/or radiation therapy for primary malignant musculoskeletal tumors. MR imaging was performed on a 1.5-T imager with T1- and T2-weighted imaging sequences; MR imaging findings were confirmed by means of posttreatment surgery and histologic analysis or follow-up for at least 1 year. If a low-signal-intensity lesion was seen on T2-weighted images in a patient who had undergone radiation therapy or surgery, the patient usually did not have active tumor (sensitivity, 96%). If a high-signal-intensity lesion was seen after a patient had undergone only surgery, the patient had active tumor (six of six such cases). In patients who had undergone only radiation therapy, however, the presence of a high-signal-intensity lesion may indicate either active tumor or radiation-induced inflammatory changes. Thus, in such cases, differential diagnosis of active tumor may be difficult, if not impossible, to make from MR images.  相似文献   
996.
Weinstein  MJ; Fulcher  CA; Chute  LE; Zimmerman  TS 《Blood》1983,62(5):1114-1117
We have compared apparent molecular weights of purified factor VIII procoagulant protein (VIII:C) and VIII:C antigen (VIII:CAg) by two different NaDodSO4 gel electrophoretic techniques. In a discontinuous NaDodSO4-7.5% polyacrylamide system, reduced and unreduced VIII:C, purified from commercial factor VIII concentrates by a monoclonal antibody immunoadsorption technique, showed a major doublet at mol wt 0.79 and 0.8 X 10(5) and less intense bands extending up to 1.9 X 10(5). In NaDodSO4-4% polyacrylamide/0.5% agarose gels (NaDodSO4-4% PAAGE), purified VIII:C had a major band of mol wt 1.0 X 10(5), with minor bands of mol wt 0.96, 1.1, 1.4, 1.6, 1.8, 2.2, and 2.4 X 10(5). In NaDodSO4-4% PAAGE of 125I-anti-VIII:C-Fab-VIII:CAg complexes, the major and minor forms of VIII:CAg in purified VIII:C had the same molecular weight as above when calculated by subtracting the molecular weight of 125I-Fab from 125I-Fab-VIII:CAg. In both plasma and factor VIII concentrate, a band of mol wt 2.4 X 10(5) predominated, and minor VIII:CAg forms of mol wt 2.6, 1.8, 1.2 and 1.0 X 10(5) were also visible. We conclude that the molecular weight of plasma VIII:CAg forms agree with those derived from protein stains of purified VIII:C in the NaDodSO4-4% PAAGE system, but that consistently lower molecular weight values are obtained for purified VIII:C in the discontinuous system. Both native and either disaggregated or proteolyzed VIII:C species are present in the purified VIII:C preparation.  相似文献   
997.
Breast cancer: PET imaging of estrogen receptors   总被引:14,自引:0,他引:14  
Thirteen patients with primary breast masses were studied with positron emission tomography (PET) and 16 alpha-[fluorine-18]-fluoroestradiol-17 beta. PET images demonstrated uptake of the labeled estrogen analog at sites of primary carcinomas and in several foci of axillary lymph node metastases, as well as in one distant metastatic site. There was excellent correlation between uptake within the primary tumor measured on the PET images and the tumor estrogen-receptor concentration measured in vitro after excision (r = .96). This technique may provide an in vivo method of assessing estrogen receptors in primary and metastatic breast cancers and thus guide management of this disease with antiestrogen chemotherapy.  相似文献   
998.

Background and purpose:

Cyclooxygenase inhibitors function to reduce levels of prostaglandin E2 (PGE2) and are broadly efficacious in models of bladder overactivity. We therefore investigated a regulation of urinary bladder function in conscious rats by modulation of the EP3 receptor for PGE2.

Experimental approach:

The activity of the EP3 receptor agonist GR63799X, and EP3 receptor antagonists, CM9 and DG041, at recombinant EP3 receptors was evaluated in vitro. In vivo, intraduodenal dosing during conscious, continuous-filling cystometry of spontaneously hypertensive rats was utilized to determine the urodynamic effect of EP3 receptor modulation.

Key results:

GR63799X dose-dependently (0.001–1 mg·kg−1) reduced bladder capacity, as indicated by a reduction in both the micturition interval and volume of urine per void. In contrast, CM9 (10 and 30 mg·kg−1) and DG041 (30 mg·kg−1) enhanced bladder capacity, as indicated by significantly longer micturition intervals and larger void volumes. CM9 and DG041 inhibited the responses to GR63799X supporting the in vivo activity of these pharmacological agents at the EP3 receptor. In addition to its effect on bladder capacity, GR63799X increased endogenous urine production. Intra-arterial infusion of saline mimicked the enhancement of urine flow observed with GR63799X, and the response was inhibited by CM9.

Conclusions and implications:

These data support the EP3 receptor as a modulator of urinary bladder activity in the conscious rat, and in addition, indicate a role for EP3 receptor activity in regulating urine flow.  相似文献   
999.
Abstract:  Musculoskeletal problems have become a significant issue for the profession of dentistry and dental hygiene. This review provides a detailed examination and discussion regarding the prevalence of musculoskeletal disorders (MSD) in dental personnel and possible causative factors. All research studies or literature reviews, which have reported on the prevalence of musculoskeletal symptoms and/or potential risk factors for this problem in dentists, dental hygienists and dental students, were selected for inclusion. Our literature suggests that the prevalence of general musculoskeletal pain ranges between 64% and 93%. The most prevalent regions for pain in dentists have been shown to be the back (36.3–60.1%) and neck (19.8–85%), while the hand and wrist regions were the most prevalent regions for dental hygienists (60–69.5%). Interestingly, we found that studies on MSDs among dental and dental hygiene students are quite limited. Many risk factors have been identified, including static and awkward posture and work practices. Overall, the review suggests that musculoskeletal problems represent a significant burden for the dental profession. More research in the form of larger studies is urgently required, to help more clearly elucidate the development of this important issue for dental hygienists and dental hygiene students.  相似文献   
1000.
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