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Background: Lay belief systems about the malleability of human attributes have been shown to impact behavior change in multiple domains. Addiction mindset—i.e., beliefs about the permanence (vs. malleability) of addiction — may affect cigarette smokers’ ability to quit, but this has never been examined. Objectives: The aims of the present research were to develop a measure of addiction mindset (study 1) and examine its associations with various psychological aspects of quitting smoking (study 2). Methods: In Study 1, using factor analysis of current smokers’ and nonsmokers’ (n?=?600) responses to 22 items designed to measure addiction mindset, we developed a reliable six-item Addiction Mindset Scale (AMS). In Study 2, adult smokers (n?=?200) completed the AMS, and measures of a number of psychological processes related to smoking. Results: Higher scores on the AMS, indicative of the belief that addiction is malleable (referred to as a growth mindset), were positively and significantly associated with greater motivation to quit, greater commitment to quitting, greater self-efficacy to abstain, less attribution of failure to lack of ability to change addiction, and fewer self-reported barriers to cessation (all p’s < .05). Conclusions: The results of this study show a relationship between the beliefs about the permanence of addiction and psychological processes relevant to quitting smoking. The findings underscore the potential of future research exploring how addiction mindsets relate to successful smoking cessation as well as other types of addictive behavior and how they can be applied to change people’s behavior.  相似文献   
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Studies on the development of imaging agents for targeting neuroreceptors is an area of considerable interest owing to the limited availability of specific as well as selective radiolabeled agents. Therefore, with an aim of developing a receptor-specific agent, iminodiacetic acid (IDA) derivative of 5-hydroxy tryptamine viz., HTIDA has been synthesized. HTIDA could be radiolabeled with the synthon [(99m)Tc(CO)(3)(H(2)O)(3)](+) in >98% yield. The biodistribution studies in normal Swiss mice showed that the (99m)Tc(CO)(3)-HTIDA crosses the blood-brain barrier successfully with a brain uptake of 0.5%ID/g at 5min post injection. The other relevant observations from biodistribution studies included no significant uptake in any other organ and fast clearance from blood, lungs and liver.  相似文献   
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Gallstones are common and their incidence increases with age.1 Fifty per cent of these stones are in the common bile duct (CBD) in the elderly.2 Most of them are silent but with time there is an increasing chance of developing symptoms which are more likely to be serious in the elderly.3 Failure to relieve mechanical obstruction of bile flow may lead to secondary biliary cirrhosis.4 It has been estimated that on average secondary biliary cirrhosis develops some seven years after the onset of obstruction from a stricture, four and half years after gallstone obstruction and 10 months after the onset of malignant stricture.5 The characteristic features are the pathological findings of portal-portal linkages, with a pattern of monolobular cirrhosis and the preservation of normal vascular relationships.6 Secondary biliary cirrhosis may lead to hepatic insufficiency and portal hypertension with the resultant complications, such as bleeding oesophageal varices, hypersplenism with pancytopenia, ascites and encephalopathy. We describe a patient in whom the diagnosis was not suspected until laparotomy and confirmed only at autopsy.  相似文献   
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Reporter probe 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) and reporter gene mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) have been used for imaging reporter gene expression with PET. Current methods for quantitating the images using the percentage injected dose per gram of tissue do not distinguish between the effects of probe transport and subsequent phosphorylation. We therefore investigated tracer kinetic models for 18F-FHBG dynamic microPET data and noninvasive methods for determining blood time-activity curves in an adenoviral gene delivery model in mice. METHODS: 18F-FHBG (approximately 7.4 MBq [approximately 200 microCi]) was injected into 4 mice; 18F-FHBG concentrations in plasma and whole blood were measured from mouse heart left ventricle (LV) direct sampling. Replication-incompetent adenovirus (0-2 x 10(9) plaque-forming units) with the E1 region deleted (n = 8) or replaced by HSV1-sr39tk (n = 18) was tail-vein injected into mice. Mice were dynamically scanned using microPET (approximately 7.4 MBq [approximately 200 microCi] 18F-FHBG) over 1 h; regions of interest were drawn on images of the heart and liver. Serial whole blood 18F-FHBG concentrations were measured in 6 of the mice by LV sampling, and 1 least-squares ratio of the heart image to the LV time-activity curve was calculated for all 6 mice. For 2 control mice and 9 mice expressing HSV1-sr39tk, heart image (input function) and liver image time-activity curves (tissue curves) were fit to 2- and 3-compartment models using Levenberg-Marquardt nonlinear regression. The models were compared using an F statistic. HSV1-sr39TK enzyme activity was determined from liver samples and compared with model parameter estimates. For another 3 control mice and 6 HSV1-sr39TK-positive mice, the model-predicted relative percentage of metabolites was compared with high-performance liquid chromatography analysis. RESULTS: The ratio of 18F-FHBG in plasma to whole blood was 0.84 +/- 0.05 (mean +/- SE) by 30 s after injection. The least-squares ratio of the heart image time-activity curve to the LV time-activity curve was 0.83 +/- 0.02, consistent with the recovery coefficient for the partial-volume effect (0.81) based on independent measures of heart geometry. A 3-compartment model best described 18F-FHBG kinetics in mice expressing HSV1-sr39tk in the liver; a 2-compartment model best described the kinetics in control mice. The 3-compartment model parameter, k3, correlated well with the HSV1-sr39TK enzyme activity (r2 = 0.88). CONCLUSION: 18F-FHBG equilibrates rapidly between plasma and whole blood in mice. Heart image time-activity curves corrected for partial-volume effects well approximate LV time-activity curves and can be used as input functions for 2- and 3-compartment models. The model parameter k3 from the 3-compartment model can be used as a noninvasive estimate for HSV1-sr39TK reporter protein activity and can predict the relative percentage of metabolites.  相似文献   
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Several parallels exist between preeclampsia and atherosclerosis. Both are multifactorial diseases that share risk factors such as obesity, insulin resistance, lipid abnormalities, and elevated serum homocysteine. There are also similarities in the biochemical changes seen in both diseases, including elevated serum triglycerides, decreased HDL cholesterol and enhanced formation of small, dense LDL particles as well as vascular atherosclerotic lesions. Chronic infection with Chlamydia pneumoniae has been linked to coronary artery disease. This study evaluated a possible link between the incidence of preeclampsia and infection with C. pneumoniae by examining the rate of seropositivity in 81 women with preeclampsia, and 206 women with normal pregnancies. Although our data confirmed well-known risk factors for preeclampsia such as obesity, diabetes, and hypertension, we found no difference in the rate of seropositivity between preeclampsia and normal pregnancy. On the contrary, the presence of chlamydial antibodies was lower in preeclampsia. Multiparous women with preeclampsia showed a significantly lower rate of seropositivity than multiparous normal women and nulliparous preeclamptics. In addition, women with a history of preeclampsia who developed preeclampsia in the current pregnancy also had a significantly lower rate of seropositivity.  相似文献   
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Mice were fed for 24 weeks with three different subtoxic dosages of γ-HCH (0.012, 0.12 and 1.2 mg/kg) mixed in powdered feed. The immunological profile was assessed at an interval of one month during the entire exposure period. Both the cell mediated and humoral components of immunity showed a biphasic response characterized initially by stimulation followed by suppression in a dose dependent manner. However, γ-HCH did not affect the functional properties of peritoneal macrophages. Histological changes in lymphoid organs were in accordance with the biphasic immunomodulatory effects of γ -HCH.  相似文献   
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We present two children with massive bleeding into the serous body cavities accompanied by intractable consumption coagulopathy. One had a large spleen palpable at admission, the other developed progressive splenomegaly while in hospital. Neither child had any external evidence of angiomatous lesions. A splenic hemangioma was suspected clinically and on abdominal ultrasound; the diagnosis was confirmed at laparotomy. Splenectomy resulted in a prompt cure in both cases.  相似文献   
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