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71.
Under radiation protection legislation in the UK, employers have a duty to maintain appropriate records to account for radioactive materials in their possession and to ensure security of these materials. This applies to radioactive packages, containing items such as technetium generators, which are regularly delivered to hospital nuclear medicine departments. It also applies to the collection of packages, such as those containing used generators for return to the supplier. This article has been written by the professional bodies representing nuclear medicine in the UK in order to provide guidance to hospitals on appropriate procedures that will comply with the legislation. General principles, which should be met by any acceptable protocol, are stated, and practical guidance on how these may be implemented is given. Some example scenarios are outlined.  相似文献   
72.
Predictors of Breastfeeding Intention Among Low-Income Women   总被引:2,自引:0,他引:2  
OBJECTIVE: Breastfeeding rates are below the Healthy People 2010 goals despite recognized benefits of breastfeeding. This study determined factors that predict breastfeeding initiation among low-income pregnant women. METHODS: A self-administered closed-ended questionnaire was introduced to 694 pregnant women who were certified for WIC in Mississippi. The questionnaire collected data about demographics, breastfeeding intention, breastfeeding knowledge, self-efficacy, and three recognized barriers to breastfeeding: embarrassment, time and social constraints, and lack of social support. RESULTS: In bivariate analysis, women who intended to breastfeed were more often white and had at least some college education, higher income, a smaller family size, fewer children, and previous breastfeeding experience than women who did not intend to breastfeed. Intenders had higher levels of breastfeeding knowledge and self-efficacy and reported fewer barriers to breastfeeding than nonintenders. In multivariate logistic regression, fewer children, past breastfeeding experience, breastfeeding knowledge, self-efficacy, and perceived social support were independent predictors of breastfeeding intention. CONCLUSIONS: Women at high risk for not wanting to breastfeed can be identified for additional support. Interventions should focus on improving breastfeeding knowledge, enhancing confidence in one's ability to breastfeed, and overcoming barriers to breastfeeding, especially lack of social support, among low-income women.  相似文献   
73.
74.
Olfactory panic attacks have not been systematically assessed in a psychiatric population by any previous studies. Among Cambodian refugees attending a psychiatric clinic, the present investigation determines the following: (a) 1-month current prevalence of olfactory-triggered panic attacks, (b) associated psychopathology (Hopkins Symptom Checklist and the Structured Clinical Interview for DSM-IV-diagnosed posttraumatic stress disorder [PTSD]), and (c) frequency in events of olfactory panic of catastrophic cognitions (Panic Attack Cognitions Scale [PACQ]) and flashbacks (Clinician-Administered PTSD flashback scale). Forty-five percent of 100 consecutive psychiatric patients were found to have suffered an olfactory-triggered panic attack in the previous month; having current olfactory panic attacks was highly correlated with psychopathology (e.g., to PTSD diagnosis: and chi(2)=50.0; df=1; p<.001); and during olfactory-triggered panic attacks, catastrophic cognitions and flashbacks were common. Possible mechanisms for generation of high rates of olfactory-triggered panic attacks in this population are discussed (the "traumatic memory/catastrophic cognitions/interoceptive conditioning/escalating arousal" or "TCIE" model of panic generation) as are treatment implications.  相似文献   
75.
One hundred Khmer refugees attending a psychiatric clinic were surveyed to determine the prevalence of olfactory-triggered panic attacks as well as certain characteristics of the episodes, including trigger (i.e. type of odor), frequency, length, somatic symptoms, and the rate of associated flashbacks and catastrophic cognitions. Forty-five of the 100 patients had experienced an olfactory-triggered panic attack in the last month. Trauma associations and catastrophic cognitions (e.g. fears of a 'wind attack', 'weakness', and 'weak heart') were common during events of olfactory panic. Several case examples are presented. A multifactorial model of the generation of olfactory panic is adduced. The therapeutic implications of this model for the treatment of olfactory panic are discussed.  相似文献   
76.
77.
We investigated the effects of aflatoxin B1 (AFB1) on isolated splenic lymphocytes and the histo-morphologic changes in the spleens and liver of Fisher-344 male rats. Weaned animals were fed chow diets that contained 0, 0.01, 0.04, 0.4, or 1.6 ppm AFB1, using an intermittent dosing regimen (4 weeks on and 4 weeks off AFB1), for 40 weeks. An additional group of animals was fed the 1.6 ppm AFB1 diet continuously. The intermittent dosing regimen was designed to evaluate effects of cumulative dose and exposure for risk assessment comparisons. The percentages of T and B cells were affected as shown by flow cytometric analysis after the dosing cycles. The observed changes appeared to reverse or compensate to some extent after the off cycles. Lymphocytes were stimulated in culture for analysis of the production of IL-2, IL-1, and IL-6. Significantly increased production of IL-1 and IL-6 was seen in the second dosing cycle (12 weeks) and the second "off" cycle (16 weeks) at the higher doses. Inflammatory infiltrates were seen in the liver after eight weeks of continuous and intermittent dosing and were increased in size and number at 12 weeks in both 1.6 ppm dose groups correlating with the peak production of Il-1 and IL-6. We concluded that AFB1 effects on the immune system can be either stimulatory or suppressive dependent on a critical exposure window of dose and time. Immune cells in spleen such as T-lymphocytes and macrophages, both important mediators of inflammatory responses to tissue damage, were affected differently in the continuous and intermittent exposures to AFB1.  相似文献   
78.
The role of apoptosis in acetaminophen (AAP)-induced hepatic injury was investigated. Six hours after AAP administration to BALB/c mice, a significant loss of hepatic mitochondrial cytochrome c was observed that was similar in extent to the loss observed after in vivo activation of CD95 by antibody treatment. AAP-induced loss of mitochondrial cytochrome c coincided with the appearance in the cytosol of a fragment corresponding to truncated Bid (tBid). At the same time, tBid became detectable in the mitochondrial fraction, and concomitantly, Bax was found translocated to mitochondria. However, AAP failed to activate the execution caspases 3 and 7 as evidenced by a lack of procaspase processing and the absence of an increase in caspase-3-like activity. In contrast, the administration of the pan-inhibitor of caspases, benzyloxycarbonyl-Val-Ala-DL-Asp-fluoromethylketone (but not its analogue benzyloxycarbonyl-Phe-Ala-fluoromethylketone) prevented the development of liver injury by AAP and the appearance of apoptotic parenchymal cells. This correlated with the inhibition of the processing of Bid to tBid. The caspase inhibitor failed to prevent both the redistribution of Bax to the mitochondria and the loss of cytochrome c. In conclusion, apoptosis is an important causal event in the initiation of the hepatic injury inflicted by AAP. However, as suggested by the lack of activation of the main execution caspases, apoptosis is not properly executed and degenerates into necrosis.  相似文献   
79.
BACKGROUND: Approximately 2.5 million Americans are admitted to the hospital after traumatic physical injury each year. Few investigations have elicited patients' perspectives regarding posttraumatic outcomes. OBJECTIVE: To identify and categorize physically injured trauma survivors' posttraumatic concerns. RESEARCH DESIGN: Prospective longitudinal investigation; trauma survivors were interviewed during the post-injury hospitalization and again 1, 4, and 12 months after the trauma. SUBJECTS: Ninety-seven, randomly selected, English speaking, hospitalized survivors of motor vehicle-crashes or assaults. MEASURES: At the end of each interview patients were asked, "Of all the things that have happened to you since you were injured, what concerns you the most?" Using an iterative process and working by consensus, investigators categorized patient concerns in content domains. Concern domains were then compared with established measures of posttraumatic stress disorder (PTSD) symptoms and limitations in physical functioning. RESULTS: Seven categories of posttraumatic concerns were identified. During the course of the year, 73% of patients expressed physical health concerns, 58% psychological concerns, 53% work and finance concerns, 40% social concerns, 10% legal concerns, 10% medical concerns, and 20% uncodable concerns. Rater agreement on concern categorization was substantial (kappa = 0.72). The mean number of concerns expressed per patient gradually decreased over time (1 month mean = 1.51; 12 month mean = 1.26) and resembled the trajectories of PTSD symptoms and functional limitations. CONCLUSIONS: The concerns of physically injured trauma survivors are readily elicited and followed up during the course of the year after injury. Open-ended inquiry regarding posttraumatic concerns may complement standardized outcome assessments by identifying and contextualizing the outcomes of greatest importance to patients.  相似文献   
80.
Surveying 60 Vietnamese patients with either current or past post-traumatic stress disorder, this article aims to phenomenologically characterize the syndrome of 'hit by the wind' in a multidimensional manner. This includes determining the patient conceptualization of the disorder, profiling 'hit by the wind' episodes suffered by patients in the previous month, and presenting case vignettes. Eighteen of the 60 patients (30%) suffered at least one episode of 'hit by the wind' in the last month; all 18 patients had at least one episode of 'hit by the wind' in the last month that met panic attack criteria. For the 18 patients, 33 episodes of'hit by the wind' that met panic attack criteria were experienced in the previous month. For these 33 episodes, the most frequently reported DSM-IV panic attack symptoms were chills (100%; 33/33) and dizziness (88%; 29/33). Flashbacks played a role in the 'hit by the wind' episodes for 5 of the 18 patients (28%). In the discussion, a model of how the syndrome of 'hit by the wind' generates panic is adduced; also, possible Chinese origins of the disorder are discussed.  相似文献   
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