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41.
Introduction and Aims . The aim of this study was to examine heroin careers among former users to assess desistance factors and explanations for sustained abstinence. Design and Methods . The study surveyed 107 former problematic heroin users who have achieved long‐term abstinence about their experiences of achieving and sustaining abstinence. The cohort was recruited opportunistically from three sources, drawing heavily on former users working in the addictions field. Results . On average, the group had heroin careers lasting for just under 10 years, punctuated by an average of 2.6 treatment episodes and 3.1 periods of abstinence, and had been heroin abstinent for an average of 10 years at the time of completing the survey. The most commonly expressed reason for finally achieving abstinence was ‘tired of the lifestyle followed by reasons relating to psychological health. In contrast, when asked to explain how abstinence was sustained, clients quoted both social network factors (moving away from drug‐using friends and support from non‐using friends) and practical factors (accommodation and employment) as well as religious or spiritual factors. Treatment was not mentioned widely either in achieving or sustaining abstinence, in contrast to 12‐Step, which was endorsed widely. Discussion and Conclusions . The study supports a careers perspective for examining heroin careers and indicates that, while achieving abstinence is possible for chronic opiate users, the path to sustained abstinence is complex and often reliant upon external support systems.  相似文献   
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Systemic therapy (chemotherapy or hormonal therapy) as an adjuvant to modalities of local control is now an integral part of the management of almost all patients with primary breast cancer metastatic to axillary lymph nodes. In addition, recent data suggest an expanding role for such treatments in patients without axillary involvement. Although some node-negative patients should probably not receive adjuvant therapy, the precise criteria to be used for selection are still under active discussion in the literature. Of the two types of systemic treatment, it is generally accepted that chemotherapy is indicated for premenopausal patients and that tamoxifen is useful for postmenopausal patients whose tumors contain estrogen or progesterone receptors. The recent analysis of several studies has suggested that chemotherapy may add to the benefits of tamoxifen in some postmenopausal patients as well. A possible role for tamoxifen in younger patients is being evaluated. For patients at relatively low risk of systemic relapse (i.e., those with zero to three involved axillary lymph nodes), no chemotherapy regimen has yet shown an advantage over 6 months of cyclophosphamide, methotrexate and 5-fluorouracil. For patients at high risk, however, doxorubicin-based regimens have demonstrated benefits. High-dose chemotherapies, some involving autologous bone marrow support, are being investigated for patients with ten or more involved nodes who are at very high risk of the eventual development of stage IV disease.  相似文献   
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BACKGROUND: Treatment of hemophilia patients with recombinant factor VIII concentrates has not previously been associated with anaphylaxis. STUDY DESIGN AND METHODS: A 5-week-old boy with severe hemophilia A developed dyspnea, cyanosis, hypotension, and a diffuse urticarial rash following treatment with a recombinant factor VIII (Recombinate). To identify the cause of anaphylaxis in this patient, the vial lot was examined for the presence of endotoxin, and a checkerboard immunoblotting technique was used to test serum and/or plasma samples from the patient and mother for the presence of antibodies (IgA, IgG, IgE, and IgM) to Recombinate-related antigens (recombinant factor VIII, von Willebrand factor, human serum albumin, Chinese hamster ovary proteins, bovine serum albumin, mouse monoclonal anti-human factor VIII, polyethylene glycol 3350), and to ethylene oxide, the agent used to sterilize the infusion equipment. RESULTS: No immune response directed against the Recombinate-related antigens or ethylene oxide that could be associated with the anaphylactic reaction was identified. Endotoxin was not present upon rabbit pyrogen testing of the therapeutic product. CONCLUSION: These studies failed to show any association between Recombinate and the onset of the allergic reaction. This seems to be the first reported case of anaphylaxis following the infusion of a recombinant form of factor VIII concentrate.  相似文献   
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目的调查内分泌门诊中糖尿病患者阴茎勃起功能障碍(ED)患病率,并评价西地那非(万艾可)在糖尿病合并ED患者中的疗效和安全性。方法多中心收集2型糖尿病男性患者6193例,入选6178例,患者签署知情同意书后,根据国际勃起功能指数表(IIEF5)患者进行自我评分。对3个月内服用3剂万艾可的患者除要求填写治疗前的IIEF5表评分外,还要求填写治疗后的总体疗效问题回答表,以评价万艾可治疗的疗效,并记录患者服药后的不良事件以评价其安全性。结果国内42家医院内分泌门诊2型糖尿病患者中ED的患病率为75.2%,其中重度、中度和轻度ED分别为9.1%、17.2%、48.9%。该受检人群中ED的知晓率为85.0%,但治疗率仅为9.4%。多因素回归分析显示患者年龄、糖尿病病程、血糖控制不佳(HbA1C>6.5%)与糖尿病患者ED的发生独立相关。共有389例患者服用万艾可治疗,治疗后患者IIEF5总评分和各问题的评分均显著高于治疗前(P<0.01);根据IIEF5评分,治疗后重、中度ED患者例数明显少于治疗前(P<0.01)。根据总体疗效评估问题的回答,给予万艾可治疗后勃起功能改善率达86.4%。对安全性评价显示服用万艾可后出现的与药物有关的不良事件主要是颜面潮红、头痛、心悸和口干等,大多为轻度。结论在2型糖尿病患者中ED是常见的合并症,万艾可治疗糖尿病合并ED疗效确切,并有良好的安全性。  相似文献   
47.
MyD88-deficient mice were previously shown to have increased susceptibility to Bacillus anthracis infection relative to wild-type animals. To determine the mechanism by which MyD88 protects against B. anthracis infection, knockout mice were challenged with nonencapsulated, toxigenic B. anthracis or with anthrax toxins. MyD88-deficient mice had increased susceptibility to B. anthracis and anthrax lethal toxin but not to edema toxin. Lethal toxin alone induced marked multifocal intestinal ulcers in the knockout animals, compromising the intestinal epithelial barrier. The resulting enteric bacterial leakage in the knockout animals led to peritonitis and septicemia. Focal ulcers and erosion were also found in MyD88-heterozygous control mice but with far lower incidence and severity. B. anthracis infection also induced a similar enteric bacterial septicemia in MyD88-deficient mice but not in heterozygous controls. We show that lethal toxin and B. anthracis challenge induce bacteremia as a result of intestinal damage in MyD88-deficient mice. These results suggest that loss of the intestinal epithelial barrier and enteric bacterial septicemia may contribute to sensitizing MyD88-deficient mice to B. anthracis and that MyD88 plays a protective role against lethal toxin-induced impairment of intestinal barrier.  相似文献   
48.
Bacillus anthracis is the causative agent of anthrax, and the tripartite anthrax toxin is an essential element of its pathogenesis. Edema factor (EF), a potent adenylyl cyclase, is one of the toxin components. In this work, anti-EF monoclonal antibodies (MAb) were produced following immunization of mice, and four of the antibodies were fully characterized. MAb 3F2 has an affinity of 388 pM, was most effective for EF detection, and appears to be the first antibody reported to neutralize EF by binding to the catalytic C(B) domain. MAb 7F10 shows potent neutralization of edema toxin activity in vitro and in vivo; it targets the N-terminal protective antigen binding domain. The four MAb react with three different domains of edema factor, and all were able to detect purified edema factor in Western blot analysis. None of the four MAb cross-reacted with the lethal factor toxin component. Three of the four MAb protected mice in both a systemic edema toxin challenge model and a subcutaneous spore-induced foreleg edema model. A combination of three of the MAb also significantly delayed the time to death in a third subcutaneous spore challenge model. This appears to be the first direct evidence that monoclonal antibody-mediated neutralization of EF alone is sufficient to delay anthrax disease progression.  相似文献   
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The effect of two chronic motor training paradigms on the ability of the lumbar spinal cord to perform an acute instrumental learning task was examined in neonatally (postnatal day 5; P5) spinal cord transected (i.e., spinal) rats. At approximately P30, rats began either unipedal hindlimb stand training (Stand-Tr; 20-25min/day, 5days/week), or bipedal hindlimb step training (Step-Tr; 20min/day; 5days/week) for 7 weeks. Non-trained spinal rats (Non-Tr) served as controls. After 7 weeks all groups were tested on the flexor-biased instrumental learning paradigm. We hypothesized that (1) Step-Tr rats would exhibit an increased capacity to learn the flexor-biased task relative to Non-Tr subjects, as locomotion involves repetitive training of the tibialis anterior (TA), the ankle flexor whose activation is important for successful instrumental learning, and (2) Stand-Tr rats would exhibit a deficit in acute motor learning, as unipedal training activates the ipsilateral ankle extensors, but not flexors. Results showed no differences in acute learning potential between Non-Tr and Step-Tr rats, while the Stand-Tr group showed a reduced capacity to learn the acute task. Further investigation of the Stand-Tr group showed that, while both the ipsilateral and contralateral hindlimbs were significantly impaired in their acute learning potential, the contralateral, untrained hindlimbs exhibited significantly greater learning deficits. These results suggest that different types of chronic peripheral input may have a significant impact on the ability to learn a novel motor task, and demonstrate the potential for experience-dependent plasticity in the spinal cord in the absence of supraspinal connectivity.  相似文献   
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