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31.
T H Fritts M J McCoid R L Haddock 《The American journal of tropical medicine and hygiene》1990,42(6):607-611
The brown tree snake, Boiga irregularis, is abundant on Guam and commonly invades human habitations. Data on emergency room visits on Guam document a high frequency of snakebites on Guam. Over 50% of the emergency room visits for snakebite involved children less than 4 years old. Records exist of 4 infants, 1, 2, 5, and 10 months old, who displayed significant symptoms after being bitten, while sleeping, by snakes. Two infants developed respiratory problems within a few hours and required medical treatment for asphyxiation. Lethargy, diminished sensory perceptions, drooping eyelids, swelling, discoloration, and bleb formation were variable in occurrence in the patients. 相似文献
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A large number of biologic, technological, and clinical studies await the development of procedures that will allow totipotent hematopoietic stem cells to be expanded in vitro. Previous work has suggested that hematopoiesis can be reconstituted using transplants of cells from long- term marrow cultures. We have used retrovirus mediated gene transfer to demonstrate that marked totipotent hematopoietic stem cells are both maintained and can be amplified in such cultures, and then subsequently regenerate and sustain lympho-myeloid hematopoiesis in irradiated recipients. Marrow cells from 5-fluorouracil-treated male mice were infected with a recombinant virus carrying the neomycin resistence gene and seeded onto irradiated adherent layers of pre-established, long- term marrow cultures of female origin. At 4 weeks, cells from individual cultures were transplanted into single or multiple female recipients. Southern blot analysis of hematopoietic tissue 45 days posttransplantation showed retrovirally marked clones common to lymphoid and myeloid tissues in 14 of 23 mice examined. Strikingly, for 3 of 4 long-term cultures, multiple recipients of cells from a single flask showed marrow and thymus repopulation with the same unique retrovirally marked clone. These results establish the feasibility of retroviral-marking techniques to demonstrate the maintenance of totipotent lympho-myeloid stem cells for at least 4 weeks in the long- term marrow culture system and provide the first evidence of their proliferation in vitro. Therefore, such cultures may serve as a starting point for identifying factors that stimulate totipotent hematopoietic stem cell expansion. 相似文献
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Spontaneous outgrowth of immortalized Epstein-Barr virus (EBV) infected B-cell clones will occur from cultures of peripheral blood mononuclear cells (PBMNCs) of some persons with a history of EBV infection. We determined that outgrowth of such clones may be reproducibly modulated by supplementation of cultures with the hematopoietic growth factors GM- CSF and interleukin-3 (IL-3). Continuous supplementation of cultures with GM-CSF facilitates emergence of immortalized B-cell clones, whereas supplementation with IL-3 completely prevents their emergence. The effect of GM-CSF may be direct, at least in part, as the proliferation of pure clones of EBV-transformed B lymphocytes was augmented in response to GM-CSF. An indirect mechanism appears to be responsible for the inhibition of transformed B-cell outgrowth in response to IL-3, as IL-3 had no inhibitory effect on proliferation of pure transformed B-cell clones and IL-3-mediated inhibition could be eliminated by antibody neutralization of gamma-interferon (gamma-IFN) or tumor necrosis factor-alpha (TNF-alpha) early in culture. The mechanisms of these effects deserve further study and may have clinical relevance to use of hematopoietic growth factors for support of bone marrow (BM) function in immunocompromised patients. 相似文献
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Postoperative Expansion is not a Primary Cause of Infection in Immediate Breast Reconstruction with Tissue Expanders 下载免费PDF全文
Tomer Avraham MD Katie E. Weichman MD Stelios Wilson BS Andrew Weinstein MD Nicholas T. Haddock MD Caroline Szpalski MD Mihye Choi MD Nolan S. Karp MD 《The breast journal》2015,21(5):501-507
Perioperative infection is the most common and dreaded complication associated with tissue expander (TE) breast reconstruction. Historically, the expansion period was thought to be the time of greatest hazard to the implant. However, recent institutional observations suggest infectious complications occur prior to expansion. This investigation, therefore, was conducted to determine the timing of infectious complications associated with two‐stage TE breast reconstructions. Following IRB approval, a retrospective review of all consecutive two‐stage immediate TE breast reconstructions at a single institution from November 2007 to November 2011 was conducted. Reconstructions were then divided into two cohorts: those suffering infectious complications and those that did not. Infectious complications including minor cellulitis, major cellulitis, abscess drainage, and explantation were identified. Various operative and patient variables were evaluated in comparison. Eight hundred ninety immediate two‐stage TE breast reconstructions met inclusion criteria. Patients suffering infection were older (55.4 years versus 49.3 years; p < 0.001), and more likely to have therapeutic mastectomy (94% versus 61%; p < 0.0001), the use of acellular dermal matrix (ADM; 72.5% versus 54.9%; p = 0.001), and greater initial TE fill (448.6 mL versus 404.7 mL; p = 0.0078). The average time to developing of infectious symptoms was 29.6 days (range 9–142 days), with 94.6% (n = 87) of infections prior to the start of expansion. Perioperative infections in immediate two‐stage TE to implant breast reconstructions are significant and occur mostly prior to the start of expansion. Thus, challenging the conventional wisdom that instrumentation during expander filling as the primary cause of implant infections. Possible etiologic factors include greater age, therapeutic mastectomy versus prophylactic mastectomy, larger initial TE fill, and the use of ADM. 相似文献
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目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术18例,其中右半结肠切除术4例,横结肠癌根治术3例,乙状结肠癌根治术5例,乙状结肠癌姑息切除术并肝转移癌电凝固化1例,胃癌术后复发转移行探查活检1例,胃巨大恶性淋巴瘤行探查活检1例,晚期回肠癌行小肠侧侧吻合术1例,乙状结肠腺瘤切除术2例。结果均获成功,无中转开腹,手术时间平均165.0分钟。术后平均31.2小时胃肠功能恢复,无并发症发生,术后平均住院8.2天。13例切除肿瘤的结肠癌术后随访2月~30月,仅1例横结肠癌术后23月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。 相似文献
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This paper reports on the development of a questionnaire to assess self reported reasons for substance use in schizophrenia: the ‘reasons for substance use in schizophrenia’ (ReSUS) scale and explores the relationship between reasons for use, psychiatric symptoms and substance use in a sample of 230 people with psychosis. Principal components analysis revealed three subscales: “coping with distressing emotions and symptoms', “social enhancement and intoxication” and “individual enhancement”. Predicted associations were partially supported. ‘Coping’ reasons for use were related to positive symptoms, general symptoms, global functioning, depression and suicide behaviour as well as substance use (quantity of use and problems related to use). ‘Individual enhancement’ reasons were related to positive symptoms, to global functioning and to negative consequences of substance use. ‘Social enhancement and intoxication’ reasons were related to negative consequences of use but not to psychopathology. The findings suggest that the ReSUS is a reliable and valid instrument which can be used to explore self reported reasons for substance use and their relationship to psychotic symptoms in people with schizophrenia and other psychotic disorders. 相似文献