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101.
Dunn  EK; Macchia  RJ; Solomon  NA 《Radiology》1981,139(1):175-180
The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases.  相似文献   
102.
Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants.  相似文献   
103.
104.
Recent evidence indicates that neuropeptide Y modulates neurobiologic responses to ethanol and ethanol consumption. Resistance to the sedative effects of ethanol, voluntary ethanol consumption, or both was found to be inversely related to neuropeptide Y levels in genetically manipulated rat and mouse models. More recently, intracerebroventricular infusion of neuropeptide Y reduced ethanol drinking in rats selectively bred for high ethanol preference, but not in low-ethanol-preferring or in outbred Wistar rats. In the current study, we determined whether intracerebroventricular infusion of neuropeptide Y would reduce voluntary ethanol consumption in high-ethanol-preferring, C57BL/6 mice. We also studied ethanol-induced sedation after intracerebroventricular infusion of neuropeptide Y. Pretreatment with doses of neuropeptide Y, ranging from 3.0 to 10.0 microg, significantly augmented ethanol-induced sedation without altering locomotor activity or plasma ethanol levels. However, neither a 5.0- nor a 10.0-microg dose of neuropeptide Y altered 2-h drinking of a 10% [volume/volume (vol./vol.)] ethanol solution. Consistent with genetic evidence, the results of current pharmacologic studies provide support that neuropeptide Y modulates ethanol-induced sedation.  相似文献   
105.
刘小聪  赵丽华  冯婧  Colin RJ  王素青 《营养学报》2012,34(2):143-146,149
目的探讨CYP1B1对高脂膳食诱导的成年小鼠脂肪代谢的作用。方法 CYP1B1基因敲除(KO)和野生型(WT)雄性成年C57/BL小鼠(6 w龄)各16只,给予低脂(LFD,30%)、高脂肪(HFD,60%)饲料共6 w。小鼠处死后取血清、附睾脂肪和肝脏组织检测相应的生化和分子生物学指标。结果 6 w高脂膳食后,KO小鼠能量摄入总量稍高于WT小鼠,但其体重增量和附睾脂肪组织重量均显著低于WT小鼠;WT小鼠脂肪细胞直径明显大于KO小鼠,且血糖、血清及肝脏组织中甘油三酯(TG)水平亦明显高于KO小鼠;肝脏组织RT-PCR结果显示,CYP1B1基因敲除后,启动脂肪形成的核因子及脂肪合成相关基因如CD36、SREBP1c、SCD1等表达下降,而调控脂肪氧化分解的基因如CPT-1α,UCP-2表达显著上升;蛋白印迹结果显示,CYP1B1基因敲除增强腺苷-磷酸激酶(AMPK)的磷酸化。结论 CYP1B1基因敲除对成年小鼠营养性肥胖的保护作用可能与AMPK磷酸化增强并调控肝脏中脂肪代谢相关基因的表达有关。  相似文献   
106.
荧光原位杂交技术分析人结肠菌群方法研究   总被引:2,自引:0,他引:2  
建立荧光原位杂交技术分析人体内结肠菌群的方法。取受试者新鲜粪便 ,选用 5种特异性的 16SrRNA寡核苷酸探针 ,检测粪便样本收集后的保存时间、温度 ,离心条件及样本固定液存放时间对杂交计数结果的影响。结果建立最佳实验条件为 :粪便样本收集后应尽快在 4℃下保存 ,放置时间不要超过 12小时即作处理 ;样本的适宜离心条件为 70 0g 2分钟 ;样本用多聚甲醛固定后在 - 80℃下存放时间不要超过 5个月。该方法具有较好的稳定性 ,可以有效地检出个体之间结肠菌群的差异。  相似文献   
107.
Cancer incidence and its possible relation to environmental contaminants, including radiation, continues to be a perceived health threat for the arctic-dwelling Alaska Native (Inupiat Eskimo) people despite the lack of a direct link to high-dose exposure. To better understand this concern, all known malignancies diagnosed in this population (n = 177) in three consecutive eight-year periods (1971–1994) were evaluated.The most recent average incidence rate (age-adjusted to world standard population) of 315 per 100 000 (95% confidence interval, CI = 248–382) represents a 33% surge (albeit non-significant) in Alaska Native cancer incidence over the initial period studied. The male rate 366 (95% CI = 266–466) for the same period exceeds the female rate 258 (95% CI = 169–347) by 42%. Two patterns of cancer incidence are seen at the village level. One, a 24 y upward trend found in the villages of Barrow, Point Hope and Kaktovik (combined rate of increase significant [P = 0.047]) associated with lung cancer; and the other, a stable trend over the past 16 y, associated with colon and rectal cancer. Lung cancer is the predominant cancer by site and is primarily a male disease. The recent male lung cancer incidence rate of 137 (95% CI = 73–201) exceeds the female rate by greater than five times. Total lung cancer cases are primarily confined to four villages where the incidence significantly (P = 0.0043) exceeds the remaining population. The major female cancers are colon/rectal and breast with cancer of the cervix virtually eliminated. Breast cancer is found primarily in two villages where its excess is significant (P = 0.025).Inupiat Eskimo cancer epidemiology is unique, differing from both the Alaska Native and other Circumpolar populations. At present, this uniqueness cannot be explained by an overt environmental contaminant exposure. Although tobacco very likely plays a central role, it by itself cannot fully explain the extremely high male lung cancer rate and why only specific villages are affected. Genetic predisposition and environmental factors may play a synergistic role as cofactors. A cooperative investigative effort with the Inupiat population is indicated and may go a long way in reducing cancer concern in the region.  相似文献   
108.
The popular and scientific understanding of acquired immunodeficiency syndrome (AIDS) in the United States has been shaped by successive historical constructions or paradigms of disease. In the first paradigm, AIDS was conceived of as a "gay plague," by analogy with the sudden, devastating epidemics of the past. In the second, AIDS was normalized as a chronic disease to be managed medically over the long term. By examining and extending critiques of both paradigms, it is possible to discern the emergence of an alternative paradigm of AIDS as a collective chronic infectious disease and persistent pandemic. Each of these constructions of AIDS incorporates distinct views of the etiology, prevention, pathology, and treatment of disease; each tacitly promotes different conceptions of the proper allocation of individual and social responsibility for AIDS. This paper focuses on individualistic vs collective, and biomedical vs social and historical, understandings of disease. It analyzes the use of individualism as methodology and as ideology, criticizes some basic assumptions of the biomedical model, and discusses alternative strategies for scientific research, health policy, and disease prevention.  相似文献   
109.
医疗费用全程公开的实现方式及效果   总被引:3,自引:2,他引:3  
本文对医疗费用公开过程中的思想认识、软件开发、使用培训及物价部门支持等各种问题进行讨论分析.认为依托医院信息管理系统,实现全程医疗费用公开,并应用IC卡随时查询的方式,可以更好地突出以病人为中心和展示医院良好的自律形象.  相似文献   
110.
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