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991.
992.
In this study, dietary modulation of 7,12-dimethylbenz[a]anthracene (DMBA)-induced adrenal toxicity in rats was investigated. Beginning at postnatal day (PND) 21, female Sprague-Dawley rats were fed either soy-containing NIH-31 diet or soy- and alfalfa-free 5K96 diet. On the first day of diestrus when the animals were PND 50 +/- 5, rats received either an oral dose of 80 mg/kg DMBA or sesame oil, the vehicle, and were sacrificed at 24, 36, or 48 h after treatment. Apoptosis was manifested at 24 and 36 h after DMBA treatment in the zona reticularis (ZR) and the zona fasciculata (ZF) of the adrenal cortex; this was followed by severe hemorrhagic necrosis at 48 h. DMBA-induced apoptosis, evaluated by the TUNEL assay, immunohistochemical analysis of activated caspase 3, and the ratio of expression of pro-apoptotic Bax to anti-apoptotic Bcl2, was greater in rats fed NIH-31 diet relative to rats fed 5K96 diet at 24 h after treatment. Four of six DMBA-treated rats fed 5K96 diet had severe adrenal necrosis by 48 h, whereas this lesion was present in only two of six DMBA-treated rats fed NIH-31 diet. DMBA also caused a significant decrease of serum corticosterone relative to controls at 48 h in rats fed 5K96 diet. The present study indicated that diet modulates DMBA-induced adrenal toxicity in female rats, with increased apoptosis early and reduced necrosis later in rats fed a soy-containing diet.  相似文献   
993.
目的 探讨三七、茜草(SQ)复方治疗置铜宫内节育器(Cu-IUD)所致子宫异常出血的作用机理。方法 制 作家兔置Cu-IUD动物模型,以吲哚美辛作对照,观察SQ复方对置Cu-IUD家兔模型子宫匀浆中组织型纤溶酶原激 活物(t-PA)活性的影响。结果 置Cu-IUD家兔模型子宫匀浆中t-PA的含量增高(P<0.01),经SQ复方治疗后与模 型组比较有显著性差异(P<0.01),说明SQ复方能减少家兔子宫匀浆中t-PA的含量,降低t-PA的活性。结论 SQ 复方通过降低置Cu-IUD家兔子宫内膜局部的纤溶活性而达到止血的目的。  相似文献   
994.
Steno-Occlusive Changes in the External Carotid System in Moyamoya Disease   总被引:1,自引:0,他引:1  
To evaluate the steno-occlusive changes in the external carotid system in moyamoya disease, cerebral angiograms of 39 moyamoya patients were retrospectively reviewed. There were 26 females and 13 males, age ranged from 4 to 62 years with a mean of 26 years. Initial symptoms were ischaemia in 27 patients, haemorrhage in 9, and none in 3. Stenosis, occlusion, and dilatation in the external carotid system were analysed angiographically. No stenosis or occlusion of the superficial temporal artery, middle meningeal artery, or occipital artery was observed in either preoperative or postoperative follow-up angiograms in any patients. Steno-occlusive changes do not occur in the external carotid system, but are confined in the internal carotid system in moyamoya disease.  相似文献   
995.
[目的 ]了解肺癌病人 5年生存率及影响肺癌病人 5年生存的因素。 [方法 ]对 1993~ 1996年到河北省职工医学院附属医院外科治疗的 86例肺癌患者进行为期 5年的随访观察 ,对 10个可能影响肺癌生存的因素用Cox回归模型进行分析 ;使用寿命表分析肺癌病人的 5年生存率。 [结果 ]肿瘤偏大或虽不大但累及的周围组织、结构较多 ,有远端淋巴转移是影响肺癌病人 5年生存的危险因素 ;对癌肿采取手术治疗、化疗 ,首发症状距就诊时间长是其保护因素 ;肺癌病人的 1~ 5年生存率分别为 76 77%、49 78%、3 3 5 7%、2 1 3 6%和 14 2 4% ,中位生存时间为 2 3 9月。 [结论 ]肿瘤的大小、治疗手段、淋巴转移和首发症状距就诊时间与肺癌的病人 5年生存有关。  相似文献   
996.
目的:观察制备的重组色素上皮细胞衍生因子(rPEDF)对鸡胚绒毛尿囊膜(CAM)血管及兔角膜新生血管的抑制作用。方法:制备rPEDF,采用鸡胚绒毛尿囊膜分析,观察rPEDF抑制新生血管生长情况。利用碱烧伤制作兔角膜新生血管模型,观察rPEDF抑制角膜新生血管生长状况。结果:rPEDF能明显抑制鸡胚绒毛尿囊膜血管生长。rPEDF治疗组兔角膜新生血管长度及生长面积明显少于对照组(P<0.05),差异有统计学意义。结论:制备的rPEDF抑制鸡胚绒毛尿囊膜血管生长,抑制兔角膜新生血管的形成。  相似文献   
997.
The potential use of genetic tests in insurance has raised concerns about discrimination and individuals losing access to health care either because of refusals to test for treatable diseases, or because test-positives cannot afford premiums. Governments have so far largely sought to restrict the use of genetic information by insurance companies. To date the number of tests available with significant actuarial value is limited. However, this is likely to change, raising more clearly the question as to whether the social costs of adverse selection outweigh the social costs of individuals not accessing health care for fear of the consequences of test information being used in insurance markets. In this contribution we set out the policy context and model the potential trade-offs between the losses faced by insurers from adverse selection by insurees (which will increase premiums reducing consumer welfare) and the detrimental health effects that may result from persons refusing to undergo tests that could identify treatable health conditions. It argues that the optimal public policy on genetic testing should reflect overall societal benefit, taking account of these trade-offs. Based on our model, the factors that influence the outcome include: the size of and value attached to the health gains from treatment; deterrent effects of a disclosure requirement on testing for health reasons; incidence of the disease; propensity of test-positives to adverse select; policy value adverse selectors buy in a non-disclosure environment; and price elasticity of demand for insurance. Our illustrative model can be used as a benchmark for developing other scenarios or incorporating real data in order to address the impact of different policies on disclosure and requirement to test.  相似文献   
998.
目的探讨口岸人员体重指数(Body Mass Index-BMI)与心血管病危险因素聚集性的关系,为口岸工作人员预防和减少心血管病提供科学指导.方法对264名口岸工作人员的体检资料以体重指数为单因数作统计学的分析.结果在偏瘦、正常和肥胖体型间,男性甘油三脂(TG)、胆固醇(TC)和女性甘油三脂的水平有显著性差异(F值各为8.9、5.9、12.9,P<0.01),血糖(GLU)男、女性组中均无显著性差异(F值各为0.9、0.3,P>0.01).在血脂血糖异常检出率中,男性甘油三脂、胆固醇和女性甘油三脂的异常检出数在各组体重指数人数中有显著性差异(x2各为25.9、15.6、12.1,P<0.01),血糖在男、女性组中无显著性差异(P值各为0.13、2.6,P>0.01).高血压发生率在偏瘦、正常与肥胖体型者中差异较为明显(正常型为1.98%,肥胖型为5.17%).结论甘油三脂、胆固醇的水平与异常检出数和高血压的发生率均是随着体重指数升高而升高的.在多种心血管危险因素个体聚集性的比较中,男性肥胖者心血管危险因素发生的科学指导,有助于控制和减少心血管病的发生.  相似文献   
999.
When considering the trends in disease management, the focus of healthcare in the US has shifted from communicable diseases, which can most often be managed successfully, to chronic diseases, which are currently not managed very well. Chronic diseases, such as diabetes mellitus, become a lifelong health problem for the individual, the family, and in the workplace. Currently, there is no vaccine to prevent diabetes and no cure for diabetes once acquired. In order to improve the quality of care for diabetes, national performance measures have been developed to provide a unified set of diabetes-specific performance and outcome measures.The Diabetes Quality Improvement Project (DQIP) founded in 1997 through a partnership between the Center for Medicare and Medicaid Services, the National Committee for Quality Assurance, and the American Diabetes Association, established a single, standardized set of performance measures for diabetes care quality improvement and accountability in the US, which were published in 1998. The DQIP measures are noteworthy as a model for many other chronic diseases. Indeed, the DQIP represents the first widely adopted comprehensive performance measurement standards, not just for diabetes but for any single chronic disease. This is of further significance since it was developed by a coalition of public and private entities in the US.In order to prevent long-term complications from diabetes, there needs to be a physician-coordinated treatment plan involving a team approach to the problem. When such a physician-coordinated treatment plan is developed in conformance with the comprehensive performance measures, the prospects for a greater impact on diabetes might be enhanced.Overall, national performance measures for diabetes care have been widely adopted into health plan quality initiatives and have resulted in increased efforts to promote preventative screening and testing. Better compliance has lead to more stringent glucose control and helped to educate the public on the utility of the glycosylated hemoglobin level test for finding those at risk for microvascular and neuropathic complications. While more Americans with diabetes are receiving the recommended standards of care as a result of the implementation of national performance measures, diabetes management remains suboptimal but achievable.The authors concluded from this review that national performance measures have provided health plans and providers with objective tools to measure quality; however, these measures now need to move to prevention standards and initiatives. Policy development for diabetes care must continue to move from managing chronic illness to preventative screening of pre-diabetes through to identification and modification of lifestyle risk factors.  相似文献   
1000.
Sickle cell disease (SCD), an inherited group of blood disorders, is a major public health problem worldwide. Patients experience severe anemia, increased risk of life-threatening infections, painful crisis, and chronic organ damage. Access to comprehensive care for SCD is known to improve outcomes; however, it is only reported from large urban centers serving one metropolitan area. Alabama, US, is a largely rural state with a significant number of children born each year with SCD. Prior to the development of our regional clinic network, the Children and Youth Sickle Network (CYSNSM), 50% of patients identified by newborn screening were not enrolled in comprehensive sickle cell care. The majority of non-enrolled patients lived in southern Alabama. Rural areas in this region are particularly plagued by poverty and poor access to healthcare. Life expectancy is equivalent to residents of Sri Lanka. This area has 15.7 doctors/10 000 residents compared with the statewide ratio of 41.9 doctors/10 000 residents.To improve access to care, a regional clinic network, the CYSNSM, was established in 1995. This paper reviews the impact of the CYSNSM on pediatrie SCD in Alabama over the first 5 years of implementation.Since its inception in 1995, the CYSNSM has provided care for 923 patients compared with 450 prior to the development of the clinic network. Currently, 90% of all cases identified by newborn screening are enrolled compared with 50% pre-CYSNSM. Prior to the network, the average age of patients at their first clinic visit was 21 months. In the post-CYSNSM period, the average age at first clinic visit decreased substantially to 5.3 months. Prior to the CYSNSM, patients traveled on average 90 miles to a comprehensive clinic. Post-CYSNSM, this distance has been cut in half to an average of 45 miles. A total of 70% of patients now live within 30 miles of a clinic. Most importantly, the infection death rate has decreased from 5.71 deaths/100 patient years to 1.94 deaths/100 patient years.The development, implementation, and evaluation of the CYSNSM show that comprehensive care delivery in a rural setting is feasible and improves outcomes in pediatric SCD.  相似文献   
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