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31.
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories. Received: 28 May 1996/Accepted: 30 August 1996  相似文献   
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We report a case of calcified chronic encapsulated intracerebral haematoma (ICH) in a 29-year-old female who presented with progressive left sided weakness and intermittent seizures since childhood. The preoperative magnetic resonance (MR) imaging of the head initially suggested that a partially thrombosed aneurysm or vascular malformation was present. However, no vascular stain was found on the digital subtraction angiography (DSA) of both the carotid and vertebral arteries. The excised mass was histologically diagnosed as a chronic ICH. We traced the patient's medical history and found that at the age of one she sustained a head injury after a fall. So far, to our knowledge, no case of epilepsy secondary to a calcified chronic encapsulated ICH occurring 28 years after head injury has been reported. Calcified chronic encapsulated ICH concomitant with new bone formation within is even rarer. The possible pathogenesis of this case is discussed.  相似文献   
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口服谷氨酰胺颗粒对烧创伤患者的疗效及安全性分析   总被引:15,自引:5,他引:10  
目的观察口服谷氨酰胺(Gln)颗粒对烧(创)伤及大手术患者的疗效及可能发生的不良反应.方法采用随机双盲、安慰剂对照法,将受试患者分为Gln组和对照组,每组60例,两组患者采用等氮、等热量的营养支持.Gln组口服或管饲Gln 0.5 g·kg-1·d-1,对照组使用同等剂量的安慰剂甘氨酸,疗程均为7 d.比较用药前后两组患者肠黏膜屏障功能、蛋白代谢、免疫功能、肝和肾功能的变化及不良反应等. 结果伤后两组患者血浆Gln浓度明显低于正常值,而血浆二胺氧化酶(DAO)活性、内毒素含量、肠黏膜通透性[尿乳果糖/甘露醇(L/M)]及尿氮排量均明显增高;但Gln组用药7 d后血浆Gln浓度与用药前比较增加38.04%(P<0.01).Gln组血浆前白蛋白、转铁蛋白及白细胞介素2(IL-2)含量均显著高于对照组(P<0.01),升幅分别为21.19%、51.11%、57.54%.血浆DAO活性、L/M比值、内毒素含量及尿氮排量明显低于对照组,降幅分别为47.26%、52.18%、22.22%、27.78%(P<0.05或0.01).两组患者的血浆总蛋白、白蛋白、血尿常规及肝、肾功能在用约前后变化不明显(P>0.05).用药后有少数患者出现轻微不良反应如恶心、腹泻和便秘等,2~3 d后自行缓解,两组间比较,差异无显著性意义(P>0.05).结论口服Gln能显著提高患者血浆Gln浓度,明显减轻伤后肠黏膜受损程度,并能促进机体蛋白合成,降低蛋白分解,提高机体免疫功能,且临床应用无明显不良反应.  相似文献   
35.
Objective To study the pulmonary functions of pediatric ALI/ARDS(acute lung injury/acute respiratory distress syndrome) survivors. Method A prospective cohort study of all survivors of ALI/ARDS in the PICU of Beijing Children's Hospital was performed. Patients were divided into three groups(0-3 years of age,3 ~ 7 years of age, and over 7 years of age) and followed up three months after diagnosis. Results There were 36 survivors in total of 44 ALl patients, three patients lost follow-up, 12 died and 21 survived. Five survivors refused to participate in the study because of asymptomatic, and one was unable to participate because of lymphoma com-bined with sepsis. A total of 15 children completed the whole survey (11 patients were less than 3 years old, andfour were over 7 years of age). Twelve patients had no discomfort in their respiratory tracts. Three months after be-ing enrolled, the pulmonary functions of all children improved, especially in terms of tidal volume and respiratory compliance (P<0.05). Conclusions The abnormal respiratory symptoms and signs in most children disap-peared three months after discharge. Most survivors still have pulmonary dysfunction at 3 monthes after discharge, but better than discharge.  相似文献   
36.
以人为本理念在全程护理服务中的实践   总被引:6,自引:2,他引:4  
为了探索既符合中国国情又能满足病人需求的护理服务新模式,浙江省台州市中心医院自2002年开始试行全程护理服务。在实施护理中以病人为中心,从理念上、环境上、权益上、细节上为病人提供全面、全员、全程的人本服务;在管理实践中,提倡“尊、理、信、谐、通、创”六字理念,将管理视为服务,实行人本管理。通过3年的实践,整体护理质量、病人满意度、护士对工作满意度均有显著提高。  相似文献   
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4-Aminopyridine (4-AP) induced an atropine- and tetrodotoxin (TTX)-insensitive contraction (resistant contraction), in a concentration-dependent manner, in the isolated jejunum of rabbits. The failure of specific antagonists of histamine, serotonin and substance P to affect this resistant contraction ruled out the participation of histamine, serotonin and/or substance P. Antiserum against neuropeptide Y (NPY) reduced this resistant contraction in a concentration-dependent manner and inhibited the action of 4-AP totally at a high concentration (1.25% dilution) whereas normal serum lacked this ability. This suggested that the release of NPY was involved in this 4-AP-induced resistant contraction. Radioimmunoassay of NPY-like immunoreactivity in isolated synaptosomal preparations indicated that 4-AP possessed the ability to induce the release of NPY. However, guanethidine did not affect the actions of 4-AP, indicating that NPY is released mainly from non-adrenergic nerves. Our results indicate that 4-AP induces the release of NPY from non-adrenergic nerves to produce an atropine- and TTX-resistant contraction in the isolated jejunum of rabbits.  相似文献   
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We have previously reported that the J774A.1 macrophage-like tumor cell line produces two potent monokines which stimulate the growth of osteoblasts and chondrocytes. These growth factors, which have an affinity for heparin-agarose, have been termed HEP I (a 30 Kd PDGF-like molecule) and HEP II (an approximately 20 Kd molecule), respectively, based on their elution profile. Unlike HEP I, HEP II does not stimulate the growth of fibroblasts. Extensive biological and chromatographic studies disclosed that HEP II appears to be a unique bone cell mitogen unlike any known growth factor, including the FGFs, IL-1s, and TNFs, EGF, IGF-I and -II, TGF-beta, beta 2 microglobulin, G-CSF, CSF-1 and GM-CSF. To characterize more fully the effects of the macrophage-derived monokines on osteoblast growth and function, clones were derived from calvaria explant cultures. Two clones, SDFRC-2.05 and SDFRC-3, were developed and found to exhibit osteoblastic characteristics, including high levels of alkaline phosphatase, synthesis of type I but not type III collagen, and an increased intracellular cAMP production in response to PTH. The SDFRC-3 cells exhibited a polygonal morphology like that of the explant-derived cells while SDFRC-2.05 cells exhibited a more fibroblastic morphology. When tested on the explant cultures and clones, HEP I and HEP II were found to stimulate DNA synthesis and increase protein per culture, but decreased alkaline phosphatase activity. Clone SDFRC-3 was found to be more responsive to HEP II than clone SDFRC-2.05. Both monokines were found to be more potent mitogens for bone cells than TGF-beta. HEP II, but not HEP I or TGF-beta, induced a transformation of bone cells from a polygonal to a fibroblastic morphology, suggesting the induction of migration prior to proliferation. Thus, macrophages may be responsible not only for bone repair but also for ensuring the linkage of bone formation to resorption during physiological remodeling.  相似文献   
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