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1.
Industrial development in Africa has carried with it significant health costs. These costs are normally defined rather narrowly by those concerned about occupational or industrial health and safety and refer only to the health consequences of worker exposure to specific hazardous processes, materials or environmental conditions associated with the workplace. A more comprehensive measurement of industrial health costs, however, must also include an assessment of the impact which industrial development and the creation of an industrial workforce has on ecological relationships, environmental conditions and patterns of sickness and health in the areas surrounding industrial centers. Traditional definitions of occupational health also tend to focus attention on the immediate causal linkages which exist between the development of particular industrial processes and specific health hazards. Yet any attempt to fully understand the causes of industrial health problems in Africa must look beyond these immediate causal linkages and examine the wider political and economic forces which determine the shape of industrial development and the extent to which the health costs of this development are borne by industrial workers and their families, as well as by people who may not be directly or even indirectly connected to industrial development, but may, nonetheless, be exposed to its health risks. The paper surveys the direct and indirect health costs of mining, large scale agriculture, and manufacturing in Africa and examines the economic and political interests which have determined the distribution of these costs.  相似文献   
2.
RMP-7, a nine-amino acid bradykinin analogue, has been shown in animals to temporarily increase the permeability of the blood brain barrier to small molecules including amphotericin B, when administered intravenously. We sought to evaluate the safety of escalating doses of RMP-7 administered to human volunteers with the acquired immune deficiency syndrome (AIDS). Six HIV antibody-positive adults with CD4+ cell counts <50/mm3 received three increasing doses of RMP-7 on successive days: 30 ng/kg, 100 ng/kg and 300 ng/kg infused over 2, 2 and 10 min, respectively. Adverse experiences were dose-related, mild-moderate in intensity, primarily related to vasodilation and resolved rapidly without sequelae. Mean maximum increases in pulse rate at 30 ng/kg, 100 ng/kg and 300 ng/kg were 4.0, 7.8 and 28.2 beats per min, respectively. The maximum changes in average mean arterial pressure were +7.7, +5.6 and −0.2 mmHg from baseline, respectively. Minor increases in liver enzymes were noted in three patients, all with pre-existing enzyme elevations. Despite the high frequency of both occult and overt cardiovascular abnormalities in advanced HIV infection, RMP-7 is shown to be safe in this group of AIDS patients at all dosage levels tested, with adverse effects similar to previous experience in healthy humans.  相似文献   
3.
Data from the Social Security Administration's 1982 New Beneficiary Survey and Master Beneficiary Record were matched with 1984 data from the Medicare Automated Data Retrieval System to study the effects of self-reported health on subsequent health service usage and survival. Proportionately, more new retired workers who reported poorer health in 1982 were decreased by December 1984. Functionally dependent beneficiaries as determined by the Functional Capacity Limitation Index had death rates four to five times greater than those who reported no limitations. The health status of retired workers who received Social Security benefits before age 65 was no better than beneficiaries 65 or over. Decedents were more likely than survivors to incur Medicare charges, and to have substantially higher median charges--$8,834 compared with $285.  相似文献   
4.
目的:采用HPLC法测定四川粉葛中葛根素的含量。方法:色谱柱为依利特C18柱(4.6min&;#215;150mm,5μm),流动相为甲醇-水(25:75),流速为0.8ml/min,检测波长为250nm,柱温为25℃。结果:葛根素在0.0880~0.7040μg范围内峰面积与进样量呈良好的线性关系,回归方程为A=336.35X-1.7716,r=1.0000,其平均同收率为100.01%,RSD为0.14%(n=6)。结论:该方法简便易行,结果准确,可用于四川粉葛药材的质量控制。  相似文献   
5.
The lipophilic, monocationic copper(II) complex of the diiminedioxime ligand 2,10-di-n-butyl-3,9-dimethyl-1,4,8,11-tetraazaundeca-1,3,8,10-tetraen-1,11-dione dioxime was synthesized and labeled with 64Cu. The biological properties of the 64Cu-labeled complex were measured in vivo and in vitro. In vivo, the complex shows uptake by the heart similar to that of 99mTc-tetrofosmin. In vitro, its uptake by multidrug resistant and non-resistant MES-SA tumor cells parallels that of 99mTc-MIBI, a well-characterized marker of multidrug resistance. These results suggest that this class of copper complexes may form the basis for the development of a 64Cu PET radiopharmaceutical for the functional imaging of multidrug resistance and/or myocardial perfusion.  相似文献   
6.
The association between possession of the APOE epsilon4 allele and unfavourable outcome after traumatic brain injury (TBI) suggests that the apolipoprotein E protein (apoE) plays a key role in the response of the human brain to injury. ApoE is known to regulate cholesterol metabolism in the periphery through its action as a ligand for receptor mediated uptake of lipoprotein particles (Lps). Greater understanding of cholesterol metabolism in the human central nervous system may identify novel treatment strategies applicable to acute brain injury. We report findings from the analysis of lipoproteins in the cerebrospinal fluid (CSF) of patients with TBI and non-injured controls, testing the hypothesis that remodeling of CSF lipoproteins reflects the response of the brain to TBI. CSF Lps were isolated from the CSF of controls and patients with severe TBI by size exclusion chromatography, and the lipoprotein fractions analysed for cholesterol, phospholipid, apoAI, and apoE. There was a marked decrease in apoE containing Lps in the TBI CSF compared to controls (p=0.002). After TBI there was no significant decrease in apoAI containing CSF Lps (CSF LpAI), but the apoAI resided on smaller sized particles than in control CSF. There was a population of very small sized Lps in TBI CSF, which were associated with the increased cholesterol (p=0.0001) and phospholipid (p=0.040) seen after TBI. The dramatic loss of apoE containing Lps from the CSF, and the substantial increase in CSF cholesterol, support the concept that apoE and cholesterol metabolism are intimately linked in the context of acute brain injury. Treatment strategies targeting CNS lipid transport, required for neuronal sprouting and synaptogenesis, may be applicable to traumatic brain injury.  相似文献   
7.
目的评价中心静脉导管留置治疗胸腔积液的疗效。方法257例胸腔积液患者分为两组,治疗组207例,应用胸腔留置中心静脉导管治疗;对照组50例,常规胸穿抽液治疗,观察并比较不同治疗方法的疗效、并发症等指标。结果两组对比多项指标差异有显著性(P〈0.05)。结论采用中心静脉导管治疗胸腔积液可减少胸穿次数、降低反应,提高治愈率。  相似文献   
8.
Electromechanical Interval and Strokes After Ablations of AF . Introduction: Atrial fibrillation (AF) is associated with increased risk of embolic stroke. Catheter ablation of AF provides an effective therapy for patients with symptomatic and drug‐refractory AF. The aim of this study was to evaluate whether the atrial electromechanical interval is useful in identifying patients at risk of stroke after successful catheter ablation. Methods and Results: A total of 279 AF patients who received catheter ablation and showed no evidence of recurrences were enrolled. Electromechanical interval (PA–PDI) was determined as the time interval from the initiation of P wave deflection to the peak of mitral inflow A wave on pulse wave Doppler imaging. The PA–PDI interval was measured for each patient after the 3‐month blanking period of catheter ablation. The clinical endpoint was the occurrence of ischemic stroke. During the follow‐up of 46.5 ± 17.2 months, 6 patients suffered from ischemic strokes. Patients with strokes had higher CHA2DS2–VASc scores and longer PA–PDI intervals (138.7 ± 12.4 ms vs 161.2 ± 7.7 ms, P value < 0.001) compared to those without strokes. At a cutoff point of 150 ms identified by ROC curve, the positive and negative predictive values of the PA–PDI interval to predict stroke were 86.7% and 100%, respectively. The PA–PDI interval improved the predictive performance of the CHA2DS2–VASc score, and the area under the ROC curve increased from 0.75 to 0.85. Conclusions: Our results suggest that the PA–PDI interval is a useful tool to identify patients with high risk of stroke after successful catheter ablation of AF. (J Cardiovasc Electrophysiol, Vol. 24, pp. 375‐380, April 2013)  相似文献   
9.
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010)  相似文献   
10.
Gender Differences in Patients With AVNRT. Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender‐related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation. Methods and Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study. We evaluated the gender differences in their electrophysiological characteristics. Women had a significantly younger age of onset, higher incidence of multiple jumps, shorter AH interval, atrial effective refractory period (ERP), anterograde fast pathway ERP, anterograde slow pathway ERP, and retrograde slow pathway ERP, and longer ventricular ERP than men. The incidence of baseline ventriculoatrial dissociation was lower in women than in men. Women needed less isoproterenol/atropine to induce AVNRT. No gender differences in the radiation exposure time, procedure time, complication rate, acute success rate, or second procedure rate were noted. Both typical and atypical AVNRT were more predominant in women. In the patients with atypical AVNRT, there was no significant gender difference in incidence of baseline ventriculoatrial dissociation; however, the retrograde slow pathway ERP was significantly shorter in women than in men. Women of premenopausal age (≤50 years old) had a significantly higher incidence of anterograde multiple jumps and a retrograde jump phenomenon, and a shorter anterograde slow pathway ERP and retrograde slow pathway ERP than those of women over 50 years old. Conclusion: Gender differences in the anterograde and retrograde AV nodal electrophysiology were noted in the patients with AVNRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1114‐1119)  相似文献   
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