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11.
A total of sixty-one subjects occupationally exposed to chromium in an industry which manufactures chromium sulphate and fifteen control subjects from a nearby industry which does not manufacture any chromium related compounds were studied. The history of each subject was recorded on pre-designed form through interview and a routine medical examination was carried out. Blood samples (5-6 ml) were collected for the estimation of chromium and semen samples were collected for semen analysis and the determination of copper and zinc levels in the seminal plasma. Clinical examination revealed nasal perforation in 10 subjects (out of 61) in the exposed group as compared to none in the control group. A significantly higher level of chromium was observed in the blood of the exposed workers as compared to the control. The concentration of zinc in seminal plasma was lower while the level of copper was higher in the exposed group as compared to the control. However, these changes were not statistically significant. Statistically significant higher numbers of morphologically abnormal sperms were noticed in the exposed group with respect to the control. Further analysis of the data indicated that about 53% of the exposed subjects showed less than 30% normal forms as compared to 10% in control subjects. However, no significant alterations in semen volume, liquefaction time, mean pH value, sperm viability, concentration or motility, were noticed between chromium exposed and unexposed workers. The data also indicates that exposure to chromium has some effect on human sperm as a significant positive correlation (r=0.301) was observed between percentages of abnormal sperm morphology and blood chromium levels (p=0.016) after pooling all the data of the control and exposure groups.  相似文献   
12.
Manganese-induced early biochemical changes and effects of supplementation of magnesium nitrate (Mg(NO3)2) and antioxidant vitamins (A, C, D and E) were studied in rats intoxicated with manganese. Significant elevation in the level of chlorides in plasma, erythrocytes, liver and cerebellum, and a decrease in plasma inorganic phosphate (pi) with an increase in liver pi were observed in animals exposed to manganese as compared to controls. The level of erythrocyte-acid labile phosphate (ALP), nicotinamide adeninedinucleotide (NAD+) and plasma sialic acid (N-acetylneuraminic acid, NANA) also increased significantly. Elevated levels of chlorides in plasma, erythrocytes and cerebellum reversed to normal control values whereas liver chlorides restored partially by the supplementation of Mg(NO3)2. Vitamins supplementation was effective to reverse chlorides level in erythrocytes, liver and cerebellum. Decreased level of pi in plasma and the highly elevated level of erythrocyte ALP were also recovered in animals received Mg(NO3)2 in addition to MnSO4. However, such effect of Mg(NO3)2 was not seen in lowering the elevated level of NANA that restored by the administration of vitamins. Thus, the early alterations in plasma levels of chlorides, pi, and NANA and erythrocyte-ALP seem to be an indicative of early manganese toxicity while Mg(NO3)2 and vitamins supplementation appear to provide, at least in part, protection against manganese toxicity.  相似文献   
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Assessment of respirable dust, personal exposures of miners and free silica contents in dust were undertaken to find out the associated risk of coal workers' pneumoconiosis in 9 coal mines of Eastern India during 1988-91. Mine Research Establishment (MRE), 113A Gravimetric Dust Sampler (GDS) and personal samplers (AFC 123), Cassella, London, approved by Director General of Mines Safety (DGMS) were used respectively for monitoring of mine air dust and personal exposures of miners. Fourier Transform Infra-red (FTIR) Spectroscopy determined free silica in respirable dusts. Thermal Conditions like Wet Bulb Globe Temperature (WBGT) index, humidity and wind velocity were also recorded during monitoring. The dust levels in the face return air of both, Board & Pillar (B&P) and Long Wall (LW) mining were found above the permissible level recommended by DGMS, Govt. of India. The drilling, blasting and loading are the major dusty operations in B&P method. Exposures of driller and loader were varied between, 0.81-9.48 mg/m3 and 0.05-9.84 mg/m3 respectively in B&P mining, whereas exposures of DOSCO loader, Shearer operator and Power Support Face Worker were varied between 2.65-9.11 mg/m3, 0.22-10.00 mg/m3 and 0.12-9.32 mg/m3 respectively in LW mining. In open cast mining, compressor and driller operators are the major exposed groups. The percentage silica in respirable dusts found below 5% in all most all the workers except among query loaders and drillers of open cast mines.  相似文献   
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INTRODUCTION: A number of families in a rural area of Jabalpur District (Madhya Pradesh), India, were affected by repeated episodes of convulsive illness over a period of three weeks. The aim of this investigation was to determine the cause of the illness. METHODS: The investigation included a house-to-house survey, interviews of affected families, discussions with treating physicians, and examination of hospital records. Endosulfan poisoning was suspected as many villagers were using empty pesticide containers for food storage. To confirm this, our team collected blood and food samples, which were transported to the laboratory and analyzed with GC-ECD. RESULTS: Thirty-six persons of all age groups had illness of varying severity over a period of three weeks. In the first week, due to superstitions and lack of treatment, three children died. In the second week, symptomatic treatment of affected persons in a district hospital led to recovery but recurrence of convulsive episodes occurred after the return home. In the third week, 10 people were again hospitalized in a teaching hospital. Investigations carried out in this hospital ruled out infective etiology but no facilities were available for chemical analysis. All persons responded to symptomatic treatment. The blood and food samples analyzed by our team showed presence of endosulfan, which was confirmed by GCMS. One of the food items (Laddu) prepared from wheat flour was found to contain 676 ppm of alpha-endosulfan. CONCLUSIONS: Contamination of wheat grains or flour with endosulfan and its consumption over a period of time was the most likely cause of repeated episodes of convulsions, but the exact reason for this contamination could not be determined. This report highlights the unsafe disposal of pesticide containers by illiterate farm workers, superstitions leading to delay in treatment, and susceptibility of children to endosulfan.  相似文献   
16.
Angul-Talcher area of Orissa is an industrial complex of diversities of industries, which released large number of pollutants into the environment causing environmental pollution and affect the community people as well as the workers working there. Considering the magnitude of the problem pulmonary function study had been carried out in to the community people of this polluted area. The pulmonary function tests (PFT) were carried out in 1099 male and 1072 female subjects except the children below the age of 10 years. Vital capacity (VC) and Forced vital capacity (FVC) were recorded in standing posture. Forced expiratory volume in one second (FEV1) and its percentage (FEV1%) were calculated. The PFT results indicated that in male and female subjects of 10-19 year age group the FVC values were significantly lowered in exposed villagers in comparison to control subjects. In all other age ranges some of the differences have been found to be significant at various levels. The mean values of FVC and FEV1 were higher in control villagers of most of the age groups than that of the exposed villagers PFT values were also presented according to smoking habit. Restrictive type of PFT impairment were noticed more. The male villagers of Gurjunguli showed the maximum - 40.9% followed by Digghi-39.1%, Kulad-35%, Tentuli- 23.4%, Bonda - 16.3%, Gadarkhai-15.4% and Balanda-13.5%. In females the sequence of having higher incidence rate of restrictive diseases were Digghi-37.0%, Tentuli-29.0%, Gurjunguli-25.3%, Kulad - 21.5%, Gadarkhai - 15.3%, Balanda - 15.3% and Bonda - 13.7%. In control village restrictive impairment were 10.7% in male and 7.4% in females. Obstructive types of impairments are comparatively less than restrictive type of impairments. Control male and female subjects had 7.1% and 5.7% of obstructive impairments and they are mostly belonged to higher age groups. In exposed villages obstructive impairments were found in Godarkhai - 6.4%, Kulad - 5.0%, Digghi - 4.2%, Tentuli - 2.6% and Balanda - 1.8% in males and the corresponding figures 5.0%, Digghi - 4.2%, Tentuli - 2.6% and Balanda - 1.8% in males and the corresponding figures in the females were Gadarkhai - 3.0%, Kulad - 2.6%, Digghi - 3.7% Tentuli - 3.0%) and Balanda - 4.0% respectively. The combined types of impairments were more in exposed subjects and they were belonged to higher age groups. The higher prevalence's might be due to the pollution effects of industries situated in and around the concerned villages. Categorically mild type of obstructive impairments was more in control subjects and they belonged to 50 and above year's age group. It is well known that the higher age accounted for lowering PFT values, which might be in the form of mild obstruction.  相似文献   
17.
The present cross sectional study was carried out among 134 ex-workers from quartz stone crushing units. Using the interview technique as a tool for data collection, demographic and occupational details of the subjects were recorded on the predesigned proforma. Standard diagnostic criteria were used for diagnosing silicosis and silico-tuberculosis. The pulmonary functions of the subjects were measured with Spirovit SP-10. The mean age of the males was found to be 33.18 +/- 10.39 yr and that of the females was 30.10 +/- 9.3 yr and for the whole group was 31.77 +/- 9.99 yr. Mean duration of exposure was 2.74 +/- 1.65 yr. The study variables included age, sex, duration of exposure, smoking and respiratory morbidity. Forced Vital Capacity (FVC) which suggests lung parenchymal disorders was found to be significantly reduced with female sex, presence of smoking, increasing duration of exposure and presence of pneumoconiosis, whereas the lung function parameters indicating the status of airways were found to be significantly reduced with all the factors. Therefore, it was concluded that quartz stone workers exposed to approximately 100% free silica had deteriorated lung function which can be attributed mainly to respiratory disorders along with other epidemiological factors such as age, sex, duration of exposure and smoking.  相似文献   
18.
Objectives Welders are exposed to intense heat, toxic metals and their oxides and toxic gases during welding, and some of these substances reported to have adverse effects on reproductive organs. Thus, the present study was planned to investigate the sperm quality as well as reproductive hormones among welders exposed to a complex mixture of pollutants. Methods Seventeen welders aged 43.8±12.0 (mean±SD) years with welding exposure of 1 to 10 years or more participated in this study. They were performing are and gas welding in a workshop. Blood (5–6 ml) and semen samples by masturbation were collected from them. Serum was separated and analyzed for reproductive hormones by RIA techniques. Semen was processed for microscopic examination. Results The results of this study indicated that sperm concentration was in the normal range (≥20 million/ml) in all seventeen welders, however, motility, morphology as well as Hypo Osmotic Swelling test (HOS) demonstrated impairment in few welders, indicating deterioration in sperm quality compared to the reported normal reference value. Compared with the normal value of hormones provided in diagnostic kits brochure, follicle stimulating hormone (FSH), leutinizing hormone (LH) and testosterone levels were in the normal range, except in two subjects who showed higher FSH and LH levels and one who showed a lower value of testosterone. Conclusions This study suggests that welding might have had some adverse effects on sperm motility, morphology and physiologic function even though sperm concentration was in the normal range. Hormonal changes did not show any definite pattern, indicating a need for further study.  相似文献   
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新缩瞳剂包公藤甲素人工合成研究   总被引:11,自引:0,他引:11  
包公藤甲素是从包公藤(Erycibe obtusifolia Benth.)茎中提得的一个新莨菪烷生物碱,具有强烈的缩瞳作用,临床用于治疗青光眼。本文报道用合成的6β-乙酰氧基托品酮为原料,经卤代、水解、还原和N-去甲基化等反应合成包甲素(8)。经光谱测定证实8与天然包甲素的结构完全一致。合成品系外消旋体,其作用机理与天然品相同,而强度则减半。  相似文献   
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