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71.
Environmental Geochemistry and Health - There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in...  相似文献   
72.

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01–0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20–0.67 and 0.71–0.82), while lower values were observed for non-exposed subjects (r = 0.123–0.423 and 0.331–0.425), respectively.

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73.
The currant clearwing Synanthedon tipuliformis (Clerck) (Sesiidae) is a worldwide pest of black currants, Ribes nigrum. This moth has been observed to feed on nectar of inflorescences of Canada thistles, Cirsium arvense (L.) Scop. This work was undertaken to identify floral compound(s) produced by Canada thistles inflorescences that mediate the response of the currant clearwing. Floral volatiles were collected during the day and analysed by coupled gas chromatography/electroantennographic detection (GC/EAD) and gas chromatography/mass spectrometry (GC/MS). Three compounds consistently elicited EAD response from moth antennae and were identified by GC/MS as phenylacetaldehyde, methyl salicylate and dimethyl salicylate. When the compounds were tested individually or in various combinations in field trapping experiments, a 3-component blend attracted the largest number of female and male currant clearwings. Subsequent field trapping experiments were conducted to determine the optimal attraction dose for the ternary blend using three loadings of 1, 10 and 100 mg loaded into a polyethylene sachet. The highest catches were in traps baited with the 100 mg loading. In all trials, males and mated females were caught in significant numbers, while very low numbers of virgin females were found in the traps. In recent years the efficacy of mating disruption against currant clearwing has been reported as declining. The new kairomone blend identified in this study can be used with the sex pheromone to provide an effective control option for this important pest.  相似文献   
74.
Betel nut fiber (Bn)/polypropylene (PP) composites were prepared in the different ratio of 10:90, 20:80, 30:70, 40:60 (Bn wt%:PP wt%) using extruding and hot press moulding technique. From the results, it can be inferred that Bn30:PP70 mixture composite (BnPP) showed better performance among the composites prepared. For further improvement, betel nut fiber was subjected to detergent wash as well as alkali treatment for composite preparation. This work investigated the tensile strength, bending strength, tensile modulus, bending modulus, elongation at break and impact strength of the composites. Fracture morphology of the composite as well as the water absorption capacity has been monitored.  相似文献   
75.
Chronic fluoride (Fl) toxicity is a serious public health problem globally where drinking water contains more than 1 ppm of Fl. Sodium fluoride (NaF) produced male reproductive system toxicity. The aim of the present study was to evaluate the amelioration of Fl toxicity-induced fertility impairment by vitamin E and calcium during the withdrawal period. The study was carried out on 70 adult male albino rats divided into five main groups: group I control; subdivided into group Ia (maintained on standard diet and water ad libitum for 60 days) and group Ib (maintained on standard diet and water ad libitum for 120 days), group II was administered NaF and subdivided into group IIa (administered NaF for 60 day and sacrificed) and group IIb (administered NaF for 60 day then maintained on standard diet and water ad libitum for a further 60 days), and treated groups III, IV, and V were administered NaF. Rats were maintained during withdrawal from NaF, on vitamin E (10 mg kg?1 day?1 for 60 days), calcium (50 mg kg?1 day?1 orally for 60 days), and both vitamin E and calcium, respectively. The duration of NaF administration was 60 days at a dose 20 mg kg?1 day?1 for all treated groups. The following parameters were determined: body and organ weights, sperm motility, sperm morphology, sperm viability, fertility test, and hormone assays: testosterone, in vitro testosterone production, luteinizing hormone, and follicular stimulating hormone. The combined administration of vitamin E and calcium during withdrawal from NaF showed significant improvement from chronic FL-induced toxicity on male reproductive organs.  相似文献   
76.
The habit of khat chewing is widespread with a deep-rooted sociocultural tradition in these regions and as such poses a public health problem. The use of pesticides is considered to be indispensable practice for the production of adequate food supply for the increasing demands by the global population and for control of insect-borne diseases. Thus, contamination of the environment with pesticides and entry of these chemicals into the food chain is unavoidable especially in developing countries. The main objective of our current study was to assess pesticide pollution of khat leaves (unknown origin) obtained while being smuggled into the Kingdom of Saudi Arabia and to be used in Jazan area. A total of 120 khat leaf samples were extracted using solid-phase extraction followed by gas chromatography/mass spectrometry analysis for the presence of 69 standard pesticides using an internal standard, tiphenyl phosphate. No pesticide residues were detected in all the studied samples. These data as preliminary and more experiments need to be performed to confirm our present findings. Routine monitoring of the pesticide residues is important for the prevention, control, and reduction of environmental pollution and also for legal decisions to minimize health risks.  相似文献   
77.
A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively.  相似文献   
78.
The levels of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg are estimated by atomic absorption in the muscle of six commercial species of fish belonging to five freshwater lakes of Pakistan. The species included Mastacembelus armatus, Tor putitura, Mystus seenghala, Wallago attu, Catla catla and Labeo rohita. The fish were procured in comparable weight ranges so that a viable comparison of trace metal content could be effected. As, Fe, Pb, Zn and Hg showed elevated levels of 0.006–6.967, 0.933–6.133, 0.060–4.108, 0.978–5.363 and 0.030–3.211 μg/g, wet weight. The relevant statistical parameters, such as standard deviation, standard error, skewness and its t‐value are also reported for establishing the randomness of the distribution in relation to the corresponding data of freshwater lakes of the world and examined in view of species‐specificity and origin.  相似文献   
79.
A potentiometric titration technique has been used to determine the stability constants for the various complexes of Co(II) and Cu(II) with L‐asparagine and from DNA base, e.g. adenine. Stability constants of ternary systems have been evaluated by the method suggested by Irwing‐Rossotti. In addition, the conditional constants were calculated as a function of pH. The maximum values of the conditional formation constants were found to be in accordance with the mixed‐ligand complex formation constants in a determined pH region. Furthermore, the molar fractions of different species from mixed complexes were calculated by means of formation constants. The values of stability constants of mixed‐ligand complexes at 25°C are as follows: log K= 5.25 for Co(II)‐L‐asparagine‐adenine; log K= 9.30 for Cu(II)‐L‐asparagine‐adenine. The ionic strength was kept constant at I = 0.20 with NaClO4.  相似文献   
80.
A total of 96 bacterial cultures were isolated from soil. Seventeen bacterial isolates were selected following their cultivation on solid media containing 100 mg · L?1 carbofuran as the sole source of carbon and nitrogen. Of the 17 isolates, 10F, 11M, 17N, 23B and 26M were specifically chosen because of their relatively higher growth efficiency and genetic diversity based on Box-polymerase chain reaction analysis. These bacterial cultures had 16S rRNA gene sequences that were most similar to Acinetobacter baumannii (10F), Agrobacterium tumefaciens (11M), Ochrobactrum anthropi (17N), Escherichia coli (23B) and Agrobacterium tumefaciens (26M) with 97, 95, 93, 95 and 94% similarity in their 16S rDNA gene sequence, respectively. Degradation rates of carbofuran in soil inoculated with these isolates were 1.9, 1.5, 1.6, 1.7 and 1.6 times, respectively, faster in comparison with uninoculated soil after 10 days of incubation. The maximum degradation rates of carbofuran (45 and 91%) were detected in soil inoculated with A. baumannii (10F) after 10 and 20 days’ incubation, respectively. These data indicate that these isolates may have the potential for use in bioremediation of pesticide contaminated soil.  相似文献   
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