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61.
Environmental Science and Pollution Research - The K?z?l?rmak River is the longest river (1.355 km) in Turkey and flows into the Black Sea. Main pressures in the basin are waste...  相似文献   
62.
Many kinds of cosmetic products were analyzed to determine gross radioactivity. In this study, gross alpha/beta radioactivity concentrations in 51 cosmetic samples were determined. The examined cosmetic products consist of blusher, eye shadow, lipstick, nail polish, shampoo, hand cream, cellulite cream, baby powder, soap, and toothpaste. The gross alpha–beta activity concentrations were measured with a nuclear spectroscopic system which contains gas-flow proportional counters. The highest gross alpha/beta activity concentrations were found in eye shadow samples of 1.621Bq g?1 for alpha and 6.471Bq g?1 for beta. The total effective doses due to gross radioactivity for skin were calculated. Although the effective dose of eye shadow samples had the highest value, the effective doses due to gross radioactivity concentrations in this study were found to be lower than the radiological limits given by the authorities.  相似文献   
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Prenatal diagnosis for infantile osteopetrosis was attempted during the third pregnancy of a first-cousin marriage whose family history revealed an affected previous child. At the 25th week of pregnancy, fetal X-ray evaluation revealed marked sclerosis of osteopetrotic bone and metaphyseal splaying and clubbing of both femurs. The pregnancy was terminated and repeated X-rays and histopathological examination of fetal bone (femur) confirmed the diagnosis.  相似文献   
65.
In the fifteen-spined stickleback (Spinachia spinachia), the male alone builds a nest and provides care for the eggs until they hatch. The nest is made of filamentous algae held together with shiny secretional threads of a glycoprotein, here called tangspiggin. Tangspiggin is produced by transformed kidney cells. I investigated how tangspiggin production was related to food intake by giving males low or high food rations. Males in the high-food group produced significantly more tangspiggin than those in the low-food group. Since low food rations did not lead to a significant drop in resting metabolic rate (oxygen consumption), tangspiggin production appears to be one of the first energy-demanding processes to be dropped during food deprivation. Among males given equal food rations, females preferred to mate with those with elevated levels of tangspiggin in their nests. Tangspiggin threads may signal safety for the offspring by keeping the eggs within the nest and protecting them from egg predators. Moreover, the threads become less shiny with age, due to particle deposition, and older nests that may house older (more valuable) eggs are thereby well camouflaged. Tangspiggin provides an honest signal of male condition, acting as an extra-bodily ornament, signaling direct benefits to females or possibly also indirect benefits of "good genes" from a male who is a successful forager.  相似文献   
66.
In this study the great ramshorn snail (Planorbarius corneus), one of the most abundant gastropod of Turkish limnic systems, was investigated to determine the histopathological effects of endosulfan on the digestive gland, foot and mantle under laboratory conditions. Samples were collected from small artificial pools in Karaot at Gelendost-Isparta (southwest of Turkey), where agricultural activities are widespread. The snails were exposed to two sublethal concentrations of endosulfan (0.4 and 0.8 mg/l) for periods of 10, 20 and 30 days. Fifteen snails were kept in 2.5 l glass jars containing dechlorinated tap water and exposed under semi-static test (daily exchange of test water). All the testing was carried out on adult specimens, and snails were maintained on a photothermal period with 16 light hours at 22 +/- 2 degrees C. The histopathological examinations revealed the following changes: amoebocytes infiltration, dilatation in hemolymphatic spaces between the tubules, degeneration of cells, abnormal lumen, necrosis of cells and atrophy in the connective tissue of digestive gland; desquamation of the epithelium cells, changes in the number of mucocytes and protein gland cells, lipid vacuolus and atrophy of the columnar muscle fibers of the foot and mantle tissues. Pycnotic state of cells was also seen in the mantle tissues. Endosulfan caused significant histopathological alterations in the digestive gland, foot and mantle tissues of the snail, irrespective of concentrations of the pesticide and its exposure periods. The results are discussed, particularly in comparison to those of other aquatic organisms.  相似文献   
67.
Food and Environmental Virology - Norovirus is commonly associated with food and waterborne outbreaks. Genetic susceptibility to norovirus is largely dependent on presence of histo-blood group...  相似文献   
68.

The present study describes the application of different solid-phase extraction techniques for the extraction, separation, and quantitative determination of 10 commonly used herbicides with different chemical structures (chlorsulfuron, diuron, bentazone, linuron, chlorpropham, fenoxoprop-ethyl, MCPA, diclofop-methyl, fluazifop-butyl, trifluraline) in water. Octadecyl (C18) Empore extraction disks, octadecyl (C18), and stryene divinylbenzene (SDB) Bond Elut Env cartridges were compared for solid-phase extraction efficiency. Herbicides were separated and quantified by reversed-phase high performance liquid chromatography with diode-array detection (HPLC-DAD) with simultaneous separation on two columns of differing polarity (C18 and CN) to confirm identification. Analytical separation was performed simultaneously on C18 and CN columns. Reanalysis of the sample extracts on a (cyano) CN column were used to confirm the identity of these compounds. Method optimization and validation parameters were presented in this work. Recoveries varied from 76.0% to 99.0% for C18 disks, from 75.1% to 100.0% for C18 cartridges, and from 54.0% to 98.0% for SDB cartridges over concentrations at 0.025–0.4 μg L?1. The limits of detection were 0.012–0.035 μg L?1.  相似文献   
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The most important tool for testing seat-systems in rear impacts is a crash test dummy. However, investigators have noted limitations of the most commonly used dummy, the Hybrid III. The BioRID I is a step closer to a biofidelic crash test dummy, but it is not user-friendly and the straightening of the thoracic spine kyphosis is smaller than that 220of humans. To reduce these problems, a new BioRID prototype was developed, the P3. It has new neck muscle substitutes, a softer thoracic spine and a softer rubber torso than does the BioRID I.

The BioRID P3 was compared with volunteer test data in a rigid and a standard seal without head restraints. The dummy kinematic performance, pressure distribution between subject and seatback, neck loads and accelerations were compared with those of ten volunteers and a Hybrid III. The BioRID P3 provided repeatable test results and its response was very similar to that of the average volunteer in rear impacts at Δv = 9 km/h.  相似文献   
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