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21.
  1. The Euphrates softshell turtle (Rafetus euphraticus) is the most threatened chelonian species in the Middle East, where it is endemic to the Tigris and Euphrates basins. Since the ecology of this species is little known, it is difficult to plan any reliable action for its correct management and conservation.
  2. To enhance the scientific knowledge on R. euphraticus, and to establish a science-based management strategy, a detailed investigation was undertaken on the distribution, habitat, activity and home range of R. euphraticus in Turkey. The previous distribution records in Turkey are for the 1990s; thus, this study is the first comprehensive field research on the species after nearly 3 decades.
  3. There was a significant sexual size dimorphism in the Turkish population, with males larger than females.
  4. Four individuals were radiotracked for 1 year. The mean home range was highly variable depending on how it was calculated, but that of males was considerably greater than that of females by all methods used.
  5. A quantitative evaluation was made of habitat change with time. The land cover classes potentially available to turtles in the Euphrates River basin increased by more than 100% between the 1990s and 2018: 92% of this enhancement was derived from water bodies and coastal lands.
  6. Fifteen dams have been built in the lower part of the basins in the last 30 years. In addition, continuing human interactions have caused the fragmentation or destruction of suitable habitats for R. euphraticus.
  7. The factors threatening R. euphraticus were assessed and a conservation action plan was developed. Some objectives such as monitoring and creating awareness of this action plan have been met while others are still waiting to be achieved.
  相似文献   
22.
In order to evaluate the influence of different N rates on percent N derived from fertilizer (%Ndff) at different growth stages, on yields and the percent N use efficiency (%NUE) values of two winter wheat varieties (durum and bread), field experiments on fallow were carried out at four different locations in Central Anatolia, in the 1991–1992 and 1992–1993 growing seasons. At each site the rates of N (0, 40, 80 and 120?kg N/ha) were applied as ammonium sulphate [(NH4)2SO4] using a Latin Square experimental design with four replicates. The total amounts of N fertilizer were applied once after seedling emergence at all experimental sites. Labelled (15NH4)2SO4 fertilizer was applied to sub-plots from which %Ndff values were determined at tillering, booting, grain filling, and harvest stages. Yield sub-plots received unlabelled (NH4)2SO4 from which total dry matter (seed and straw) and N yields were determined. Also the %NUE values were calculated by the 15N and "difference" methods at the harvest stage. Stored soil moisture at 0–90?cm depth, evapotranspiration and water use efficiency values were calculated as well. The results obtained showed that (1) Gerek-79 variety used both the applied N fertilizer and the available soil moisture more efficiently, (2) the percent NUE values obtained overall were generally less than 20 for both varieties and (3) with the 15N method, less variable %NUE values were obtained in comparison to the difference method.  相似文献   
23.
To utilize lupin seeds for food and pharmaceutical applications, lupin seeds were pretreated to remove oil using hexane or carbon dioxide. Two types of lupin protein isolate were prepared. Both types of protein isolate showed good foaming activity, comparable to egg white. Protein isolate extracted under acid conditions showed higher foaming activity than protein isolate extracted at neutral pH. The lipoxygenase activity was much reduced in both of the protein isolates. The protein isolate extracted at neutral pH showed a stronger angiotensin converting enzyme inhibition than the protein isolate extracted under acidic pH. In contrast, the protein isolate extracted under acid conditions had a greater sodium cholate binding capacity, comparable to that of cholestyramine. Lupin samples showed less DPPH radical scavenging activity than deoiled soybean. The deoiling method did not affect the functional properties, lipoxygenase activity, angiotensin converting enzyme inhibition, sodium cholate binding, and radical scavenging activity.  相似文献   
24.
The overall sex ratio of offspring (dead embryos and hatch chicks) from all the fertilized eggs of 140 hens collected for 30 days was studied using duplex PCR of certain fragments of sex chromosomes. Additional 894 dead embryos over a period of 21 days of incubation were also investigated to verify the sex ratio of the dead embryos. The sex of the early dead embryos was identified using this molecular sexing technique. The sex ratio of the hatch chicks and the total offspring of the hens investigated in this experiment did not differ from the expected sex ratio (i.e., 1:1)., However, the number of female dead embryos was significantly more than that of males. The data indicated that the different physiologic function of males and females contributed to female-biased mortality during incubation. It was also found by further analysis that the sex ratios of the offspring of some hens were significantly biased to female or male over the period investigated, which suggested that the sex ratio of offspring might be influenced by the maternal condition to some degrees.  相似文献   
25.
Meiosis is a critical stage of gametogenesis in which alignment and synapsis of chromosomal pairs occur, allowing for the recombination of maternal and paternal genomes. Here we show that FK506 binding protein (Fkbp6) localizes to meiotic chromosome cores and regions of homologous chromosome synapsis. Targeted inactivation of Fkbp6 in mice results in aspermic males and the absence of normal pachytene spermatocytes. Moreover, we identified the deletion of Fkbp6 exon 8 as the causative mutation in spontaneously male sterile as/as mutant rats. Loss of Fkbp6 results in abnormal pairing and misalignments between homologous chromosomes, nonhomologous partner switches, and autosynapsis of X chromosome cores in meiotic spermatocytes. Fertility and meiosis are normal in Fkbp6 mutant females. Thus, Fkbp6 is a component of the synaptonemal complex essential for sex-specific fertility and for the fidelity of homologous chromosome pairing in meiosis.  相似文献   
26.
Purpose To describe a case of superficial keratomycosis caused by Mortierella wolfii (M. wolfii) in a horse. Methods A thoroughbred filly was presented with painful right eye of 2 days’ duration. A superficial corneal ulcer was observed ventrally together with multifocal punctuate opacities axially. Samples were collected by swabbing and scraping the ulcerated lesion and submitted for microbiologic and cytologic examination. Results Microscopic evaluation of debrided corneal tissue revealed the presence of nonseptate fungal hyphae, and culture of a corneal swab yielded fungal growth. Medical treatment with topical antifungal, antibiotic and autogenous serum and systemic anti‐inflammatory resolved the problem within 2 weeks. Conclusions Cytologic evaluation of a corneal scraping was useful to make a clinical diagnosis of keratomycosis. Based on the mycological characteristics, the fungus isolated from the corneal lesion was identified as M. wolfii. To the authors’ knowledge, this is the first case report of equine keratomycosis associated with this fungus, although the organism is known to infect various organs of cattle.  相似文献   
27.
This study examined the effects of chlorpyrifos in the rat erythrocyte antioxidant system and evaluated the ameliorating effects of catechin and quercetin on the oxidative damage induced by chlorpyrifos. Sexually mature male Wistar rats were given chlorpyrifos (5.4 mg/kg, 1/25 of the oral LD50), catechin (20 mg/kg), quercetin (20 mg/kg), catechin plus chlorpyrifos, and quercetin plus chlorpyrifos daily via gavage for four weeks. No statistical differences were found in the catechin-only and quercetin-only groups compared with the control group. By the end of the fourth week, chlorpyrifos alone increased the levels of malondialdehyde (MDA) and decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities compared with the control group in rat erythrocytes. In the catechin-plus-chlorpyrifos and quercetin-plus-chlorpyrifos groups, there were statistically significantly decreased MDA levels and increased SOD, CAT, and GPx activities compared with the chlorpyrifos-only group. Thus, it appears that catechin and quercetin ameliorate chlorpyrifos-induced oxidative stress in rat erythrocytes in vivo.  相似文献   
28.
Roles of sulfhydryl groups on thermal aggregation of beta-lactoglobulin A (betaLG A) at pH 7.5 were investigated. It is known that betaLG A modified at Cys(121) with N-ethylmaleimide (NEM-betaLG A) does not form an aggregate by heating and that dithiothreitol (DTT) reduces cystine residues and induces the intermolecular sulfhydryl/disulfide interchange reaction and/or oxidation. NEM-betaLG A was heated in the presence of DTT. The molecules were linked together with an intermolecular disulfide bridge, and the polymer formed increased with increase in DTT concentration. The largest portion of polymer was formed when DTT was added at around the same molar concentration as that of NEM-betaLG A. Then, polymer formation decreased with further increase in DTT concentration. The results suggest that sulfhydryl/disulfide residues other than Cys(121), generated from cysteine residues, can induce intermolecular sulfhydryl/disulfide interchange reactions to polymer and that thiol compounds, for example, added DTT, are capable of starting such reactions.  相似文献   
29.
Koji Wada  Takaharu Kawano   《Geoderma》1978,20(3-4):215-224
Use of Jeffries acid-oxalate treatment in particle-size analyses of Ando soils for breaking up the sand- and silt-size aggregates bound by allophane, allophane-like constituents and hydrous iron oxides was studied. The analyses by this method and those by a method using sonic-wave oscillation were compared for nine Ando soil samples having different clay-mineral compositions and organic-matter contents. There were minor differences in the sand contents between the two analyses, but the clay contents were higher and the silt contents were lower after Jeffries acid oxalate treatment.

Characterization of the silt-size separates by an X-ray powder method, water vapor adsorption and electron microscopy indicated that the lower silt contents after Jeffries acid oxalate treatment were mainly due to dissolution of allophane and allophane-like constituents, whereas the silt-size separates after sonic-wave treatment still contained these mineral constituents. The proposed procedure for particle-size analysis was also useful for two ferruginous soils representing the Hydrandept and Torrox.  相似文献   

30.
Thin-layer isoelectric focusing was applied to the identification of whale (Cetacea) species by using water-soluble sarcoplasmic proteins of skeletal muscles. Twenty-eight samples consisting of 4 species (10 samples) of baleen whales (Mysticeti) and 8 species (18 samples) of toothed whales (Odontoceti) were analyzed. Each sample (approximately 1 g) was electrophoresed with Ampholine PAGplate, pH 3.5-9.5. The electrophoretic profiles were species-specific on the 4 toothed whale species that did not have a marked intra-species difference, and all 4 baleen whale species. However, the profiles were not specific on the 4 other dolphin species, even though they were discriminable from the other 4 toothed whale species. Numerical values of pIs and relative peak heights were obtained by densitometric analysis of the isoelectro-focused protein bands. The bands were also species-specific for the 8 toothed whale species mentioned. The values may be applicable to species identification without the need for a standard sample, which may not be readily obtainable. Experiments on test samples of minke and sel whales showed that bloodletting with ice water made the densities of isoelectro-focused bands thinner, although species identification was still possible by using the inside part of muscles. Heat treatment at below 60 degrees C for 10 min caused little denaturation; at higher temperatures the protein bands were diminished in a temperature-dependent fashion. Therefore, the present isoelectric focusing analysis should be applicable to small samples of whale meat, excluding several species of dolphins.  相似文献   
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