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91.
We assessed the size of the population of the African Softshell Turtle, Trionyx triunguis, in Dalaman (Mu?la, Turkey), which is considered to be the largest population of the species in the Mediterranean, by using the Jolly-Seber mark-recapture method. A total of 415 individuals were caught during the summer months of 2009 to 2011, of which 148 were recaptures. From 267 marked individuals, 148 (55%) were male, 69 (26%) were female and 50 (19%) were juveniles and subadults of indeterminate sex. The male:female ratio was calculated to be 2.14:1. By using Model A' of the Jolly-Seber mark-recapture method, which includes deaths but no immigration, the mean population size in Kükürt and Küçükdalyan (Karg?n) lakes, together with Tersakan and Ta?l?çay creeks, were estimated to be 396±36. Based on this estimation, the population density was calculated to be 14 turtles/ha. Approximately 67.4% of the estimated population was marked. The mean capture probability (p) and mean survival ratio (Φ) were 0.094±0.009 and 0.957±0.076, respectively. Our results showed that the species’ population size is larger than previously estimated based on visual counts. The status “Vulnerable” C2a of the IUCN Red Data Book categories seems therefore more appropriate for the Mediterranean subpopulation of Trionyx triunguis than “Endangered” C2a. 相似文献
92.
93.
Taíse F. Pedroso Cláudia S. Oliveira Mariana M. Fonseca Vitor A. Oliveira Maria Ester Pereira 《Biological trace element research》2017,180(2):275-284
This study investigated the toxicity of rats exposed to lead acetate (AcPb) during the second phase of brain development (8–12 days postnatal) in hematological and cerebral parameters. Moreover, the preventive effect of zinc chloride (ZnCl2) and N-acetylcysteine (NAC) was investigated. Pups were injected subcutaneously with saline (0.9% NaCl solution), ZnCl2 (27 mg/kg/day), NAC (5 mg/kg/day) or ZnCl2 plus NAC for 5 days (3rd–7th postnatal days), and with saline (0.9% NaCl solution) or AcPb (7 mg/kg/day) in the five subsequent days (8th–12th postnatal days). Animals were sacrificed 21 days after the last AcPb exposure. Pups exposed to AcPb presented inhibition of blood porphobilinogen-synthase (PBG-synthase) activity without changes in hemoglobin content. ZnCl2 pre-exposure partially prevented PBG-synthase inhibition. Regarding neurotoxicity biomarkers, animals exposed to AcPb presented a decrease in cerebrum acetylcholinesterase (AChE) activity and an increase in Pb accumulation in blood and cerebrum. These changes were prevented by pre-treatment with ZnCl2, NAC, and ZnCl2 plus NAC. AcPb exposure caused no alteration in behavioral tasks. In short, results show that AcPb inhibited the activity of two important enzymatic biomarkers up to 21 days after the end of the exposure. Moreover, ZnCl2 and NAC prevented the alterations induced by AcPb. 相似文献
94.
Additional vertebrates and ostracods from the bituminous shale of the Khao Loc Formation at Tong Vai, Ha Giang Province, northern Vietnam, corroborate its correlation with the upper part of the Xishancun (Xiaxishancun) Formation and the lower part of the Xitun and Lianhuashan formations of South China, and its Middle to Late Lochkovian age. The variations in morphology and ornamentation of the galeaspid Polybranchiaspis liaojaoshanensis from Tong Vai are discussed and regarded as possibly size and growth-related. A new acanthothoracid placoderm with a very deep dorsal process is described from Tong Vai and the specific distinction between the antiarchs Minicrania lissa from Tong Vai and M. lirouyii from Yunnan is supported by additional characters. Petalichthyid placoderms are recorded from this locality for the first time, and the skull of a juvenile youngolepidid sarcopterygian is described. Eurypterid fragments and a phyllocarid crustacean are also recorded from the Khao Loc Formation. A new species of the chonetid brachiopod genus Tulynetes, endemic to northern Vietnam, is described from the Pragian Mia Le Formation at Cu Le, Bac Kan Province, a new locality which yields a large diversity of taxa with outstanding preservation. 相似文献
95.
Nedea E Nalbant D Xia D Theoharis NT Suter B Richardson CJ Tatchell K Kislinger T Greenblatt JF Nagy PL 《Molecular cell》2008,29(5):577-587
Glc7, the yeast protein phosphatase 1, is a component of the cleavage and polyadenylation factor (CPF). Here we show that downregulation of Glc7, or its dissociation from CPF in the absence of CPF subunits Ref2 or Swd2, results in similar snoRNA termination defects. Overexpressing a C-terminal fragment of Sen1, a superfamily I helicase required for snoRNA termination, suppresses the growth and termination defects associated with loss of Swd2 or Ref2, but not Glc7. Suppression by Sen1 requires nuclear localization and direct interaction with Glc7, which can dephosphorylate Sen1 in vitro. The suppressing fragment, and in a similar manner full-length Sen1, copurifies with the snoRNA termination factors Nrd1 and Nab3, suggesting loss of Glc7 from CPF can be compensated by recruiting Glc7 to Nrd1-Nab3 through Sen1. Swd2 is also a subunit of the Set1c histone H3K4 methyltransferase complex and is required for its stability and optimal methyltransferase activity. 相似文献
96.
Borrelia burgdorferi infection is the most frequent tick-transmitted disease worldwide. Our aim was to assess the seroprevalence of B. burgdorferi infection among forestry workers and farmers in Duzce, in the north-west region of Turkey. Blood samples from 349 forestry workers and farmers and 193 healthy blood donors were obtained to determine the presence of antibodies to B. burgdorferi. A two-step testing strategy was used; the sera were initially tested by ELISA and then by Western blot (WB) IgG. Demographic data regarding residence, age, gender, profession, tick bite history, contact with animals, and symptoms involving the skin, nervous system, and osteoarticular system were collected by questionnaire. All results were evaluated statistically using the chi2 test. The seroprevalence of B. burgdorferi was 10.9% (n=38) in forestry workers and farmers and 2.6% (n=5) in blood donors by ELISA, with a statistically significant difference (p<0.001). Seropositivity rates were related to age, gender, and common risk factors for the disease. IgG seropositivity was confirmed in four (1.1%) sera by WB. In this first seroepidemiological report from the northwest region of Turkey, tick bite exposure was found to be high, whereas B. burgdorferi infection was not common. Preventive measures against tick exposure and further studies to determine the distribution of Lyme disease in Turkey are proposed. 相似文献
97.
The aim of this study was to design and evaluate of mucoadhesive gel formulations for the vaginal application of clomiphene
citrate (CLM) for local treatment of human papilloma virus (HPV) infections. Chitosan (CHI) and polycarbophil (PC) were covalently
modified using the thioglycolic acid and L-cysteine, respectively. The formation of thiol conjugates of chitosan (CHI-TG)
and polycarbophil (PC-CYS) were confirmed by FT-IR analysis and PC-CYS and CHI-TG were found to have 148.42 ± 4.16 and 41.17 ± 2.34 μmol
of thiol groups per gram of polymer, respectively. One percent CLM gels were prepared by combination of various concentrations
of PC and CHI with thiolated conjugates of these polymers. Hardness, compressibility, elasticity, adhesiveness and cohesiveness
of the gels were measured by Texture profile analysis and the vaginal mucoadhesion was investigated by mucoadhesion test.
The increasing in the amount of the thiol conjugates was found to enhance the elasticity, cohesiveness, adhesiveness and mucoadhesion
of the gel formulations but not their hardness and compressibility when compared to gels prepared using their respective parent
formulations. Slower release rate of CLM from gels was achieved when the polymer concentrations were increased in the gel
formulations. PC and its thiol conjugate were found to prolong the release of CLM longer than 70 h unlike gel formulations
prepared using CHI and its thiol conjugate which were able to release CLM up to 12 h. Stability of CLM was preserved during
the 3 month stability analysis under controlled room temperature and accelerated conditions. 相似文献
98.
99.
Rong Huei Chen Wei Yu Chen Shang Ta Wang Chu Hsi Hsu Min Lang Tsai 《Carbohydrate polymers》2009,78(4):902-907
The objective of this study is to explore the cause(s) of changes in the hydrodynamic volume of chitosan molecules in solutions of different organic acids, at different temperatures and ionic strengths. Change in intrinsic viscosity is used as the parameter to elucidate the causes of changes in the hydrodynamic volume of chitosan molecules in these solutions. Results show that the intrinsic viscosity of chitosan decreases in acetic acid or in malic acid over storage time. These decreases are more pronounced in acetic acid solution than in malic acid solution, more significant in higher temperature than in lower temperature solutions, and greater in solutions without NaCl than in solutions containing higher NaCl. The decrease in intrinsic viscosity can perhaps be attributed to the compounded effects of compaction of the chitosan molecules and/or acidic degradation during storage. 相似文献
100.
Emilia Brzosko Ada Wróblewska Izabela Tałałaj Wojciech Adamowski 《Folia Geobotanica》2009,44(2):131-144
For evolutionary and ecological analyses, genetic diversity at different scales needs to be studied in terms of biological properties, habitat, population size and population history. We surveyed Platanthera bifolia populations from six regions in northeastern Poland to determine the impact of the mating system and population history on genetic diversity. Based on variation at allozyme markers, genetic variation was relatively moderate (P?=?22.3%, A?=?1.48, H O?=?0.083, F IS?=??0.015) and similar to other Platanthera species. These parameters varied between populations (P?=?13.3%–26.6%, A?=?1.26–1.66, H O?=?0.055–0.111, F IS?=??0.262–0.147). The genetic diversity patterns were shaped by different proportions of facilitated selfing and/or outcrossing, resulting in positive and negative F IS values, respectively. No relationship between inbreeding coefficient and population size, however, and no impact of apomixis on the level of genetic diversity of P. bifolia were found. The relatively low level of genetic differentiation among the investigated regions (F CT?=?0.002, P?>?0.05) and among populations (F ST?=?0.048, P?<?0.001), and the lack of a significant relationship between genetic and geographical distance, are discussed in the context of possible scenaria of postglacial expansion. 相似文献