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21.
The cuticular surface of the infectious third-stage larvae of Nematospiroides dubius activates complement via the alternative pathway. Sensitisation of larvae with complement or with antibodies from the serum of immune mice (resistant to reinfection) promoted the adherence of mouse peritoneal exudate cells to the larval cuticle during incubation in vitro. The infectivity of larvae sensitized with antibody or complement was significantly reduced after incubation with cells from immune mice.  相似文献   
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Despite continuing debates around cytoreductive surgery in malignant gliomas, there is broad consensus that increased extent of tumor reduction improves overall survival. However, maximization of the extent of tumor resection is hampered by difficulty in intraoperative discrimination between normal and pathological tissue. In this context, two established methods for tumor visualization, fluorescence guided surgery with 5-ALA and intraoperative MRI (iMRI) with integrated functional neuronavigation were investigated as a dual intraoperative visualization (DIV) approach. Thirty seven patients presumably suffering from malignant gliomas (WHO grade III or IV) according to radiological appearance were included. Twenty-one experimental sequences showing complete resection according to the 5-ALA technique were confirmed by iMRI. Fourteen sequences showing complete resection according to the 5-ALA technique could not be confirmed by iMRI, which detected residual tumor. Further analysis revealed that these sequences could be classified as functional grade II tumors (adjacent to eloquent brain areas). The combination of fluorescence guided resection and intraoperative evaluation by high field MRI significantly increased the extent of tumor resection in this subgroup of malignant gliomas located adjacent to eloquent areas from 61.7% to 100%; 5-ALA alone proved to be insufficient in attaining gross total resection without the danger of incurring postoperative neurological deterioration. Furthermore, in the case of functional grade III gliomas, iMRI in combination with functional neuronavigation was significantly superior to the 5-ALA resection technique. The extent of resection could be increased from 57.1% to 71.2% without incurring postoperative neurological deficits.  相似文献   
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This study was conducted to determine the effects of methionine, inositol and carnitine on sperm (motility, abnormality, DNA integrity and in vivo fertility) and oxidative stress parameters (lipid peroxidation, total glutathione and antioxidant potential levels) of bovine semen after the freeze–thawing process. Nine ejaculates, collected with the aid of an artificial vagina twice a week from each Simmental bovine, were included in the study. Each ejaculate, splitted into seven equal groups and diluted in Tris-based extender containing methionine (2.5 and 7.5 mM), carnitine (2.5 and 7.5 mM), inositol (2.5 and 7.5 mM) and no additive (control), was cooled to 5 °C and then frozen in 0.25 ml straws. Frozen straws were then thawed individually at 37 °C for 20 s in a water bath for the evaluation.The extender supplemented with 7.5 mM doses of carnitine and inositol led to higher subjective motility percentages (61.9 ± 1.3% and 51.3 ± 1.6%) compared to the other groups. The addition of methionine and carnitine at doses of 2.5 and 7.5 mM and inositol at doses of 7.5 mM provided a greater protective effect in the percentages of total abnormality in comparison to the control and inositol 2.5 mM (P < 0.001). As regards CASA motility, 7.5 mM carnitine (41.6 ± 2.9% and 54.2 ± 4.9%) and inositol (34.9 ± 2.0% and 47.3 ± 2.2%) caused insignificant increases in CASA and total motility in comparison to the other groups. All of the antioxidants at 2.5 and 7.5 mM resulted in lower sperm with damaged DNA than that of control, thus reducing the DNA damage (P < 0.05). No significant differences were observed in CASA progressive motility and sperm motion characteristics among the groups. In fertility results based on 59-day non-returns, no significant differences were observed in non-return rates among groups. As regards biochemical parameters, supplementation with antioxidants did not significantly affect LPO and total GSH levels in comparison to the control group (P > 0.05). The maintenance of AOP level in methionine 2.5 mM was demonstrated to be higher (5.06 ± 0.38 mM) than that of control (0.96 ± 0.29 mM) following the freeze–thawing (P < 0.001). Supplementation with these antioxidants prior to the cryopreservation process protected the DNA integrity against the cryodamage. Furthermore, future research should focus on the molecular mechanisms of the antioxidative effects of the antioxidants methionine, carnitine and inositol during cryopreservation.  相似文献   
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A comparison of random amplified polymorphic DNA (RAPD) was used to investigate genetic polymorphisms among 25 isolates of Giardia intestinalis and to assess the utility of RAPD for subtype detection and genealogical analysis. Using data obtained for six human and 19 animal-derived isolates in polymerase chain reactions using 13 different primers, phylogenetic trees were constructed and bootstrap values computed by the program FreeTree. Three major clades were distinguished, corresponding to previously defined genetic assemblages A, B, and E. The purported specificity of assemblage E genotypes for artiodactyl hosts was supported. Assemblages A and B showed wide host spectra, including human and animal hosts. No correlation was found between the genotype of analyzed isolates and the presence or absence of the double-stranded RNA Giardiavirus. The results indicate that RAPD data provide reliable genetic information that can be used for both "fingerprinting" and genealogical purposes.  相似文献   
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Demir  Ahmet U.  Ardic  Sadik  Firat  Hikmet  Karadeniz  Derya  Aksu  Murat  Ucar  Zeynep Zeren  Sevim  Serhan  Ozgen  Fuat  Yilmaz  Hikmet  Itil  Oya  Peker  Yuksel  Aygul  Fatma  Kiran  Sibel  Gelbal  Selahattin  Cepni  Zafer  Akozer  Mehmet 《Sleep and biological rhythms》2015,13(4):298-308
Sleep and Biological Rhythms - Sleep disorders constitute an important public health problem. Prevalence of sleep disorders in Turkish adult population was investigated in a nationwide...  相似文献   
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The preservation of many stained gross specimens in solution creates some difficulties. It is convenient and effective to preserve material in polyester resin instead of glycerol. The aim of this study was to determine the usefulness of clearing and embedding using polyester resin. The samples consisted of the nerve distribution patterns of skeletal muscles stained using Sihler's method. The muscles were cleared more successfully and the intramuscular nerve distributions were demonstrated better in polyester than in glycerol. The method presented here eliminates not only the storage and handling problems of specimens, but also problems such as pale stains and the molding of preparations. Furthermore, it is more convenient to examine and to photograph specimens cleared and embedded in polyester than those stored in glycerol.  相似文献   
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Two new alkaloid N-oxides, 1-O-acetyldihydromethylpseudolycorine N-oxide, and 11-hydroxyvittatine N-oxide, ten known alkaloids; arolycoricidine, haemanthamine, O-methylnorbelladine, narcidine, dihydrolycorine, 8-O-demethylmaritidine, stylopine and protopine, nicotinic acid and tyramine were isolated from Galanthus trojanus A.P. Davis & N. Özhatay (Amaryllidaceae). The chemical structures of the isolates were elucidated by UV, IR, MS, CD, 1D and 2D NMR experiments. The in vitro antiprotozoal and cytotoxic potentials of the compounds were also evaluated.  相似文献   
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