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931.
Akihito TAKAHASHI Ajalli RAHIM Miki TAKEUCHI Emiko FUKUI Midori YOSHIZAWA Kuniaki MUKAI Makoto SUEMATSU Hidetoshi HASUWA Masaru OKABE Hiromichi MATSUMOTO 《The Journal of reproduction and development》2016,62(1):43-49
Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1]
or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted
to extraembryonic regions during the postimplantation period and detected marked expression in mouse
Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the
postimplantation period, suggesting that it plays a physical and physiological role in embryo development
and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to
determine the role of Tinagl1 during embryonic development and pregnancy, we generated
Tinagl1-deficient mice. Although Tinagl1–/– embryos were not
lethal during development to term, homologous matings of Tinagl1–/– females and
Tinagl1–/– males showed impaired fertility during pregnancy, including failure
to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with
equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did
not differ between Tinagl1–/– and Tinagl1flox/flox.
In vitro fertilization followed by embryo culture also demonstrated the normal
developmental potential of Tinagl1-null embryos during the preimplantation period. Our
results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and
they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1
is related to fertility in adult females but is not essential for either fertilization or preimplantation
development in vitro. 相似文献
932.
Effects of different dl‐selenomethionine and sodium selenite levels on growth performance,immune functions and serum thyroid hormones concentrations in broilers 下载免费PDF全文
This trial was conducted in a 2 × 3 + 1 factorial arrangement based on a completely randomized design to evaluate the effects of different dl ‐selenomethionine (dl ‐Se‐Met) and sodium selenite (SS) levels on growth performance, immune functions and serum thyroid hormones concentrations in broilers. A total of 840 Ross 308 broilers (7 days old) were allocated by body weight to seven treatments (three replicates of 40 birds each treatment) including (1) basal diet (containing 0.04 mg of selenium (Se)/kg; control) without supplementary Se; (2, 3 and 4) basal diet + 0.05, 0.15 or 0.25 mg/kg Se as SS; (5, 6 and 7) basal diet + 0.05, 0.15 or 0.25 mg/kg Se as dl ‐Se‐Met. The experiment lasted 42 days. The results revealed that dietary Se supplementation improved (p < 0.05) average daily gain, feed efficiency, immune organ index, serum immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM) and triiodothyronine (T3) concentrations and decreased (p < 0.01) thyroxine (T4)/T3 ratio in serum compared with the control. Broilers receiving the dl ‐Se‐Met‐supplemented diets had higher (p < 0.05) feed efficiency, thymus index, the amounts of IgA, IgG, IgM and T3 as well as lower (p < 0.05) serum T4 concentrations and T4/T3 ratio than those consuming the SS‐supplemented diets. Serum IgA and IgM levels of broilers fed 0.15 mg Se/kg were significantly higher (p < 0.05) than those of broilers fed 0.05 or 0.25 mg Se/kg. In summary, we concluded that dl ‐Se‐Met is more effective than SS in increasing immunity and promoting conversion of T4 to T3, thus providing an effective way to improve the growth performance of broilers. Besides, based on a consideration of all experiment indices, 0.15 mg Se/kg was suggested to be the optimal level of Se supplementation under the conditions of this study. 相似文献
933.
934.
以四川松口蘑(Tricholoma matsutake)代表性主产区菌塘土壤及新鲜子实体为材料,分析菌塘土壤理化性质和子实体的营养品质,利用冗余分析(redundancy analysis,RDA)研究前者对后者的影响.结果表明:调查样点菌塘土壤理化性质差异较大,总体以砂粒为主(50.2%~88.5%),质地较为疏松,pH总体呈弱酸性(5.08~7.26),有机质含量54.8~189.6 g/kg;调查样点松口蘑子实体营养品质总体较好,其中谷氨酸含量较高(2.27%~4.10%),但地区间差异较大;钙含量较高(124.4~725.1 mg/kg),锌和锰含量中等,铜含量较低;冗余分析结果表明,子实体中营养品质与菌塘土壤中交换性锰(TMn)含量极显著正相关(P<0.01).菌塘土壤中TMn是影响松口蘑子实体关键的土壤理化因子. 相似文献
935.
DB102为一田间发现的三倍体水稻,利用它做母本与二倍体水稻中作59杂交,得到一个早世代(F2)稳定群体,通过微卫星分析发现,该群体中有一些微卫星位点发生了杂合性丧失,且至少6条染色体上发生微卫星位点杂合性丧失(loss of heterzygoisity LOH)可能有DNA序列变化。而微卫星位点的杂合性丧失又可能与该杂交组合早世代稳定有关。 相似文献
936.
Corfield GS Read RA Eastley KA Richardson JL Robertson ID Day R 《Australian veterinary journal》2007,85(6):212-216
Hip palpation has been used to provide semiquantitative information regarding passive joint laxity and susceptibility to hip dysplasia. The purpose of this study was to: (1) evaluate the intra- and inter-examiner repeatability of the hip reduction angle measured at 4 months of age by three examiners using manual goniometry and an electromagnetic tracking system; (2) compare the hip reduction angle measured with manual goniometry to the hip reduction angle measured with the electromagnetic tracking system; and (3) evaluate the hip reduction angle, distraction index and Ortolani manoeuvre at 4 months of age as predictors of the development of hip osteoarthritis at 12 months of age in 11 Labrador Retriever dogs. Intra- and inter-examiner repeatability was demonstrated for both the manual and electromagnetic goniometric measurement of the hip reduction angle (coefficient of variation < 4.3% and < 6.1%; and P = 0.163 and P = 0.836 respectively). The hip reduction angle measured by manual goniometry was moderately correlated to the hip reduction angle measured by the electromagnetic tracking system (r = 0.603, P < 0.0000). The hip reduction angle measured by manual and electromagnetic goniometry was a poor predictor of osteoarthritis at 12 months of age (r = 0.231, P < 0.062, and r = 0.321, P < 0.01). The distraction index was moderately correlated with the development of osteoarthritis by 12 months of age (r = 0.493, P < 0.0000). The Ortolani sign was sensitive (100%) but not specific (41%) for the development of osteoarthritis at 12 months of age. The hip reduction angle did not further quantify the Ortolani manoeuvre as a predictor of osteoarthritis in Labrador Retrievers. 相似文献
937.
Ghrelin, acts as the endogenous ligand for growth hormone secretagogues receptor (GHS-R), is a novel growth hormone (GH) releasing peptide with reported effects on food intake in chickens. In this study, an 8 bp indel polymorphism in exon 1 of the chicken Ghrelin (cGHRL) gene was genotyped in a F(2) designed full-sib population to analyze its associations with chicken growth and carcass traits. Later, mRNA level in the proventriculus was determined by real-time PCR to reveal the expression feature of cGHRL gene. Result showed that this 8 bp indel was significantly associated with body weight at the age of 28 days (BW28) and 56 days (BW56), eviscerated weight (EW) and leg muscle weight (LMW) (P<0.05), highly significantly associated with hatch weight (HW), BW14, 21, 35, 42, 49, 90 and body length (BL), dressed weight (DW), eviscerated weight with giblet (EWG), wing weight (WW), breast muscle weight (BMW) and head and neck weight (HNW) (P<0.01). Meanwhile, A allele (with 'CTAACCTG') was positive for chicken growth as individuals with AA genotype had the highest value of all traits. Analysis on cGhrelin mRNA level revealed that it differed significantly among individuals with three genotypes (P<0.05). Individuals with AB genotype had the highest mRNA level, whereas that of AA had the lowest one. It was concluded that this 8 bp indel of cGHRL gene was significantly associated with most body weight and body composition traits, and negative effect of endogenous Ghrelin on chicken growth were indicated by this study. 相似文献
938.
Hoffman AM Oura TJ Riedelberger KJ Mazan MR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):184-192
BACKGROUND: Horses with recurrent airway obstruction (heaves) are described as exhibiting "increased abdominal effort," but it is unknown whether this translates to an effective contribution to ventilation. HYPOTHESIS: We hypothesized that heaves is characterized by asynchrony between rib cage and abdominal motions, and that the abdominal component is the major contributor to ventilation. ANIMALS: The rib cage versus abdominal motion in naturally occurring heaves (n = 15) was compared to controls at rest (n = 7) and during hyperpnea because of lobeline treatment, and the effects of histamine-induced bronchoconstriction in controls (n = 10). METHODS: Flow patterns, phase angle (theta) between the rib and abdominal compartments, abdominal (Vabd) contribution to tidal volume (VT), and lung mechanics were measured. RESULTS: Findings unique to the heaves group included the loss of biphasic expiratory flow, severely increased theta with the abdomen consistently lagging behind the rib cage, and a reduced contribution of the abdomen to ventilation. A subgroup of heaves (n = 5) with abdominal paradox showed a significant (P < .05) reduction in tidal volume, and increased respiratory rate. Bronchodilation reduced theta in heaves (P = .06), but theta remained significantly higher after bronchodilation than found in controls. CONCLUSIONS AND CLINICAL IMPORTANCE: We conclude that breathing pattern in horses with heaves is characterized by severe rib cage/abdominal asynchrony, with the rib cage motion in synchrony with flow, therefore dominating ventilation. In a subset of heaves, the abdominal compartment (diaphragm, abdominal muscles) was completely out of synchrony with flow ("abdominal paradox") despite the clinical appearance of "increased abdominal effort." 相似文献
939.
940.
红三叶多酚氧化酶特性的研究 总被引:1,自引:0,他引:1
红三叶(Trifolium pretense L.)多酚氧化酶仅作用于邻苯酚,与对苯酚、间苯酚和一元酚无作用,而且对不同的邻苯酚其活性也表现很大差异,其中以咖啡酸作底物时活性最大.红三叶多酚氧化酶反应的最适pH值为6.5~7.0,最适温度为25~30℃,50℃时热稳定性相对较好. 相似文献