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281.
282.
A V Paniutich B I Rubika?te N N Vo?tenok E A Shidlovskaia S L Grokhovski? A L Zhuze O O Favorova 《Bioorganicheskaia khimiia》1989,15(8):1060-1069
The importance of protein phosphorylation at tyrosyl hydroxy groups in the control of cell proliferation has recently been established. For identification of tyrosine-phosphorylated proteins, monoclonal antibodies (Mabs) against artificial immunogens containing O-phosphotyrosine (pTyr) or tripeptide pTyr-Gly-Gly as haptens were generated; the haptens were coupled to carrier proteins (bovine serum albumin, human immunoglobulin, keyhole limpet hemocyanin). After immunization of mice with pTyr coupled to keyhole limpet hemocyanin, Mabs were generated which were highly specific for pTyr and did not cross-react with O-phosphoserine, O-phosphothreonine, tyrosine or nucleoside-5'-monophosphates. The Mabs specifically react with tyrosinephosphorylated proteins in the Rous sarcoma virus-transformed rat XC-cell. 相似文献
283.
E Schr?der 《Acta anatomica》1978,100(4):478-489
The utero-ovarian vascularisation of the non-pregnant rat was investigated, described and morphometrically evaluated. The ovarian and uterine arteries anastomose together giving up a ramus ovaricus. The leaving of these vessels from their main trunks varies to each body side, just as their length and width. Several segmental arteries arise from each uterine artery to the corpus uteri also side-specifically. Coiled circular arteries are found. The uterine cervical vascularisation is described separately. Different regulating effects on the function of the vessels are discussed. 相似文献
284.
D Kierek-Jaszczuk M Zurkowski E Sk?adanowska-Krzyzanowska K Tomaszewska-Guszkiewicz 《Animal blood groups and biochemical genetics》1979,10(1):15-18
Genetic variants of serum alkaline phosphatase were studied by the method of starch gel electrophoresis in the Z?otnicka Pstra breed of pigs. Two regions of alkaline phosphatase migration were observed. A single fraction in region I and four different phenotypes: AB, B, BC and BD in region II, were found. For AB, B and BC phenotypes the genetic control by three alleles AkpA, AkpB and AkpC is suggested. The observed segregation ratios in some cases deviated significantly from the expected ones. 相似文献
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288.
Calmodulin activates the ATP-dependent transport of Ca2+. The V0 value for this reaction in the absence of calmodulin is 0.82, that in the presence of 10(-7) M calmodulin is 5 times as high, i. e. 4.5 nmol 45Ca2+/mg protein/min. The Vmax value in the absence of calmodulin is 2.07, that with the activator is 4.33 nmol 45Ca2+/mg protein/min. The corresponding Km values are 0.75 X 10(-6) M and 0.66 X 10(-7) M, respectively, i. e., the affinity of the Ca-pump for Ca2+ increases. The half-maximum Ca-binding activity of calmodulin measured with a help of the fluorescent probe, N-phenyl-1-naphthylamine (PNA), is observed at 5 X 10(-7) M Ca2+. Mg2+ (3 mM) decreases 10-fold the Ca-binding affinity. No significant effect of ATP on the Ca-binding properties of calmodulin was found; the Hill coefficient is suggestive of a positive cooperativity of this reaction. A comparison of dependences of the calmodulin-stimulated component of ATP-dependent transport of Ca2+ in myometrium plasma membranes and of the Ca-binding activity of calmodulin measured with a help of PNA suggests that the effect of calmodulin on the affinity of the Ca-pump for Ca2+ can also be realized when some (but not all) Ca-binding sites in the calmodulin molecule are saturated with Ca2+. 相似文献
289.
Xiao Zhang Jinpeng Li Bo Yang Qina Leng Ji Li Xintuan Wang Junyao Lu Opeyemi Joshua Olatunji Jian Tang 《化学与生物多样性》2021,18(5):e2100065
This study investigated the protective effects of two polysaccharides (CPA-1 and CPB-2) from Cordyceps cicadae against high fructose/high fat diet (HF/HFD) induced obesity and metabolic disorders in rats. Rats were either fed with normal diet or HF/HFD and treated with CPA-1 and CPB-2 (100 and 300 mg/kg) for 11 weeks. Administration of CPA-1 and CPB-2 significantly and dose dependently reduced body and liver weight, insulin and glucose tolerance, serum insulin and glucose levels. Furthermore, serum and hepatic lipid profiles, liver function enzymes and proinflammatory cytokines (TNF-α, IL-1β and IL-6) were markedly reduced. Additionally, CPA-1 and CPB-2 treatment alleviated hepatic oxidative stress by reducing lipid peroxidation level (MDA) and upregulating glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) activities as well as ameliorated histological alterations through the reduction of hepatic lipid accumulation. These results suggested that the polysaccharides from C. cicadae showed protective effects against HF/HFD induced metabolic disturbances and may be considered as a dietary supplement for treating obesity. 相似文献
290.
Johannes Schwerk Mario K?ster Hansj?rg Hauser Manfred Rohde Marcus Fulde Mathias W. Hornef Tobias May 《PloS one》2013,8(8)
Cell lines derived from the small intestine that reflect authentic properties of the originating intestinal epithelium are of high value for studies on mucosal immunology and host microbial homeostasis. A novel immortalization procedure was applied to generate continuously proliferating cell lines from murine E19 embryonic small intestinal tissue. The obtained cell lines form a tight and polarized epithelial cell layer, display characteristic tight junction, microvilli and surface protein expression and generate increasing transepithelial electrical resistance during in vitro culture. Significant up-regulation of Cxcl2 and Cxcl5 chemokine expression upon exposure to defined microbial innate immune stimuli and endogenous cytokines is observed. Cell lines were also generated from a transgenic interferon reporter (Mx2-Luciferase) mouse, allowing reporter technology-based quantification of the cellular response to type I and III interferon. Thus, the newly created cell lines mimic properties of the natural epithelium and can be used for diverse studies including testing of the absorption of drug candidates. The reproducibility of the method to create such cell lines from wild type and transgenic mice provides a new tool to study molecular and cellular processes of the epithelial barrier. 相似文献