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991.
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In this study we treated the handmade cloned (HMC) buffalo embryos with the DNA methylation inhibitors; 5-aza-2′-deoxycytidine (AzadC) or Zebularine individually after post-fusion and during in vitro culture till eighth day. The blastocysts production rate significantly improved (p < .01) after treating embryos independently with 5 nM AzadC and 5 nM zebularine compared with 2 and 10 nM AzadC or zebularine groups, respectively. The highest cleavage rates were obtained for 5 nM treatment of AzadC and zebularine compared with other treatments and untreated control group. Quality of blastocysts were evaluated using total cell number (TCN) and the ratio of number of inner cell mass (ICM) cells/total cell number (ICM/TCN). Zebularine treatments (2/5/10 nM) significantly improved both TCN and ICM/TCN ratio compared with AzadC treatments (2/5/10 nM); however, control group TCN and ICM/TCN ratio was found lower. The methylation percentage of pDS4.1 and B. bubalis satellite DNA were comparatively more attenuated with 5 nM zebularine than 5 nM AzadC treatment. The increased in vitro development rates of the treated embryos were correlated with the decreased level of DNA methylation and the improved blastocyst quality. Following transfer of 5 nM zebularine treated embryos to 6 recipients, 4 were found to be pregnant, though the pregnancies were not carried to full term.  相似文献   
995.
Abstract

The half‐life of 2‐chloro‐6‐(trichloromethyl)‐pyridine in three soils varied from 43 to 77 days at 10 C and from 9 to 16 days at 20 C. The Q10 values were highest in coarse textured soils.  相似文献   
996.
997.
Strigolactones (SLs) are carotenoid-derived plant hormones involved in several growth and developmental processes. Also, SLs are allelochemicals that induce the seed germination of root parasitic plants and the hyphal branching of arbuscular mycorrhizal fungi. In this study, to identify novel lead chemicals that inhibit SL biosynthesis, we evaluated the effect of agrochemicals on SL biosynthesis. We found that the diacylhydrazine insect growth regulator, chromafenozide, reduced the endogenous level of 4-deoxyorobanchol (4DO), a major SL in rice. Furthermore, treatment with the same class of insect growth regulator, methoxyfenozide, also resulted in the reduction of 4DO levels in rice root exudates. These results suggest that chromafenozide and methoxyfenozide are novel lead inhibitors of SL biosynthesis.  相似文献   
998.
马铃薯抑芽剂 CIPC(isoprophyl chloro-carbanilate)在刚出休眠期及采后2个月的薯块上应用都有明显的抑芽效果。在常温下141d 发芽率为10%,抑芽效果与低温贮藏的相似。CIPC 与杀菌剂混合使用可以减轻腐烂,CIPC 与多菌灵混用的效果最好。  相似文献   
999.
A novel angiotensin‐converting enzyme (ACE) inhibitory peptide was isolated and purified from chicken bone extract by enzymatic digestion. The peptide was defined as an ACE inhibitor, and it demonstrated antihypertensive activity following oral administration to spontaneously hypertensive rats (SHRs). The results of this study suggest that peptides derived from an extract of chicken bones, administered orally, have the ability to reduce the blood pressure of SHRs significantly over a short period of time (3 h). Moreover, the blood pressure then remains low for 3 h. This peptide derived from chicken bones may therefore have great value as a short‐term remedy for chronic conditions such as high blood pressure. The amino acid sequence of the peptide was YYRA (Tyr‐Tyr‐Arg‐Ala), which was the origin of the Ig heavy chain V region (27–30 position). The IC50 value of its synthetic peptide was 33.9 μg/mL. We suggest that the ACE inhibitory and antihypertensive peptides derived from chicken bone extract may contribute to develop physiologically functional foods or improve food functionality.  相似文献   
1000.
A phase I clinical trial evaluating the toxicity of orally-administered imatinib mesylate was performed in 9 tumor-bearing cats. Imatinib is a small molecule, tyrosine kinase inhibitor, which selectively blocks the function of overexpressed proteins associated with various malignancies. Cats included in the study had diagnoses of fibrosarcoma, squamous cell carcinoma, and mast cell tumor, and each cat was staged using CBC and serum biochemistry; urinalysis, thoracic radiographs, and abdominal ultrasonography were performed in some cats. Most cats were treated previously by surgery, radiation therapy, chemotherapy, or some combination of these treatments. None of the cats received any concurrent chemotherapy. Six cats were treated with imatinib mesylate at 1-2 mg/kg PO q24h. Dose escalations were made to 2, 4, and 10 mg/kg PO q24h in 5 cats. Two cats started therapy at 10 mg/kg PO q24h, and 1 cat started therapy at 15 mg/kg PO q24h; all 3 cats remained at these dosages. No signs of toxicity, as evaluated by CBC and serum biochemistry, were noted in 8 of the 9 cats, and minimal gastrointestinal toxicity was observed. Due to the low frequency of adverse effects, further evaluation of imatinib is ongoing at a dosage of 10 mg/kg PO q24h.  相似文献   
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