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21.
The appropriate supply of nutrients in pregnant cows has been associated with the optimal development of foetal tissues, performance of their progeny and their meat quality. The aim of this study was to evaluate supplementation effects of grazing cows in different stages of gestation on skeletal muscle development and performance of the progeny. Thereby, 27 Nellore cows were divided into three groups (n=9 for each group) and their progeny as follows: UNS, unsupplemented during gestation; MID, supplemented from 30 to 180 days of gestation; LATE, supplemented from 181 to 281 days of gestation. The percentage composition of the supplement provided for the matrices was the following: ground corn (26.25%), wheat bran (26.25%) and soya bean meal (47.5%). The supplement was formulated to contain 30% CP. Supplemented matrices received 150 kg of supplement (1 and 1.5 kg/day for cows in the MID and LATE groups, respectively). After birth, a biopsy was performed to obtain samples of skeletal muscle tissue from calves to determine number and size of muscle fibres and for messenger RNA (mRNA) expression analysis. The percentage composition of the supplement provided for the progeny was the following: ground corn grain (30%), wheat bran (30%), soya bean meal (35%) and molasses (5%). The supplement was formulated to contain 25% CP and offered in an amount of 6 g/kg BW. Performance of the progeny was monitored throughout the suckling period. Means were submitted to ANOVA and regression, and UNS, MID and LATE periods of supplementation were compared. Differences were considered at P<0.10. Birth weight, average daily gain and weaning weight of the offspring did not differ among treatments (P>0.10). Similarly, no differences were observed between calves for nutrient intake (P>0.10). However, greater subcutaneous fat thickness (P=0.006) was observed in the calves of LATE group. The ribeye area (P=0.077) was greater in calves born from supplemented compared with UNS cows. The supplementation of pregnant cows did not affect the muscle fibre size of their progeny (P=0.208). On the other hand, calves born from dams supplemented at mid-gestation had greater muscle fibre number (P=0.093) compared with calves from UNS group. Greater mRNA expression of peroxysome proliferator-activated receptor α (P=0.073) and fibroblast growth factor 2 (P=0.003) was observed in the calves born from MID cows. Although strategic supplementation did not affect the BW of offspring, it did cause changes in carcass traits, number of myofibres, and mRNA expression of a muscle hypertrophy and lipid oxidation markers in skeletal muscle of the offspring.  相似文献   
22.
目的:分析盆底肌功能训练联合阴茎夹对前列腺增生术后患者尿失禁的临床应用效果。方法:选取我院2017年4月~2019年4月收治的72例前列腺增生术后尿失禁患者,随机分为对照组和观察组各36例,两组均予盆底肌功能训练,观察组加用阴茎夹控制排尿。对比两组术后尿失禁改善情况、排尿改善情况、国际尿失禁咨询委员会尿失禁问卷表简表(ICI-Q-SF)评分变化、压力性尿失禁分度评价及经济费用情况。结果:两组干预后20 d、干预后30 d、干预后90 d尿失禁发生率均较干预后10 d下降,观察组干预后10 d、干预后20 d、干预后30 d、干预后90 d尿失禁发生率均低于对照组,差异均有统计学意义(P0.05)。两组干预后90 d每日总尿量较干预前升高,每日总排尿次数、每日总漏尿次数均较干预前下降;观察组干预后90 d每日总尿量高于对照组,每日总排尿次数、每日总漏尿次数均低于对照组,差异均有统计学意义(P0.05)。两组干预后90d ICI-Q-SF评分均较干预前下降,且观察组干预后90d ICI-Q-SF评分低于对照组,差异均有统计学意义(P0.05)。观察组患者干预后压力性尿失禁临床治愈率高于对照组,差异有统计学意义(P0.05)。两组患者压力性尿失禁分度情况比较差异无统计学意义(P0.05)。观察组阴茎夹使用费用为(70.26±8.51)元,低于对照组的(388.71±26.44)元,差异有统计学意义(P0.05)。结论:在盆底肌功能训练的基础上联合阴茎夹能够有效改善前列腺增生术后患者尿失禁症状及生活质量,且有助于降低患者经济负担,值得临床推广应用。  相似文献   
23.
This protocol outlines the steps required to produce a robust model of infectious disease and colitis, as well as the methods used to characterize Citrobacter rodentium infection in mice. C. rodentium is a gram negative, murine specific bacterial pathogen that is closely related to the clinically important human pathogens enteropathogenic E. coli and enterohemorrhagic E. coli. Upon infection with C. rodentium, immunocompetent mice suffer from modest and transient weight loss and diarrhea. Histologically, intestinal crypt elongation, immune cell infiltration, and goblet cell depletion are observed. Clearance of infection is achieved after 3 to 4 weeks. Measurement of intestinal epithelial barrier integrity, bacterial load, and histological damage at different time points after infection, allow the characterization of mouse strains susceptible to infection.The virulence mechanisms by which bacterial pathogens colonize the intestinal tract of their hosts, as well as specific host responses that defend against such infections are poorly understood. Therefore the C. rodentium model of enteric bacterial infection serves as a valuable tool to aid in our understanding of these processes. Enteric bacteria have also been linked to Inflammatory Bowel Diseases (IBDs). It has been hypothesized that the maladaptive chronic inflammatory responses seen in IBD patients develop in genetically susceptible individuals following abnormal exposure of the intestinal mucosal immune system to enteric bacteria. Therefore, the study of models of infectious colitis offers significant potential for defining potentially pathogenic host responses to enteric bacteria. C. rodentium induced colitis is one such rare model that allows for the analysis of host responses to enteric bacteria, furthering our understanding of potential mechanisms of IBD pathogenesis; essential in the development of novel preventative and therapeutic treatments.  相似文献   
24.
α1-Adrenoceptor (α1-AR) antagonists are considered to be the most effective monotherapy agents for lower urinary tract symptoms associated with benign prostatic hyperplasia (LUTS/BPH). In this study, we synthesized compounds 217, which are novel piperazine derivatives that contain methyl phenylacetate. We then evaluated the vasodilatory activities of these compounds. Among them, we found that compounds 2, 7, 12, which contain 2-OCH3, 2-CH3 or 2, 5-CH3, respectively, exhibited potent α1-blocking activity similar to protype drug naftopidil (1). The antagonistic effects of 2, 7, and 12 on the (?)-noradrenaline-induced contractile response of isolated rat prostatic vas deferens (α1A), spleen (α1B) and thoracic aorta (α1D) were further characterized to assess the sub receptor selectivity. Compared with naftopidil (1) and terazosin, compound 12 showed the most desirable α1D/1A subtype selectivity, especially improved α1A subtype selectivity, and the ratios pA2 (α1D)/pA2 (α1B) and pA2 (α1A)/pA2 (α1B) were 17.0- and 19.5-fold, respectively, indicating less cardiovascular side effects when used to treat LUTS/BPH. Finally, we investigated the chiral pharmacology of 12. We found, however, that the activity of enantiomers (R)-12 and (S)-12 are not significantly different from that of rac-12.  相似文献   
25.
目的:探讨经尿道前列腺电切术(TURP)联合经尿道膀胱颈切开术(TUIBN)治疗小体积前列腺增生(BPH)所致膀胱出口梗阻的疗效。方法:选择2009年1月~2013年12月我院收治的小体积BPH患者,其中单纯经尿道前列腺电切术(TURP组)48例,经尿道前列腺电切术联合经尿道膀胱颈切开术(TURP+TUIBN组)48例。比较两组的术前、术后国际前列腺症状评分(IPSS)、残余尿量(PVR)、最大尿流率(Qmax)等,以及术后并发症的发生情况。结果:TURP+TUIBN组术中出血量较TURP组明显增多(P0.05),两组手术时间、组织切除质量比较,差异均无统计学意义(P0.05);与TURP组比较,TURP+TUIBN组术后6个月IPSS评分、PVR明显下降,Qmax、膀胱压力明显上升(P0.05);TURP+TUIBN组并发症发生率为4.2%,显著低于TURP组16.7%(P0.05)。结论:TURP+TUIBN治疗小体积前BPH所致膀胱出口梗阻,可彻底切除增生腺体,消除小体积BPH的各种梗阻因素,减少术后膀胱颈挛缩的发生。  相似文献   
26.
Chronic griseofulvin (GF) feeding induces preneoplastic foci followed by hepatocellular carcinoma in the mouse liver. Our previous study suggested that GF-induced hepatocellular proliferation had a different mechanism from that of peroxisome proliferator (PP)–induced direct hyperplasia. The GF-induced hepatocellular proliferation was mediated through activation of immediate early genes such as Fos, Jun, Myc, and NFκB. In contrast, PP-induced direct hyperplasia does not involve activation of any of these immediate early genes. It has been shown that nuclear hormone receptors including peroxisome proliferator activated receptors (PPARs) and retinoid x receptors (RXRs) play important roles in mediating the pleiotropic effects of PPs. To examine the possible roles of PPARs and RXRs during non-PP-induced hepatocellular proliferation and the interaction between PP and non-PP-induced proliferation, we have studied the expression of the PPAR and RXR genes in the GF model using northern blot hybridizations and gel retardation assays. The data showed that the expression of PPARα and RXRα genes was down-regulated in the livers containing preneoplastic nodules and in the liver tumors induced by GF. The mRNA down-regulation was accompanied by a decrease in the amount of nuclear protein–bound to peroxisome proliferator and retinoic acid responsive elements. Down-regulation was also associated with the suppressed expression of the PPARα/RXRα target genes (i.e., acyl-Co oxidase and cytochrome P450 4A1) and the catalase gene. The RXRγ gene was also down-regulated, but the RARα, β, and γ and PPARβ and γ genes were up-regulated. These results indicated that the hepatocarcinogenesis induced by GF is accompanied by suppression of the PPARα/RXRα-mediated direct hyperplasia pathway. The differential expression of these nuclear hormone receptors reveals a new aspect for understanding the individual roles and intercommunication of PPAR, RXR, and RAR isoforms in the liver. J. Cell. Biochem. 69:189–200, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
27.
Intimal hyperplasia is an important cause of stenosis or occlusion after vascular injury. Circular RNAs (circRNAs) are known to be related to various cardiovascular diseases. However, the expression profile of circRNAs in the neointima has not been reported in detail. In this study, we established a rat common carotid artery (CCA) injury model. A microarray detection showed significant differences in circRNA expression between the normal and injured CCA. Real-time quantitative polymerase chain reaction verified the differences. We used bioinformatics to predict the microRNAs that possibly interact with the differentially expressed (DE) circRNAs and linked the potential functions of circRNAs to the target genes of the microRNAs. We believe that the DE circRNA in neointima may affect the differentiation, proliferation, and migration of vascular cells through a variety of target genes. The intervention or utilization of certain circRNAs should be a new method for preventing and treating intimal hyperplasia.  相似文献   
28.
研究了热作用下的良性前列腺增生(BPH)组织对532 nm的KTP和1064 nm的Nd:YAG激光的吸收和散射特性的变化及其差异,实验采用双积分球测量系统以及反向倍增法获取BPH组织的吸收和散射特性。结果表明:热作用下的BPH组织对532 nm和1064 nm的吸收系数和约化散射系数都是随着加热温度的变化而变化的,在20℃到80℃的温度范围内,BPH组织对532 nm的吸收系数和约化散射系数都分别显著地较其对1064 nm的吸收系数和约化散射系数要大,其对532 nm和1064 nm的吸收系数的最大值都在20℃,其值分别为1.663 mm-1和0.127 mm-1,最小值分别在50℃和70℃,其值分别为0.864 mm-1和0.034 mm-1,其对532 nm和1064 nm的吸收系数的最大差异在70℃,其值为2647%,其对532 nm和1064 nm的约化散射系数的最大值都在80℃,其值分别为2.036 mm-1和1.421 mm-1,最小值分别在50℃和70℃,其值分别为1.499 mm-1和0.246 mm-1,其对532 nm和1064 nm的约化散射系数的最大差异在70℃,其值为555%,在70℃的热作用下BPH组织达到完全热凝固,其对532 nm和1064 nm的吸收和散射特性的差异达到最大值。  相似文献   
29.
Squamous cell carcinoma (SCC) of the oral cavity is one of the most common neoplasms in the world. During the past 2 decades, the role of high-risk human papilloma virus (HR-HPV) has been studied and the data supporting HPV as a one of the causative agents in the development and progression of a sub-set of head and neck squamous cell carcinomas (HNSCC) has accumulated. In order to investigate the role of HR-HPV oncogene expression in early epithelial alterations in vivo, we produced transgenic mice expressing HPV16 early region genes from the promoter of the bovine keratin 6 gene (Tg[bK6-E6/E7]). In this article, we demonstrate that E6/E7 transgene was abundantly expressed and cellular proliferation was increased in the middle tongue epithelia of transgenic mice, and that in the same region young (27 weeks old) Tg[bK6-E6/E7] mice spontaneously developed histological alterations, mainly focal epithelial hyperplasia (FEH).  相似文献   
30.
Estrogen-alpha receptor (ER) and progesterone receptor (PR) were examined immunohistochemically in uteri of normal bitches, in uteri of bitches with cystic endometrial hyperplasia-mucometra (CEH-M) and in uteri of bitches with endometritis-pyometra (E-P), under exogenous progesterone treatment.In the CEH-M group, the ER- and PR-scores of all uterine cell types were higher than the ER- and PR-scores of normal uteri, although these differences were not always statistically significant. The ER-scores of E-P group were significantly lower than the ER-scores of the normal uteri and CEH-M group. The PR-scores of the E-P group tended to be higher than the PR-scores of the normal uteri, except for the surface epithelium, although these differences were not statistically significant. Exogenous progesterone treated bitches with CEH-M or E-P showed reduced ER- and PR-scores in the different uterine cell types, compared with the corresponding nontreated CEH-M or E-P group.The differences in ER and PR expression between CEH-M and E-P suggest different factors in the pathogenesis of both entities. Although, these changes in ER and PR expression do not seem to be directly involved in the pathogenesis of CEH-M and E-P. It is suggested that for CEH-M and progestin induced CEH-M a hormone dependent pathway is responsible. For P, the trigger may be bacterial infection.  相似文献   
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