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51.
The oriental armyworm, Mythimna separata(Lepidoptera:Noctuidae) is a harmful pest which causes heavy loss in agricultural crops. Sex identification of M. separata is very important for understanding the biology and management of this pest. Development of fast and convenient methods to identify M. separata female and male is the necessary prerequisite for conducting gender-related studies. In this study, new methods to differentiate sex of M. separata at pupal and adult stages were investigated. Our results showed that posterior abdominal segments containing genital organs which are morphological traits to differentiate female and male. Genital openings are important characters for the female and male pupae differentiation. For female pupa, it locates on the ventral side of eighth and ninth abdominal segments and appears as a visible longitudinal suture; for male pupa, it locates on the ventral side of the ninth abdominal segment and appears as a short slit surrounded by a pair of visible semicircular lumps. Bristle numbers are another indicator for sex differentiation of adults. Each female has three-bristled frenulum and each male has one bristled-frenulum near the base of hind wing of each side of moth body. We confirmed the two sex differentiation methods manually by dissecting genitalia of adults and found their genger was as same as what we examined the sex of pupae and adults using the morphological methods.  相似文献   
52.
To assess the effects of a single supraphysiological postnatal administration of a progestogen on uterine glands in dogs, 10 females were randomly assigned to a medroxyprogesterone acetate 35 mg (MPA; n = 6) or placebo (n = 4) group within the first 24 h of birth. The safety of the treatment was also evaluated. A transient mild clitoris enlargement appeared in MPA-treated females. Microscopic postpubertal uterine assessment revealed the presence of uterine glands in all cases without significant differences in the area occupied by the glands per µm2 of endometrium nor in the height of the uterine epithelium.  相似文献   
53.
为揭示猪精子运动抑制因子(Seminal plasma motility inhibitor,SPMI)基因在公母猪生殖道的时空表达特性,本研究运用定性RT-PCR分析了SPMI在生殖道的组织表达谱,利用半定量RT-PCR技术分析了SPMI在公猪精囊腺和尿道球腺组织的发育性表达.定性RT-PCR分析结果发现,SPMI基因在精囊腺中的表达丰度最高,在尿道球腺和子宫角中呈中等丰度表达,在前列腺、子宫颈和卵巢中的表达较弱,在其它生殖道组织未检测到mRNA表达.半定量RT-PCR分析结果显示,SPMI基因在公猪精囊腺和尿道球腺中的发育性表达规律相似,都在初生时即启动,表达水平随着日龄的增加不断提高,直至性成熟(150日龄).其中SPMI基因在精囊腺中的表达在60、90和150日龄均有显著提高(P<0.05);而在尿道球腺中,SPMI基因的表达在30、90和150日龄均有显著提高(P<0.05),而60日龄的表达较30日龄时有所提高,但差异不显著(P>0.05).这些结果提示SPMI基因在公母猪生殖道呈广泛表达,其发育性表达呈日龄依赖性特点,表达水平在初情期至性成熟期有显著提高.  相似文献   
54.
16头 5月龄长白×大约克夏二元杂交母猪 ,通过不同途径接种猪繁殖与呼吸综合征病毒 (PRRSV)弱毒疫苗 ,采用组织学方法研究其对母猪生殖道黏膜淋巴细胞分布的影响。结果表明 ,与对照组相比 ,鼻腔和肌注接种可使猪子宫角、子宫体和子宫颈黏膜上皮内淋巴细胞的数量极显著增加 (P <0 0 1 ) ,生殖道接种则使淋巴细胞的数量极显著减少(P <0 0 1 )。鼻腔与肌注接种间无明显差异。经生殖道接种疫苗时 ,子宫黏膜上皮变得不规则 ,有些部位上皮变薄。而经鼻腔和肌注接种时 ,黏膜固有层中多见淋巴细胞聚集 ,形成淋巴细胞群 ,并向黏膜腔表面排放。提示不同途径接种PRRSV疫苗对母猪子宫黏膜及上皮内淋巴细胞的分布和组织结构具有显著的影响  相似文献   
55.
The aim of the present study was to describe the temperature of the different portions of the female genital tract and their relation to rectal temperature and to investigate the effect of steroid hormones profiles on these variables over the estrous cycle in cattle. Four nonpregnant Japanese Black cows were investigated daily over two successive estrous cycles using a digital thermometer with a long probe and rounded-end sensor to record the temperature of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT) and uterine horns (UHT). Blood samples were collected immediately before temperature recording to assay peripheral levels of progesterone (P4) and estradiol-17β (E2). Moreover, transrectal ultrasonography was carried out after temperature recording to monitor the ovulatory follicle and track ovulation. During the experiment, the ambient temperature and relative humidity were recorded for further calculation of the temperature humidity index (THI). The temperature within the genital tracts in these cows progressively increased towards the uterine horns from the vagina. The VT, CT, UBT and UHTs were significantly higher in association with peripheral P4 concentrations greater than 4 ng/ml (mid-luteal phase) when compared with lower peripheral P4 concentrations. The VT was more significantly (P<0.01) correlated to the CT, UBT and UHTs than RT. In conclusion, a temperature gradient was present among the vagina, cervix and uterus over the estrous cycle, and changes in peripheral P4 concentrations were associated with the thermal variations within these portions. The VT could be more beneficial than RT in monitoring temperature of deeper portions of the female genital tract in bovine.  相似文献   
56.
The female genital tract originates from the Müllerian ducts during embryological development. Fusion of the ducts occurs in different segments depending on the animal species, resulting in a variational number of the respective organ. Current literature on genital tract morphology of laboratory rodents is controversial. Therefore, the present study aimed at determining an anatomically correct definition of the uterus in laboratory guinea pigs, mice and rats. In all three rodent species, we found two separate cervical canals that communicate with an individual uterus via discrete ostia uteri interna. The correct anatomical definition should therefore be uterus duplex bicollis, vagina simplex.  相似文献   
57.
The aim of this study was to describe a modified surgical technique for treatment of severe penile pathology, and the long‐term outcome. The surgery consisted of subischial urethrostomy and penile amputation with preputial ablation, with the horse in dorsal recumbency. A redundant section of the penis root and body was left in situ, rather than being retroflexed as described elsewhere. Follow‐up was obtained using a structured owner telephone questionnaire. The 15 cases included: 11 squamous cell carcinomas (73.3%); 2 melanomas; one chronic preputial discharge with no associated neoplasia; and one paraphimosis following routine sedation. Length of survival ranged from 0.9 to 74.6 months (median 25.1 months). From the 14 horses with follow‐up, 9 survived >18 months (64.3%) [Correction added on 17 August 2015, after first online publication: The percentage in the preceding sentence was wrong and has been corrected to '64.3%' from '69.2%']. Four euthanasias were due to presenting or post operative complications, while 2 were unrelated to the procedure. This procedure presents a simplified, viable option for treatment of extensive mixed penile lesions; reducing surgical complexity and time in comparison to previously described techniques requiring retroversion.  相似文献   
58.
59.
Vaginal formulations for the prevention of sexually transmitted infections are currently gaining importance in drug development. Polysaccharides, such as chitosan and carrageenan, which have good binding capacity with mucosal tissues, are now included in vaginal delivery systems. Marine polymer-based vaginal mucoadhesive solid formulations have been developed for the controlled release of acyclovir, which may prevent the sexual transmission of the herpes simplex virus. Drug release studies were carried out in two media: simulated vaginal fluid and simulated vaginal fluid/simulated seminal fluid mixture. The bioadhesive capacity and permanence time of the bioadhesion, the prepared compacts, and compacted granules were determined ex vivo using bovine vaginal mucosa as substrate. Swelling processes were quantified to confirm the release data. Biocompatibility was evaluated through in vitro cellular toxicity assays, and the results showed that acyclovir and the rest of the materials had no cytotoxicity at the maximum concentration tested. The mixture of hydroxyl-propyl-methyl-cellulose with chitosan- or kappa-carrageenan-originated mucoadhesive systems that presented a complete and sustained release of acyclovir for a period of 8–9 days in both media. Swelling data revealed the formation of optimal mixed chitosan/hydroxyl-propyl-methyl-cellulose gels which could be appropriated for the prevention of sexual transmission of HSV.  相似文献   
60.
分析了洪涝胁迫下灾区农业结构调整与可持续发展的关系,并以湖北 鱼县为例,提出了洪涝胁迫与可持续发展导向双重制约下的农业结构调整的具体对策。  相似文献   
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