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41.
This study aimed to evaluate the efficiency of immunocastration in lambs using testicular morphometry. Thirty lambs were randomly divided into two treatments (subcutaneous administration of 1.0 mL and 0.5 mL of an anti-GnRH vaccine) and a control group (1.0 mL saline solution). The animals were vaccinated at four months of age, received a second dose 30 days later, and were slaughtered 90 days after the first vaccine dose. After slaughter, testicles were collected, and samples were removed for histological processing and evaluation of testicular morphometric parameters. Analysis of variance, Tukey’s test, and Kruskal–Wallis test were performed, with a 5% level of significance. There was a reduction in testicular weight, gonadosomatic index, seminiferous tubule diameter, germinal epithelium height, leydigosomatic index, and total tubule length. The total length per testicular gram increased in the immunocastrated group. Intrinsic spermatogenesis yield, Sertoli cell indices, and estimates of sperm and Sertoli cell production were reduced in the immunized groups (P < 0.05). The anti-GnRH vaccine in lambs at doses of 1.0 mL and 0.5 mL is sufficient to promote immunocastration, verified through severe changes in testicular morphometry from animals.  相似文献   
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Microsatellite flanking regions are not necessarily unique sequences, but they may group into sequence families. Microsatellites occurring within such families are likely to give multiple banding patterns during polymerase chain reaction amplifications. microfamily (version 1) is a program that detects flanking‐region similarities between different microsatellite‐containing sequences, thus allowing for potentially problematic sequences to be eliminated prior to primer design. The program also accomplishes some otherwise tedious sequence editing, such as checking for nonpermitted characters, and eliminates poorly readable extremities or potential vector/adapter contamination. microfamily is written in Perl and available for Linux and Windows systems at http://www.up.univ‐mrs.fr/local/egee/dir/meglecz/microfamily.html .  相似文献   
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Microsatellite loci were developed from Parnassius apollo and Euphydryas aurinia, two endangered Palaearctic butterfly species. Respectively, six and five polymorphic loci were characterized from an enriched partial genomic library. Genetic diversity range from three to 25 alleles for the first species and from seven to 21 for the second. Although the presence of null alleles is suspected, these polymorphic loci are likely to provide important information on the fine scale genetic structure among populations of these species.  相似文献   
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Alterations of phospholipid (PL) profiles have been associated to disease and specific lipids may be involved in the onset and evolution of cancer; yet, analysis of PL profiles using mass spectrometry (MS) in breast cancer cells is a novel approach. Previously, we reported a lipidomic analysis of PLs from mouse mammary epithelial and breast cancer cells using off‐line thin layer chromatography (TLC)‐MS, where several changes in PL profile were found to be associated with the degree of malignancy of cells. In the present study, lipidomic analysis has been extended to human mammary epithelial cells and breast cancer cell lines (MCF10A, T47‐D, and MDA‐MB‐231), using TLC‐MS, validated by hydrophilic interaction liquid chromatography‐MS. Differences in phosphatidylethanolamine (PE) content relative to total amount of PLs was highest in non‐malignant cells while phosphatidic acid was present with highest relative abundance in metastatic cells. In addition, the following differences in PL molecular species associated to cancer phenotype, metastatic potential, and cell morphology were found: higher levels of alkylacyl PCs and phosphatidylinositol (PI; 22:5/18:0) were detected in migratory cells, epithelial cells had less unsaturated fatty acyl chains and shorter aliphatic tails in PE and sphingomyelin classes, while PI (18:0/18:1) was lowest in non‐malignant cells compared to cancer cells. To date, information about PL changes in cancer progression is scarce, therefore results presented in this work will be useful as a starting point to define possible PLs with prospective as biomarkers and disclose metabolic pathways with potential for cancer therapy. J. Cell. Physiol. 228: 457–468, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Apoptosis in amastigotes from hamsters infected with visceral leishmaniasis was absent 30-day post-infection but appeared 90-day post-infection in the liver and spleen, as analysed using the TUNEL method. Necrosis was not present in these tissues and the nuclei of macrophages harbouring apoptotic amastigotes were preserved. Amastigote DNA fragmentation was demonstrated using agarose gel electrophoresis. DNA fragmentation was evident 90-day post-infection, coinciding with the occurrence of apoptosis of amastigotes in the tissues. Apoptosis of Leishmania amastigotes in vivo may constitute a mechanism that regulates growth of the parasite population during infection.  相似文献   
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AIMS AND BACKGROUND: The enzyme cytochrome P450 plays an important role in the metabolization and detoxification of various compounds. CYP1A1 is a polymorphic enzyme and some of its alleles have been correlated with an increased risk of developing various types of cancer. The aim of this study was to investigate the incidence of the polymorphism A-->G (Ile462Val, exon 7) in colorectal cancer patients and the correlation of this polymorphism with others risk factors. PATIENTS AND METHODS: 114 Brazilian patients with colorectal cancer were matched by age and sex to 114 healthy individuals. DNA was extracted from peripheral blood and the genotypes of the polymorphisms were assessed by PCR-restriction fragment length polymorphism. RESULTS: In the case group 64 subjects were male, 53 were alcohol users and 68 were smokers. In the control group 61 were male, 67 were alcohol users and 53 smokers. There were 14 subjects with wild-type homozygous A/A, 97 with heterozygous A/G, and 3 with homozygous mutated G/G in the cancer group versus 81 subjects with wild-type homozygous A/A and 33 with heterozygous A/G in the control group. The presence of the G allele (OR 5.14, 95%CI 3.15-10.80) was associated with an increased risk of colorectal cancer (p=0.001). The prevalence of smokers was higher in the cancer group (p=0.047, OR 1.71, 95%CI 1.03-3.11). CONCLUSION: These results suggest a positive association between the A-->G polymorphism and the risk of colorectal cancer. In addition, smoking was also a colorectal cancer risk. We did not find any correlation between this polymorphism and sex, grade of differentiation, stage, or evolution of the disease.  相似文献   
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Neuroendocrine and exocrine cells secrete proteins in either a constitutive manner or via the regulated secretory pathway (RSP), but the specific sorting mechanisms involved are not fully understood. After gene transfer to rat salivary glands, the transgenic model proteins human growth hormone (hGH) and erythropoietin (hEpo) are secreted primarily into saliva (RSP; exocrine) and serum (constitutive; endocrine), respectively. We hypothesized that fusion of hGH at either the C-terminus or the N-terminus of hEpo would re-direct hEpo from the bloodstream into saliva. We constructed and expressed two fusion proteins, hEpo-hGH and hGH-hEpo, using serotype 5-adenoviral vectors, and delivered them to rat submandibular glands in vivo via retroductal cannulation. Both the hEpo-hGH and hGH-hEpo fusion proteins, but not hEpo alone, were secreted primarily into saliva (p < 0.0001 and p = 0.0083, respectively). These in vivo studies demonstrate for the first time that hGH, in an N- as well as C-terminal position, influences the secretion of a constitutive pathway protein.  相似文献   
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