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排序方式: 共有307条查询结果,搜索用时 15 毫秒
71.
Immunohistochemical expression of Epidermal Growth Factor Receptor (EGFR) in canine mammary tissues 总被引:2,自引:0,他引:2
Epidermal Growth Factor Receptor (EGFR) has been extensively studied in human breast cancer; however, systematic studies of EGFR protein expression in canine mammary gland tumours are lacking. Therefore, we evaluated its immunohistochemical expression in a series of 136 canine mammary tumours and representative areas of adjacent normal and hyperplastic mammary tissue and investigated a possible correlation between EGFR overexpression and several clinicopathological parameters and survival. In normal and hyperplastic canine mammary glands, EGFR expression was consistently observed in myoepithelial cells, with luminal cells usually negative. In tumour tissues, EGFR overexpression was found in 9 benign (19.6%) and 38 malignant (42.2%) lesions, with EGFR positivity significantly related with malignancy. Besides animal age and tumour size, there were no significant associations between other clinicopathological parameters and EGFR overexpression. On survival analysis, tumours with EGFR overexpression showed a reduced disease-free and overall survival; however these associations failed to reach statistically significant levels. 相似文献
72.
E. Ferreira A. C. Bertagnolli M. F. Cavalcanti F. C. Schmitt G. D. Cassali 《Veterinary and comparative oncology》2009,7(4):230-235
Tumour size is considered one of the most important determinants of clinical staging in cancer patients. The aim of this study was to assess the value of tumour size as an indicator of the differentiation of mammary neoplasias in female dogs. The tumour, nodes metastates (TNM) system, based on primary lesion size, the extent of its dissemination to regional lymph nodes and the presence or absence of distant metastases, was applied to 120 female dogs diagnosed with mammary neoplasias. Paraffin blocks from 38 cases were selected and studied by immunohistochemical staining for prognostic and predictive markers of breast cancer. The Kaplan–Meier survival curve was estimated for 110 female dogs. Larger tumours (T3) were mostly malignant and showed lower expression of progesterone receptor and higher expression of cellular proliferation markers. Global survival time was shorter in female dogs with large tumour masses. This study highlights the importance of tumour size as a prognostic indicator of mammary neoplasias in female dogs. 相似文献
73.
Extended drought periods followed by heavy rainfall may increase in many regions of the Earth, but the consequences for the quality of soil organic matter and soil microbial communities are poorly understood. Here, we investigated the effect of repeated drying and re‐wetting on microbial communities and the quality of particulate and dissolved organic matter in a Haplic Podzol from a Norway spruce stand. After air‐drying, undisturbed soil columns were re‐wetted at different intensities (8, 20 and 50 mm per day) and time intervals, so that all treatments received the same amount of water per cycle (100 mm). After the third cycle, SOM pools of the treatments were compared with those of non‐dried control columns. Lignin phenols were not systematically affected in the O horizons by the treatments whereas fewer lignin phenols were found in the A horizon of the 20‐ and 50‐mm treatments. Microbial biomass and the ratio of fungi to bacteria were generally not altered, suggesting that most soil microorganisms were well adapted to drying and re‐wetting in this soil. However, gram‐positive bacteria and actinomycetes were reduced whereas gram‐negative bacteria and protozoa were stimulated by the treatments. The increase in the (cy 17: 0 + cy 19: 0)/(16:1ω7c + 18:1ω7c) ratio indicates physiological or nutritional stress for the bacterial communities in the O, A and B horizons with increasing re‐wetting intensity. Drying and re‐wetting reduced the amount of hydrolysable plant and microbial sugars in all soil horizons. However, CO2 and dissolved organic carbon fluxes could not explain these losses. We postulate that drying and re‐wetting triggered chemical alterations of hydrolysable sugar molecules in organic and mineral soil horizons. 相似文献
74.
The photostability of pirimicarb, (2-dimethylamino-5,6-dimethylpyrimidin-4-yl dimethylcarbamate) in aqueous media, under natural and artificial sunlight irradiation conditions, is reported. The pH of the irradiated solutions remained constant during degradation time. The photodegradation mechanism seemed to be similar under both conditions, but the half-life was found to be about three times longer under natural than under artificial conditions. Four main photo-products ( 1 , 2 , 3 and 4 ) were isolated and identified by spectroscopic methods. It is proposed that a common photodegradation pathway exists for pirimicarb under both irradiation conditions. The results obtained from the photodegradation of pirimicarb and of its four main products isolated on solid phase permit the construction of a possible photodegradation pathway. Photoproduct 4 (2-methyl-formylamino-5,6-dimethyl-4-hydroxypyrimidine) is here described for the first time. 相似文献
75.
Ovarian and endocrine responses associated with the treatment of cystic ovarian follicles in dairy cows with gonadotropin releasing hormone and prostaglandin F2alpha, with or without exogenous progesterone
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Ambrose DJ Schmitt EJ Lopes FL Mattos RC Thatcher WW 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(11):931-937
The objectives of this observational study were to document ovarian and endocrine responses associated with the treatment of cystic ovarian follicles (COFs) in dairy cows, using gonadotropin releasing hormone (GnRH) and prostaglandin F2alpha (PGF) with or without exogenous progesterone. A secondary objective was to determine pregnancy establishment following synchronization of ovulation and timed insemination in cows diagnosed with COFs. In trial I, 18 Holstein cows diagnosed with COFs received 2 injections of 100 microg GnRH, 9 d apart, with 25 mg PGF given 7 d after the 1st GnRH. A new follicle developed in all 18 cows after the 1st GnRH, and 83% of cows ovulated following the 2nd GnRH. Cows were inseminated 16 h after the 2nd GnRH. Of the 17 cows available for pregnancy diagnosis, 7 were confirmed pregnant. In trial II, 8 cows with COFs received GnRH and an intravaginal progesterone device (CIDR) concurrently, then PGF 7 d later. The CIDR was removed 2 d after PGF administration. Plasma estradiol concentrations declined following CIDR insertion. In all cows, a new follicle developed following GnRH treatment; estradiol-surge and estrus occurred spontaneously after CIDR-removal. Seven of 8 cows ovulated the new follicle. In dairy cows diagnosed with COFs, treatment with GnRH followed by PGF 7 d later, with or without exogenous progesterone, resulted in the recruitment of a healthy new follicle; synchronization of ovulation and timed insemination resulted in a 41% pregnancy rate. 相似文献
76.
Francisco J. Pallarés Cameron S. Schmitt James A. Roth Richard B. Evans Joann M. Kinyon Patrick G. Halbur 《Canadian journal of veterinary research》2004,68(3):236-240
The efficacy of currently available washed whole cell Streptococcus suis bacterins is generally poor. We developed and tested the efficacy of a novel ceftiofur-washed whole cell bacterin. Sixty-six, 2-week-old specific pathogen free (SPF) pigs were randomly divided into 5 groups. Three groups were vaccinated 28 and 14 d prior to challenge. The 3 ceftiofur-washed whole cell bacterins each contained 1 of 3 different adjuvants (Montanide ISA 25, Montanide ISA 50, and Saponin). Pigs exhibiting severe central nervous system disease or severe joint swelling and lameness were euthanized immediately and necropsied. All remaining pigs were necropsied at 14 d post inoculation. The ceftiofur-washed whole cell S. suis bacterin with Montanide ISA 50 adjuvant significantly (P < 0.05) reduced bacteremia, meningitis, pneumonia, and mortality associated with S. suis challenge. Further work on this novel approach to bacterin production is warranted. 相似文献
77.
78.
79.
O'Brien DJ Schmitt SM Hickling GJ 《Journal of the American Veterinary Medical Association》2002,221(10):1380-1; author reply 1381-2
80.
Konstantinidou-Doltsinis S. Markellou E. Kasselaki A. -M. Siranidou E. Kalamarakis A. Tzembelikou K. Schmitt A. Koumakis C. Malathrakis N. 《植物病害和植物保护杂志》2007,114(6):256-262
Journal of Plant Diseases and Protection - Six field trials were conducted in Greece to study the efficacy of two formulations of Reynoutria sachalinensis extract (Milsana® Vp 1999 &... 相似文献