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981.
In the ovary, the development of new capillaries from pre‐existing ones (angiogenesis) is a complex event regulated by numerous local factors. The dominant regulators of angiogenesis in ovarian follicles and corpora lutea are the vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), insulin‐like growth factor (IGF), angiopoietin (ANPT) and hypoxia‐inducible factor (HIF) family members. Antral follicles in our study were classified according to the oestradiol‐17‐beta (E2) content in follicular fluid (FF) and were divided into five classes (E2 < 0.5, 0.5–5, 5–20, 20–180 and >180 ng/ml FF). The corresponding sizes of follicles were 5–7, 8–10, 10–13, 12–14 and >14 mm, respectively. Follicle tissue was separated in theca interna (TI) and granulosa cells (GC). The corpora lutea (CL) in our study were assigned to the following stages: days 1–2, 3–4, 5–7, 8–12 13–16 and >18 of the oestrous cycle and months 1–2, 3–4, 6–7 and >8 of pregnancy. The dominant regulators were measured at mRNA and protein expression levels; mRNA was quantified by RT‐qPCR, hormone concentrations by RIA or EIA and their localization by immunohistochemistry. The highest expression for VEGF‐A, FGF‐2, IGF‐1 and IGF‐2, ANPT‐2/ANPT‐1 and HIF‐1‐alpha was found during final follicle maturation and in CL during the early luteal phase (days 1–4) followed by a lower plateau afterwards. The results suggest the importance of these factors for angiogenesis and maintenance of capillary structures for final follicle maturation, CL development and function.  相似文献   
982.
983.
984.
Used in both beef cattle and dairy cows, monensin can provide many health benefits but can, when unintended overexposures occur, result in adverse effects. Information on serum and tissue concentrations following overexposure and/or overt toxicosis which may aid in diagnostics and clinical outcome is lacking. The aim of this study was to determine concentrations of monensin in biological specimens following oral exposure for 10 days to an approved dose (1 mg/kg) and a higher dose (5 mg/kg) of monensin given daily on a body weight basis to 10 dairy cows. No deaths were reported; cows receiving 5 mg/kg showed early signs of toxicosis including depression, decreased feed intake, and diarrhea after 4 days of exposure. Histopathological findings were minimal in most cows. Pharmacokinetic modeling of the detected serum concentrations for the 1 and 5 mg/kg dose groups determined the Cmax, Tmax, and t1/2λ to be 0.87 and 1.68 ng/mL, 2.0 and 1.0 h, and 1.76 and 2.32 days, respectively. Mixed regression models showed that the dose level and days since last dose were significantly associated with monensin concentrations in all four tissues, and with cardiac troponin levels. The high dose resulted in a significant elevation of monensin in tissues at approximately 4.7 times compared to the monensin concentrations in the tissues of animals from the low‐dose group. The cTnI concentrations in the high‐dose group were 2.1 times that of cTnI in the low‐dose group. Thus, the ability to diagnose monensin overexposure and/or toxicosis will improve from knowledge of biological monensin concentrations from this study.  相似文献   
985.
Masitinib, a selective tyrosine kinase inhibitor, has previously been shown to enhance the antiproliferative effects of gemcitabine in human pancreatic cancer, demonstrating potential as a chemosensitizer. This exploratory study investigated the ability of masitinib to sensitize various canine cancer cell lines to doxorubicin, vinblastine, and gemcitabine. Masitinib strongly sensitized histiocytic sarcoma cells to vinblastine (>70-fold reduction in IC(50) at 5 μM masitinib), as well as osteosarcoma and mammary carcinoma cells to gemcitabine (>70-fold reduction at 5-10 μM). In addition, several cell lines were sensitized to doxorubicin (2-10-fold reduction at 10 μM). These data establish proof-of-concept that masitinib in combination with chemotherapeutic agents can generate synergistic growth inhibition in various canine cancers, possibly through chemosensitization. The findings justify further investigation into those combinations that may potentially yield therapeutic benefit.  相似文献   
986.
Many rangeland processes are driven by microclimate and associated ecohydrological dynamics. Most rangelands occur in drylands where evapotranspiration normally dominates the water budget. In these water-limited environments plants can influence abiotic and biotic processes by modifying microclimate factors such as soil temperature and potential soil evaporation. Previous studies have assessed spatial variation in microclimate and associated ecohydrological attributes within an ecosystem (e.g., under vs. between woody canopies) or across ecosystems (e.g., with differing amounts of woody canopy cover), but generally lacking are assessments accounting systematically for both, particularly for evergreen woody plants. Building on recently quantified trends in near-ground solar radiation associated with a piñon–juniper gradient spanning 5% to 65% woody canopy cover, we evaluated trends in soil temperature and associated estimates of potential soil evaporation as a function of amount of woody canopy cover for sites overall and for associated canopy vs. intercanopy locations. Quantified soil temperature trends decreased linearly with increasing woody canopy cover for intercanopy as well as canopy patches, indicating the coalescing influence of individual canopies on their neighboring areas. Notably, intercanopy locations within high-density (65%) woody canopy cover could be as much as ~10°C cooler than intercanopy locations within low-density (5%) cover. Corresponding potential soil evaporation rates in intercanopies within high-density woody canopy cover was less than half that for intercanopies within low density. Our results highlight ecohydrological consequences of density-dependent shading by evergreen woody plants on soil temperature and potential soil evaporation and enable managers to rapidly estimate and compare approximate site microclimates after assessing amounts of woody canopy cover. Such predictions of microclimate have general utility for improving management of rangelands because they are a fundamental driver of many key processes, whether related to understory forage and herbaceous species or to wildlife habitat quality for game or nongame species.  相似文献   
987.
988.

Background

Intensive care units (ICUs) in human hospitals are consistently noisy environments with sound levels sufficient to substantially decrease sleep quality. Sound levels in veterinary ICUs have not been studied previously, but environmental sound has been shown to alter activity in healthy dogs.

Hypothesis

Veterinary ICUs, like those in human medicine, will exceed international guidelines for hospital noise.

Animals

NA.

Methods

Prospective, observational study performed consecutively and simultaneously over 4 weeks in 2 veterinary ICUs. Conventional A‐weighted sound pressure levels (equivalent continuous level [a reflection of average sound], the sound level that is exceeded 90% of the recording period time [reflective of background noise], and maximum sound levels) were continuously recorded and the number of spikes in sound >80 dBA were manually counted.

Results

Noise levels were comparable to ICUs in human hospitals. The equivalent continuous sound level was higher in ICU1 than in ICU2 at every time point compared, with greatest differences observed on week day (ICU1, 60.1 ± 3.7 dBA; ICU2, 55.9 ± 2.5 dBA, P < .001) and weekend nights (ICU1, 59.9 ± 2.4 dBA; ICU2, 53.4 ± 1.7 dBA, P < .0001) reflecting a 50% difference in loudness. Similar patterns were observed for the maximum and background noise levels. The number of sound spikes was up to 4 times higher in ICU1 (162.3 ± 84.9 spikes) than in ICU2 (40.4 ± 12.2 spikes, P = .001).

Conclusions and Clinical Importance

These findings show that sound in veterinary ICUs is loud enough to potentially disrupt sleep in critically ill veterinary patients.  相似文献   
989.
以分离自西藏那曲县罗玛镇传统发酵酸牦牛奶中的乳酸乳球菌乳脂亚种(Lactococcus lactis subsp.Cremoris)IMAU60064为试验菌株,研究其最佳的培养条件。对碳源、氮源、缓冲盐等培养基成分及培养条件进行优化,并采用响应面法对优选的碳源、氮源和缓冲盐类的组成含量进行优化,得到IMAU60064的增殖培养基为:葡萄糖23g/L、大豆蛋白胨11g/L、牛肉膏11g/L、胰蛋白胨5g/L、NaAC1.8g/L、K2HP041.2g/L、柠檬酸钠1.2g/L、MgSO4·7H200.4g/L、MnSO4·5H2O54mg/L、L-半胱氨酸盐酸盐0.5g/L、吐温80为1g/L。Lactococcus lactis subsp.cremorisIMAU60064在此增殖培养基中经30℃,14h培养活菌数可达到3.26×10^8cFu/mL,比在MRS中(6.54×10^7CFU/mL)提高近5倍。  相似文献   
990.
Ten nesting leatherback sea turtles on Trinidad were anaesthetised for electroretinogram (ERG) measurements, using ketamine and medetomidine, reversed with atipamezole. They weighed 242 to 324 kg and were given initial doses of 3 to 8 mg/kg ketamine and 30 to 80 microg/kg medetomidine administered into an external jugular vein; six of the turtles received supplementary doses of 2.6 to 3.9 mg/kg ketamine combined with 0 to 39 microg/kg medetomidine. The lower doses were used initially to ensure against overdosage and reduce the chances of residual effects after the turtles returned to the water, but successful ergs called for step-wise dose increases to the required level of anaesthesia. Respiratory rate, heart rate, electrocardiogram, cloacal temperature, and venous blood gases were monitored, and blood was collected for plasma biochemistry. At the end of the erg procedure, atipamezole was administered at 150 to 420 microg/kg (five times the dose of medetomidine), half intramuscularly and half intravascularly. The turtles were monitored and prevented from re-entering the water until their behaviour was normal. No apparent mortalities or serious anaesthetic complications occurred. The observed within-season return nesting rate of the anaesthetised turtles was comparable with that of unanaesthetised turtles.  相似文献   
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