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11.
Dendritic cells (DCs) are a heterogeneous population of cells of fundamental importance in initiating innate as well as specific immune responses. The identity and function of DCs in the cat are unknown, although they are likely pivotal in the response to infection. In this study, feline DCs were derived by 3-10-day culture of adherent blood mononuclear cells (PBMCs) and bone marrow mononuclear cells (BMMCs) in the presence of IL 4 and GM-CSF. BMMC consistently yielded a greater number of DCs than PBMC, and there were fewer macrophages than DC from both compartments. DCs expressed a distinct constellation of surface molecules, which included CD1a, CD1b, and CD1c, CD11b, CD14, and 2-3-fold higher levels of MHC class I and II molecules than co-cultured macrophages or fresh blood monocytes. DCs displayed typical cytoplasmic processes, limited non-specific esterase activity, and acquired antigen by phagocytosis, pinocytosis, and binding to specific receptors. Cytokine-exposed cells induced proliferation of allogeneic lymphocytes. Thus, the cells derived by these culture conditions had markers and functions analogous to immature myeloid DCs. Availability of feline DCs will enable investigation of their role in infectious disease and their potential therapeutic application.  相似文献   
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对松狮这个品种情有独钟的人一定知道美国最顶尖的松狮犬舍之——Imagine犬舍,美国国家认可的松狮俱乐部等级中首屈一指的犬舍。他们的松狮犬以帝王的外形、健全的身体和头脑而著称。Imagine犬舍坐落在美国南加州的圣贝纳迪诺山脚下,松树、桉树、棕榈树与盛开的丝兰和仙人掌围绕着他们美丽的家园,不远处就是积雪覆盖的山脉,绿、蓝、白的交会,组成了—幅美丽的画面。而对于犬舍主理人Kathy Beliew女士和她的丈夫George,更是广大松狮迷眼中偶像级的人物。  相似文献   
13.
An immersion technique for studying wood wettability   总被引:1,自引:1,他引:1  
Summary The wetting properties of wood were studied by a modification of the Wilhelmy technique. This method involved continuously monitoring the force exerted on a wood specimen as it was immersed at a controlled rate into a liquid. Wettability was expressed in terms of the area under the force-immersion curve and was referred to in this study as wettability index. The applicability of the technique was demonstrated for padauk and white spruce wood specimens heated for various time periods. The wettability of these woods in both distilled water and sodium hydroxide solutions decreased with increasing heating time. Sodium hydroxide solution yielded higher wettability index values, indicating that it was a better wetting agent than distilled water. The pH of the sodium hydroxide solution had a strong influence on magnitude of the wettability index. The possibility of using the technique for examining wood surface inactivation in relation to bonding with different adhesives is discussed.The authors gratefully acknowledge the assistance of Dr. W. G. Warren and his staff for the statistical analyses and curve fitting. Dr. Casilla also expresses his gratitude to the National Research Council of Canada and to the Canadian Forestry Service, Department of the Environment, for a postdoctoral fellowship  相似文献   
14.
Mangroves worldwide provide a wide range of ecosystem services utilized directly and indirectly by local peoples. Between 1966 and 2001, Bangladesh established approximately 148,000 ha of mangrove plantations in coastal areas within the Barisal and Chittagong Divisions. Though erosion and human encroachment and conversion have removed over two-thirds of these stands, the Forest Department has continued to undertake new plantation activities.

To investigate how and to what degree people directly utilize these mangroves, I conducted 340 household surveys across eight coastal villages located in close proximity to established plantations. The predominant direct use of the mangrove plantations by local rural communities is the extraction of detritus and nonmain stem material (e.g., limbs, leaves) for combustible fuel. This study uses household foraging distances to estimate and map net value densities based on reported market prices of extracted goods. The average extractive value of mangrove plantations is Tk 2,300 ha?1 yr?1, ranging among the villages from 300 to Tk 27,400 ha?1 yr?1, with values concentrated closer to the village. Cost-benefit analyses suggest that direct use values alone have justified the establishment and management of previously planted stands. However, other indirect values must be taken into account if these areas are to merit additional plantations.  相似文献   
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Early postoperative neuroimaging has been performed in people for over 20 years to detect residual brain tumor tissue and surgical complications. The purpose of this retrospective study was to describe characteristics observed using early postoperative magnetic resonance imaging in a group of dogs undergoing craniotomy for brain tumor removal. Two independent observers came to a consensus opinion for presence/absence of the following MRI characteristics: residual tumor tissue; hemorrhage and ischemic lesions; abnormal enhancement (including the margins of the resection cavity, choroid plexus, meninges) and signal intensity changes on diffusion‐weighted imaging. Five dogs were included in the study, having had preoperative and early postoperative MRI acquired within four days after surgery. The most commonly observed characteristics were abnormal meningeal enhancement, linear enhancement at margins of the resection cavity, hemorrhage, and a thin rim of hyperintensity surrounding the resection cavity on diffusion‐weighted imaging. Residual tumor tissue was detected in one case of an enhancing tumor and in one case of a tumor containing areas of hemorrhage preoperatively. Residual tumor tissue was suspected but could not be confirmed when tumors were nonenhancing. Findings supported the use of early postoperative MRI as a method for detecting residual brain tumor tissue in dogs.  相似文献   
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A 4‐year‐old German shorthaired pointer presented with collapse and hematochezia. Radiographs showed gas and fluid‐distended small intestines and loss of serosal detail. Ultrasound examination showed hypomotile, fluid‐distended small intestines, and thrombosed jejunal veins. Multiphasic contrast‐enhanced computed tomography was performed and showed a CT “whirl sign,” an important but nonspecific sign of intestinal volvulus in human patients. At surgery, the majority of the small intestine was entangled in the volvulus and showed black discoloration. The patient was euthanized. Postmortem evaluation yielded a diagnosis of jejunoileal mesenteric volvulus secondary to a congenital omphalomesenteric duct remnant.  相似文献   
20.
In this study, new marine ningalin B analogues containing a piperazine or a benzoloxy group at ring C have been synthesized and evaluated on their P-gp modulating activity in human breast cancer and leukemia cell lines. Their structure-activity relationship was preliminarily studied. Compounds 19 and 20 are potent P-gp inhibitors. These two synthetic analogues of permethyl ningalin B may be potentially used as effective modulators of P-gp-mediated drug resistance in cancer cells.  相似文献   
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