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排序方式: 共有2356条查询结果,搜索用时 281 毫秒
91.
In this study, we report Monopis crocicapitella (Clemens, 1859) (Tineidae), which was collected from bat guano in a cave in the southern region of Korea, for the first time from East Asia. We briefly redescribe and illustrate the external morphology and genital structures of both sexes. Also, we discuss the local habitat characteristics and some of the ecological information that was observed during our field investi-gation.  相似文献   
92.
基于代码生成的电控空气悬架系统电子控制单元   总被引:1,自引:0,他引:1  
为提高某型SUV车辆的行驶平顺性、通过性等,对其进行空气悬架改装,并设计了由最小系统、车速信号调理模块、电动气泵控制模块、组合电磁阀控制模块、车身高度检测模块、CAN总线模块、车身加速度测量模块等组成的以Freescale XDP512为核心芯片的电控空气悬架系统电子控制单元,利用Real-Time Workshop(RTW)代码生成技术将所制定电控空气悬架系统控制策略转化为ANSI C代码并下载至电子控制单元,然后对安装电控空气悬架系统的试验车辆进行了车身高度与车速耦合试验、转向试验、急加速试验、急减速试验、平顺性试验,结果表明所设计的电控空气悬架系统控制单元能够实现车速信号调理、车身高度与车速耦合、电动气泵控制及组合阀控制等功能。  相似文献   
93.
A monoclonal antibody (MAb-001), against a surface glycoprotein on Cryptobia salmositica inhibited the multiplication and oxygen consumption of both virulent and avirulent strains of the parasite. The classical cysteine proteinase inhibitor (E-64) and a cysteine proteinase activator (EDTA) affected the in vitro multiplication of C. salmositica . Concentrations of E-64 higher than 10 μ M reduced the multiplication of C. salmositica while 5 m M of EDTA enhanced its multiplication. We propose that the cysteine proteinase is an important metabolic enzyme in C. salmositica and that binding of MAb-001 to the enzyme inhibited parasite multiplication and reduced oxygen consumption.  相似文献   
94.
Cholecystectomy is the current standard recommended treatment for dogs with gallbladder mucoceles. However, medical management with monitoring has also been recommended for asymptomatic dogs. The purpose of this retrospective study was to compare ultrasonographic patterns of gallbladder mucoceles with clinical disease status in a group of dogs. For each included dog, the ultrasonographic pattern of the mucocele was classified into one of six types: type 1, immobile echogenic bile; type 2, incomplete stellate pattern; type 3, typical stellate pattern; type 4, kiwi like pattern and stellate combination; type 5, kiwi like pattern with residual central echogenic bile; and type 6, kiwi like pattern. A total of 43 dogs were included. Twenty‐four dogs, including 11 dogs with gallbladder rupture, were symptomatic. Nineteen dogs were asymptomatic. Cholecystectomy (n = 19), medical therapy (n = 17), or monitoring (n = 6) treatments were applied according to clinical signs and owners’ requests. One dog suspected of having gallbladder rupture was euthanized. Frequencies of gallbladder mucocele patterns were as follows: type 1 = 10 (23%), type 2 = 13 (30%), type 3 = 5 (12%), type 4 = 11 (26%), type 5 = 4 (9%), and type 6 = 0. In dogs with gallbladder rupture, type 2 (8/13) was the most common. No significant correlations were found between ultrasonographic patterns of gallbladder mucoceles and clinical disease status or gallbladder rupture. Findings indicated that ultrasonographic patterns of gallbladder mucoceles may not be valid bases for treatment recommendations in dogs.  相似文献   
95.
Diagnosis of unilateral diaphragmatic paralysis in dogs is currently based on fluoroscopic detection of unequal movement between the crura. Bilateral paralysis may be more difficult to confirm with fluoroscopy because diaphragmatic movement is sometimes produced by compensatory abdominal muscle contractions. The purpose of this study was to develop a new method to evaluate diaphragmatic movement using M‐mode ultrasonography and to describe findings for normal and diaphragmatic paralyzed dogs. Fifty‐five clinically normal dogs and two dogs with diaphragmatic paralysis were recruited. Thoracic radiographs were acquired for all dogs and fluoroscopy studies were also acquired for clinically affected dogs. Two observers independently measured diaphragmatic direction of motion and amplitude of excursion using M‐mode ultrasonography for dogs meeting study inclusion criteria. Eight of the clinically normal dogs were excluded due to abnormal thoracic radiographic findings. For the remaining normal dogs, the lower limit values of diaphragmatic excursion were 2.85–2.98 mm during normal breathing. One dog with bilateral diaphragmatic paralysis showed paradoxical movement of both crura at the end of inspiration. One dog with unilateral diaphragmatic paralysis had diaphragmatic excursion values of 2.00 ± 0.42 mm on the left side and 4.05 ± 1.48 mm on the right side. The difference between left and right diaphragmatic excursion values was 55%. Findings indicated that M‐mode ultrasonography is a relatively simple and objective method for measuring diaphragmatic movement in dogs. Future studies are needed in a larger number of dogs with diaphragmatic paralysis to determine the diagnostic sensitivity of this promising new technique.  相似文献   
96.
Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging.  相似文献   
97.
In this study, we determined how rosiglitazone (RSG) differentially affected hippocampal neurogenesis in mice fed a low-fat diet (LFD) or high-fat diet (HFD; 60% fat). LFD and HFD were given to the mice for 8 weeks. Four weeks after initiating the LFD and HFD feeding, vehicle or RSG was administered orally once a day to both groups of mice. We measured cell proliferation and neuroblast differentiation in the subgranular zone of the dentate gyrus using Ki67 and doublecortin (DCX), respectively, as markers. In addition, we monitored the effects of RSG on the levels of DCX and brain-derived neurotrophic factor (BDNF) in hippocampal homogenates. At 8 weeks after the LFD feeding, the numbers of Ki67- and DCX-positive cells as well as hippocampal levels of DCX and BDNF were significantly decreased in the RSG-treated group compared to the vehicle-treated animals. In contrast, the numbers of Ki67- and DCX-positive cells along with hippocampal levels of DCX and BDNF in the HFD fed mice were significantly increased in the RSG-treated mice compared to the vehicle-treated group. Our data demonstrate that RSG can modulate the levels of BDNF, which could play a pivotal role in cell proliferation and neuroblast differentiation in the hippocampal dentate gyrus.  相似文献   
98.
Various somatic cell nuclear transfer (SCNT) techniques for mammalian species have been developed to adjust species-specific procedures to oocyte-associated differences among species. Species-specific SCNT protocols may result in different expression levels of developmentally important genes that may affect embryonic development and pregnancy. In the present study, porcine oocytes were treated with demecolcine that facilitated enucleation with protruding genetic material. Enucleation and donor cell injection were performed either simultaneously with a single pipette (simplified one-step SCNT; SONT) or separately with different pipettes (conventional two-step SCNT; CTNT) as the control procedure. After blastocysts from both groups were cultured in vitro, the expression levels of developmentally important genes (OCT4, NANOG, EOMES, CDX2, GLUT-1, PolyA, and HSP70) were analyzed by real-time quantitative polymerase chain reaction. Both the developmental rate according to blastocyst stage as well as the expression levels CDX2, EOMES, and HSP70 were elevated with SONT compared to CTNT. The genes with elevated expression are known to influence trophectoderm formation and heat stress-induced arrest. These results showed that our SONT technique improved the development of SCNT porcine embryos, and increased the expression of genes that are important for placental formation and stress-induced arrest.  相似文献   
99.
Woo PT 《Journal of fish diseases》2003,26(11-12):627-646
Salmonid cryptobiosis is caused by Cryptobia (Trypanoplasma) salmositica. The haemoflagellate has been reported from all species of Pacific Oncorhynchus spp. on the west coast of North America. It is normally transmitted by the freshwater leech, Piscicola salmositica, in streams and rivers, and sculpins, Cottus spp., are considered important reservoir hosts. The pathogen can also survive on the body surface of fish because it has a contractile vacuole to osmoregulate when the fish is in fresh water. This allows for direct transmission between fish, especially in aquaculture facilities. The parasite divides rapidly by binary fission in the blood to cause disease, the severity of which is directly related to parasitaemia. Cryptobia salmositica has a mitochondrium and it normally undergoes aerobic respiration; however, if its mitochondrium is damaged it will switch to glycolysis. Its glycolytic enzymes and catalase are contained in glycosomes. Cysteine protease is a metabolic enzyme, and its neutralization inhibits oxygen consumption and multiplication of the parasite. An important virulent factor in cryptobiosis is a secretory metalloprotease. The protective mechanism involves production of complement fixing antibodies, phagocytosis by macrophages, and cell-mediated cytotoxicity. Recovered fish are protected, probably for life as the immunity is non-sterile. Clinical signs of the disease include anaemia, anorexia, splenomegaly, general oedema and abdominal distension with ascites. The metabolism and swimming performance of infected fish are significantly reduced and the bioenergetic cost of the disease is very considerable. Fish are susceptible to hypoxia and their immune system is depressed during acute cryptobiosis. Severity of the disease and mortality rates vary significantly between species and stocks of salmon. Protective strategies include selective breeding of Cryptobia-resistant fish. This is innate resistance to infection and it is controlled by a dominant Mendelian locus. In these fish the parasite is lysed via the alternative pathway of complement activation. In Cryptobia-tolerant fish (infected with the pathogen but which do not suffer from disease) the metalloprotease secreted by the parasite is neutralized by alpha2 macroglobulin. Hence, the production of a transgenic Cryptobia-tolerant salmon is an option. This strategy has the advantage in that human intervention (e.g. vaccination, chemotherapy) is not required once the transgenic fish is produced. Acquired immunity is another option; a single dose of the attenuated live vaccine protects fish for at least 2 years. The protective mechanism in vaccinated fish is similar to that in recovered fish. The trypanocidal drug, isometamidium chloride, is an effective therapeutic and prophylactic agent. It accumulates in the mitochondrium of the parasite and significantly disrupts aerobic respiration by causing lesions in the organelle. Efficacy of the drug is significantly increased after its conjugation to antibodies. This immuno-chemotherapeutic strategy has the advantage in that it will lower the drug dosage and hence side-effects of chemotherapy. It will probably reduce the accumulation of the drug in fish, an important consideration in food fish.  相似文献   
100.
Following the increasing public health concerns related to physical inactivity in the population, the relationship between outdoor recreation and public health has been increasingly acknowledged over the last decades. To improve public health, planners and policy-makers aim to provide good accessibility to recreational landscapes to facilitate outdoor recreational activity. At the same time, they are facing development pressure due to urban growth. In order for planners and policy-makers to secure people access to urban and near urban recreational areas, there is a need to map and measure access in a way that is adequate as a basis for decision-making in planning and design processes. Access is often defined as distance, or proximity, from residents’ homes to recreational areas. This paper explores different ways to map and measure distance to recreational areas, and aims to provide better decision support for planners and decision-makers. Moss municipality in Norway serves as a case study. We begin by addressing the meaning of the term ‘recreational landscape’ and how the choice of definition affects the results when mapping recreational areas. We also discuss who we are measuring distance for, and how different user groups will have different thresholds or critical distances affecting their frequency of visits to a recreational area. Last, we explore different methods for measuring distance within a GIS environment. The paper shows how the purpose of the analysis must be decisive when defining recreational landscapes and choosing methods for measuring access to recreational landscape, in order to provide valuable input to planners and policy-makers aiming at enhancing the possibility for outdoor recreation for people.  相似文献   
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