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161.
An epidemiological study of Babesia canis in dogs in Nigeria was performed. Four hundred blood samples collected from dogs in Nigeria were investigated using nested PCR and sequence analysis. On nested PCR screening, nine samples (2.3%) produced a band corresponding to a 698-bp fragment indicative of B. canis infection. Sequence analysis of the PCR products identified eight samples (2.0%) as B. canis rossi and the ninth (0.3%) as B. canis vogeli. This is the first report of the prevalence of B. canis rossi and B. canis vogeli in dogs in Nigeria.  相似文献   
162.
The biological effects of epicuticular substances in farinose exudates accumulated on inflorescence shafts and calyces of Primula denticulata on human acute myeloid leukemia cells (HL-60) were analyzed. The crude material possessed little antioxidative capacity but strong cytostatic properties. Some of its known components (5-hydroxyflavone, 2'-hydroxyflavone, 5,2'-dihydroxyflavone, and 5,8-dihydroxyflavone) were further tested to identify the biologically active compounds. The effects of these flavones on cell cycle progression, mitochondrial membrane potential, and reactive oxygen species have been investigated by flow cytometry. The flavonol quercetin was included in the study as reference compound because of its known cytostatic properties and its activity as radical scavenger. Compared to quercetin the flavones induced little apoptosis (up to 40 microM), but despite their low toxicity, the Primula flavonoids possessed strong cytostatic properties even at low concentrations. The cell cycle distribution showed a characteristic time-dependent shift, giving evidence of a generally short-lived effect of the test compounds in the exposed cells. The antioxidative properties quantified according to two different methods correlated with the number of hydroxyl groups. Whereas quercetin strongly affected the mitochondrial membrane potential, none of the Primula flavones showed a comparable effect.  相似文献   
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164.
闸站枢纽进水前池三维流动计算与研究   总被引:1,自引:0,他引:1  
采用雷诺平均纳维-斯托克斯方程(RNAS)和标准k-ε湍流模型,运用SIMPLEC算法,对某水利枢纽进行三维湍流数值模拟计算,预测了水流流动过程中产生的回流、旋涡发生的位置及形态;通过具体方案比较,提出了前池设置底坎的整流措施,有效地消除了回流与旋涡,流态显著改善,可为工程设计提供指导。  相似文献   
165.
A standard karyotype for the River Buffalo has recently been established. The largest five chromosomes are biarmed and, based on the banding homology between cattle and buffalo chromosomes, were suggested to originate from the fusion of cattle acrocentric chromosomes. The origin of buffalo chromosome 1 is controversial due to the difficulty in differentiating between the small acrocentric cattle chromosomes. Using molecular markers assigned to cattle chromosomes, synteny between CD18, a marker for BTA1, and markers for small acrocentric cattle chromosomes BTA 24 to BTA 29 was investigated in buffalo/hamster somatic cell hybrids. The investigation revealed that CD18 is syntenic with ANT1, a marker for cattle chromosome 27. The present results confirm that buffalo BBU1 results from fusion of cattle BTA 1 and BTA 27. They also underline the importance of biarmed buffalo chromosomes for the identification of small cattle acrocentrics.  相似文献   
166.
In this study, LH release in response to the GnRH agonist buserelin and during treatment with a progesterone-releasing intravaginal device (PRID) was studied. A dose of 20 micrograms buserelin induced a more pronounced LH release than 4, 8, 40 and 80 micrograms. After injection of buserelin, pituitary response to a second buserelin injection was markedly reduced for at least 24 hours. Repeated buserelin injections at an interval of several hours therefore cannot be recommended. LH release was markedly suppressed by treatment with PRID. Two PRID tended to be more effective than one. After PRID removal, LH release increased significantly.  相似文献   
167.
OBJECTIVE: To determine the outcome of horses with "complex" digital tenosynovitis treated by tenoscopic proximal annular ligament desmotomy and resection of synovial masses or adhesions, or both, within the digital sheath. STUDY DESIGN: Retrospective evaluation. ANIMALS OR SAMPLE POPULATION: Twenty-five horses with a clinical and ultrasonographic diagnosis of palmar or plantar proximal annular ligament constriction and ultrasonographic evidence of synovial masses or adhesions within the digital tendon sheath. METHODS: Each horse had tenoscopic surgery for annular ligament desmotomy combined with adhesiolysis and/or synovial mass resection. Mean follow-up time was 3.4 years. Spearman's rank correlation was used to assess the relationship between functional outcome or cosmetic results and preoperative variables including duration of clinical signs, digital sheath synovial fluid total protein concentration and nucleated cell count, thickness of the palmar or plantar proximal annular ligament (PAL), severity of adhesions, severity of synovial masses, degree of synovial distention, or limb affected. RESULTS: A total of 18 (72%) horses returned to athletic soundness, 4 were improved but not sound, and 3 were not improved. Cosmetic outcome was normal in 10 horses, improved but not normal in 12, and not improved in 3 horses. Cosmetic and functional outcome were significantly adversely affected by the duration of clinical signs and the severity of synovial masses. CONCLUSIONS: With appropriate tenoscopic surgical attention, horses with complex tenosynovitis syndrome characterized by synovial masses, adhesions, or both adhesions and masses, and PAL constriction, have a good prognosis for return to athletic soundness. CLINICAL RELEVANCE: Horses with PAL constriction and additional digital tendon sheath pathology such as adhesions and synovial masses have a 72% chance of returning to sound athletic performance, however 60% of horses retain some degree of cosmetic blemish in the affected limb. There is an inverse relationship between the duration of clinical signs and outcome, and therefore, prompt surgical attention is advised.  相似文献   
168.
Early pregnancy diagnosis could be associated with decreased diagnostic accuracy or increased fetal loss, which might lead to increased culling. We determined the relationship between pregnancy diagnosis at various intervals after artificial insemination and subsequent calving for cows from five dairy herds in California. Palpations were done by either of two experienced veterinarians. Cows diagnosed pregnant at a first pregnancy examination 41 days or less after insemination were significantly less likely to subsequently have a calf than were cows diagnosed later.  相似文献   
169.
170.
夏威夷澳洲坚果树速衰的新问题   总被引:1,自引:0,他引:1  
夏威夷的澳洲坚果(Macadamia integrifolia Maiden and Bet-che)出现了前所未有的新问题:叶片开始轻度褪绿,继而迅速变褐,最后整株树死亡。当有棘胫小蠹[Xyleborus afinis Eichhoff及X.perforans Wol-lastan(Coleoptera:Scolytidae)]侵害和真菌子实体形成后,树势即出现衰退现象。“Ikaika”是最易被侵害的品种。被棘胫小蠹侵害8.3±2.6(SD)个月后植株死亡。  相似文献   
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