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111.
Population size and distribution of Otaria flavescens in central and southern Chubut, Patagonia were determined by aerial censuses conducted during the breeding season in 1989 and 1995 and outside the season. Pup numbers were corrected by means of a linear regression between pup and adult male (AM) numbers obtained from terrestrial censuses carried out in 1994 and 1996. During the 1989 breeding season, 10,557 sea lions occurred at 29 locations; 2,800 (26.3%) were pups. During the 1995 breeding season, 14,887 animals were censused at 32 sites; 3,311 (22.2%) were pups. The corrected pup number increased to 4,852, indicating that around 32% is lost when counting from photographs. The corrected total number increased to 16,483; this fell to less than one half between breeding seasons (November 1990 and 1995). The 1995 breeding season census represents the highest number since 1972 (8,800) and the widest historical dispersion (37 sites year round contrasting with 13 in the late 1940s and 1972). However, the present number is about one half of the 33,000 censused about 50 yr ago. Using a correction factor developed for the north Paragonian population (1.8 × censused number) the present population size in the area can be estimated at around 29,669 individuals. 相似文献
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113.
四川宜宾七种中药提取物体外抗菌活性研究 总被引:1,自引:0,他引:1
用肉汤二倍稀释法和琼脂平板培养计数法,研究四川宜宾七种中药的提取物对大肠杆菌、沙门氏菌和巴氏杆菌的体外抑制作用.结果表明:黄柏提取物的抗菌活性最强,最小抑菌浓度(Minimum inhibitory concentration,MIC)为15.6~125 mg·mL-1,最小杀菌浓度(Minimum bactericidal concentration,MBC)为31.25~250 mg·mL-1;栀子提取物抗菌活性次之,MIC 为62.5~125 mg·mL-1,MBC 为125~>250 mg·mL-1;佛手提取物有较稳定的抗菌活性,MIC均为125 mg·mL-1,MBC为125 mg·mL-1和250 mg·mL-1;姜黄、杜仲、何首乌、细毡毛忍冬的提取物抗菌活性相对较差,大部分 MIC≥250 mg·mL-1.说明四川宜宾的黄柏和栀子的提取物抗菌活性较强,佛手提取物抗菌活性较稳定,有进一步研究的价值. 相似文献
114.
Redrawing the map: mtDNA provides new insight into the distribution and diversity of short‐finned pilot whales in the Pacific Ocean 下载免费PDF全文
Amy M. Van Cise Phillip A. Morin Robin W. Baird Aimee R. Lang Kelly M. Robertson Susan J. Chivers Robert L. Brownell Jr. Karen K. Martien 《Marine Mammal Science》2016,32(4):1177-1199
Correlations between morphological and genetic data provide evidence to delineate species or evolutionarily significant units, which then become the units to conserve in management plans. Here, we examine the distribution and genetic differentiation of two morphotypes of short‐finned pilot whale (Globicephala macrorhynchus) in the Pacific Ocean. Mitochondrial control region sequences from 333 samples were combined with 152 previously published sequences to describe genetic variability globally and population structure in the Pacific. Although genetic variability is low, we found strong differentiation at both broad and local levels across the Pacific. Based on genetics, two types are distributed throughout the Pacific, one predominantly in the eastern Pacific and the other in the western and central Pacific. In the eastern Pacific Ocean, no correlation was found between distribution and sea surface temperature. The two types have broad latitudinal ranges, suggesting their distributions are likely driven by more complex factors, such as prey distribution, rather than sea surface temperature. 相似文献
115.
In vivo phage display is a high-throughput method for identifying target ligands specific for different vascular beds. Targeting is possible due to the heterogeneous expression of receptors and other antigens in a particular vascular bed. Such expression is additionally influenced by the physiological or pathological status of the vasculature. In vivo phage display represents a technique that is usable in both, vascular mapping and targeted drug development. In this review, several important methodological aspects of in vivo phage display experiments are discussed. These include choosing an appropriate phage library, an appropriate animal model and the route of phage library administration. In addition, peptides or antibodies identified by in vivo phage display homing to specific types of vascular beds, including the altered vasculature present in several types of diseases are summarized. Still, confirmation in independent experiments and reproduction of identified sequences are needed for enhancing the clinical applicability of in vivo phage display research. 相似文献
116.
Hepatoprotective effect of Herpetospermum caudigerum Wall. on carbon tetrachloride‐induced hepatic fibrosis in rats 下载免费PDF全文
Xin Feng Ge‐jia Zhong Da Ji Deng Ba Bin Yang Lvyi Chen Shouying Du 《Journal of cellular and molecular medicine》2018,22(7):3691-3697
Tibetan medicine Herpetospermum caudigerum Wall. (HCW) has long been employed to treat hepatitis, inflammatory diseases and jaundice according to the records of “The Four Medical Tantras” in China. This study was investigated to explore the protective effects of HCW on hepatic fibrosis and the possible mechanism in a rat model. Hepatic fibrosis was established by intragastric administration of 3 ml/kg carbon tetrachloride (CCl4) twice a week for 6 weeks. CCl4‐treated rats were received HCW (1 and 3 g/kg/d) and silymarin (0.1 g/kg/d) from 3 to 6 weeks. The results showed that HCW could significantly decrease the levels of AST, ALT, HA, LN, PCIII, Col IV, TNF‐α, IL‐1β and IL‐6. Moreover, HCW could effectively inhibit collagen deposition and reduce the pathological damage. Analysis experiments finally exhibited that HCW was able to markedly inhibit hepatic fibrosis by modulating the expressions of NF‐κB p65, IκBα, Samd3 and TGF‐β1 proteins. Therefore, our results suggest that HCW has hepatoprotective activity against CCl4‐induced hepatic fibrosis in rats by regulating the inflammatory responses. 相似文献
117.
胃溃疡是临床常见但十分棘手的消化系统疾病,主要临床表现为长期性、周期性、节律性上腹部疼痛。现代治疗多采用西医治疗,效果显著,但复发率高、不良反应较大。大量研究表明,祖国医学对治疗胃溃疡具有独特的优势,且在临床上取得了良好的疗效,尤其是大大降低了胃溃疡的复发率。关于中医药治疗胃溃疡的方式非常成熟且规范全面,主要包括辨证论治、专方加减、专药治疗、其他中医治法等,说明中医药治疗胃溃疡具有一定的特色及广阔的前景,同时也面临一些问题,需要医务人员共同思考并解决。现将中医药治疗胃溃疡的现状概述如下。 相似文献
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119.
Perspectives of diverse constituencies need to be incorporated when developing conservation strategies. In Menri (Medicine Mountains) of the Eastern Himalayas, Tibetan doctors and professional botanists were interviewed about conservation
of useful plants. We compare these two perspectives and find they differ significantly in conservation priorities (Wilcoxon
Signed Ranks P < 0.05), both in how they prioritized, as well as the priorities themselves. Tibetan doctors first consider which plants
are most important to their medical practice and, then secondarily, the conservation status of these plants. Additionally,
perceptions of threatened medicinal plants differ among Tibetan doctors who received medical training in Lhasa, who were local
trained, and who were self-taught. In contrast, professional botanists came to a consensus among themselves by first considering
the conservation status of plants and then considering use. We conclude that, in order to effect community based conservation,
opinions from both Tibetan doctors and professional botanists should be considered in establishing conservation priorities
and sustainable conservation programs. Furthermore, we set our own research agenda based on combined perspectives. 相似文献
120.
Phytoplankton of the Southern Ocean, 140–148°E and 40–53°S, was sampled from early austral summer Nov. 1995 to Dec. 1995 to
examine cell abundance, cell volume and biomass (cell carbon) distribution across the fronts. A total of 90 phytoplankton
taxa were identified. They were 50 diatoms, 37 dinoflagellates, 2 silicoflagellates, and 1 prymnesiophyte. 73 species were
observed from north of the subtropical convergence zone and 71 species from south of the subtropical convergence zone.Pseudonitzschia spp. was the most widely distributed species. Nanoplankton predominated cell number of phytoplankton throughout the stations.
The abundance of diatoms was higher than that of dinofiagellates. Total biomass profiles were dependent to microphytoplankton
biomass. Maximum cell number and biomass were observed from subsurface layer. Phytoplankton community changed across the subtropical
convergence zone and 50–53°S (antarctic convergence zone), and physicoehemical factors seem to controll the distribution. 相似文献