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121.
昆虫色斑型与基因型的关联性以及与环境适应性的关系,是昆虫学的研究热点之一。异色瓢虫Harmonia axyridis Pallas作为一种重要的昆虫色斑多型性资源,受到广泛重视。本文于2012-2015年通过调查统计泰安市异色瓢虫不同时期鞘翅底色、不同位置斑点、联斑、二窗型和四窗型、性比等指标的变化特点,并进行了多项式拟合、χ2(卡方)检验和相关性分析,明确了异色瓢虫色斑型和性比的周年变化特点及其与月平均气温的关系。结果表明,浅色型异色瓢虫中,浅色型、不同位置斑点和联斑数量比例均随月份先降后升,与月平均温度显著负相关,均在夏季出现最低值。深色型中,深色型数量比例随月份先升后降,与月平均温度显著正相关;其中的二窗型数量比例在夏季和冬季上升,春季和秋季下降,四窗型则相反,但均于月平均气温相关性不显著,相关系数分别为-0.09和0.09。异色瓢虫种群、浅色型和深色型均表现为偏雌现象,在夏季更为明显,且与月平均气温显著正相关,相关系数分别为0.79、0.90和0.66。χ2检验可知,异色瓢虫浅色型和深色型数量、不同位置斑点数量、联斑数量、二窗型和四窗型数量以及种群、浅色型和深色型雌雄数量均与月份显著关联。综合分析可知,异色瓢虫浅色型中各指标受月平均气温影响均较大。除数量比例和性比受温度影响较大外,深色型中二窗型和四窗型比例变化较小。异色瓢虫各指标均月份显著关联。  相似文献   
122.
河流生态径流计算的逐月频率计算法   总被引:15,自引:1,他引:15  
李捷  夏自强  马广慧  郭利丹 《生态学报》2007,27(7):2916-2921
界定了生态径流、最小生态径流、最大生态径流、适宜生态径流的概念,提出了一种新的河流生态径流计算方法——逐月频率计算法,指出了方法的优缺点以及适用范围。以计算洛阳市境内伊河的栾川站和龙门镇站生态径流为例,说明了计算过程,同时用Tennant法作对比。结果表明:运用新的逐月频率计算法比用以往的逐月频率计算法得到的适宜生态径流过程径流量要大,河流的生态状况更好,更有利于河流自身的生态健康和河流周围生物栖息地的保护。  相似文献   
123.
国家Ⅰ级重点保护极危植物藤枣研究进展   总被引:1,自引:0,他引:1  
国家Ⅰ级重点保护植物藤枣[Eleutharrhena macrocarpa(Diels)Forman]属防己科单种属植物,主要分布于云南南部地区。藤枣因其形态特征和分布式样在防己科植物中较为独特,具有重要的植物系统学和区系地理学研究价值。据相关文献记载,目前发现和记录的藤枣自然种群数量小于60株,种群处于极危状态,面临灭绝风险。国内外与藤枣相关的研究资料也相对匮乏。为及时拯救和关注这一濒危物种,该文在前贤研究的基础上,总结报道了藤枣的分类学简史、科学研究价值、自然种群数量、濒危状况、生物多样性保护地位、区系分布、模式标本认定等方面的最新研究进展,提出了近期的研究目标。期望能对藤枣的准确鉴定、精准调查和进一步深入研究提供基础信息和理论参考。  相似文献   
124.
125.
The covalent bonding of riboflavin to succinic dehydrogenase is accomplished via the 8-α (methyl group) carbon and probably the 3 nitrogen of histidine. The absence of a carbon of this configuration in 7-methyl-8-ethyl-10-(1′-d-ribityl)isoalloxazine suggests that such bonding could not take place with this flavin; however, studies of the enzyme in rat tissues containing only this flavin homolog provides evidence that the bonding does take place. Administration of this homolog to weanling rats as their only source of flavin permits a normal rate of growth and development. During the first 40 days the succinic acid hydrogenase activities for the kidney, heart, and liver fall precipitously to 70, 60, and 55%, respectively, of normal and they are then maintained at these levels. These animals, as well as comparable animals receiving the isomeric 7-ethyl-8-methyl-10-(1′-d-ribityl)isoalloxazine, thrive while receiving a daily supplement of the homologs but they show an immediate flavin-deficiency response as a loss of weight when the flavins are withheld. The administration of 7,8-diethyl-10-(1′-d-ribityl)isoalloxazine, a potent competitive antagonist of riboflavin, to adult rats causes changes in the succinic dehydrogenase activities of the kidney, heart, and liver which mimic those observed when the animal is deprived of riboflavin.  相似文献   
126.
目的:对一例全身大面积机械性损伤致死及由之所致的多系统器官衰竭死亡病例的相关问题进行讨论分析。方法:回顾性分析该病例的临床资料并对其行详细认真的尸体检验与死因鉴定。结果:本案尸检、临床所见及相关实验室检查已证实伤者因钝性暴力作用于全身软组织致使大面积软组织挫伤,多发性肋骨骨折并因多系统器官功能衰竭死亡。讨论:在整个病程中多器官系统的功能衰竭并非各自独立分别发生,而是互相影响,互相作用甚至互为因果恶性循环的结果,这在本例的临床病历资料中已充分体现。因此,在进行机械性损伤致死的法医学鉴定中,应注意区分多系统器官功能衰竭和挤压综合症的鉴别问题。  相似文献   
127.
We present here the estimation of the upper limit of the number of molecular targets in the human genome that represent an opportunity for further therapeutic treatment. We select around ∼6300 human proteins that are similar to sequences of known protein targets collected from DrugBank database. Our bioinformatics study estimates the size of ‘druggable’ human genome to be around 20% of human proteome, i.e. the number of the possible protein targets for small-molecule drug design in medicinal chemistry. We do not take into account any toxicity prediction, the three-dimensional characteristics of the active site in the predicted ‘druggable’ protein families, or detailed chemical analysis of known inhibitors/drugs. Instead we rely on remote homology detection method Meta-BASIC, which is based on sequence and structural similarity. The prepared dataset of all predicted protein targets from human genome presents the unique opportunity for developing and benchmarking various in silico chemo/bio-informatics methods in the context of the virtual high throughput screening.  相似文献   
128.
A case of breast sparganosis was confirmed by surgical excision of a worm (fragmented into 5 pieces) in a 59-year-old Korean woman suffering from a palpable mass in the left breast. Mammography and ultrasonography characteristically revealed the presence of several well-defined, isodense and hypoechoic tubular masses, in the upper quadrant of the left breast, each mass consisting of a continuous cord- or worm-like structure. During surgery, a long segment of an actively moving sparganum of Spirometra sp. and 4 small fragments of the same worm, giving a total length of 20.3 cm, were extracted from the upper outer quadrant of the left breast and the axillary region. The infection source remains unclear, because the patient denied ingesting any snake or frog meat or drinking untreated water.  相似文献   
129.
Peripheral gangrene, characterized by distal ischemia of the extremities, is a rare complication in patients with falciparum malaria. Patients with this complication have generally undergone early amputation of the affected areas. In this report, we describe 3 adult Thai patients presented at the Hospital for Tropical Diseases, Bangkok, with high grade of fever ranged 6-9 days, jaundice, acute renal failure, respiratory failure, alteration of consciousness and shock. Two patients had gangrene developed at the lower extremities on day 1 of hospitalization and 1 patient had gangrene developed on day 3. Blood smears revealed hyperparasitemia with Plasmodium falciparum. These patients were diagnosed as having severe malaria with peripheral gangrene. The resolution of gangrene was successfully achieved by treatment with artesunate and conservative treatment in 2 of 3 cases.  相似文献   
130.
Three cases of cutaneous larva migrans (CLM) were diagnosed in a returnee from a trip to Thailand and in 2 domestic farmers during July and September, 2003. The linear and serpiginous skin lesions on the lower extremities were presented in all 3 cases. Routine laboratory findings were normal. In the imported case, a 650 x 30 micrometer sized filariform nematode larva, presumably a species of hookworm, was detected in the lesion. All cases were treated with 400 mg albendazole once daily for 3-5 days, and their skin lesions gradually improved. In the present study, a causative agent of CLM was isolated for the first time in the Republic of Korea. Moreover, we speculate that CLM is prevalent in farmers who are in frequent contact with soil in the Republic of Korea.  相似文献   
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