PROP1与联合垂体激素缺乏症

垂体特异性转录因子祖先蛋白(PROP l),是成对同源转录因子,在垂体腺中呈特异性表达,参与早期胚胎垂体的发育,因此,PROP1基因对于垂体前叶的发育是必需的。PROP1启动胚胎期垂体特异性转录因子(PIT-1)的起始表达并维持个体出生后的持续表达,且可直接促使PIT-1细胞系的前体分化为促性腺细胞系。其基因突变可使人、鼠患有联合垂体激素缺乏症(CPHD),表现为生长激素(GH)、促乳素(PRL)、促甲状腺素(TSH)以及促黄体激素(LH)、促卵泡激素(FSH)或促肾上腺皮质激素(ACTH)缺乏,垂体核磁共振成像显示垂体萎缩。在其它哺乳动物中PROP1突变也会引起垂体和性腺激素异常。就PROP1基因的结构与功能,以及与CPHD间的关系作一综述。     

富含绿原酸的植物中类黄酮测定方法探讨

以枇杷花、枇杷叶和金银花为材料,研究绿原酸干扰类黄酮测定的结果表明,差示分析法基本上不受绿原酸的干扰,可用于富含绿原酸植物中类黄酮的测定;而NaNO_2-Al(NO_3)_3比色法和二甘醇比色法均受绿原酸的严重干扰,测得的类黄酮含量明显偏高,NaNO_2-Al(NO_3)_3比色法测得的结果甚至超过总酚含量。     

三峡库区人类活动强度与景观格局的耦合响应

人类活动和景观格局是人地系统中两大要素的重要表征,探析人类活动强度与景观格局的耦合变化特征对揭示区域人地关系的演变意义重大。为弥补当前对人类活动强度与景观格局耦合响应研究的不足,构建了山区人类活动强度与景观格局耦合演变模型,提出了综合显性—隐性人类活动强度指数,定量评价了三峡库区腹地奉节县2000—2020年的人类活动强度,并通过双变量空间自相关模型探讨了综合人类活动强度与景观格局的空间耦合特征。研究表明：(1)奉节县的综合人类活动强度在时间上由2000年的11.59%增加为2020年的12.48%,在空间上表现为整体收缩,局部增强的特点,另外人类活动强度和景观格局的空间分布与奉节县的地形梯度密切相关;(2)奉节县的人类活动强度与景观格局空间耦合变化表现出协调型、拮抗型、逐渐协调型和逐渐拮抗型四种类型;(3)影响奉节县综合人类活动强度与景观格局的耦合变化的重要因子为距聚落距离、距县行政中心距离、高程等,社会经济因素逐渐成为区域社会生态系统演变主导因素;(4)三峡库区腹地人类活动强度与景观格局存在耦合响应,且其耦合响应具有一定的多样性和特殊性。三峡库区腹地通过沟谷土地集约化来换取山区的生...     

中国农业系统近40年温室气体排放核算

基于排放因子法构建了包含种植业和牲畜养殖业的农业系统温室气体排放核算体系,系统核算了1980-2020年我国全国尺度上的农业系统温室气体排放总量和变化趋势,并在区县级尺度下对1980、2000、2011年的中国农业系统的温室气体排放量进行核算,对比不同阶段农业系统温室气体排放变化的时空异质性规律。研究发现：1980-2020年我国农业系统温室气体排放量呈波动增长趋势,增长了近46%。CH₄是农业系统排放贡献最大的温室气体,占总排放量的47.33%。我国农业系统温室气体排放与不同地区农业生产方式有关,CH₄排放量高的地区主要位于我国主要水稻产区以及旱地作物产区。CO₂排放量高的地区主要位于东北、西北等地区以及华东地区。N₂O排放量较高地区主要位于西北的主要畜牧养殖地区,以及我国农业经济发展水平高的中南部地区。研究有助于揭示我国农业温室气体排放的动态特征,现状规律,以及空间差异性特征,从农业减排角度为实现双碳目标提供科学参考。     

桂西北典型喀斯特区生态服务价值的环境响应及其空间尺度特征

Study on ecosystem service values (ESVs) is the bridge of understanding ecosystem and economic decision-making. To investigate the response of ESVs to ambient environment and their spatial scales is an urgent work in the process of ecological restoration and sustainable development in southwest China. Based on the previous research results, the remote images, and weather data of 31 years (1975-2005), the response of ESVs to ambient environment and their spatial scales in a typical karst area of northwest Guangxi, China were evaluated with the method of empirical mode decomposition (EMD) in this paper. The results showed that ESVs had obvious variations with changes in elevation, rocky types and soil types, and had corresponding characteristics of spatial scales. The ESVs in middle and low elevation areas were higher, but they decreased due to human activities such as deforestation. The ESVs in peak-cluster depression areas were lower, and they would increase as influenced by policies such as returning farmland to forestland. The ESVs were influenced by rocky types, showing lower values but an increasing trend in the typical karst regions while higher values but a decreasing trend in non-karst regions. The average ESVs in the west part of the study region, which is not only the main nature reserve for rare wildlife species in Guangxi, but also one of the best preserved natural vegetation regions in China, were more than 15,000 RMB Yuan ha-1,. Comparatively, the ESVs were less than 10,000 Yuan ha-1 in the middle part of the region attributed to low vegetation coverage, serious peak-cluster depression and karst rocky desertification. After about 20 years, that is from 1985 to 2005, the ecosystem conditions had been improved and the ESVs had increased in the middle and eastern part of this study region. On the contrary, in most western part, which was dominated by subtropical evergreen broad-leaved forest, they had been worsened, and the balance values of ESVs were negative. As for the relationships of ESVs with rocky types and soil types, lime soil and red soil were the two main soil types that contributed to ESVs (The total contribution was above 60%, and it is 63.77%,64.37%,64.56%,64.91% respectively in the four years of 1985, 1990, 2000 and 2005.). The variance contribution of intrinsic mode function (IMF) and trend (R) showed that there were obvious special sales for ESVs in this study area, and the main spatial scales were about 2.7 km, 5.5 km, and 11.6 km. The variance contribution ratio was 12.29%, 11.26%, 11.49% respectively, and the trend (R) was high (17.74%). In conclusion, this study indicated that ecosystem conditions in the typical karst area were improved owing to the application of rocky desertification control policies, such as ecological migration and returning farmland to forestland. Besides, the main spatial scales of ESVs in the study area were the interactions of terrain, physiognomy, land use / land cover and human activities.     

甘肃马鬃山北山羊春季卧息地的选择

2010年4～5月,在甘肃马鬃山采用样线法对北山羊Capra ibex春季卧息地的选择性进行了研究,共测定了63个卧息地样方,63个对照样方.经过分析表明,北山羊卧息地选择偏好利用阳坡、上坡位、膜果麻黄与裸岩(P<0.05),同时具有海拔高、坡度大、远离道路、远离居民点、距水源较近、接近隐蔽物、隐蔽级高等特征(P<0....     

柿ξ-胡萝卜素脱氢酶基因的克隆与序列分析

通过对柿ζ-胡萝卜素脱氢酶(-ζCarotene desaturase,ZDS)基因的克隆及序列分析,旨在为改良柿果实品质奠定基础。根据GenBank中其他植物ZDS基因的保守序列设计了两条PCR扩增引物,以柿果实中所提取的RNA为模板,采用RACE技术扩增出一条约为500bp的条带。经过序列分析,其长578bp,不含内含子,具有部分开放阅读框(177bp)、终止密码子(TGA)和poly(A)尾巴(11bp),共编码58个氨基酸。该序列及其所编码的氨基酸与其他植物ζ-胡萝卜素脱氢酶基因均具有较高的同源性。该基因已提交GenBank数据库,登录号为GU075728。     

蛇床子素对L-和N-型钙通道的影响

目的：比较蛇床子素对不同钙通道亚型的作用差异。方法：首先在tsA201细胞上瞬时转染Cavl．2,Cav1.3,Cav2．2e[37a],和Cav2．2e[37b]通道,然后采用全细胞膜片钳技术,记录tsA201细胞上的钙电流,并观察蛇床子素对各种钙通道亚型的影响。结果：蛇床子素可以浓度依赖性抑制Cav1．2和Cav1.3电流,抑制的半有效浓度分别为162．1μmol·L-1和56．2μmol·L-1．此外,蛇床子素对Cav2．2通道也有一定的抑制作用,在300μmol·L-1。的浓度下,抑制38％的Cav2．2e[37a]电流和61％的Cav2．2e[37b]电流,蛇床子素对钙电流的抑制是快速可逆的。蛇床子素在各个测试电位水平均能抑制上述四种钙通道电流,但不改变电流的激活阂值和最大峰值电流的激活电压。结论：蛇床子素以浓度依赖的方式抑制多种钙通道亚型并表现出不同的亲和力。     

腔内治疗下肢动脉硬化闭塞症的临床研究

目的：下肢动脉硬化闭塞症（arteriosclerosis obliterans,ASO）是血管外科常见疾病,我们拟讨论腔内成形术在ASO治疗中的应用。方法：回顾2008年5月至2010年4月我科收治的76例ASO病例,对手术成功率、手术效果和糖尿病等合并症对疗效的影响进行分析。结果：总体技术成功61例,技术成功率80.3%,Fontaine II期组技术成功36例（成功率92.3%）,明显高于III期（82.1%）和IV期组（22.2%）;合并糖尿病组22例（28.9%）,技术成功15例（成功率68.2%）,低于无糖尿病组的85.2%;结论：腔内成形术是治疗ASO的有效微创手术方法,积极腔内手术干预有助提高早期患者成功率,同时对晚期患者可有效改善症状。     

孢子丝菌病35例临床分析

孢子丝菌病是由申克孢子丝菌引起的皮肤、皮下组织及附近淋巴系统的慢性感染性皮肤病.现对我院2002～2009年35例临床资料完整者进行回顾性分析.1 临床资料1.1 一般资料35例孢子丝菌病患者为2002～2009年我院皮肤科门诊患者.其中男16例,女19例;年龄最小5岁,最大69岁,平均32岁,绝大多数是青壮年;农民21例(60.0%),工人8例(22.9%,其中3例为水道工,4例为园林工),中小学生4例(11.4%),学龄前儿童2例(5.7%);病程最短1个月,最长3 a,平均6个月;发病前曾有明确的外伤史者15例(42.9%),7例述因瘙痒性皮肤病而经常搔抓身体,但否认有抓破,3例近期曾有疖肿、丹毒、脓疱病等友肤感染史.