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11.
秦岭川金丝猴冬季和春季在自然栖息地的空间利用   总被引:2,自引:2,他引:2  
2000年9月到2003年3月共计197天的时间里,我们采用目标动物取样法(Focalanimalsampling)和行为的全事件记录法(Alloccurrencesampling)对一群生活在秦岭北坡周至保护区内的秦岭金丝猴(Rhinopithecusroxellana)在自然栖息地内空间利用的进行了研究。当猴群在离开人工投食区进行自由活动时我们开始收集数据。结果表明:秦岭川金丝猴在不同年龄性别组的个体对植被的空间利用明显不同,它们花费每天活动的14%的时间在地面上活动,53%时间在树叉处活动,33%的时间在树冠中间活动。与其它年龄性别个体相比,成年雄性有27%的观察时间在地上活动,并且20%的取食时间或29%的休息时间是在地上的,明显地高于其它年龄性别组的个体。群体迁移时,成年雄性有53%的时间在地上移动,而只有13%的时间是在树冠层移动的。在通过不同树冠的时候,成年雄性经常会同时抓住两边再把身体摆过去。它们也经常下到地上迁移而回避在树间跳跃。相比之下,亚成年雌性和青少年猴更加经常地在低植被层和树冠层中找食和休息。它们明显地比成年猴更加频繁地在树冠中移动,却很少下地。它们还经常使用跳跃的方式通过树冠间的空隙。从观察到摔下树的事例分析,青少年猴从树上摔下来的风险比成年猴大。本文进而讨论了影响秦岭金丝猴空间分布和移动的因素,比如说身体的重量等.  相似文献   
12.
The present study investigated the relationship between Chinese reading skills and metalinguistic awareness skills such as phonological, morphological, and orthographic awareness for 101 Preschool, 94 Grade-1, 98 Grade-2, and 98 Grade-3 children from two primary schools in Mainland China. The aim of the study was to examine how each of these metalinguistic awareness skills would exert their influence on the success of reading in Chinese with age. The results showed that all three metalinguistic awareness skills significantly predicted reading success. It further revealed that orthographic awareness played a dominant role in the early stages of reading acquisition, and its influence decreased with age, while the opposite was true for the contribution of morphological awareness. The results were in stark contrast with studies in English, where phonological awareness is typically shown as the single most potent metalinguistic awareness factor in literacy acquisition. In order to account for the current data, a three-stage model of reading acquisition in Chinese is discussed.  相似文献   
13.

Background

With market-oriented economic and health-care reform, public hospitals in China have received unprecedented pressures from governmental regulations, public opinions, and financial demands. To adapt the changing environment and keep pace of modernizing healthcare delivery system, public hospitals in China are expanding clinical services and improving delivery efficiency, while controlling costs. Recent experiences are valuable lessons for guiding future healthcare reform. Here we carefully study three teaching hospitals, to exemplify their experiences during this period.

Methods

We performed a systematic analysis on hospitalization costs, health-care quality and delivery efficiencies from 2006 to 2010 in three teaching hospitals in Beijing, China. The analysis measured temporal changes of inpatient cost per stay (CPS), cost per day (CPD), inpatient mortality rate (IMR), and length of stay (LOS), using a generalized additive model.

Findings

There were 651,559 hospitalizations during the period analyzed. Averaged CPS was stable over time, while averaged CPD steadily increased by 41.7% (P<0.001), from CNY 1,531 in 2006 to CNY 2,169 in 2010. The increasing CPD seemed synchronous with the steady rising of the national annual income per capita. Surgical cost was the main contributor to the temporal change of CPD, while medicine and examination costs tended to be stable over time. From 2006 and 2010, IMR decreased by 36%, while LOS reduced by 25%. Increasing hospitalizations with higher costs, along with an overall stable CPS, reduced IMR, and shorter LOS, appear to be the major characteristics of these three hospitals at present.

Interpretations

These three teaching hospitals have gained some success in controlling costs, improving cares, adopting modern medical technologies, and increasing hospital revenues. Effective hospital governance and physicians'' professional capacity plus government regulations and supervisions may have played a role. However, purely market-oriented health-care reform could also misguide future healthcare reform.  相似文献   
14.
ATP结合盒式运载蛋白A1(ATP-binding cassette transporter A1,ABCA1)是近年来发现的极其重要的脂质转运大分子膜蛋白,它可将过量胆固醇从细胞内向细胞外输送到载脂蛋白并包装成高密度脂蛋白(HDL)的膜蛋白,促进胆固醇的逆转运.初步研究转录因子ATF6对ABCA1的表达调控,结果发现,ATF6在人胚胎肾细胞HEK293内剂量依赖性地调节ABCA1基因转录及蛋白质表达. ATF6调节ABCA1与内质网应激信号通路无关. 启动子序列缺失与突变分析表明ATF6作用区位于ABCA1启动子上游-156~-928bp之间, 可能需要E-box的参与,但不需要DR4元件.进而,动物试验结果显示用腺病毒在C57小鼠肝脏过表达ATF6,在mRNA水平上调ABCA1. 本文的研究发现了ATF6新的功能以及调控ABCA1的新机制.  相似文献   
15.
Amniotic fluid cells (AFCs) are routinely obtained and expanded in vitro for prenatal diagnosis; nevertheless current knowledge about their properties is limited. The detailed mechanisms underlying normal pregnancies are yet to be discovered. The goal of this study was to identify the immunological aspects of AFCs including cytokine production and human leukocyte antigen (HLA) expression, and to discuss its implication for pregnancy. Eighty-six samples of AFCs were determined for HLA expression before and after culture. Cytokine production was measured with flow cytometry in AFC culture supernatants. Treatment of interferon (IFN)-gamma on induction of HLA-DR expression in cultured AFCs was also investigated. Data indicated that both fresh and cultured AFCs express HLA-I, HLA-G, but not HLA-DR, and the cultured AFCs predominately produce the cytokine interleukin (IL)-6. Importantly, we observed that IFN-gamma could induce HLA-DR expression on cultured AFCs in a dose-dependent manner. Taken together, our results indicated that AFCs are functionally active cells and are significant in pregnancy.  相似文献   
16.
野生动物在长期进化中形成特定的行为模式以适应特定的生存环境。灵长类的位置行为研究对于理解灵长类进化、适应性的多样化以及生态学和解剖学十分关键。该文对已有文献进行了综述,针对位置行为的分类、季节性、以及具体地点和年龄性别差异性进行了总结,分析了灵长类位置行为的发展、特征以及研究现状,以期对今后非人灵长类位置行为的研究提供借鉴和参考,从而促进我国灵长类行为生态学理论体系的发展。  相似文献   
17.
黄连木雌、雄株内源植物激素和POD同工酶的比较   总被引:1,自引:0,他引:1  
为揭示黄连木(Pistacia chinensis Bunge)不同性别植株的生理差异,以雌株和雄株叶片为试材,对叶片赤霉素(GA3)、脱落酸(ABA)、吲哚-3-乙酸(IAA)、亚精胺(Spd)、精胺(Spm)和腐胺(Put)含量变化及过氧化物酶同工酶进行了测定。结果表明,黄连木雌、雄株叶片GA3含量在6至9月均达到极显著差异,含量均在10月8日达到最大值,分别为100.9μg/g FW和92.9μg/g FW;雄株叶片ABA含量均高于雌株,雌、雄株叶片ABA含量在5月21日和7月8日达到极显著差异,5月21日均为最小值,含量分别为222.0 ng/g FW和340.1 ng/g FW;雄株叶片IAA含量均高于雌株,雌、雄植株叶片中IAA含量在8月8日达到极显著差异,9月8日达到最大值,分别为984.8 ng/g FW和1000.6 ng/g FW;雌株GA3/ABA的比值在7月至9月极显著高于雄株,9月8日差异值最大,为42.8;雌、雄株叶片IAA/ABA在5月21日差异值最大,为0.54;雌、雄株叶片Spd含量存在显著或极显著差异,均在7月8日达到最大值,分别为47.9μg/g FW和42.8μg/g FW;雄株叶片Spm含量均大于雌株,雌、雄株叶片Spm含量在10月8日达到极显著差异,均在7月8日出现最大值,分别为24.3μg/g FW和34.5μg/g FW;雄株叶片Put含量在各个时期均低于雌株,雌、雄株叶片Put含量除5月21日外,存在显著或极显著差异,在9月8日均达到最大值,分别为156.0μg/g FW和135.1μg/g FW。雌、雄株叶片、叶柄过氧化物酶同工酶有显著差异,雌株叶片过氧化物酶同工酶有5条带,分别为POD-1、POD-2、POD-3、POD-4、POD-5;雄株叶片只有4条带,分别为POD-2、POD-3、POD-4、POD-5;雌株叶柄内的过氧化物酶同工酶有4条带,分别为POD-1’、POD-3’、POD-4’、POD-5’,雄株叶柄内的过氧化物酶同工酶有3条带,分别为POD-2’、POD-4’、POD-5’。POD-1为雌株叶片特有条带,POD-1’、POD-3’为雌株叶柄特有条带,POD-2’为雄株叶柄特有条带。通过试验得出,黄连木叶片中ABA、IAA、Spd、Spm和Put含量与性别有关,叶片和叶柄的POD同工酶条带也是鉴别黄连木性别的有效指标。  相似文献   
18.
黑腹果蝇Drosophila melanogaster、家蚕Bombyx mori、意大利蜜蜂Apis mellifera和冈比亚按蚊Anopheles gambiae等昆虫的基因组测序已经基本完成,蛋白质组学技术将是阐明这些基因组功能的重要工具。本文综述了应用差异蛋白质组学技术在昆虫诱导性免疫、抗性机制和分子病理研究方面取得的一些成果:(1) 细菌、真菌、脂多糖或机械损伤诱导的昆虫血淋巴或血细胞来源细胞系的蛋白质表达的改变; (2) Bt抗性昆虫中肠刷状缘膜和抗锥虫采采蝇Glossina morsitans唾液腺多种蛋白质表达的改变; (3)化学农药处理和姬蜂Chelonus inanitus携带的多分DNA病毒引起的昆虫蛋白质组的变化。最后讨论了昆虫差异蛋白质组学研究的瓶颈与对策。  相似文献   
19.
Dendritic cells (DC) are highly specialized antigen presenting cells that play critical roles as instigators and regulators of immune responses including B cell function, antibody synthesis and isotype switch. In this study, we compared immunotherapeutic effect of IL-10-treated DC (IL-10-DC) via both intraperitoneal (i.p.) and subcutaneous (s.c.) delivery in rats with incipient experimental autoimmune myasthenia gravis (EAMG). Spleen DC were isolated from onset of EAMG on day 39 post-immunization, exposed in vitro to IL-10, and then injected into incipient EAMG at dose of 1 x 10(6) cells/rat on day 5 after immunization. Intraperitoneal administration of IL-10-DC suppressed clinical scores, anti-acetylcholine receptors (AChR) antibody secreting cells, antigen-specific IL-10/IFN-gamma production and T cell proliferation compared to control EAMG rats. Importantly, IL-10-DC, if given by s.c. route, failed to ameliorate clinical sign of EAMG. Simultaneously, T cell proliferation, anti-AChR antibody secreting cells and IL-10/IFN-gamma production had no alteration, as compared to control EAMG rats. Both in vitro and in vivo experiments showed that treatment of IL-10 inhibited the migration of DC toward MIP-3beta and lymph node, indicating that in vitro manipulation of DC with IL-10 alters the migration of DC that influences the therapeutic effect in the treatment of autoimmune diseases. In MG patients, neither the improvement of clinical symptom nor the alteration of immunological parameter was observed through s.c. delivery of IL-10-DC, suggesting the limitation of IL-10-DC in the treatment of MG patients.  相似文献   
20.
 该文应用气象数据、土壤物理属性实测数据、土壤水分分布式动态模型和植被表面净辐射模型的模拟结果,利用多元线性回归分析方法,建立 了植被净第一性生产力模型,实现了鄂尔多斯高原东部砂质荒漠化地区考考赖沟流域尺度上30 m×30 m空间分辨率的植被生产力精确模拟,并 且用植被生产力的野外实测数据对模拟结果进行了验证表明: 实测值与模拟值在固定沙丘、半固定沙丘和样线2上都达到0.05显著性相关水平; 不同位置的实测植被生 产力数据多分布在1∶1直线附近,模拟值与实测值吻合较好;植被生产力实测值与模拟值的相对误差范围为3.22%~ 6.27%,偏斜度范围在-12.84%~4.43%。该文的研究方法可以为流域尺度上植被生产力的精确模拟提供借鉴和参考。  相似文献   
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