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131.
B超引导下子宫内膜消融术治疗更年期功血51例临床分析   总被引:1,自引:0,他引:1  
目的:探讨在B超引导下子宫内膜消融术治疗更年期功血的效果。方法:扩张宫颈至6.5号,吸宫,在B超监视下由子宫右前壁始向外刮凝,依次顺时针方向刮凝宫腔2周。结果:治愈31例(60.8%),有效19例(37.3%),好转1例(1.9%),无效0例。结论:电凝刀子宫内膜消融术与其他更年期功血治疗方法相比,消融的范围及深度由B超监视,安全性高,创伤小,不开刀,恢复快,并且治愈率高,更容易在临床上推广。  相似文献   
132.
目的:通过检测幼年特发性关节炎(JIA)患者血清中的抗RA33抗体,了解抗RA33抗体与幼年特发性关节炎的临床诊断价值。方法:采用酶联免疫固相分析检测81例JIA患儿(女19名,男62名,平均年龄8.6岁,平均病程1.4年)血清中抗RA33抗体、RF,同时以55例儿童系统性红斑狼疮(SLE)等其他关节性疾病或病毒感染患者和49例健康儿童作为对照组。阴阳性结果判断均采用试剂盒推荐的临界值。结果:81例JIA患儿中抗RA33抗体阳性率为11.11%(9/81),RF阳性率为12.35%(10/81),特异性均为91.35%;JIA组与正常对照组抗RA33抗体阳性率比较有统计学意义(P<0.05),与其他关节性疾病对照组比较差异无显著性(P>0.05)。JIA组中抗RA33抗体的检出与RF无相关性(P>0.05);在JIA各亚型中抗RA33抗体主要存在于全身型和多关节型,各占33.3%和25.0%,RF则只出现于多关节型,占62.5%。两者比较有显著性差异(P<0.05)。81例JIA患儿中共有18例关节出现影像学改变,其中4例抗RA33抗体阳性(22.2%),与未发生影像学改变的JIA患儿比较无显著性差异(P>0.05)。结论:抗RA33抗体尚不能作为JIA早期诊断的新的可靠性指标,抗RA33抗体主要见于全身型和多关节型,对JIA的分型有指导意义。  相似文献   
133.
GABAB 受体变构剂药学研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
Y-氨基丁酸B受体(GABAB receptor,GABABR)是最具有药理学意义的药物靶点之一,具有复杂而精细的激活机制.传统的GABABR靶点药物开发集中于激动剂和拮抗剂,这类药物受到多种因素的制约,包括较强的副作用、药物代谢困难、机体耐药性明显等.变构剂结合于正构位点之外,能够调节GABABR异源二聚体亚基或结构域间的相互作用.正向变构剂(positive allosteric modulators,PAMs)和负向变构剂(negative allosteric modulators,NAMs)分别可以提高或降低GABABR的活性,并具有较高的特异性和药物安全性,同时还能够保持GABABR信号在时间和空间上的可控性.变构剂为GABABR靶点药物开发提供了新思路.  相似文献   
134.
Y-氨基丁酸B受体(GABAB receptor,GABABR)是最具有药理学意义的药物靶点之一,具有复杂而精细的激活机制.传统的GABABR靶点药物开发集中于激动剂和拮抗剂,这类药物受到多种因素的制约,包括较强的副作用、药物代谢困难、机体耐药性明显等.变构剂结合于正构位点之外,能够调节GABABR异源二聚体亚基或结构域间的相互作用.正向变构剂(positive allosteric modulators,PAMs)和负向变构剂(negative allosteric modulators,NAMs)分别可以提高或降低GABABR的活性,并具有较高的特异性和药物安全性,同时还能够保持GABABR信号在时间和空间上的可控性.变构剂为GABABR靶点药物开发提供了新思路.  相似文献   
135.
1. Nitrogen (N) processing in streams has been investigated using whole‐stream 15N addition experiments that, in general, have found that a large proportion of added nitrate removed from the water column appears to be assimilated by the stream benthos. The long‐term fate of this retained N is unknown, and of particular interest is the possibility that it becomes denitrified through coupled mineralisation–nitrification–denitrification processes (indirect denitrification). 2. We used in situ chambers to produce highly 15N‐enriched benthic biofilms and removed the chambers to allow biofilms to interact with ambient stream conditions. Nitrogen assimilation and direct denitrification were estimated from the first chamber deployment. Chambers were periodically reinstalled over 4 weeks to measure tracer 15N in ammonium (), nitrate () and dinitrogen (N2), from which we estimated subsequent rates of biotic N transformations, including N mineralisation (ammonification), nitrification and indirect denitrification. We also estimated rates of depuration of 15N tracer from benthic biomass compartments. 3. Nitrate uptake was roughly equivalent in the sand and cobble habitats that dominated the stream. Direct denitrification (denitrification of from the water column) was an order of magnitude higher in cobble habitats than in sand habitats, accounting for c. 26 and 2% of total nitrate uptake in cobble and sand, respectively. 4. Mean residence times of actively cycling organic N in stream benthos (algae and microbes) were 16 days in cobble habitats and 9 days in sand habitats. The difference between habitat types was driven by the influence of N residence time in epilithic biofilms (18 days) on cobbles. 5. Release of enriched 15 was the primary flux of remineralised N, while release of enriched 15 was an order of magnitude less. We detected slight 15N enrichment in dissolved nitrogen gas (N2) in post‐enrichment sampling, indicating that indirect denitrification was taking place. However, indirect denitrification accounted for <0.1% of the assimilated N. 6. These experiments agree with results of whole‐stream 15N additions, in that most added N was assimilated rather than directly denitrified. Assimilation was primarily a short‐term N retention mechanism in this stream, and indirect denitrification of assimilated N accounted for only a minor proportion of the observed 15N loss over time. 7. Remaining possible fates include export of N as particulate organic matter, which may lead to additional storage of assimilated N in downstream habitats, and consumption by grazers.  相似文献   
136.
ABSTRACT We examined home range behavior of female feral pigs (Sus scrofa) in a heavily hunted population on Fort Benning Military Reservation in west-central Georgia, USA. We used Global Positioning System location data from 24 individuals representing 18 sounders (i.e., F social groups) combined with mark-recapture and camera-trap data to evaluate evidence of territorial behavior at the individual and sounder levels. Through a manipulative experiment, we examined evidence for an inverse relationship between population density and home range size that would be expected for territorial animals. Pigs from the same sounder had extensive home range overlap and did not have exclusive core areas. Sounders had nearly exclusive home ranges and had completely exclusive core areas, suggesting that female feral pigs on Fort Benning were territorial at the sounder level but not at the individual level. Lethal removal maintained stable densities of pigs in our treatment area, whereas density increased in our control area; territory size in the 2 areas was weakly and inversely related to density of pigs. Territorial behavior in feral pigs could influence population density by limiting access to reproductive space. Removal strategies that 1) match distribution of removal efforts to distribution of territories, 2) remove entire sounders instead of individuals, and 3) focus efforts where high-quality food resources strongly influence territorial behaviors may be best for long-term control of feral pigs.  相似文献   
137.
1. The swallowtail butterfly Battus polydamas archidamas Boisduval, 1936, exhibits polyphenism for pupal coloration (green and brown). It is distributed across arid regions with winter rains and is monophagous on Aristolochia plants, which emerge after the winter rains and dry out the during summer. Thus, day length does not covary positively with host plant productivity. It was hypothesised that pupal colour was driven by food availability, not photoperiod. The benefits of pupal coloration matching the colour of pupation sites in terms of field survival were also investigated to evaluate the adaptive value of pupa colour. 2. Larvae were reared under a factorial array of two photoperiods (LD 10:14 h and LD 14:10 h) and two food availability regimes (leaves ad libitum and available every other day) to assess the frequency of green and brown pupae. Field survival of green and brown pupae was quantified in three commonly used habitats that differ in background coloration (cacti, rocks and shrubs). 3. Food availability determined pupal colour. Larvae in the ad libitum regime resulted mostly in green pupae, while those with restricted food were mostly brown. In contrast, photoperiod did not influence pupal colour. Survival probability of pupae placed on cacti was higher than those placed on rocks and shrubs, and the lowest predation risk across habitats was for green pupae on cacti. 4. Food availability plays a major role in the seasonal polyphenism for pupal colour of specialist butterflies inhabiting arid environments with winter rains.  相似文献   
138.
湖南瓦乡人体质特征研究   总被引:2,自引:0,他引:2  
本文对308例(男156例,女152例)世居在湖南省沅陵县的瓦乡人进行了70项体质人类学指标(观察项目25项,测量项目45项)的调查, 并计算了21项体质指数, 对部分指数进行了分型统计。结果表明: 湖南瓦乡人毛发浓密, 黑而平直; 上睑皱褶出现率较高, 眼裂开度中等, 上斜型眼裂; 少蒙古褶; 鼻根较高, 鼻梁男多直形、女多凹形, 鼻基上翘, 鼻翼高度中等; 口裂宽度中度, 上唇皮肤部多正唇, 红唇较厚; 耳壳多椭圆或卵圆形, 耳垂形状多圆形。体质特征表现为身材矮短, 体型中间型; 窄肩型; 中腿型; 超狭面型; 圆头型、高头型、中头型; 中鼻型。与我国南方其他27个少数民族群体的头面部及身高10项测量值进行聚类分析, 结果显示湖南瓦乡人体质特征与云南独龙族及拉祜族最接近, 与广西傈僳族、广西侗族及湘西土家族次之。湖南瓦乡人属于蒙古人种的南亚类型, 具有现代黄种人的容貌特征。  相似文献   
139.
湖南侗族的手纹研究   总被引:2,自引:0,他引:2  
报道了湖南通道侗族337例正常人的指纹型、总指纹嵴数(TFRC)、a-b纹嵴线(a-bRC)、atd角、轴三角百分距(tPD)、大鱼际纹、小鱼际纹、指间区纹、掌褶纹、掌纹主线横向指数(MLIT)等手纹参数正常值,并与侗族不同人群和湖南周边不同民族进行了比较,发现湖南侗族手掌真实花纹和掌褶纹分布频率与湖南周边其他已研究过的民族和侗族群体存在明显差异。  相似文献   
140.
为了开发利用资源丰富的青稞麸皮,分析了青稞麸皮油的脂肪酸组成并研究了其对高血脂症大鼠的降血脂作用.通过GC-MS分析,从青稞麸皮油中检测到了10种脂肪酸,并发现其亚油酸含量为75.08%.在青稞麸皮油降血脂实验中,选用24只雄性SD大鼠随机分为空白对照组、高脂模型组和青稞麸皮油组,除空白对照组饲喂普通饲料外,其余各组饲喂高脂饲料并进行干预实验比较.3周后,高脂模型组血清TC、TG、LDL-C和AI 4项指标均显著高于空白对照组(P<0.05或P<0.01),而HDL-C/TC显著降低(P<0.05);青稞麸皮油组的血清TC、TG、LDL-C和AI 4项指标均显著低于高脂模型组(P<0.05或P<0.01),而HDL-C/TC显著升高(P<0.05).结果表明青稞麸皮油对大鼠的高血脂症和动脉硬化的形成有明显的抑制作用,而造成这一结果的原因可能是青稞麸皮油中的高亚油酸含量.  相似文献   
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