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目的探讨低频超声终止妊娠的可能性及其对胎盘形态学的影响。方法利用低频聚焦声束超声(353 kHZ“超声终止早孕治疗机”样机)6种声强各60 s体内直接照射妊娠第10天兔胚胎,妊娠20 d时观察各组胚胎死亡率和胎盘、子宫的形态学变化。结果对照组胚胎总死亡率为12.65%(32/253);照射组中声强30 W/cm2、35W/cm2及≥40 W/cm2组的胚胎死亡率分别为25.00%(12/48)、72.88%(43/59)和100%(64/64、43/43、40/40、35/35)。超声辐照后的即刻改变:光镜下主要为胎盘(绒毛及子宫蜕膜)出血、坏死;电镜下胎盘细胞正常结构消失,子宫平滑肌、内膜上皮细胞中线粒体肿胀。变化随剂量的增加而明显。照射后10 d观察:光镜下见绒毛、蜕膜细胞仍有变性或坏死;电镜下胎盘组织细胞坏死呈致密团块状,子宫内膜上皮、平滑肌及血管内皮细胞均未见异常。结论胎盘较子宫对低频超声更敏感,更易受损,子宫照射后变化轻微且可恢复,低频超声抗早孕是有效而可行的。  相似文献   

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为研究大鼠与家兔骨骼肌各类型肌纤维的数量和二维分布以及生后发育对其影响,取生后2d和2、4、6、8、10周龄(体重10g和32、95、190、280、320g)大鼠及生后2d和2、4、8、12、16、20、24周龄(体重100g和220、400、750、1200、1600、2100、2500g)家兔的比目鱼肌做琥珀酸脱氢酶染色。实验结果表明,大鼠和家兔比目鱼肌纤维被分成Ⅰ型(SO),ⅡX型(FO)和ⅡA型(FOG)3型。使用图像分析系统分析每型肌纤维在生后发育各阶段的相关变化,大鼠和家兔比目鱼肌中:Ⅰ型纤维分布于整块肌肉,其数量随着生后发育而增加。幼体ⅡX型纤维分布在整块肌肉中,其数量随生后发育而减少;ⅡA型分布在肌肉中深层,数量几乎无变化;至成体时只有少量的ⅡX和ⅡA分布在肌表层。整个发育期间未见ⅡB型纤维。ⅡA型纤维直径最大,Ⅰ型中等,而ⅡX型最小。家兔3型肌纤维的平均横切面积比大鼠的大。这些结果表明大鼠和家兔后肢肌各种类型肌纤维的数量比例和分布随生长过程发生改变。  相似文献   

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为研究肉兔肌肉生长发育调控的分子机制,本试验以84日龄齐卡巨型白兔和齐兴肉兔为研究对象,屠宰后取背最长肌组织并提取总RNA,反转录建立c DNA文库,利用Illumina HiSeq 2500测序平台进行测序,并进行序列分析和注释。筛选与肉兔肌肉生长发育相关的信号通路及差异表达基因,最后进行荧光定量PCR验证。结果表明:齐卡巨型白兔和齐兴肉兔背最长肌中显著差异表达基因总数为833个,其中齐卡巨型白兔中显著上调基因325个,显著下调基因508个。KEGG功能注释发现差异基因显著富集到PI3K-AKT通路、癌症通路和黏着斑通路,最终筛选出4个可能与生长发育显著相关的差异表达基因,为进一步对肉兔进行遗传改良提供了理论基础。  相似文献   

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The ontogeny of the axial skeleton, in particular the caudal skeleton, is described from embryos to adult specimens in common wolffish, Anarhichas lupus. The eggs were incubated at constant temperatures of 7.0, 11.0 and 13.0 °C. High egg mortality and structural changes in skeletal development (fusion of parts, absence of distal radials and most of dorsal and anal fin rays, abnormal neural arches and dorsal fin rays) were observed at 13 °C. The frequencies of some anomalies were lower at 11 °C than at 13 °C. The main reason of structural changes of the skeleton at high temperature is the breaking of normal correlations between developmental rates of some cartilaginous structures and other tissues and organs of the embryo. These data suggest an epigenetic mechanism of skeletal evolution.  相似文献   

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Variation in the forefoot skeleton of small-eared shrews (family Soricidae, genus Cryptotis) has been previously documented, but the paucity of available skeletons for most taxa makes assessment of the degrees of intraspecific and interspecific variation difficult. We used a digital X-ray system to extract images of the forefoot skeleton from 101 dried skins of eight taxa (seven species, including two subspecies of one species) of these shrews. Lengths and widths of each of the four bones of digit III were measured directly from the digital images, and we used these data to quantify variation within and among taxa. Analysis of the images and measurements showed that interspecific variation exceeds intraspecific variation. In fact, most taxa could be distinguished in multivariate and some bivariate plots. Our quantitative data helped us define a number of specific forefoot characters that we subsequently used to hypothesize evolutionary relationships among the taxa using the exhaustive search option in PAUP, a computer program for phylogenetic analysis. The resulting trees generally concur with previously published evolutionary hypotheses for small-eared shrews. Cryptotis meridensis, a taxon not previously examined in recent phylogenies, is rooted at the base of the branch leading to the C. mexicana group of species. The position of this species suggests that the mostly South American C. thomasi group shares an early ancestor with the C. mexicana group.  相似文献   

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目的分析不同影响因素对新西兰兔的初次筛选合格率、二次筛选合格率的影响。方法根据2005版《中国药典》进行测定。结果初次筛选结果中,不同季节、体重值、性别、湿度新西兰兔的筛选率都有显著性差异,筛选时间在7~9月、体重值为1.7~2.0 kg、雄性的新西兰兔、在湿度为61~70%的条件下初次筛选率较高;在二次筛选结果中,不同季节、室温、湿度条件下新西兰兔的筛选率都有显著性差异,筛选时间在1~3月、在室温为22.1~23.0℃、湿度为61~70%的条件下新西兰兔的二次筛选率较高。结论在不同影响因素的条件下,新西兰兔的初次筛选合格率、二次筛选合格率均受到影响。  相似文献   

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目的观察不同时间脂肪乳输注使血浆游离脂肪酸(FFA)升高对大鼠葡萄糖输注率(GIR)的影响。方法分别给大鼠输注脂肪乳2、5、7和48 h,行高胰岛素-正血糖钳夹试验评价葡萄糖输注率,测定血浆葡萄糖、FFA。结果与生理盐水输注组比较,2 h脂肪乳输注使血浆FFA升高了2倍(P〈0.01),GIR下降27%(P〈0.05),脂肪乳输注5 h GIR降低了52%(P〈0.01),7 h GIR降低56%(P〈0.01),输注48 h脂肪乳GIR降低58%(P〈0.01),5 h组7、h组及48 h脂肪乳输注组间GIR差异没有统计学意义。结论大鼠输注脂肪乳使FFA浓度达到基础值的3倍左右,可复制出脂毒性胰岛素抵抗的模型,而且胰岛素抵抗达到一定程度后保持恒定。  相似文献   

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Abstract: A specific and sensitive gas chromatographic–mass spectrometric assay for measurement of normetanephrine (NMN) in different rat brain regions is presented. The results show that hypothalamus contains the highest concentrations of the norepinephrine metabolite. An increase of NMN concentrations has been detected in animals killed by decapitation in comparison with microwave–irradiated rats. This finding has to be taken into consideration when NMN is measured in the brain in order to assess the functional activity of noradrenergic neurons.  相似文献   

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目的通过高脂喂养兔制造动脉粥样硬化动物模型,研究G-CSF对不同动脉段内皮形态和功能变化的影响及相互关系。方法30只新西兰成年雄兔随机分4组,分为对照组6只,高脂喂养组、普通及高脂喂养+G-CSF组各8只,分别测定血脂及血清NO浓度,各取胸主动脉、颈总动脉、股动脉,采用病理分析及扫描电镜观察内皮形态的不同变化,同时用RT-PCR方法测定eNOS、ET-1基因的表达了解不同动脉段的内皮功能变化。结果高脂喂养后兔血脂、NO浓度明显升高,病理发现动脉内膜增厚,以大动脉最著,小动脉最次,扫描电镜下内皮细胞的凋亡、变形亦然。ET-1基因表达相对定量次序为胸主动脉〉颈总动脉〉股动脉,eNOS基因反之。应用G-CSF后大动脉内皮功能及形态受到明显影响,但小型动脉变化不大。结论高脂喂养兔能成功制造动脉粥样硬化模型,成模后动脉内皮功能显著受损,其中以大型动脉显著,同时内皮形态出现相应变化。应用G-CSF对全身动脉系统有影响,且动脉越小,影响越小,说明粥样硬化动脉内皮形态与功能改变之间存在必然联系,对G-CSF的反应也不同。  相似文献   

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为了阐明高原低氧对牦牛(Bos mutus)骨骼肌中乳酸脱氢酶(LDH)三种亚基基因(LDHA、LDHB和LDHC)表达的影响,本实验分别选取高海拔(4 200 m)、中海拔(3 200 m)和低海拔(1 900 m)三个海拔位置养殖的临床健康成年雄性牦牛各5头,采用实时荧光定量PCR(qRT-PCR)和蛋白质印迹法检测牦牛骨骼肌中LDH三种亚基基因的m RNA表达和蛋白表达水平。结果表明,随海拔的升高,牦牛骨骼肌中LDHA m RNA的表达逐渐下降;LDHB m RNA先降低后升高,在高海拔组牦牛中表达最高,相对表达量为2.82±0.12,与低海拔组(1.01±0.07)、中海拔组(0.73±0.06)牦牛LDHB mRNA表达量差异显著(P <0.05);LDHC mRNA的表达量随海拔的升高呈下降趋势,且低海拔组(1.10±0.16)、中海拔组(0.86±0.16)、高海拔组(0.69±0.12)组间两两相比均差异显著(P <0.05)。LDHA和LDHC蛋白表达量随海拔的升高呈下降趋势,且LDHA蛋白表达量在低海拔组(1.00±0.00)、中海拔组(0.88±0.0...  相似文献   

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为了研究不同剂量的孕马血清促性腺激素(PMSG)对家兔(Oryctolagus cuniculus f. domesticus)超排后,卵巢组织形态和PMSG对早期胚胎体外发育的影响。将24只家兔分为对照组、50 IU、70 IU和90 IU组,每组6只,对照组不做处理,后3组分别注射50 IU、70 IU和90 IU PMSG和定量100 IU人绒毛膜促性腺激素(HCG)对家兔进行超排处理。解剖后测定卵巢形态和组织参数。利用注射器抽取5ml冲卵液,分别从左右输卵管冲取胚胎至培养皿中,转至细胞培养室对胚胎进行体外培养观察。结果显示,PMSG处理组与对照组相比,随着PMSG注射剂量的增大,家兔卵巢重及宽度和厚度均极显著增大(P<0.01),卵巢长度显著增长(P<0.05),卵巢表面充血,卵泡数增多;另外,随PMSG注射剂量的增大,次级卵泡及其卵母细胞直径、三级卵泡直径均呈减小趋势(P <0.01),三级卵泡中卵母细胞直径呈增大趋势,与对照组相比差异显著(P <0.05);三级卵泡的直径和卵泡的优势化率,70 IU组显著高于对照组及50 IU和90 IU组(P &l...  相似文献   

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摘要 目的:本研究旨在针对高海拔地区低压低氧的特殊性,探讨分析筋膜切开对高海拔挤压伤家兔模型的主要脏器影响,为在高海拔地区进一步研究挤压伤的救治打下基础并提供临床参考依据。方法:选取实验地与饲养地均为高海拔地区西宁的健康成年新西兰家兔,共70 只。随机分为筋膜切开实验组(即A组60只)、对照组(即B组10 只未筋膜切开),4小时后同时解压两组,根据解压后行筋膜切开的时间将A组再分为6组(每组10只),分别定为Ⅰ组(0 h)、Ⅱ组(2 h)、Ⅲ组(4 h)、Ⅳ组(6 h)、Ⅴ组(8 h)、Ⅵ组(10 h);分别检测Ⅰ-Ⅵ组及B组的的静脉血肌酐 Cr、尿素氮 BUN、血钾 K+、乳酸脱氢酶LDH、α-羟丁酸脱氢酶HBDH等生化指标;24 小时后取挤压综合征家兔模型的心肌、肾脏及挤压处的肌肉做病理切片并镜下观察分析;采用SPSS19.0统计软件进行数据分析,以P<0.05为差异有统计学意义。结果:A组、B组挤压4 h后血BUN、Cr、K+、LDH、HBDH差异无统计学意义(P>0.05),两组资料具有可比性。Ⅰ-Ⅵ组与B组的的静脉血BUN、Cr、K+、LDH、HBDH等生化指标组间差异均无统计学意义(P>0.05),各亚组之间在相同时间点生化指标也无统计学差异(P>0.05)。结论:筋膜切开对高海拔挤压综合征家兔模型主要脏器早期恢复中影响不明显。  相似文献   

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Large neutral amino acids (LNAAs) compete with each other for carrier-mediated transport through the blood-brain barrier into the brain. The relative plasma concentration, expressed as the ratio of each LNAA to the sum of LNAAs, is considered the main regulator of brain LNAA concentrations. In order to investigate the consistency of this assumption throughout a 24-h period, we have compared the relationship of plasma LNAAs to brain LNAAs among groups of rats fed diets containing various amounts of protein (in order to obtain a wide range of plasma LNAA levels) at two different phases of the light/dark cycle (0900 and 2100 hours). The relationship between plasma and brain LNAAs was found to be dependent on both diet and the time of day. Similar plasma amino acid concentrations in the morning and in the evening contrasted with different brain concentrations. Furthermore, previous findings that brain LNAA concentrations are influenced by plasma amino acid concentrations were confirmed.  相似文献   

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乌龙岭’龙眼胚胎发育时期特异性蛋白质的变化   总被引:11,自引:0,他引:11  
应用IEF-SDS-PAGE技术分析龙眼胚胎分化发育过程中蛋白质组分的变化。结果表明,在各发育阶段大多数蛋白质组分的电泳图谱基本一致,但也有变化。其中花后38d存在TE1(27.1kD、p,7.3),TE2(17.5kD、pI8.2)2个特异蛋白,45d存在TE3(11.4kD、pI7.6),TE4(13.2kD、pI9.9)2个特异蛋白,52d存在TE5(22.6kD、pI7.2),TE6(18.6kD、pI8.3),TE,(23.5kD、pI3.6)3个特异蛋白。31d胚胎电泳图谱中的蛋白质点数相对较多,表明此时蛋白质旺盛合成与积累,这与蛋白含量的变化基本一致。龙眼胚胎发育过程中特异蛋白的出现或消失.对胚胎的分化发育具有重要作用。  相似文献   

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《Endocrine practice》2022,28(11):1118-1124
ObjectiveThis study aimed to determine the clinical indicators influencing bone mineral density (BMD) of the lumbar spine and femoral neck in patients with pituitary stalk interruption syndrome (PSIS) who underwent multiple hormone replacement therapy (MHRT).MethodsMale patients with PSIS (n = 51) who underwent MHRT for at least 1 year were enrolled in this study. Their BMD parameters were recorded and compared with age-, weight-, and height-matched control adults. In addition, we performed multiple linear regression analysis to correlate clinical parameters with BMD parameters at 2 different sites.ResultsFifty-one patients with PSIS had a mean age of 30.39 ± 5.50 years. After 36 months of treatment, patients with PSIS who underwent MHRT had slightly lower BMD than those in the control group. Multiple linear regression models revealed a positive association between the Z-score values for the lumbar spine with treatment duration (r = 0.453, P < .001), insulin-like growth factor-1 (IGF-1) standard deviation score (SDS) values (r = 0.248, P = .038), and total testosterone level (r = 0.260, P = .036) and a positive association between the Z-score values for the femoral neck with treatment duration (r = 0.425, P < .001) and IGF-1 SDS values (r = 0.338, P = .009).ConclusionCollectively, long-term MHRT improves bone density in patients with PSIS to the normal range. A combination of recombinant human growth hormone replacement is more beneficial to the BMD than non–recombinant human growth hormone treatment. Moreover, serum IGF-1 contributes to femoral and lumbar mineralization, whereas serum testosterone plays a role in lumbar mineralization.  相似文献   

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