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101.
女性体检人群生殖道病原体的分布   总被引:1,自引:0,他引:1  
目的了解体检妇女人群生殖道感染情况,为女性生殖道感染的防治提供进一步的资料。方法对1157例参加健康体检的妇女的阴道后穹窿及宫颈分泌物标本进行显微镜镜检以检测阴道清洁度、真菌、滴虫等,同时采用培养法对淋球菌、解脲支原体、人型支原体、真菌等进行检测,沙眼衣原体则采用免疫层析法;检测结果进行统计学分析。结果女性生殖道感染的感染率为54.0%,其中混合感染率为9.3%,而清洁度异常率仅为23.8%;前3位病原体依次为解脲支原体(35.3%)、衣原体(22.2%)、真菌(5.5%);年轻妇女组与年老组支原体的检出率差异有显著性(P<0.05)。结论女性生殖道感染情况严重,支原体、衣原体等感染隐匿,加强对育龄妇女的监测尤为重要。  相似文献   
102.
103.
The caecal epithelium of Calicotyle kröyeri consists of a single cell type which functions in the uptake and intracellular digestion of host epidermis and associated mucus. Each cell is columnar with a small basal nucleus and prominent nucleolus. Perinuclear cytoplasm contains narrow profiles of GER and mitochondria with numerous cristae. Golgi complexes are small and indistinct. Most of the cell is filled with vacuoles of heterogeneous content, the largest occupying the cell apex. There is in each cell an apical endocytotic complex comprising cell surface lamellae, apical vesicles and numerous tubular invaginations of the plasmalemma. The limiting membrane of all these components is structurally modified and bears a highly organized array of peg-like structures on its luminal surface. The complex is capable of ingesting particulate food material from the gut lumen for transfer, via vesicles, to the vacuoles for digestion. Most of the vacuoles represent the digestive elements of the cell and, histochemically, are reactive for protein, mucus and carboxylic esterases. Indigestible residues and lipid droplets accumulate in the large apical vacuole and are periodically released to the lumen by exocytosis. Small, undifferentiated caecal cells were occasionally observed in the epithelium, but their development has not been recorded.  相似文献   
104.
Current literature related to the impact of probiotics on the incidence of gastrointestinal tract infections (GITIs) has shown mixed results and no systematic review available with pooled analysis exists. Thus, the aim of this systematic review was to provide contemporary evidence regarding the overall and strain-specific influence of probiotics in preventing GITIs among infants and children attending childcare centres. The review shortlisted 18 RCTs after screening through the initial search results of 779 articles. However, only 15 trials were deemed eligible, addressing at least one outcome in the pooled analysis. It is concluded that the supplementation of probiotics (overall effect) may reduce the risk of GITI episode by 26%, with Lacticaseibacillus paracasei, Limosilactobacillus reuteri and Lacticaseibacillus rhamnosus GG being specifically potent probiotic strains in reducing GITI episode, duration of infection and absence from childcare respectively. There is insufficient evidence to determine the effect of Bifidobacterium animalis subsp. lactis BB-12 based on the findings of the trials included in this review.  相似文献   
105.
实验以初重为(11.33±0.03) g的异育银鲫(Carassius auratus gibelio)为研究对象,分别投喂脂肪水平为4%(L4)、8%(L8)、12% (L12)、16% (L16)和20% (L20)的5种等氮饲料进行为期340d的长养殖周期实验,以探究饲料脂肪水平对长养殖周期异育银鲫生长性能、消化酶活性和脂代谢的影响。期间共取样5次,生长阶段分为63d(D63,幼鱼期)、110d(D110,养成前期)、223d(D223,越冬期)、275d(D275,越冬后)和340d(D340,养成中后期)。实验结果显示,以增重率为评价指标,幼鱼期D63的异育银鲫适宜脂肪水平为8%,养成前期D110的异育银鲫适宜脂肪水平为12%,而其他生长阶段饲料脂水平对增重率无显著影响。饲料脂肪水平对幼鱼期异育银鲫肠道消化酶活性有显著影响,脂肪酶活性随脂肪水平的升高呈现先降低后升高的趋势,幼鱼期(D63)异育银鲫肠道胰蛋白酶和淀粉酶活性高于越冬期和养成中后期的异育银鲫,表明幼鱼期的异育银鲫对脂肪的利用较低。幼鱼期(D63)异育银鲫脂肪合成相关基因pparγ和fas的表达量饲料脂肪水平升高呈先升高后下降的趋势,且在L8组表达量最高,而脂解基因lpl和cpt1a的表达量在低脂组L4显著低于其他各组。pparγ和cpt1a在越冬后期(D275)的表达量随饲料脂肪水平的升高呈现先上升后下降,而fas表达量在L4组显著高于其他组,表明不同生长阶段异育银鲫对饲料脂肪摄入的响应策略不一致,摄入过高或过低均会导致代谢紊乱。适宜的脂水平(8%—12%)可促进幼鱼期和养成前期异育银鲫的生长,增强脂肪利用率和脂代谢能力,而较大规格的异育银鲫对脂肪的变化不敏感。  相似文献   
106.
This study provides the first evidence of pronounced temporary laryngeal descent in a bovid species. An elaborate acoustic display is prominent in male courtship behavior of polygynous Mongolian gazelle. During rut, rounding up of females is accompanied by continuous head‐up barking by dominant males. Throughout the rut their evolutionarily enlarged larynx descends to a low mid‐neck resting position. In the course of each bark the larynx is additionally retracted toward the sternum by 30% of the resting vocal tract length. A geometric model of active larynx movements was constructed by combining results of video documentation, dissection, skeletonization, and behavioral observation. The considerable distance between resting position and maximal laryngeal descent suggests a backward tilting of the hyoid apparatus and an extension of the thyrohyoid connection during the retraction phase. Return to the resting position is effected by strap muscles and by the elastic recoil of the pharynx and the thyrohyoid connection. An intrapharyngeal inflation of the peculiar palatinal pharyngeal pouch of adult males is inferred from a short‐time expansion of the ventral neck region rostral to the laryngeal prominence. The neck of adult dominant males is accentuated by long gray guard hairs during the rut. The passive swinging of the heavy larynx of adult males during locomotion gives the impression of a handicap imposed on rutting males. Apparently, this disadvantage becomes outweighed by the profits for reproductive success. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
107.
猪胃肠道黏膜二糖酶的性质   总被引:11,自引:0,他引:11  
研究了猪小肠中麦芽糖酶,蔗糖酶和乳糖酶3种二糖酶的生化性质及活性分布。试验以3头“杜加”生长猪为对象,屠宰并刮取胃底部,十二指肠,空肠上段和回肠黏膜。其中空肠黏膜用于3种二糖酶生化性质的研究,包括酶的最适温度,热稳定性,最适pH ,pH稳定范围和金属离子对酶活性的影响;胃底部,十二指肠,空肠上段和回肠黏膜用于测定3种二糖酶活性以揭示其在胃扬中的分布规律。试验结果表明:麦芽糖酶,蔗糖酶和乳糖酶的最适反应温度分别为50,45和55℃,最适pH分别为6.8,6.5和6.0;乳糖酶的耐热温度(70℃)高于麦芽糖酶和蔗糖酶(50℃);不同pH对3种二糖酶活性影响不大;金属离子Cu^2 和Fe^2 对3种二糖酶均有激活作用;而Mn^2 有抑制作用。此外,Zn^2 能抑制麦芽糖酶活性,提高蔗糖酶活性,而不影响乳糖酶活性。3种二糖酶活性在肠道中由高到低的分布为:空肠,回肠,十二指肠和胃;其中麦芽糖酶在空肠和回肠中活性相近。回肠和空肠黏膜中的麦芽糖酶活性均显著高于十二指肠和胃中的酶活性,十二指肠酶活性显著高于胃;空肠中蔗糖酶和乳糖酶活性显著高于回肠,十二指肠和胃底部。从3种二糖酶活性大小看,胃底部和十二指肠中的麦芽糖酶活性显著高于蔗糖酶和乳糖酶;空肠上段和回肠中的麦芽糖酶活性显著高于蔗糖酶活性,蔗糖酶活性又显著高于乳糖酶。上述结果表明,3种二糖酶的生化性质具有一定的差异,在胃肠道中的活性分布规律相似。  相似文献   
108.
Calanus sinicus aggregate at the depth of 40–60 m (ambient temperature is 16 °C) in the waters of the continental shelf of the Yellow Sea during summer. In animals found in near shore regions, there are changes in digestive gut cells structure, digestive enzyme activity (protease, amylase), and tissue enzyme (alkaline phosphatase (ALP)), which may represent adaptations by this cold-water animal to a sharp seasonal increase in temperature of 6–23 °C. The activities of the digestive enzymes (protease and amylase) are very low in animals at stations near the estuary of Yangtse River, whereas they are relatively high in animals at stations in the central Yellow Sea. During summer, B-cells of the intestine and the villi intestinalis disappear in animals that do not feed at stations near the estuary of the Yangtse River. Respiration rates were undetectable or quite low during summer in C. sinicus from stations near the estuary of the Yangtse River, whereas they were relatively high at stations in the central Yellow Sea. Based upon the morphological characteristics of the digestive gut structure, enzyme levels, respiration rates, and the distribution of C. sinicus, we concluded that C. sinicus might be dormant during summer in the near shore areas of the East China Sea while remaining active in the central Yellow Sea.  相似文献   
109.
幼龄皱纹盘鲍唾液腺和消化腺的超微结构与组织化学   总被引:1,自引:1,他引:0  
以透射电镜观察和组织化学方法研究了45日龄皱纹盘鲍的唾液腺和消化腺。唾液腺由粘液细胞和纤毛细胞组成,粘液细胞含发达的粗面内质网和大量的粘原颗粒,分泌中性和酸性混合粘多糖。消化腺由消化细胞和嗜碱性细胞组成,消化细胞呈现活跃的内吞和细胞内消化,并具蛋白酶和非特异性酯酶活性。嗜碱性细胞含发达的粗面内质网和大量含铁的折光小体,折光小体的电子密度较低。  相似文献   
110.
刺猬消化道嗜银细胞形态与分布   总被引:10,自引:2,他引:8  
楚德昌  邓振旭 《四川动物》2002,21(4):252-254
通过用龙桂开浸银法对刺猬消化道各段进行组织切片观察,结果表明嗜银细胞分布于胃贲门及以下所有消化管,其中胃、十二指肠与小肠末段嗜银细胞分布密度较高,小肠中段及直肠末段密度较低。嗜银细胞分布于消化管壁粘膜层腺体与绒毛,其中在腺体密度较高,在绒毛较低,并且胃、小肠壁固有膜腺体的中、底部密度最高,另外在胃幽门有狭小的高密度分布区。嗜银细胞有锥体形、瓜子形、椭圆形、长梭形、圆形等。锥体形、瓜子形、长梭形多有明显的长突起。嗜银颗粒或充满整个细胞,或集中于突起端或基底部。细胞外常可见到刚释放的嗜银颗粒,特别是锥体形、瓜子形细胞的尖端处常可见到向腺管腔或肠腔释放的嗜银颗粒。  相似文献   
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