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11.
摘要 目的:探讨阿霉素注射剂量对肾病综合征(nehpmtic syndrome,NS)大鼠脂蛋白脂酶和卵磷脂胆固醇酰基转移酶(Leci-thin cholesterol acyltransferase,LCAT)水平的影响。方法:64只SD大鼠随机平分为四组-对照组、小剂量阿霉素组、中剂量阿霉素组与高剂量阿霉素组,四组大鼠经尾静脉一次性注射阿霉素0 mg/kg、2 mg/kg、4 mg/kg、8 mg/kg,检测造模后不同时间点大鼠肾脏脂蛋白脂酶和卵磷脂胆固醇酰基转移酶水平变化情况。结果:小剂量阿霉素组、中剂量阿霉素组与高剂量阿霉素组造模后7 d、14 d、21 d的体重与每日采食量、血肌酐与尿素氮都低于对照组(P<0.05),24 h尿蛋白高于对照组(P<0.05),且存在剂量依赖性,三组间对比差异有统计学意义(P<0.05)。小剂量阿霉素组、中剂量阿霉素组与高剂量阿霉素组造模后21 d、28 d的肾脏脂蛋白脂酶和卵磷脂胆固醇酰基转移酶相对表达水平低于对照组(P<0.05),且存在剂量依赖性,三组间对比差异有统计学意义(P<0.05)。结论:小剂量阿霉素可抑制大鼠肾脏脂蛋白脂酶和卵磷脂胆固醇酰基转移酶的表达,能快速有效建立肾病综合征大鼠模型,具有很好的模拟造模效果。  相似文献   
12.
The association of nucleoside triphosphate molecules and calcium ions with purified particles of mycobacteriophage I3 has been documented. The content of nucleoside triphosphate has been determined to be 118 molecules per phage particle by equilibrium dialysis against labelled ATP or 148 molecules per phage particle by the direct determination of labelled nucleoside triphosphate. The concentration of bound Ca2+ exhibited a high degree of variation between different batches, which may be due to the nonspecific binding of Ca2+ by the virus particles. However, the tightly bound Ca2+ not removable by dialysis against calciumspecific chelating agent, showed a constant value of 2985 atoms/phage particle.Abbreviations EGTA Ethylene glycol-bis (-aminoethylether)-N,N1 tetraacetic acid - PFU plaque forming unit - NTP nucleoside triphosphate  相似文献   
13.
目的:观察联合应用舒血宁注射液与前列地尔注射液治疗糖尿病周围血管病变的临床疗效和安全性.方法:以药物降低血糖为基础,舒血宁注射液与前列地尔注射液联合应用于78例糖尿病周围血管病变患者,14天为一个疗程,患者在治疗前后行双下肢动脉彩色多普勒超声检测.结果:治疗后,患者的股动脉、胭动脉及足背动脉管径较治疗前显著增加,血流速度较治疗前明显加快(P<0.05).间歇性跛行症状好转,肢体皮温上升,足背动脉开始有搏动.治疗中无不良反应,亦无出血倾向.结论:舒血宁注射液与前列地尔注射液联合治疗糖屎病周围血管病变是一种安全有效的治疗方法.  相似文献   
14.
目的对比分析妊娠晚期腹腔注射缓冲液对近交系SPF级C57BL/6J(B6)和BALB/c(B/c)小鼠繁育生理的影响。方法 B6和B/c小鼠随机、全同胞兄妹2∶1/1∶1(♀/♂)过夜同居交配,观察交配方式、阴栓与受孕率的关系;受孕鼠在妊娠的第17.5天(妊娠0d=交配后当天)接受腹腔注射酸性磷酸缓冲液,观察注射对母鼠及胚胎的作用及子鼠从离乳到8周的早期生长发育情况。结果 B6较B/c雌鼠的受孕率高(29.4%vs.21.1%[2∶1],33.2%vs.29.7%[1∶1]);交配后10 d~14 d,根据雌鼠增大的腹部、结合体重来判断受孕较观察阴栓更为准确;比较而言,妊娠晚期腹腔注射对B6母鼠及胚胎的影响较大,表现在离乳子鼠数量减少(4.7±3.1 vs.6.1±2.1,P=0.231),离乳时两性别的子鼠体重(g,雌性:11.7±1.1 vs.12.7±1.5;雄性:12.8±1.3 vs.13.6±1.5)显著降低(P均〈0.05)及两品系子鼠早期生长发育的方式显著不同(P=0.000)。结论近交系小鼠繁殖生理存在品系差异;两品系受孕鼠对妊娠晚期腹腔注射的耐受不同,并可能影响实验动物产后的哺乳过程及子鼠的早期生长发育。  相似文献   
15.
Zusammenfassung Das Verzweigungsmuster der terminalen Strombahn des Myocards wird an Zupfpräparaten von 67 Ratten- bzw. Katzenherzen untersucht. Die Gefäße wurden mit Farbsuspensionen gefüllt. Die Schwierigkeiten der vollständigen Darstellung des Kapillarbettes werden diskutiert. Durch aufeinanderfolgende Injektion mit mehreren Farben gelingt es, den arteriellen und venösen Kapillarschenkel unterschiedlich darzustellen. Zur genauen Analyse werden von einzelnen Muskelblättchen ausgedehnte Gefäßkarten hergestellt. Folgende Befunde wurden erhoben: Als feinste Zuleitungsgefäße münden die Präkapillaren in das Kapillarnetz. Ihre Wand enthält nur vereinzelte Muskelzellen. Die Präkapillaren verlaufen parallel oder senkrecht zu den Muskelfasern und teilen sich in gleichwertige Äste (dichotom) oder geben jeweils als Stammgefäß seitliche Äste ab. Die Arteriolen bzw. Präkapillaren anastomosieren nicht miteinander.Die gewöhnlich weiten Venolen bestehen im wesentlichen nur aus einem Endothelrohr. Sie verlaufen zunächst senkrecht zur Muskulatur und münden in abführende, meist längsgerichtete Venen ein. Anastomosen unter den Venolen sind selten.Zwischen Präkapillaren und Venolen sind Kapillarbahnen ausgespannt. Die Kapillaren verlaufen parallel zueinander im Abstand einer Muskelzellbreite und stehen über Queranastomosen miteinander in Verbindung.Die Kapillarwege von Präkapillaren zu Venolen variieren zwischen 100 m und 800 m. Messungen an zwei Herzen ergaben eine mittlere Strecke von 310 m (Ratte) bzw. 400 m (Katze).Die mittlere unverzweigte Kapillarstrecke beträgt im etwas kontrahierten Rattenherzen 65 m, im mäßig erschlafften Katzenherzen 110 m. Da sich höchstens 1/3 der Kapillaräste untereinander zu Maschen verbinden, entsteht ein sehr lockeres Netzwerk.Da benachbarte Kapillaren zu gleichen oder verschiedenen Präkapillaren und Venolen gehören können, sind mehrere Gefäanordnungen im Myocard unterscheidbar:Selten sind reine Gleichstromanordnungen (vgl. Krogh, 1918/19) oder Gegenstromanordnungen (vgl. Diemer, 1965) zu beobachten, bei denen die Kapillaren am gleichen Ort anfangen bzw. enden und benachbarte Kapillaren in gleicher oder entgegengesetzter Richtung durchströmt werden.Überwiegend finden sich asymmetrische Kapillaranordnungen (vgl. Grunewald und Lübbers, 1966), bei denen Kapillaranfänge bzw. -enden gegeneinander versetzt sind und benachbarte Kapillarabschnitte in gleicher oder entgegengesetzter Richtung durchströmt werden. Die morphologischen Befunde zeigen, daß physiologischen Untersuchungen ein gemischtes Versorgungsmodell für den Herzmuskel (Grunewald und Lübbers, 1966) zugrunde gelegt werden kann.
The microcirculatory bed in the myocardium of the rat and the cat
Summary The branching modus of the microcirculatory bed is studied in isolated musclelayers from 67 hearts of rats or cats. The vessels are filled with different dye-suspensions. The methods to demonstrate the capillary bed by perfusion are discussed. It is shown that several dyes injected consecutively can mark the arterial and venous part of the capillary with different colours. For exact analysis maps are prepared of extensive parts of the microcirculatory bed.The precapillaries, the smallest vessels of the distributing system, are provided with only sporadic muscle cells. They run parallel to the muscle fibers or they cross them. They either divide into equal branches in a dichotomous manner or extend as trunk-vessels, from which the capillaries originate as branches. The arterioles and precapillaries don't anastomose with each other. The venous drainage begins with venoles which usually consist of only a wide endothelial tube. They cross the muscle fibers and open into veins which usually extend in the direction of the muscle layers. Anastomoses among the venoles are rare.Between precapillaries and venoles the capillary ways extend. The capillaries run parallel to each other in a distance of one muscle cell. They are connected by short transversal anastomoses. The length of the capillary way between precapillaries and venoles varies between 100 m and 800 m. According to measurements in two hearts there follows an average way of 310 m (rat) or 400 m (cat). The average length of the unbranched capillary segments was 65 m (rat) or 110 m (cat). As at most one third of the capillary branches are combined to mashes there is only a loose capillary-network.Adjacent capillaries may belong to the same or to different precapillaries and venoles, so that there can be differentiated between several different patterns of the microcirculatory bed:There are seldom found pure arrangements in such a way, that adjacent capillaries begin or end at the same place and that the blood flows in equal or contrary directions (cf. Krogh, 1918/19; Diemer, 1965).Mostly asymmetric arrangements are found with capillaries beginning or ending at staggered places and with equal or contrary flow directions in the capillary segments. The morphological results show that the base for physiological studies of the nutrition of the myocardium ought to be a mixed model of the capillary bed.
Die Arbeit entstand unter der Leitung von Herrn Prof. Dr. E. Lindner, Regensburg.  相似文献   
16.
Initial attachment of bacteriophage P22 to the Salmonella host cell is known to be mediated by interactions between lipopolysaccharide (LPS) and the phage tailspike proteins (TSP), but the events that subsequently lead to DNA injection into the bacterium are unknown. We used the binding of a fluorescent dye and DNA accessibility to DNase and restriction enzymes to analyze DNA ejection from phage particles in vitro. Ejection was specifically triggered by aggregates of purified Salmonella LPS but not by LPS with different O-antigen structure, by lipid A, phospholipids, or soluble O-antigen polysaccharide. This suggests that P22 does not use a secondary receptor at the bacterial outer membrane surface. Using phage particles reconstituted with purified mutant TSP in vitro, we found that the endorhamnosidase activity of TSP degrading the O-antigen polysaccharide was required prior to DNA ejection in vitro and DNA replication in vivo. If, however, LPS was pre-digested with soluble TSP, it was no longer able to trigger DNA ejection, even though it still contained five O-antigen oligosaccharide repeats. Together with known data on the structure of LPS and phage P22, our results suggest a molecular model. In this model, tailspikes position the phage particles on the outer membrane surface for DNA ejection. They force gp26, the central needle and plug protein of the phage tail machine, through the core oligosaccharide layer and into the hydrophobic portion of the outer membrane, leading to refolding of the gp26 lazo-domain, release of the plug, and ejection of DNA and pilot proteins.  相似文献   
17.
Evidence is mounting for a relationship between human semen quality and environmental/lifestyle/socioeconomic factors including long term health outcomes such as mortality. The relationship between pre-freeze and post-thaw semen quality in cancer patients and these factors are unknown. Frozen semen from 217 cancer patients was thawed and analysed using a validated CASA method. Post-thaw quality was matched and compared with WHO semen analysis performed prior to storage. The English Indices of Deprivation 2010 were matched with patients and then examined for relationships with pre-freeze and post-thaw semen quality. There is a relationship between semen quality and deprivation in cancer patients. Compared with pre-freeze semen quality, post-thaw semen quality has a stronger relationship with deprivation. Sperm cryopreservation may have potential as a systemic health diagnostic test and is predictive of cancer patient mortality.  相似文献   
18.
Wu G  Song Y  Zheng X  Jiang Z 《Tissue & cell》2011,43(4):246-253
We aimed to investigate the application of adipose-derived stromal cells in the treatment of stress urinary incontinence (SUI). Animal models of stress urinary incontinence were established with Sprague-Dawley female rats by complete cutting of the pudendal nerve. Rat adipose-derived stromal cells were isolated, cultured and successfully transplanted into animal models. Effects of stem cell transplantation were evaluated through urodynamic testing and morphologic changes of the urethra and surrounding tissues before and after transplantation. Main urodynamic outcome measures were measured. Intra-bladder pressure and leak point pressure were measured during filling phase. Morphologic examinations were performed. Transplantation of adipose-derived stem cells significantly strengthened local urethral muscle layers and significantly improved the morphology and function of sphincters. Urodynamic testing showed significant improvements in maximum bladder capacity, abdominal leak point pressure, maximum urethral closure pressure, and functional urethral length. Morphologic changes and significant improvement in urination control were consistent over time. It was concluded that periurethral injection of adipose-derived stromal cells improves function of the striated urethral sphincter, resulting in therapeutic effects on SUI. Reconstruction of the pelvic floor through transplantation of adipose-derived cells is a minimally invasive and effective treatment for SUI.  相似文献   
19.
目的:探讨和评价经纤维支气管镜局部注药对耐药肺结核合并支气管内膜结核患者的可行性和疗效.方法:对120例确诊为耐药肺结核合并支气管内膜结核患者,在进行全身抗结核治疗的同时依据患者志愿,随机分为两组,一组即单纯化疗者,另一组化疗+支气管镜注药组.比较两组病人在临床症状、痰菌阴转、影像学及纤维支气管镜下的疗效差异.结果:耐药肺结核合并支气管内膜结核经全身抗结核治疗辅以支气管镜局部给药,疗效显著优于单纯全身抗结核治疗.结论:使用支气管镜治疗耐药支气管内膜结核,可明显提高疗效、缩短病程,值得在临床上广泛应用.  相似文献   
20.
目的:观察不同剂量的盐酸右旋美托咪定对脑膜瘤切除术患者全麻围拔管期应激反应的影响。方法:60 例ASAI~Ⅱ级,年 龄25-65 岁脑膜瘤切除术患者,随机分为四组,NS、D1、D2 和D3 组,NS 组:静脉泵入等量的生理盐水,D1、D2 和D3组静脉泵注 负荷量均为0.6 滋g/kg 的盐酸右旋美托咪定,各组泵注时间均为10 分钟,输注结束后随之给予维持量,D1组:盐酸右旋美托咪定 维持量0.2 滋g·kg-1·hr-1;D2 组:盐酸右旋美托咪定维持量0.4 滋g·kg-1·hr-1;D3组:盐酸右旋美托咪定维持量0.6 滋g·kg-1·hr-1。观察 并记录拔管时的耐管评分、呛咳程度、警觉/ 镇静评分(OAA/S)、拔管时间及拔管即刻和拔管后3 min 的平均动脉压(MAP)、心率 (HR)及恶心、寒战等不良反应。结果:D3 组患者耐管评分高于D1 组、D2 组和NS 组,呛咳程度轻于D1 组、D2 组和NS 组(P<0. 05);D2、D3 组患者拔管即刻和拔管后3 min 的MDP、HR 均明显低于D1 组(P<0.05);D1、D2 和D3 组不良反应少于NS 组;四组 拔管时间无明显差异。结论:盐酸右旋美托咪定降低脑膜瘤切除术患者全麻围拔管期的应激反应,增强患者对气管导管的耐受 性。  相似文献   
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