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41.
Amanda E. Brandon Amanda C. Boyce Eugenie R. Lumbers Monika A. Zimanyi John F. Bertram Karen J. Gibson 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(3):318-324
We have shown that fetuses whose mothers underwent subtotal nephrectomy (STNx) before pregnancy had high urine flow rates and sodium excretions, but lower hematocrits, plasma chloride, and plasma renin levels compared with controls. To see if these functional differences in utero persist after birth and are the result of altered renal development, we studied 8 lambs born to STNx mothers (STNxL) and 10 controls (ConL) in the second week of life. These lambs were of similar body weights, nose–rump lengths and abdominal girths. Their kidney weights were not different (ConL 36.1 ± 1.9 vs. STNxL 39.8 ± 3.3 g), nor were kidney dimensions or glomerular number (ConL 423,520 ± 22,194 vs. STNxL 429,530 ± 27,471 glomeruli). However, STNxL had 30% larger glomerular volumes (both mean and total, P < 0.01) and there was a positive relationship between total glomerular volume and urinary protein excretion (P < 0.05) in STNxL. Despite this change in glomerular morphology, glomerular filtration rate, tubular function, urine flow, and sodium excretion rates were not different between STNxL and ConL, nor were plasma electrolytes, osmolality, and plasma renin levels. Thus while many of the functional differences seen in late gestation were not present at 1–2 weeks after birth, the alteration in glomerular size and its relationship to protein excretion suggests that exposure to this altered intrauterine environment may predispose offspring of mothers with renal dysfunction to renal disease in adult life. Anat Rec, 291:318–324, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
42.
Tetsuya Kawashima Yoshiyuki Yokota Mitsuhiro Yokoyama Hiroshi Itoh 《Pathology international》1993,43(6):304-312
The pathomorphologic features of hypertrophic cardiomyopathy simulating dilated cardiomyopathy in the late stage (HCM-DCM) were compared with those of ordinary hypertrophic cardiomyopathy (HCM). Seven autopsied hearts with HCM-DCM and 11 with HCM were assessed quantitatively using an image analyzer. Unlike HCM, significant left ventricular enlargement and wall thinning were observed in HCM-DCM, and the percentage areas of massive fibrosis and disarray were significantly greater. In HCM-DCM, the disarray was distributed diffusely, whereas massive fibrosis was distributed more intensively in the ventricular septum and anterior wall than in the lateral and posterior wall. Narrowing of intramyocardial small arteries was observed more frequently in HCM-DCM, especially in the ventricular septum and anterior wall, than in HCM. These results suggest that the enlargement and wall thinning of the left ventricle in HCM-DCM are attributable to non-uniform progression of massive fibrosis, which is closely related to small-arterial lesions. 相似文献
43.
Vitamin B2 and flavin cofactors are transported tightly bound to immunoglobulin in human serum. We reasoned that anti-mitochondrial flavoprotein autoantibodies (alpha Fp-AB) present in the serum of patients with myocarditis and cardiomyopathy of unknown aetiology may form immunoglobulin aggregates with these serum proteins. However, immunodiffusion and Western blot assays demonstrated that the flavin-carrying proteins were not recognized by alpha Fp-AB. Apparently the flavin moiety in the native protein conformation was inaccessible to alpha Fp-AB. This conclusion was supported by the absence of an immunoreaction between the riboflavin-binding protein from egg white and alpha FP-AB. Intravenous application of vitamin B2 to rabbits immunized with 6-hydroxy-D-nicotine oxidase, a bacterial protein carrying covalently attached FAD, did not neutralize alpha Fp-AB which had been raised in the serum of the animals. FAD-carrying peptides generated from 6-hydroxy-D-nicotine oxidase by trypsin and chymotrypsin treatment were not recognized by the alpha Fp-AB, but those generated by endopeptidase Lys were. This demonstrates that the epitope recognized by alpha Fp-AB comprises, besides the flavin moiety, protein secondary structure elements. 相似文献
44.
Early biochemical and morphological changes of the rat adrenal medulla induced by xylitol 总被引:1,自引:0,他引:1
Long-term administration of high doses of xylitol and other polyols in rats has been associated with an increase in adrenal medullary hyperplasia and neoplasia. In order to exclude age-related factors and to differentiate between unspecific stress reactions and direct effects of the compound administered, a model was developed for quantifying early adrenomedullary responses. Male SD rats were fed xylitol (10% or 20% in the diet) for 2 and 8 weeks, and early biochemical changes were correlated with a stereological analysis of the adrenal medulla. At first, the in vivo rate of catecholamine (CA) biosynthesis was slightly decreased (at 2 weeks). This was followed by an increase in dopamine--hydroxylase (DBH) activity (at 8 weeks). By that time, the total chromaffin cell volume had increased and the number of chromaffin cells per reference volume had decreased in a dose-dependent way. The total number of chromaffin cells per adrenal gland showed a distinct tendency towards an increase. Adrenal epinephrine and norepinephrine contents were not altered, and both tyrosine hydroxylase and phenylethanolamine-N-methyltransferase activities remained unchanged. These data suggest that continued xylitol administration evoked an inhibitory effect on CA synthesis that, together with stimulation of the adrenal medulla brought about by the compound, resulted in compensatory medullary hypertrophy and hyperplasia. 相似文献
45.
目的研究腺样体肥大患儿血清炎症介质、淋巴细胞亚群表达特征及其与患儿预后的相关性。方法选取浙江中医药大学附属第三医院收治的86例腺样体肥大患儿(观察组)和86例健康儿童(对照组)作为研究对象,采集血液标本测定血清炎症介质及淋巴细胞亚群相关指标,对比两组儿童的测定结果。分析腺样体肥大患儿的肥大程度、腺样体再增生情况,对比不同肥大程度患儿的血清指标,并分析各指标与患儿病情程度及预后(腺样体再增生)的关系。结果观察组患儿肿瘤坏死因子-α(TNF-α)、可溶性白细胞介素-2受体(sIL-2R)及白细胞介素-6(IL-6)水平分别为(492.44±50.56)mg/L、(420.48±61.79)U/ml及(33.65±4.51)pg/ml,对照组儿童分别为(301.22±41.65)mg/L、(236.55±57.90)U/ml及(16.25±3.27)pg/ml,差异均有统计学意义(t=16.004,P<0.05;t=20.311,P<0.05;t=8.995,P<0.05)。观察组CD4+、CD8+及CD4+/CD8+水平分别为(35.75±7.05)、(16.22±2.69)及(1.46±0.67),对照组分别为(34.25±4.53)、(17.62±2.35)及(1.40±0.62),差异均无统计学意义(t=1.036,P>0.05;t=0.905,P>0.05;t=0.823,P>0.05)。相比腺样体中度肥大患儿,重度肥大患儿的TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平明显更高(P<0.05)。相比未增生患儿,腺样体再增生患儿的TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平明显更高(P<0.05)。相关分析显示,患儿腺样体肥大程度与TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平均呈正相关(P<0.05)。患儿腺体再增生与TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平也呈正相关(P<0.05)。结论腺样体肥大患儿的血清炎症介质及部分T淋巴细胞亚群表达显著升高,其与腺样体肥大程度、患儿预后密切相关。 相似文献
46.
目的 :探讨肾性高血压所致肥大心肌组织磷脂酶C(PLC)活性改变在心肌肥大发生发展中的作用。方法 :制作两肾一夹 (two kindneyoneclip ,2KIC)高血压动物模型 ,以未进行两肾一夹者为假手术组。观察术后 1周、2周、4周和 8周时动脉血压 ,心肌肥大指数 ,心肌ACE活性及PLC活性的变化 ;术后 4周给予卡托普利 (captopril) ,观察 8周时动物的动脉血压 ,心肌肥大指数 ,心肌ACE活性及PLC活性的变化。结果 :术后 2周开始发生高血压与心肌肥大 ,心肌ACE活性于术后 2周、4周、8周显著增高 ;PLC活性于术后 2周、4周、8周分别增高 6 4 6 5 % (P<0 0 5 )、81 5 3 % (P <0 0 5 )、97 2 2 % (P <0 0 1) ,术后 4周给予captopril ,至 8周动脉血压、心肌肥大指数、心肌ACE活性及PLC活性均回降至假手术组水平。结论 :肾性高血压所致肥大心肌组织磷脂酰肌醇特异性PLC活性升高 ,AngⅡ可能通过活化的PLC参与心肌肥大的发生过程 相似文献
47.
目的 比较 2药对高血压左室肥厚患者的疗效及运动后对心率、血压的影响。方法 采用随机分组法将 80例高血压左室肥厚的病人分成两组 ,倍他乐克组和硝苯地平组 ,治疗前后查超声心动图 ,测定IVST、PWT及LVMI ,心率及血压。结果 ① 2药降压效果无明显差异。② 2组患者IVST、PWT、LVMI的下降幅度相同。③中度体力活动后 ,倍他乐克组心率增快 9± 2次 ,收缩压、舒张压上升均小于 3kPa(7 5mmHg) ,硝苯地平组心率增快 2 0± 4次 ,2组相比P <0 0 1,具有显著意义 ;收缩压、舒张压上升幅度均为 3 4± 1 2kPa(2 6±9mmHg) ,明显大于倍他乐克组。④结论 2药对高血压患者的左心室肥厚有相似的逆转作用 ,但倍他乐克可减少体力活动时血压及心率的上升 ,对心脏更具有保护作用。 相似文献
48.
目的 :研究Schafer列线图在确定前列腺手术适应证中的作用。方法 :对 45例前列腺增生症 (BPH)患者进行了压力 -流率测定 ,经Schafer列线图和线性被动尿道阻力关系 (Lin -PURR)定量分析BPH患者膀胱出口梗阻 (BOO)程度和逼尿肌收缩强度。结果 :本组患者无BOO和轻度BOO者为 2 0 .0 % ,逼尿肌收缩强度很弱者为 8.9% ,不适合前列腺手术者为 2 8.8%。结论 :对BPH患者术前作出准确的评价 ,在前列腺治疗的方法选择方面有十分重要的意义 相似文献
49.
目的 用组织多普勒技术分析扩张型心肌病 (DCM)室壁运动。方法 选择 DCM患者和正常对照各 30例 ,用组织多普勒技术于胸骨旁长轴检测室间隔及左室后壁中间段短轴方向心肌运动速度 (MV) ,并计算心肌运动速度阶差 (MVG) ;经心尖窗检测左室前、后、下、侧壁和前、后室间隔中间段长轴方向 MV。结果 DCM组患者有 4种 MV频谱异常表现 ,且 MV明显低于对照组 (P<0 .0 5 ) ,并以长轴为甚 ;MVG明显减低 (P<0 .0 5 ) ;室壁各种速度差异消失。结论 组织多普勒技术可定量反映 DCM患者室壁运动异常 相似文献
50.
目的 :评价氯沙坦、福辛普利、氨氯地平对自发性高血压大鼠 (SHR)心肌细胞凋亡及左室重构的效应。方法 :将 40只 16周龄SHR随机分为氯沙坦治疗组 (SHR -L)、福辛普利治疗组 (SHR -F)、氨氯地平治疗组 (SHR -A)及空白对照组 (SHR -C)。采用末端脱氧核糖核苷酸转移酶介导dUTP缺口末端标记、放免及病理检查方法对SHR治疗 8周、16周心肌细胞凋亡指数 (APOI)、血浆和组织血管紧张素II(PAngII,MAngII)及左室重构指标检测。结果 :①各治疗组治疗 8周、16周收缩压均明显下降 ,组间差异无显著性 ;各治疗组左室重量 (LVW)、左室重量指数 (LVMI)均有显著性改善 ,SHR -F组治疗 16周较其他两组LVMI显著减低。②仅SHR -F组治疗 8周APOI显著性下降 ,治疗 16周各治疗组APOI均有显著下降 ,尤以SHR -F组下降明显。③SHR -L组治疗 8周及 16周PAngII,MAngII显著增加。SHR -F组治疗 8周MAngII显著下降 ,治疗 16周SHR -F ,SHR -A两组MAngII均明显下降 ,且前组较后组下降显著 ,但对PAngII无明显影响。结论 :3药物均能有效逆转心脏肥厚及抗心肌细胞凋亡 ,其中以福辛普利显著。上述作用可能是拮抗心肌组织肾素 -血管紧张素 -醛固酮系统的效应。 相似文献