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31.
Although recent major advances have developed a much better understanding of the pathophysiological pathways, tubulointerstitial fibrosis (TIF) is still currently incurable. Therefore, early detection may mean that the condition is more manageable than it was in the past. C-type natriuretic peptide (CNP) has been found to be a potent vasodilator but a weak natriuretic factor. In addition, CNP has also been believed to be produced in tubular cells and presented as a local modulator with anti-inflammatory and anti-proliferative effects. Elimination of CNP occurs by three main mechanisms, neutral endopeptidase, natriuretic peptide receptor-C and urinary excretion. Among them, the status of urinary CNP excretion in nephropathies is not yet fully elucidated. In the present study, subgroups of rats were subjected to unilateral ureteral obstruction (UUO) or sham operation and observed for 24 h to 3 months. Urinary CNP excretion was significantly enhanced in UUO rats from 24 h to 1 month post-ligation compared to sham-operated rats. Urinary CNP excretion was also markedly higher than CNP concentrations both in abdominal aorta and in renal vein, and almost identical concentrations in these two vessels excluded major renal extraction of circulating CNP of systemic origin. Urinary CNP excretion was negatively correlated with urinary protein concentration, blood urea nitrogen and creatinine, while positively correlated with albumin. In conclusion, the increased urinary CNP excretion is strongly associated with TIF progression, and may serve as an early marker of TIF.  相似文献   
32.
Summary Attempts at the reciprocal cross between Petunia parodii and P. inflata using standard emasculation and pollination techniques failed. Limited pollen tube growth down the style in reciprocal crosses led to reproductive isolation between the self-compatible P. parodii and self-incompatible P. inflata. The interspecific hybrid was successfully produced by bud-pollination of P. parodii with P. inflata as the male parent in 22 percent of attempts, but not in the opposite direction. In vitro pollination of P. parodii ovaries with P. inflata pollen also produced hybrids. The small size of the ovary made it technically impossible to use P. inflata as the female parent for in vitro pollination. The interspecific hybrids were intermediate, as compared to the two parents, for six of the seven plant and flower characters measured. Furthermore, the hybrids had high pollen fertility, set abundant seed upon self-pollination, and readily inter-crossed with the parental species. The results are consistent with a high degree of chromosomal homology in the parental species and with minor genetic divergency leading to reproductive isolation that is pre-zygotic in nature. Overcoming the barriers to cross-incompatibility by practical techniques resulted in fertile interspecific hybrids that segregated for parental characters. The potential value of employing the parental species in somatic hybridization experiments is discussed.Michigan Agricultural Experiment Station Journal Article No. 8404  相似文献   
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34.
Plants have evolved many systems to prevent inappropriate fertilization. Among them, incompatibility is a well-organized system in which pollen germination or pollen-tube growth is inhibited in pistils. Self-incompatibility (SI), rejecting self-pollen, promotes outbreeding in flowering plants. On the other hand, inter-species incompatibility, preventing gene flow among species to restrict outbreeding, usually occurs unilaterally, and is known as unilateral incompatibility (UI). In Brassicaceae, little is known about the molecular mechanism of UI, although S-locus genes involved in recognition of self-pollen have been characterized in the SI system. In the present study, we characterized novel UI observed between members of the same species, Brassica rapa; pollen of Turkish SI lines was specifically rejected by pistils of the Japanese commercial SI variety Osome. The incompatible phenotype of this intra-species UI closely resembled that of SI. Segregation analysis revealed that the pollen factor of this UI was not linked to the S-locus.The revised version was published online in December 2004 with corrections to figure 1.  相似文献   
35.
目的:研究比较双切口双钢板内固定(DIDPIF)与单侧锁定钢板内固定(ULPIF)治疗复杂胫骨平台骨折(CTPF)的疗效。方法:从2010年2月至2015年11月选取在我院接受手术治疗的CTPF患者36例作为研究对象,按随访数字表法平均分为观察组和对照组,观察组接受DIDPIF术式治疗,对照组接受ULPIF术式治疗,比较两组术后固定疗效、手术指标以及术后并发症。结果:观察组术后固定的优良率是83.33%,与对照组的61.11%比较,差异不存在统计学意义(P0.05)。观察组骨折愈合的时间及下地负重的时间均显著短于对照组,差异存在统计学意义(P0.05)。观察组固定术后总并发症的发生率是27.78%,与对照组的38.89%比较,差异不存在统计学意义(P0.05)。结论:DIDPIF术式与ULPIF术式均可较好地治疗CTPF患者,但DIDPIF术式在骨折愈合的时间及下地负重的时间方面均优于ULPIF术式,且不会增加安全风险,值得推广应用。  相似文献   
36.
目的:研究股神经联合坐骨神经阻滞麻醉用于老年单侧下肢手术的麻醉效果及对血流动力学的影响。方法:选取2014年1月到2015年1月我院收治的老年单侧下肢手术患者70例,按照随机数字表法将患者分为研究组和对照组,每组35例,研究组给予股神经联合坐骨神经阻滞麻醉,对照组给予蛛网膜下腔麻醉,比较两组麻醉效果,麻醉前、麻醉15 min、麻醉半小时收缩压(SBP)、舒张压(DBP)、心率(HR),并观察不良反应的发生率。结果:麻醉15 min、半小时后对照组SBP和DBP显著低于研究组,也显著低于麻醉前,比较差异有统计学意义(P0.05),研究组麻醉15 min、半小时后SBP和DBP与麻醉前比较无统计学意义(P0.05),麻醉15 min、半小时后两组HR与麻醉前比较无统计学意义(P0.05);研究组不良反应发生率显著低于对照组,两组比较差异具有统计学意义(P0.05)。结论:股神经联合坐骨神经阻滞麻醉用于老年单侧下肢手术麻醉效果与蛛网膜下腔麻醉相当,对血流动力学影响较少,安全性较高。  相似文献   
37.
In order to explore the application of the precision extracoronal attachment based on three-dimensional finite element stress model in the repair of unilateral mandibular dissociation and loss, the stress distribution of the butment and periodontal tissues when the precision extracoronal attachment was used in unilateral mandibular dissociation and loss was analyzed, so as to provide reference for the application of materials in clinical repair. In this study, the biomechanics of oral cavity and its attachment were analyzed to provide theoretical basis for model construction. Because the degree of periodontal tissue absorption and the number of abutment teeth affected the restoration effect of the coronal precision attachment, the models were established from these two perspectives. The results showed that when the periodontal tissue absorption of both abutment teeth exceeded 1/3, the method of double abutment restoration was not recommended. When three abutments were used, there was a significant decrease compared with the absorption of the periodontal tissue of the double abutment. In clinic, the stress distribution of the distal abutment teeth and its periodontal tissues can be improved by increasing the number of abutment tooth. However, since increasing the number of abutments required an increase in the amount of healthy tooth tissue, it couldn’t be blindly selected in the clinic. After comprehensive consideration, it is appropriate to choose two abutment teeth for restoration.  相似文献   
38.
Preserving upright stance requires central integration of the sensory systems and appropriate motor output from the neuromuscular system to keep the centre of pressure (COP) within the base of support. Unilateral peripheral vestibular disorder (UPVD) causes diminished stance stability. The aim of this study was to determine the limits of stability and to examine the contribution of multiple sensory systems to upright standing in UPVD patients and healthy subjects. We hypothesized that closure of the eyes and Achilles tendon vibration during upright stance will augment the postural sway in UPVD patients more than in healthy subjects. Seventeen UPVD patients and 17 healthy subjects performed six tasks on a force plate: forwards and backwards leaning, to determine limits of stability, and upright standing with and without Achilles tendon vibration, each with eyes open and closed (with blackout glasses). The COP displacement of the patients was significantly greater in the vibration tasks than the controls and came closer to the posterior base of support boundary than the controls in all tasks. Achilles tendon vibration led to a distinctly more backward sway in both subject groups. Five of the patients could not complete the eyes closed with vibration task. Due to the greater reduction in stance stability when the proprioceptive, compared with the visual, sensory system was disturbed, we suggest that proprioception may be more important for maintaining upright stance than vision. UPVD patients, in particular, showed more difficulty in controlling postural stability in the posterior direction with visual and proprioceptive sensory disturbance.  相似文献   
39.
苦参素对单侧输尿管梗阻大鼠肾间质纤维化的保护作用   总被引:2,自引:2,他引:0  
目的探讨苦参素对单侧输尿管梗阻(UUO)大鼠肾间质纤维化的影响及可能机制。方法45只雄性SD大鼠随机分为3组:A假手术组,B单侧输尿管结扎(UUO)组,C治疗组。治疗组在UUO的基础上每天以苦参素100mg/Kg/d腹腔注射。B组和C组于术后第7,14,21,28分别处死5只大鼠,A组于第28天处死大鼠。用PAS及Masson染色法观察肾脏病理改变。用免疫组化法检测转化生长因子β1(transforming growth factor-beta1 TGF-β1),α-平滑肌肌动蛋白(alpha-smooth muscle actin-αSMA),Ⅰ型胶原(collagenⅠColⅠ)的表达。结果与UUO组相比,治疗组梗阻侧肾脏TGF-β1,-αSMA,ColⅠ的表达明显减少,肾小管损害和肾间质纤维化的程度也明显减轻。结论苦参素可通过下调TGF-β1,减少肾小管上皮细胞转分化而减轻肾间质纤维化。  相似文献   
40.
单侧输尿管梗阻法制作大鼠肾间质纤维化模型的改进   总被引:9,自引:0,他引:9  
目的建立改良的大鼠肾间质纤维化模型。方法用单侧输尿管结扎术建立大鼠肾纤维化模型,动态观察4周。治疗的第12、、3周末检测血肌酐、尿素氮含量等指标,观察肾功能变化;4周末采用HE染色、六胺银(periodic acid-silver methenamine,PASM)染色和丽春红染色观察肾组织病理变化。结果模型组大鼠血肌酐、尿素氮均有明显上升;模型组大鼠大部分肾小球呈玻璃样变,硬化的肾小球周围所属肾小管萎缩、基底膜增厚,部分肾小管消失;少数残存的肾小球肥大并周围肾小管扩张严重;肾间质胶原纤维增生和大量炎细胞浸润。结论该模型有明显的肾间质纤维化特征,且死亡率低,适合肾间质纤维化的实验研究。  相似文献   
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