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41.
In this study, distribution of metal accumulation and their biological changes of Indian mustard plants (Brassica nigra L.) grown in soil irrigated with different concentration of rayon grade paper effluent (RGPE, 25%, 50%, 75%, 100%, v/v) were studied. A pronounced effect was recorded at 50% (v/v) RGPE on germination of seeds, amylase activity and other growth parameters in Indian mustard plants. An increase in the chlorophyll and protein contents was also recorded at <50% (v/v) RGPE followed by a decrease at higher concentrations of RGPE (>75%). A significant increase lipid peroxidation was recorded, which was evidenced by the increased malondialdehyde (MDA) content in shoot, leaves and seeds in tested plant at all the concentrations of RGPE. This Indian mustard plants (Brassica nigra L.) are well adapted for tolerance of significant amount of heavy metals due to increased level of antioxidants (cysteine and ascorbic acid) in root shoot and leaves of treated plants at all concentration of RGPE. Moreover, it is also important that RGPE should be treated to bring down the metal concentration well within the prescribed limit prior to use in agricultural soil for ferti-irrigation.  相似文献   
42.
王波  汪平  王宏  王涛  杨彦平 《生物磁学》2011,(23):4490-4492
目的:探讨影响侧脑室脑膜瘤手术疗效的因素,从而更好的促进侧脑室脑膜瘤的手术治疗。方法:回顾性分析侧脑室脑膜瘤显微手术30例的临床病理特征与顸后情况,其中KPS〉70分表示为预后良好,KP懿70分表示为预后不良。对各性别、年龄、部位、肿瘤大小、病理分型及术后有无并发症因素与预后进行χ^2检验与用Logistic回归分析其影响因素。结果:单因素分析表明肿瘤部位、病理分型及术后有无并发症对侧脑室脑膜瘤的预后有明显影响,P〈0.05,差异有统计学意义。经Logistic回归分析,最终进入模型的影响因素有2个,它们分别是肿瘤部位和术后有无并发症,其P值均小于0.05。结论:在显微手术下,侧脑室脑膜瘤大部分可以全切并取得了较好的远期疗效。肿瘤部位和术后有无并发症是影响预后的一个重要因素,及时处理并发症能显著地改善预后。  相似文献   
43.
This paper demonstrates that graphical chain models are a suitable statistical tool for investigating the complex structure of a psychiatric disease. The article is motivated by a crucial question arising in psychometric studies on pathological gambling: how are depression and anxiety associated and how do they determine the personality of a pathological gambler? Starting from an initial recursive structure that reduces the complexity of the data, graphical chain models investigate both direct associations and indirect dependencies among the psychometric scales measuring the personality traits. A “behavioral chain” acting in pathological gambling is suggested by the final chain resulted from the Cox and Wermuth variables selection strategy (Cox and Wermuth, 1996). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
44.
A physiologically based model of corticothalamic dynamics is used to investigate the electroencephalographic (EEG) activity associated with tumors of the thalamus. Tumor activity is modeled by introducing localized two-dimensional spatial non-uniformities into the model parameters, and calculating the resulting activity via the coupling of spatial eigenmodes. The model is able to reproduce various qualitative features typical of waking eyes-closed EEGs in the presence of a thalamic tumor, such as the appearance of abnormal peaks at theta ( approximately 3Hz) and spindle ( approximately 12Hz) frequencies, the attenuation of normal eyes-closed background rhythms, and the onset of epileptic activity, as well as the relatively normal EEGs often observed. The results indicate that the abnormal activity at theta and spindle frequencies arises when a small portion of the brain is forced into an over-inhibited state due to the tumor, in which there is an increase in the firing of (inhibitory) thalamic reticular neurons. The effect is heightened when there is a concurrent decrease in the firing of (excitatory) thalamic relay neurons, which are in any case inhibited by the reticular ones. This is likely due to a decrease in the responsiveness of the peritumoral region to cholinergic inputs from the brainstem, and a corresponding depolarization of thalamic reticular neurons, and hyperpolarization of thalamic relay neurons, similar to the mechanism active during slow-wave sleep. The results indicate that disruption of normal thalamic activity is essential to generate these spectral peaks. Furthermore, the present work indicates that high-voltage and epileptiform EEGs are caused by a tumor-induced local over-excitation of the thalamus, which propagates to the cortex. Experimental findings relating to local over-inhibition and over-excitation are discussed. It is also confirmed that increasing the size of the tumor leads to greater abnormalities in the observable EEG. The usefulness of EEG for localizing the tumor is investigated.  相似文献   
45.
Background: Research grade pancreata preserved by the two-layer method (TLM) yield significantly greater numbers of islets than organs stored with University of Wisconsin solution (UW). The goal of this study was to determine whether this would hold true for pancreata that meet selection criteria for clinical grade organs. Methods: Pancreata were chosen based upon a pre-defined set of criteria used for selecting clinical grade pancreata. Thirteen of these organs were preserved in UW and five pancreata were preserved by the TLM. Islets were isolated and evaluated according to the Edmonton protocol. Results: The average preservation time was significantly longer for organ preserved with TLM (9.5 + 2.0 h) as compared to UW (5.8 + 0.6 h, p = 0.015). The pancreata of TLM group resulted in a significant increase in islet yields (3588 ± 500 vs. 2536 ± 312 IE/g pancreas, p<0.05). Visual scoring of islets indicated that islets were better from TLM group (8.3 ± 0.3 vs. 7.3 ± 0.2), and islet survival rates after culture were higher from organs stored with the TLM (87 ± 17 vs. 55 ± 7.4, p<0.05). Other parameters such as viability, insulin content, and stimulation index were similar between the two groups. All the preparations from the TLM group, but only 54% of preparations from the UW group, qualified for islet transplantation. The two recipients receiving islets from TLM group, daily insulin requirements were reduced and C-peptide levels were increased. Conclusion: Compared to storage with UW, exposure of pancreata to the TLM resulted in greater islet yields and improved quality of islets despite longer preservation period. Consequently, pancreata that meet clinical grade status should be preserved by the TLM prior to islet isolation.  相似文献   
46.
Normal angiogenesis is a complex process involving the organization of proliferating and migrating endothelial cells (ECs) into a well-ordered and highly functional vascular network. In contrast, pathological angiogenesis, which is a conspicuous feature of tumor growth, ischemic diseases, and chronic inflammation, is characterized by vessels with aberrant angioarchitecture and compromised barrier function. Herein we review the subject of pathological angiogenesis, particularly that driven by vascular endothelial growth factor (VEGF-A), from a new perspective. We propose that the serious structural and functional anomalies associated with VEGF-A-elicited neovessels, reflect, at least in part, imbalances in the internal molecular cues that govern the ordered assembly of ECs into three dimensional vascular networks and preserve vessel barrier function. Adopting such a viewpoint widens the focus from solely on specific pro-angiogenic stimuli such as VEGF-A to include a key set of cytoskeletal regulatory molecules, the Rho GTPases, which are known to direct multiple aspects of vascular morphogenesis including EC motility, alignment, multi-cellular organization, as well as intercellular junction integrity. We offer this perspective to draw attention to the importance of endothelial cytoskeletal dynamics for proper neovascularization and to suggest new therapeutic strategies with the potential to improve the pathological vascular phenotype.  相似文献   
47.
N. Gupta, N. Dudding, J. Crossley, S.J. Payyappilly and J.H.F. Smith
Outcome of SurePath? cervical samples reported as borderline nuclear changes by cytological subtype and high‐risk HPV status Background: The average borderline rate in cervical cytology samples for English laboratories was 3.8% with the range being 2.0–6.8% at the time of the present study, which was undertaken in order to determine the association between different subtypes of borderline nuclear change (BNC), high‐grade cervical intraepithelial neoplasia (CIN) and high‐risk human papillomavirus (hrHPV) status. Materials and methods: Of 68 551 SurePathTM cervical samples reported in one laboratory over a period of 2 years, 2335 (3.4%) were reported as BNC. hrHPV status was known in 1112 cases (47.6%). The outcome was known only for women with hrHPV‐positive BNC, who were recommended for colposcopy under the National Health Service Cervical Screening Programme sentinel site protocol. Women with hrHPV‐negative BNC were returned to 3‐yearly recall. The cases were subdivided into BNC, high‐grade dyskaryosis cannot be excluded (B‐HG; 105 cases); BNC with koilocytosis (B‐K; 421 cases); BNC with other features of HPV (B‐HPV; 160 cases); and BNC, not otherwise specified (B‐NOS; 426 cases) and were correlated with the histological outcome where available. Results: The study population age ranged from 23 to 65 years. Cases that tested positive for hrHPV by Qiagen HCII assay comprised 78.1%, 81.0%, 73.1% and 67.8% of B‐HG, B‐K, B‐HPV and B‐NOS categories, respectively. CIN2 or worse (CIN2+) was found in 64.6%, 10.0%, 19.7% and 20.1% of hrHPV‐positive cases of B‐HG, B‐K, B‐HPV and B‐NOS, respectively, which was significantly higher in the B‐HG category (P < 0.001) and lower in the B‐K category compared with B‐NOS (p < 0.001) and B‐HPV (p = 0.006) respectively. CIN3+ comprised 55.6%, 6.3%, 26.3% and 19.1% of biopsies in the same categories, respectively. Conclusions: Subtyping BNC is useful, especially B‐K and B‐HG, which, respectively, had the lowest and highest rates of detection of both CIN2+ and CIN3+, confirming that koilocytosis is likely to be associated with transient HPV infection. Women with B‐HG should be referred to colposcopy in the absence of HPV triage.  相似文献   
48.
49.
陈宇  傅强  赖凤香  罗举  张志涛  胡国文 《生态学报》2012,32(5):1546-1552
研究了取食分蘖初期、拔节期和孕穗抽穗期稻株上的褐飞虱和白背飞虱成虫的卵巢发育和起飞情况。其中,水稻生育期对褐飞虱的影响相对较小,不同生育期稻株上试虫的卵巢发育级别羽化后的4d内均无显著差异,羽化后第5天的褐飞虱在孕穗抽穗期卵巢发育最快,分蘖初期最慢,拔节期居中。褐飞虱的起飞率在各个生育期均无显著差异。白背飞虱卵巢发育、起飞率均受水稻生育期的显著影响,在水稻分蘖初期,卵巢发育最快,孕穗抽穗期则卵巢发育最慢,拔节期居中,水稻分蘖初期,起飞率最低,孕穗抽穗期起飞率最高,拔节期居中。结果表明,水稻生育期对两种飞虱卵巢发育和起飞行为的影响明显不同。认为水稻生育期对两种飞虱卵巢发育与起飞行为的不同影响,应是水稻田间白背飞虱发生较早、褐飞虱发生较晚的一个重要原因。  相似文献   
50.
目的:研究胆碱酯酶(CHE)在评估乙肝肝硬化患者肝脏储备功能中的应用价值。方法:收集501例肝硬化患者病例,并根据肝脏功能进行Child分级。应用全动自动生化分析仪,以酶速率比色法检测胆碱酯酶(CHE),溴甲酚绿法检测白蛋白(ALB),凝固法检测凝血酶原时间(PTs)。应用方差分析,研究胆碱酯酶(CHE)在不同CHILD分级组别中的肝功能评价意义。应用相关分析方法,比较胆碱酯酶(CHE)与其他肝脏合成指标白蛋白(ALB)、凝血酶原时间(PTs)的相关性。结果:肝硬化患者在严格Child-Pugh分级标准划分而成的ABC三级中,各级胆碱酯酶(CHE)活性逐级明显下降,分别为5469.04±1777.31 U/L(Child A),2935.08±1206.95 U/L(Child B),1810.40±724.72 U/L(Child C),且结果差异有显著意义(F=261.114,P=0.000)。在肝硬化患者中,胆碱酯酶(CHE)与白蛋白(ALB)总体正相关、与凝血酶原时间(PTs)总体负相关。其中Child A级患者中,CHE与ALB成正相关,与PTs负相关。Child B级患者中,CHE与PTs负相关,但与ALB无显著相关性。Child C级患者中,CHE与ALB正相关,但与PTs无显著相关性。结论:胆碱酯酶(CHE)与肝硬化患者肝细胞损害的严重程度相关,可反映肝脏的储备功能,与白蛋白(ALB)、凝血酶原时间(PTs)有同样重要的价值。  相似文献   
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