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61.
目的:观察精神分裂症患者血清蛋白因子与PANSS评分的相关性,探讨血清蛋白因子作为生物标志物评估精神分裂症的可能性。方法:选择2015年5月-2018年7月期间我院收治的68例精神分裂症患者为观察组,根据疗效分为显著组(n=22)、有效组(n=35)、无效组(n=11),同期选择健康体检志愿者68例作为对照组。测定各组神经胶质纤维酸性蛋白(GFAP)、脑源性神经营养因子(BDNF)、神经生长因子(NGF)及钙结合蛋白(S100β)等血清蛋白因子水平,并分析观察组治疗后血清蛋白因子水平与阳性与阴性症状量表(PANSS)评分的相关性。结果:观察组治疗前血清BDNF及NGF水平显著低于对照组,而血清S100β与GFAP水平高于对照组(P0.05)。不同疗效组治疗前后BDNF、S100β、GFAP水平比较差异有统计学意义(P0.05),其中显效组的各指标水平最高;不同疗效组治疗前后S100β水平比较差异无统计学意义(P0.05);与治疗前相比,治疗后不同疗效组BDNF、NGF均降低(P0.05)。Pearson相关性分析显示,治疗后,血清BNDF水平与PANSS评分呈正相关,GFAP水平与PANSS评分呈负相关(P0.05),血清NGF、S100β水平与PANSS评分无相关性(P0.05)。结论:精神分裂症患者在患病早期即存在神经营养不良及神经损伤,血清蛋白因子GFAP、BDNF或可作为辅助评价精神分裂症患者的潜在生物标志物。  相似文献   
62.
目的:探讨硫辛酸对阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者睡眠呼吸情况及相关生化指标的影响。方法:选取石家庄市第一医院收治的OSAHS患者60例,采用随机数字表法分为对照组(n=30)和观察组(n=30)。对照组给予常规治疗,观察组在对照组基础上口服硫辛酸胶囊,疗程为12周。对比两组患者的临床疗效、爱泼沃斯嗜睡量表(ESS)评分,睡眠呼吸情况、糖脂代谢、肝功能及氧化应激指标水平。结果:与对照组比较,观察组治疗后的有效率升高,ESS评分降低(P0.05)。与对照组比较,观察组治疗后呼吸暂停低通气指数(AHI)、脉压(PP)降低,最长呼吸暂停时间缩短,血氧饱和度(SaO2)水平升高(P0.05)。与对照组比较,观察组治疗后空腹血糖、餐后2 h血糖、谷草转氨酶(AST)、甘油三酯(TG)、谷丙转氨酶(ALT)、总胆固醇(TC)、碱性磷酸酶(ALP)、丙二醛(MDA)水平降低,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)水平升高(P0.05)。结论:采用硫辛酸治疗OSAHS患者具有较好的临床疗效,能够改善患者睡眠呼吸情况及肝功能,调节糖脂代谢,降低氧化应激反应。  相似文献   
63.
64.
Hearing loss is one of the most common sensory disorders in humans and has a genetic cause in 50% of the cases. Our recent studies indicate that nonsyndromic hearing loss (NSHL) in the Saudi Arabian population is genetically heterogeneous and is not caused by mutations in GJB2 and GJB6, the most common genes for deafness in various populations worldwide. Identification of the causative gene/mutation in affected families is difficult due to extreme genetic heterogeneity and lack of phenotypic variability. We utilized an SNP array-based whole-genome homozygosity mapping approach in search of the causative gene, for the phenotype in a consanguineous Saudi family, with five affected individuals presenting severe to profound congenital NSHL. A single shared block of homozygosity was identified on chromosome 19p13.3 encompassing GIPC3, a recently identified hearing loss gene. Subsequently, a novel mutation c.122 C>A (p.T41K) in GIPC3 was found. This is the first report of GIPC3 mutation in a Saudi family. The presence of the GIPC3 mutations in only one of 100 Saudi families with congenital NSHL suggests that it appears to be a rare cause of familial or sporadic deafness in this population.  相似文献   
65.
Stimulation of bioprocesses by ultrasound   总被引:3,自引:0,他引:3  
Ultrasound (US) has become a ubiquitous technological process in a large variety of scientific disciplines. However, little information exists on the use of ultrasound to enhance biological processes and/or processing and consequently this paper provides an overview of work reported to date on this topic. This review provides a brief introduction to ultrasound and the history of ultrasound as applied to bioprocesses. This is followed by a discussion of the influence of US on discrete enzyme systems, enzymes used in bioremediation, microbial fermentations and enzymatic hydrolysis of biopolymers. Augmentation of anaerobic digestion by US is then considered along with enhancement of enzymes in food science and technology. The use of ultrasonically stimulated enzymes in synthesis is then considered and other relevant miscellaneous topics are described. It is concluded that the precise mechanism of action of US in bio-processing remains to be elucidated though a variety of plausible suggestions are made.  相似文献   
66.
This paper investigated whether a single Hormonal Growth Promotant (HGP) adjustment in the Meat Standards Australia (MSA) beef grading model adequately predicted consumer eating quality of beef from cattle treated with different HGP formulations. This paper used consumer sensory data from two experiments. In experiment one, a total of 300 steers were allocated to three treatments; control (CON-100-F), 100 day oestradiol only HGP (OES-100-F), or a combination of trenbolone acetate and oestradiol HGP (TBA+OES-100-F) and finished in a feedlot for 73 days. In experiment two, a total of 200 steers were allocated either control or 400 day oestradiol only HGP treatments and finished on pasture for 389 days. Steers were slaughtered by finishing regime and carcass traits recorded. The anterior and posterior portions of the m. longissimus lumborum (LL-A and LL-P, respectively) and m. gluteus medius (GM) were collected and aged for five or 35 days. Grilled meat samples were scored for tenderness, juiciness, liking of flavour and overall acceptability using untrained consumers. Sensory scores were weighted by 0.3. 0.1, 0.3 and 0.3, respectively and summed to calculate a meat quality (MQ4) score. Residual MQ4 scores were calculated (observed MQ4 minus the predicted MQ4 score). The MSA model accounts for varied impacts of different HGPs on eating quality through a single HGP adjustment, and indirect impacts on carcass traits. For the majority of the HGP treatment samples, the residual MQ4 scores were not different to zero (5/18), or were positive i.e. the MSA model under-predicted these samples (11/18). Under-prediction was predominately for 35 day aged (7/9) and GM HGP treatment samples (6/6) and was considered low, with the majority less than ±5 MQ4 units. Under-prediction could be considered as advantageous through providing an additional safeguard to protect the interests of the consumers, rather than if the model had over-predicted and resulted in a more negative eating quality experience than expected. Some over-prediction was observed in the CON-100-F and TBA+OES-100-F treatment samples, which may be due to factors such as genetic variation and/or production environment. Minimal bias was observed when residual MQ4 was regressed against predicted MQ4 for the range of feeding regimes, muscles, ageing periods and treatment groups. This study showed that a single HGP adjustment in the MSA beef grading model, combined with the indirect effects of the different HGP formulations on carcass traits, provided a reasonable prediction of meat eating quality for different HGP formulations.  相似文献   
67.
摘要 目的:观察大柴胡汤对轻症急性胰腺炎(MAP)患者辅助性T细胞17 /调节性T细胞(Th17/Treg)免疫平衡和血清水通道蛋白(AQP)的影响。方法:按照随机数字表法,将天津中医药大学第一附属医院2020年4月~2022年4月期间收治的95例MAP患者分为对照组(西医基础治疗,47例)和研究组(对照组基础上接受大柴胡汤治疗,48例)。对比两组中医证候积分、Th17/Treg免疫平衡、AQP1、AQP5、AQP6和实验室指标。结果:两组治疗7 d后两胁胀痛,矢气则舒,右中上腹痛,恶心呕吐,抑郁易怒,嗳气呃逆,大便不畅评分均下降,且研究组低于对照组(P<0.05)。两组治疗7 d后Treg细胞比例升高,Th17细胞比例、Th17/Treg下降,且研究组的改善幅度大于对照组(P<0.05)。两组治疗7 d后AQP1、AQP5、AQP6升高,且研究组高于对照组(P<0.05)。两组治疗7 d后淀粉酶(AMY)、脂肪酶(LIP)、C反应蛋白(CRP)下降,且研究组低于对照组(P<0.05)。结论:大柴胡汤治疗MAP疗效确切,可以缓解患者的临床症状,有效改善MAP患者Th17/Treg免疫平衡和血清AQP1、AQP5、AQP6水平。  相似文献   
68.
The impact of phenolic compounds (around 3.2 g/L) resulted in a completely failed performance in a mesophilic UASB reactor treating coal gasification wastewater. The recovery strategies, including extension of HRT, dilution, oxygen-limited aeration, and addition of powdered activated carbon were evaluated in batch tests, in order to obtain the most appropriate way for the quick recovery of the failed reactor performance. Results indicated that addition of powdered activated carbon and oxygen-limited aeration were the best recovery strategies in the batch tests. In the UASB reactor, addition of powdered activated carbon of 1 g/L shortened the recovery time from 25 to 9 days and oxygen-limited aeration of 0-0.5 mgO2/L reduced the recovery time to 17 days. Reduction of bioavailable concentration of phenolic compounds and recovery of sludge activity were the decisive factors for the recovery strategies to tackle the impact of phenolic compounds in anaerobic treatment of coal gasification wastewater.  相似文献   
69.
Although radar has been used in studies of bird migration for 60 years, there is still no network in Europe for comprehensive monitoring of bird migration. Europe has a dense network of military air surveillance radars but most systems are not directly suitable for reliable bird monitoring. Since the early 1990s, Doppler radars and wind profilers have been introduced in meteorology to measure wind. These wind measurements are known to be contaminated with insect and bird echoes. The aim of the present research is to assess how bird migration information can be deduced from meteorological Doppler radar output. We compare the observations on migrating birds using a dedicated X‐band bird radar with those using a C‐band Doppler weather radar. The observations were collected in the Netherlands, from 1 March to 22 May 2003. In this period, the bird radar showed that densities of more than one bird per km3 are present in 20% of all measurements. Among these measurements, the weather radar correctly recognized 86% of the cases when birds were present; in 38% of the cases with no birds detected by the bird radar, the weather radar claimed bird presence (false positive). The comparison showed that in this study reliable altitudinal density profiles of birds cannot be obtained from the weather radar. However, when integrated over altitude, weather radar reflectivity is correlated with bird radar density. Moreover, bird flight speeds from both radars show good agreement in 78% of cases, and flight direction in 73% of cases. The usefulness of the existing network of weather radars for deducing information on bird migration offers a great opportunity for a European‐wide monitoring network of bird migration.  相似文献   
70.
This study examined the relationship of muscular and skeletal scores and ultrasound measurements in the live animal, and carcass conformation and fat scores with carcass composition and value using 336 steers, slaughtered at 2 years of age. Live animal scores and measurements were recorded at 8 to 12 months of age and pre-slaughter. Following slaughter, each carcass was classified for conformation and fatness and the right side dissected into meat, fat and bone. Carcass conformation scores and fat scores were both measured on a continuous 15-point scale and ranged from 2.0 to 12.0 and from 2.8 to 13.3, respectively. Pre-slaughter muscular scores showed positive correlations (P < 0.001) ranging from 0.31 to 0.86 with carcass meat proportion, proportion of high-value cuts in the carcass, conformation score and carcass value, significant negative correlations with carcass fat (r = -0.13) and bone (r = -0.81) proportions, and generally low non-significant relationships with the proportion of high-value cuts in meat and carcass fat score. Pre-slaughter ultrasound muscle depth and carcass conformation score showed similar correlations with carcass traits to those using the pre-slaughter muscular scoring procedure. Pre-slaughter ultrasound fat depth showed positive correlations (P < 0.001) with carcass fat proportion (r = 0.59) and fat score (r = 0.63), and significant negative correlations (-0.23 to -0.50) with carcass meat and bone proportions, high-value cuts in the carcass and in meat, and carcass value. Pre-slaughter skeletal scores generally showed poor correlations ranging from -0.38 to 0.52 with the various carcass traits. Corresponding correlations (-0.26 to 0.44) involving records collected at 8 to 12 months of age were lower than those using pre-slaughter records. A one-unit increase in carcass conformation score increased carcass meat proportion and value by 11.2 g/kg and 5.6 cents/kg, respectively. Corresponding values for fat score were -8.2 g/kg and -5.1 cents/kg. In conclusion, both pre-slaughter live animal scores/measurements and carcass classification scores, explained an appreciable amount of the total variation in carcass meat, fat and bone proportions and carcass value, and a moderate amount of the variation in proportion of high-value meat cuts in the carcass.  相似文献   
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