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11.
摘要 目的:探讨艾拉莫德对难治性类风湿关节炎患者骨密度和血清骨碱性磷酸酶(B-ALP)、I型胶原交联羧基末端肽(CTX-I)的机制。方法:选择2019年1月至2020年12月我院接诊的134例难治性类风湿关节炎患者,通过随机数表法分为观察组和对照组,每组67例。对照组给予甲氨蝶呤联合依那西普治疗,观察组给予艾拉莫德片联合依那西普治疗,均连续治疗12周。比较两组临床缓解率、实验室指标、类风湿关节炎患者病情评价(DAS28评分)、骨密度、血清B-ALP、CTX-I的变化和不良反应。结果:治疗后,观察组临床缓解率为90.00%,明显高于对照组72.50%(P<0.05);观察组红细胞沉降率(ESR)、C反应蛋白(CRP)、类风湿因子(RF)、抗环挂氨酸肽抗体(抗-CCP)表达和DAS28评分分别为(23.53±2.77)mm/h、(11.73±2.30)mg/L、(17.45±3.08)U/L、(43.22±7.17)RU/mL、(2.74±0.34)分,均明显低于对照组的(31.27±5.04)mm/h、(19.11±2.12)mg/L、(24.47±2.59)U/L、(55.23±7.44)RU/mL、(3.21±0.50)分,差异有统计学意义(P<0.05);观察组骨密度、血清B-ALP分别为(0.83±0.05)g/cm3、(117.02±15.65)U/L,均明显高于对照组(0.77±0.04)g/cm3、(101.19±9.59)U/L,观察组CTX-I为(0.36±0.04)μg/L,明显低于对照组(0.47±0.04)μg/L,差异有统计学意义(P<0.05);两组不良反应总发生率分别为4.44%和2.22%,差异无统计学意义(P>0.05)。结论:艾拉莫德联合依那西普治疗难治性类风湿关节炎效果显著,可明显改善骨密度、血清B-ALP、CTX-I的表达,提高临床缓解率,安全性好,值得应用推广。  相似文献   
12.
Characteristics of action potentials in Helianthus annuus   总被引:1,自引:0,他引:1  
The action potentials induced by nondamaging electrical stimuli in 16- to 22-day-old plants of Helianthus annuus were examined. Typical recordings are presented. Mean values of their amplitudes and conduction velocities in the stem, the strength-duration relation, the 'all-or-none' law and the refractory periods have been determined. The amplitude and velocity of propagation were essentially identical in the upward and downward direction, but greater in the upper than in the lower half. In 'electrically active' plants, the rheobase value is 2 V, the minimum period for stimulation is 1.8 s. and the chronaxie 2.3 s. It is noted that the excitability level between similar plants on the same day and in the same plant on different days is highly variable and undergoes periodic changes.  相似文献   
13.
The progress of developmental programme in the epidermal cells of last instar larvae of Bombyx mori was determined by ecdysteroid injections in normal and in JH-treated larvae. To clarify the importance of food intake in the control of development, starved animals were also used.The instar begins with a period during which the larval programme is expressed: this occurs in the presence of 20-hydroxyecdysone. Epidermal cells can thereafter secrete pupal cuticle after ecdysteroid injection although the larval programme is normally still present. During the last period only pupal characters can be expressed either in normal or in 20-hydroxyecdysone-injected larvae.These different developmental phases are not correlated with obligatory and facultative feeding periods.Transition from the first to the second phases is correlated with the absence of JH effects on pupal genes. JH applications during the second period, however, prevent the expression of pupal characters after 20-hydroxyecdysone injection. Thus, during this period, the pupal programme is not stabilized. Cellular reprogramming itself occurs at the onset of the last developmental period and is probably under the control of ecdysteroids.  相似文献   
14.
15.
雷超桂  许有鹏  张倩玉  王跃峰  李广 《生态学报》2016,36(16):5017-5026
土地利用变化对流域洪水过程产生显著影响,并导致设计洪水发生变化。为进一步指导流域防洪及水库洪水设计,以浙东沿海奉化江皎口水库流域为例,应用HEC-HMS水文模型模拟分析土地利用/覆被变化(LUCC)对不同重现期暴雨洪水事件的影响。结果表明,流域内1985—2003年土地利用变化引起不同重现期洪水过程与洪水量级发生改变,其中,洪量和洪峰均增加,洪量较洪峰变化明显。LUCC对小洪水过程影响更明显,5年一遇以上洪水的洪峰和洪量分别平均增加3%和7.6%,而小于2年一遇洪水的洪峰和洪量分别平均增加5.41%和11.91%。同时,LUCC使100年、50年和25年一遇洪水重现期分别提前了15、6a和2a,即其对量级最高的特大洪水的重现期影响最大。此外,不同的土地利用转变方式对洪水的影响程度不一,其中,林地向裸地转变对洪水影响最大,林地向灌草地转变次之,林地向耕地变化对洪水影响最小,且这种差异性在低重现期洪水表现更明显。  相似文献   
16.
Fifty-three beta-lactamase-producing strains of oral bacteria isolated from patients with refractory periodontitis in Norway and USA were screened for the presence of the bla(TEM), bla(SHV), bla(OXA), bla(ampC), bla(cfxA), and bla(cepA/cblA) genes by the polymerase chain reaction (PCR). The PCR products were characterized by direct sequencing of the amplified DNA. Thirty-four of the 53 enzyme-producing strains (64%) were positive in one of the PCR assays. All beta-lactamase-producing Prevotella and Capnocytophaga spp. were CfxA positive. TEM-type beta-lactamases were identified in one strain each of Escherichia coli and Neisseria sp., and one strain of Citrobacter freundii possessed an AmpC-type beta-lactamase. Screening for gene cassettes and genes known to be associated with integrons did not reveal the presence of integrons in these oral bacteria. Sequence analyses showed that most CfxA positive Prevotella and Capnocytophaga isolates from patients with refractory periodontitis harboured variants of the CfxA2 and CfxA3 enzyme. The present study also showed that many different genetic determinants of beta-lactamase production are found in bacteria isolated from refractory periodontitis, many of which remain to be characterized.  相似文献   
17.
Native Rhododendrons section Brachycaryx in eastern Japan are decreasing in their natural habitats and the need to restore these habitats is increasing. Conservation of genetic diversity in restoring habitat requires clarification of the balance of interspecies genetic exchange which occurs in their natural habitats. In well-preserved natural habitats of Rhododendron dilatatum, R. kiyosumense, and R. wadanum and their natural hybrids R.×kuratanum and R.×hasegawai we investigated their geographical distribution, frequency, and flowering period. DNA analysis of the internal transcribed spacer (ITS) region was also conducted to confirm the species related to hybridization. Our findings in the field survey were: (1) Hybridizations occur in the overlap zones of related species. (2) R.×hasegawai occurs more frequently than R.×kuratanum, probably because the flowering seasons of R. kiyosumense and R. wadanum overlap longer than those of R. dilatatum and R. kiyosumense. (3) Natural hybrid occurrence is, nevertheless, under 9% of all related Rhododendrons section Brachycalyx. Analysis of the ITS region suggested that the two hybrids are generated from interspecific gene exchange, i.e., (4) R. dilatatum and R. kiyosumense relate to the formation of R.×kuratanum. (5) R.×hasegawai is a hybrid of R. wadanum and some species other than R. wadanum. On the basis of these findings we delineated several guidelines for restoring habitats of Rhododendrons of Section Brachycaryx with concerns for genetic diversity: (1) Before use, identify plant materials by morphological traits to determine whether they are original species or hybrids. (2) Investigate the distribution of remnant Rhododendrons section Brachycaryx before restoration. (3) Combine plant materials of original species in the natural distribution.  相似文献   
18.
国槐尺蠖发育起点温度与有效积温   总被引:2,自引:0,他引:2  
在恒温20,23,25,27,30℃下,对沈阳市国槐尺蠖Semiothisa cinerearia Bremeret Grey各虫态的发育历期,发育起点温度和有效积温进行了研究。结果表明,随着温度的升高,发育历期逐渐缩短;国槐尺蠖卵,幼虫,蛹,成虫期和世代发育起点温度C分别为(4.20±0.95),(5.80±0.95),(8.28±0.30),(16.92±0.50)和(9.06±0.21)℃。相应的有效积温K分别为(71.3±2.3),(300.5±14.3),(354.2±8.3),(52.4±2.59)和(752.76±10.5)日.度。根据发育起点温度和有效积温,预测出国槐尺蠖在沈阳的年发生代数为3.4~3.6代,其结果符合实际发生情况。  相似文献   
19.
Caspase-8 (CASP8) plays a critical role in regulating apoptosis, and its functional polymorphisms may modify cancer risk. We investigated the possible association between CASP8 -652 6N ins/del (rs3834129) and the risk of breast cancer in a sample of Iranian population. This case-control study was done on 236 breast cancer patients and 203 cancer free healthy female. We designed a rapid and simple bi-directional PCR allele-specific amplification (bi-PASA) for detection of CASP8 -652 6N ins/del polymorphism. The results showed that the CASP8 -652 6N del/dl genotype was inversely associated with breast cancer risk (OR=0.33, 95% CI=0.17-0.65, p=0.001). The frequencies of the del allele in cases and controls were 29.1% and 38.6%, respectively. An inverse association between CASP8 6N del variant and the risk of breast cancer (OR=0.66, 95% CI=0.66-0.87, p=0.002) was found. In conclusion, the result suggests that the CASP8 -652 6N del polymorphism plays a protective role in susceptibility to breast cancer in our population. Further studies in other populations with larger samples are needed to confirm these findings.  相似文献   
20.
目的:观察雷利度胺治疗难治复发急性粒细胞白血病的疗效及不良反应。方法:给予雷利度胺单药治疗,雷利度胺50mg/d,口服给药,连续给药21天,28天为一个疗程。结果:应用雷利度胺4(2~6)个疗程,5例有效,2例获得完全缓解,2例部分缓解,1例因疾病迅速进展死亡退出试验。不良反应主要为疲乏4例,中性粒细胞减少性发热3例,中粒细胞减少4例,血小板减少1例,贫血1例。结论:应用雷利度胺治疗难治复发白血病有效,不良反应轻微且易于耐受。  相似文献   
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