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101.
丹参种子形态结构与吸水萌发特性   总被引:6,自引:1,他引:6  
目的 :系统研究丹参种子的形态结构与吸水萌发特性 ,为丹参规范化栽培提供理论依据和技术参考。方法 :形态结构研究采用扫描电子显微镜观察并拍照 ;种子吸水 /脱水速率用重量法 ,种子发芽条件研究参照国家农作物种子检验规程和国际标准的有关规定进行。结果 :①通过种子形态结构观察发现 ,在丹参果实的果皮外层有 10~20μm厚度的黏液物质覆盖 ,并形成菱形网纹结构 ,其重量占种子重量的 8%~ 10 % ;②黏液物质能够迅速吸水膨胀 ,2h吸水量可达种子原重的 10倍以上 ,而脱水速率却远低于吸水 ;③丹参种子发芽的最适温度在 25℃左右 ,当年的新种子发芽率可以达到 75%以上 ,在 23℃ ,28℃变温条件下发芽势与活力指数最高。同时发现 ,预先冷冻、PEG引发和GA3 浸种等处理技术可以明显提高丹参种子的发芽率。  相似文献   
102.
岳甫嘉诊病重视脉症合参,尤以诊脉见长;处方多用中和之剂,收固真阴,反对过用热药,耗散精血。诊治思维贯穿其著作《妙一斋医学正印种子编》上卷所载验案。此卷专门论述男性不育的诊治,虽仅载验案八则,但八者皆奇,诊治结合,涵盖多法,可归纳为“先清热毒,再施温补”“药用滑涩,当辨标本”“先治脾,后治肾”“脾肾同治”“先祛痰火,再滋肾阴”及“交通心肾”6类,诸法之中的诊治思维,蕴含奥妙,颇具特色,特作探析。  相似文献   
103.
Abstract

A highly specific and sensitive competitive radioimmunoassay was developed for caerulein (CLN), an analogue of cholecystokinin-8 (CCK-8), in plasma and brain. Antiserum was produced in rabbit by immunization with Nδ-[CLN-(1-6)]-ornithine amide conjugated with bovine serum albumin by the glutaraldehyde method. Nα-[CLN-(1-6)]-lysine amide was labelled with 125I-Bolton & Hunter reagent and used as a labelled antigen after purification by high-performance liquid chromerography. This assay was highly specific for CLN, and cross reactivities for other related peptides, CCK-4, CCK-8, gastrin-I, and gastrin-(14–17), were not observed (<0.01%). The limits of determination in biological specimens after CLN administration were 11 pg/ml in human plasma and rat plasma and 80 pg/g in rat brain. This study showed that the slight structure difference between hapten and 125I-labelled antigen is important to the assay performance.  相似文献   
104.
目的 探讨子宫内膜芳香化酶联合血清CA125检测对卵巢子宫内膜异位症(EMs)的诊断价值.方法 经腹腔镜或开腹手术证实为卵巢子宫内膜异位囊肿的患者42例为实验组,同期因宫颈上皮内瘤变(CIN)行子宫全切术的卵巢正常患者30例为对照组.术前检测两组血清CA125水平,术后检测实验组在位及异位子宫内膜和对照组子宫内膜芳香化酶的表达.结果 实验组血清CA125水平高于对照组,差异有统计学意义(P<0.05);芳香化酶在实验组异位及在位内膜均有强表达,对照组子宫内膜无表达或弱表达,差异有统计学意义(P<0.05).单独检测在位子宫内膜芳香化酶诊断EMs的敏感性为73.8%,特异性为90.0%,诊断正确率为80.6%;单独血清CA125测定诊断EMs的敏感性为66.7%,特异性为90.0%,诊断正确率为76.4%.在位内膜芳香化酶联合血清CA125检测诊断EMs的敏感性为92.9%,特异性为83.3%,诊断正确率为88.9%.结论 在位子宫内膜芳香化酶检测对EMs诊断具有一定价值,与血清CA125联合检测对EMs更具早期诊断价值.  相似文献   
105.
There is an increasing need for the identification of novel biological markers and potential therapeutic targets in epithelial ovarian cancer (EOC). Given the critical role of growth factors in the biology of EOC, we aimed in the present study to evaluate the intratumoral expressions of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) proteins and their clinical relevance in a cohort of 100 patients with EOC. All patients received platinum-based chemotherapy after surgery. A comparative immunohistochemical study of normal ovarian and EOC tissues showed that both growth factors were expressed at higher levels in tumor samples. In our statistical analysis, while no association existed between the FGF expression status and the clinicopathological characteristics of patients, intratumoral VEGF was identified as a potential biomarker for the prediction of ascites formation. In addition, the expression status of VEGF appeared to independently predict overall survival and response to chemotherapy. Furthermore, a direct association was demonstrated between the pre-treatment VEGF expression and serum CA125 after three cycles of chemotherapy. In sum, we report for the first time to our knowledge the correlation between intratumoral VEGF and serum CA125 in EOC. Our data also shows the prognostic value of VEGF expression in EOC. These results suggest the potential value of intratumoral VEGF in patient stratification. Dual inhibition of VEGF and CA125 might bring about a better outcome for patients with EOC.  相似文献   
106.
Abstract

Purpose: Triplex-forming oligonucleotides (TFO) bind to the DNA double helix in a sequence-specific manner. Therefore, TFO seem to be a suitable carrier for Auger electron emitters to damage exclusively targeted DNA sequences, e.g., in tumor cells. We studied the influence of I-125 labeled TFO with regard to cell survival and induction of DNA double-strand breaks (DSB) using TFO with different genomic targets and target numbers. Furthermore, the ability of TFO to alter the gene expression of targeted genes was examined.

Materials and methods: TFO were labeled with I-125 using the primer extension method. DNA triplex formation and sequence-specific DSB were demonstrated in vitro. Cell survival was analyzed by colony-forming assay and DNA damage was assessed by microscopic quantification of protein 53 binding protein 1 (53BP1) foci in the human squamous carcinoma cell line II (SCL-II). Quantitative real-time polymerase-chain-reaction (qRT-PCR) was performed to analyze gene expression alterations.

Results: The sequence-specific induction of a single DSB in a 1695 bp long DNA double stranded fragment was demonstrated in vitro. I-125-labeled TFO binding to single and multiple targets were shown to induce a pronounced decrease in cell survival and an increase of DSB. TFO targeting multiple sites differing in the total target number showed a significant different cell killing per decay that is also in good accordance with the observed induction of DSB. Single gene targeting I-125-labeled TFO significantly decreased cell survival and altered gene expression in the targeted gene.

Conclusions: I-125-labeled TFO enable specific targeting of DNA in vitro as well as in a cellular environment and thus induce sequence-specific complex DNA lesions. Therefore I-125-labeled TFO might be a very useful tool for basic DNA repair research.  相似文献   
107.
We treated patients under age 50 years with iodine-131 (131I)–anti-CD45 antibody combined with fludarabine and 2 Gy total body irradiation to create an improved hematopoietic cell transplantation (HCT) strategy for advanced acute myeloid leukemia or high-risk myelodysplastic syndrome patients. Fifteen patients received 332 to 1561 mCi of 131I, delivering an average of 27 Gy to bone marrow, 84 Gy to spleen, and 21 Gy to liver. Although a maximum dose of 28 Gy was delivered to the liver, no dose-limiting toxicity was observed. Marrow doses were arbitrarily capped at 43 Gy to avoid radiation-induced stromal damage; however, no graft failure or evidence of stromal damage was observed. Twelve patients (80%) developed grade II graft-versus-host disease (GVHD), 1 patient developed grade III GVHD, and no patients developed grade IV GVHD during the first 100 days after HCT. Of the 12 patients with chronic GVHD data, 10 developed chronic GVHD, generally involving the skin and mouth. Six patients (40%) are surviving after a median of 5.0 years (range, 4.2 to 8.3 years). The estimated survival at 1 year was 73% among the 15 treated patients. Eight patients relapsed, 7 of whom subsequently died. The median time to relapse among these 8 patients was 54 days (range, 26 to 1364 days). No cases of nonrelapse mortality were observed in the first year after transplantation. However, 2 patients died in remission from complications of chronic GVHD and cardiomyopathy, at 18 months and 14 months after transplantation, respectively. This study suggests that patients may tolerate myeloablative doses >28 Gy delivered to the liver using 131I-anti-CD45 antibody in addition to standard reduced-intensity conditioning. Moreover, the arbitrary limit of 43 Gy to the marrow may be unnecessarily conservative, and continued escalation of targeted radioimmunotherapy doses may be feasible to further reduce relapse.  相似文献   
108.
目的:研究外源NO对刺五加种子解除休眠及萌发过程中内源激素及酶的变化规律,为打破刺五加种子休眠和人工栽培提供依据。方法:考察不同浓度(1,5,10,20 mmol·L~(-1))的外源NO供体硝普钠(SNP)处理刺五加种子,而后进行变温层积处理。采用高效液相色谱法检测出在不同层积时间(0,30,50,80,100,130 d)的内源激素赤霉素(GA3),脱落酸(ABA),吲哚乙酸(IAA),吲哚丁酸(IBA)及水杨酸(SA)含量变化。采用酶标仪全程监测体内酶[过氧化氢酶(CAT),超氧化物歧化酶(SOD),过氧化物酶(POD),丙二醛(MDA)]水平的变化。结果:在刺五加种子萌发过程中,GA3,IAA,IBA和SA的含量逐渐增大,脱落酸的含量逐渐减小。POD和MDA水平显著下降,CAT和SOD的酶活力显著上升。外源NO可以提高刺五加种子萌发率,缩短种子萌发时间,20 mmol·L~(-1)SNP促进种子萌发效果最为明显,10 mmol·L~(-1)SNP促进种子萌发效果最弱,呈"V"型变化。结论:SNP促进刺五加种子萌发可能通过提高种子萌发过程中的激素和酶的含量,以提高种子内源NO含量而实现。  相似文献   
109.
Purpose: Certain guanine-rich DNA sequences have the capacity to fold into four-stranded structures stabilized by the stacking of square planar arrangements of four hydrogen-bonded guanine bases. However both the overall topology of folding and the more detailed three dimensional structure of these quadruplexes is difficult to determine or predict, and they can be polymorphic, altering radically depending on environmental conditions. Radioprobing experiments, in which Auger electrons emitted during the decay of a 125I-containing base induce strand cleavage in a distance- and structure-dependent manner, have provided possible means of determining these details. Here we have used a combination of computer simulation methods to study the information obtained by one such experiment, reported in 2004.

Method: Models were constructed of three quadruplex topologies considered in the experiment, and one other topology proposed more recently. Molecular Dynamics simulations were used to equilibrate these structures and monitor how they evolved over several nanoseconds in solution. Snapshots from the trajectories were then subjected to Monte Carlo track structure prediction, from which theoretical cleavage patterns have been extracted.

Results: The four topologies were found to yield quite different cleavage patterns, which allow the presence of particular conformations in an experiment to be predicted.

Conclusion: Radioprobing, which is usable in biologically relevant environments, is sensitive enough to distinguish with some confidence between alternative folding topologies in a DNA structure. Monte Carlo track structure simulation can reinforce or question conclusions drawn from experiment, and Molecular Dynamics used with various restraints provides a practical means of guiding a model towards one that yields cleavage patterns closer to those found experimentally.  相似文献   
110.
蒋慧云  黄珊瑜  李小毛 《新医学》2021,52(7):541-544
目的 探究卵巢畸胎瘤患者中发生抗N-甲基-D-天冬氨酸受体(NMDAR)脑炎的比例,并将合并抗NMDAR脑炎的卵巢畸胎瘤患者与未合并抗NMDAR脑炎的卵巢畸胎瘤患者的临床特征进行总结对比。方法 收集卵巢畸胎瘤患者的临床资料,将其分为合并抗NMDAR脑炎组与未合并抗NMDAR脑炎组,对其临床特征进行对比分析。结果 共收集到168例卵巢畸胎瘤患者,其中14例(8.3%)合并抗NMDAR脑炎;合并抗NMDAR脑炎的卵巢畸胎瘤患者年龄低于未合并抗NMDAR脑炎的卵巢畸胎瘤患者[(23.8±5.5)岁 vs. (29.8±9.1)岁,P = 0.016]。合并抗NMDAR脑炎的卵巢畸胎瘤患者肿瘤标志物以癌抗原125及血清铁蛋白升高为主,而未合并抗NMDAR脑炎的卵巢畸胎瘤患者肿瘤标志物以糖类抗原199升高为主。合并抗NMDAR脑炎与未合并抗NMDAR脑炎的卵巢畸胎瘤患者的肿瘤组织均可含有神经组织。结论 卵巢畸胎瘤患者中发生抗NDMAR脑炎的比例不低,对于无明显症状的卵巢畸胎瘤患者,可考虑积极行手术治疗,以降低发生抗NMDAR脑炎的风险。  相似文献   
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