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21.
c AMP反应成分结合蛋白 (c AMP response elem ent-binding protein,CREB)是一种转录因子 ,它在磷酸化之后可调节靶基因的转录。 CREB在 13 3位置的丝氨酸的磷酸化 ,与脊髓中伤害性传入的处理有关 ,本文作者等用特殊抗体对此进行了免疫细胞化学研究。在正常大鼠 ,虽然几乎所有脊髓神经元的核中都可见 CREB的轻度着色 ,但磷酸化的 CREB仅见于双侧腰段脊髓的 ~ 层 (75± 15 vs60± 18)和 层 (9± 3 )。用福尔马林注射引起一侧后脚掌出现炎症时 ,可在双侧腰段脊髓看到磷酸化CREB细胞核的快速 (小于 5 min)和节段性的显著增多 ;它们主要分布在双侧背角表层 ~ 层 (2 5 4± 2 0 vs 2 62± 2 3 )、 层(115± 13 )和双侧 ~ 层 (3 46± 2 0 vs3 2 8± 2 6) ;而在对照和炎症组大鼠的胸段脊髓中均未见磷酸化 CREB的增加。在注射CFA诱发一侧炎症或切断一侧坐骨神经的实验组大鼠 ,也可看到至少延续到第三天的强而双侧性的 CREB的磷酸化。这种由一侧后肢伤害性传入引致腰段脊髓中镜像式双侧 CREB磷酸化的出现 ,与一般看到的损伤传入只在同侧脊髓背角引起某些神经化学改变的结果不同 ,可能是人神经损伤后或在实验动物中出现对侧镜像式疼痛过敏现象的基础  相似文献   
22.
A complete mole coexisting with dichorionic twins was diagnosed by the combined use of sonography and chorionic villus sampling at 10 weeks gestation. The pregnancy resulted in the death of one fetus at 31 weeks from presumed feto-maternal haemorrhage, while the other fetus survived in good condition. A summary of the available literature, combined with this report, reveals a total of seven pregnancies with twins and a coexistent complete mole. Only two out of 14 fetuses survived. Maternal complications included one case of pre-eclampsia and one persistent trophoblastic tumour. Accurate diagnosis of complete mole is possible by genetic analysis of chorionic villi obtained with standard transabdominal sampling. Twins with a coexistent complete mole will usually undergo miscarriage. However, fetal survival is possible and the maternal risks seem limited. A concomitance between gestational trophoblastic disease and the occurrence of feto-maternal haemorrhage is observed.  相似文献   
23.
The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H315 L315 and F315V but not with free H315, L315, V315H or V3152. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.  相似文献   
24.
The practical realization of the concept of specific immunotherapy for systemic lupus erythematosus (SLE) has been hampered, thus far, by an inability to link DNA fragments to carrier protein. In this paper, a novel technique is described, in which glutaraldehyde is the linking agent. A 2-stage method was used to link oligonucleotides to a soluble protein carrier, such as keyhole limpet hemocyanin (KLH) or human gamma globulin (HGG), whereas a 1-stage technique was sufficient to link oligonucleotides to sheep red cells. Both the ultraviolet absorbance spectrum and diphenylamine assay demonstrated that oligonucleotides were coupled to soluble protein. The conjugate of oligonucleotide to protein carrier appears to be recognized by anti-DNA antibody since oligonucleotide linked to either KLH or HGG inhibited the binding of anti-DNA antibody in vitro, and oligonucleotide-coupled sheep cells are agglutinating by seropositve sera from lupus patients. In addition, oligonucleotide-KLH raised hemagglutinating antibody to denatured DNA in C57BL/6, DBA/2 or NZB mice, as well as IgG antibody as detected by SPRIA in C57BL/6 and DBA/2 mice. The significance of this new method for the development of an antigen specific therapy of SLE is discussed.  相似文献   
25.
We describe clinical and genetic data from the study of two families with 80 members affected with the autosomal dominant, slowly progressive spinal muscular atrophy of late onset (average 48.8 years), first described by Finkel in 1962. Electromyography and muscle biopsy of a number of patients confirmed the neurogenic nature of the condition. Unusual findings in this disorder were cramps, spontaneous fits of suffocation, and symptomatic myotonia. Other manifestations are slow loss of muscle strength and progressive proximal atrophy, which starts in the lower limbs and progresses to the upper limbs; hypoactive or absent tendinous reflexes; and generalized fasciculations. Sensory and cranial nerve function is unimpaired. Probabilities for genetic counseling are evaluated by means of a method adequate to the late-onset nature of the condition.  相似文献   
26.
目的 :通过对清洁前后的义齿表面进行细菌培养 ,了解加酶义齿清洁剂对口腔厌氧菌的杀菌效果。方法 :从临床选取 8付正在使用的全口义齿 ,随机分为两组 ,其中一组浸泡在加酶义齿清洁剂中 ,另一组不做任何处理 ,再从义齿表面取菌 ,比较细菌培养结果。结果使用加酶义齿清洁剂组经菌落计数lg均值为 0 ;未使用加酶义齿清洁剂组菌落计数lg均值为 3 .4 4。统计学结果表明 :使用加酶义齿清洁剂组与未使用加酶义齿清洁剂组相比较 ,菌落计数有极显著性差异 (P <0 .0 0 1)。结论加酶义齿清洁剂对义齿表面的口腔厌氧菌具有杀灭作用  相似文献   
27.
We aimed to investigate the association between erectile dysfunction and severity of cardiovascular morbidity and to assess clinical responses to tadalafil of patients in different cardiovascular risk groups. Between November 2019 and August 2020, a total of 258 male patients aged 45–70 years with ED were included. They were divided into three groups according to the Framingham risk score: low-risk (n: 86, 33.3%), intermediate-risk (n: 103, 39.9%) and high-risk (n: 69, 26.8%). At admission, all domains of the International Index of Erectile Function score were worse in high-risk group compared to other risk groups (p < .001). After a 12-week follow-up, a more significant improvement was observed in all domains of erectile function in all risk groups, but high-risk group had lower sexual scores (p < .001). The lowest rate for complete responsiveness to tadalafil was observed in the high-risk group (37.7%). The rate of failure in complete responsiveness was found to be 4.127 times greater with higher Framingham score and 3.102 times greater with higher erectile dysfunction severity at admission. Our preliminary findings show that more severe sexual disorders are observed in high-risk patients with cardiovascular morbidity. Individualised treatment may be important in high-risk group since they may benefit less from tadalafil, and failure in complete responsiveness can be more common in this group.  相似文献   
28.
BackgroundOver the past decade, chemotherapy has been used more selectively in early breast cancer (EBC) due to better risk stratification. Neoadjuvant chemotherapy (NACT) has evolved to the primary treatment option. The type and size of hospitals is known to have a substantial influence on the kinds of treatment they provide, and therefore on patient outcomes (e.g. rates for pathological complete response, pCR), but it is not yet known how this has affected delivery of chemotherapy for EBC in Germany.MethodsThis study analyzed chemotherapy use and pCR rates after NACT for EBC patients treated at 104 German institutions 2008–2017. Institutions were separated into associated hospital type (university hospital; teaching hospital; community hospital) and annual caseload (≤100; 101–250; >250 cases/year).ResultsOverall, 124,084 patients were included, of whom 11.6% were treated at university hospitals, 63.1% at teaching hospitals, and 25.3% at community hospitals. In total, 46,274 (37.3%) received chemotherapy, of whom 44,765 had information available about systemic treatment and surgery. From 2008 to 2017, chemotherapy use declined from 48.3% to 36.4% for university hospitals, from 40.7% to 30.3% for teaching hospitals, and from 42.4% to 33.7% for community hospitals. Furthermore, the proportion of NACT increased the most in university hospitals (from 32.0% to 68.1%); whereas, the rate of pCR (defined as ypT0 ypN0) increased irrespective of institutional type. Analyses regarding annual caseload did not show any differences.ConclusionsThe results from this large, nationwide cohort reflect a more selective use of chemotherapy in Germany, irrespective of institutional type or case load.  相似文献   
29.
张瑜  杜晨晖  詹海仙  尚彩玲  李瑞锋  原淑佳 《中草药》2023,54(15):4981-4991
目的 以桔梗Platycodon grandiflorus为材料,分析其叶绿体基因组特征,探究不同地区桔梗叶绿体基因组的差异及桔梗科其他物种的系统发育关系。方法 利用Illumina NovaSeq测序平台对桔梗叶绿体全基因组进行测序,完成其组装、注释和特征分析,采用生物信息学方法对不同地区桔梗进行比较基因组分析和系统发育分析。结果 桔梗叶绿体基因组全长172 770 bp,呈现典型的环状四分体结构,总GC含量为38.10%,注释到139个基因,其中蛋白质编码基因95个,核糖体RNA 8个和转运RNA 36个。经序列分析鉴定出139个SSR位点,大部分重复由A和T组成。该叶绿体基因组密码子偏好性A/U大于G/C。边界分析表明,不同地区桔梗的JLA边界区域存在差异。对比不同地区桔梗叶绿体基因组序列发现21个变异区间,包括ycf1psbCrps18rpoB等编码区以及rpl32-trnLtrnS-psbZtrnN-ycf1等非编码区。基于最大似然法(maximum likelihood method,ML)对桔梗及其他17种桔梗科植物进行系统发育分析,发现桔梗科物种形成一个单系群,各属物种聚为一束,支持率达100%。结论 桔梗科物种聚为一支与传统相符合,不同地区桔梗叶绿体基因组序列存在显著差异,为后期开展分子鉴定及群体遗传学研究提供提供科学依据。  相似文献   
30.
孙伟 《医用生物力学》2005,20(4):247-255
计算机辅助组织工程(CATE)可以帮助进行复杂组织支架的建模,设计和制造,使很多用于改善替代材料力学及生物学性能的新方法得以实施。CATE通过获取组织的生物学、生物力学及生物化学信息,进行界面的设计、模拟和组织的制作。本文将讲述CATE在骨组织工程支架仿生设计中的应用:介绍运用CATE进行仿生建模,解剖结构重建,组织支架设计,定量CT分析,有限元分析和支架的自由挤压沉积制作。  相似文献   
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