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101.
链置换式扩增检测羊水中巨细胞病毒DNA 总被引:2,自引:1,他引:1
目的:介绍一种简便快速准确检测羊水中CMV-DNA的改良PCR-链置换式扩增用于诊断胎儿先天感染CMV。方法,将组成套式PCR的外内两对引物按照一定比例(外:内=1:50-100)加在同一试管中一次扩增羊水和胎儿组织中CMV-DNA。结果:90例异常孕产史的孕妇羊水检测CMV-DNA,阳性率为38.9%(35/90),其中合并染色数目异常2例(47,XYY和47,XX,+21)(已引产)核型及染色 相似文献
102.
自体造血干细胞移植治疗恶性血液病 总被引:2,自引:0,他引:2
为探讨恶性血液病的有效治疗方法,应用自体骨髓移植(ABMT)38例,自体外周血造血干细胞移植(ABSCT)13例,自体外周血造血干细胞与自体骨髓联合移植15例。治疗白血病54例,恶性淋巴瘤11例,多发性骨髓瘤1例。外周血造血干细胞采用化疗加多抗甲素或C—CSF动员。移植物采用微波、阿克拉霉素净化处理。结果:两组动员方案均有良好动员效果。ABSCT组及联合移植组造血功能恢复比ABMT组快(P<0.05),合并症少。66例中,45例仍呈持续缓解(CCR),中位CCR时间32(5~98)个月,复发21例。3年无病生存率及复发率分别为68.5%及26.1%。结果表明:自体造血干细胞移植是根治恶性血液病的有效手段。ABSCT及联合移植具有造血功能恢复快,合并症少等优点。微波和阿克拉霉素体外净化移植物是一种简便、有效的净化方法。 相似文献
103.
104.
J L Shao 《中华口腔医学杂志》1992,27(3):140-2, 189
In this paper, 220 children ranging from age 11 to 15 were selected. Each of them received a cephalometric roentgenographic examination. 153 cephalometric items from 13 types of methods which had been widely in use were studied through statistic analysis. By means of "t" test, several items which expressed little difference between the normal occlusion and the malocclusion were eliminated. By using of the cluster analysis we selected one item to represent the items which were with similar effect. Finally, 17 cephalometric items were pick out to provide references for clinical work. 相似文献
105.
A case of hyaline membrane disease was treated successfully with pulmonary surfactant (PS) isolated from human amniotic fluid. Dosage was 150 mg phospholipid/kg. The exogenous surfactant was instilled into the airway via a tracheal cannula. Clinical symptoms, PO2 and FiO2 improved evidently 24 hours after administration. L/S ratio and phosphatidylglycerol recovered gradually in aspirates. Lung X-ray film manifested "white lung" before instillation of surfactant and showed a striking improvement 3 days after treatment. The duration of mechanical ventilation was 6 days. During the period of recovery complications of patent ductus arteriosus and bacterial pneumonia developed. However, the patient recovered completely and was discharged 32 days after admission. 相似文献
106.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
107.
The kyphoscoliotic type of Ehlers-Danlos syndrome (EDS type VIA) (OMIM 225400) is an autosomal recessive connective tissue disorder that results from mutations in the lysyl hydroxylase 1 gene (PLOD1) causing underhydroxylation of lysine residues in tissue collagens, particularly of skin. Previous studies have shown that the pool of collagen cross-linking amino acids, hydroxylysyl pyridinoline (HP) and lysyl pyridinoline (LP) excreted in urine has an abnormally low HP/LP ratio, which is diagnostic of the condition. Here we isolated cross-linked peptides containing these residues from the urine of a child with EDS VIA homozygous for a mutation that results in a stop codon and effective null expression of PLOD1 enzyme activity. Peptides that had originated from bone type I collagen and cartilage type II collagen were identified. A cross-linked N-telopeptide fraction that is derived from bone type I collagen contained only LP, no HP, which means that the helical lysines at residues 930 of alpha 1(I) and 933 of alpha 2(I) of the collagen triple-helix had not been hydroxylated. The equivalent peptide fraction from a normal child's urine gave a ratio of HP to LP of 1.5:1 typical for normal bone collagen. A second cross-linked peptide that is derived from the C-telopeptide domain of cartilage type II collagen showed both HP and LP in a 2:1 ratio, compared with 18:1 for the equivalent peptide from a normal child's urine. The results show that in EDS VIA, bone type I collagen is more markedly underhydroxylated than cartilage type II collagen, at least at those helical sites that form cross-links. The residual fraction of HP found in the urine of EDS VI patients therefore appears to be contributed in significant part by the degradation products of cartilage. Since PLOD1 is null, other PLOD genes must be responsible for the helical hydroxylation activity that results in HP. The presented approach of analyzing urinary cross-linked C-telopeptide fragments of type II collagen may allow the detection of chondrodysplasias due to genetic defects in lysyl hydroxylase isoforms active in cartilage. 相似文献
108.
Association of KIR Genotypes and Haplotypes with Susceptibility to Chronic Hepatitis B Virus Infection in Chinese Han Population 总被引:1,自引:0,他引:1
Zhiming Lu Bingchang Zhang Shijun Chen Zhongtao Gai Zhaolei Feng Xiangdong Liu Yiqing Liu Xin Wen Li Li Yulian Jiao Chunyan Ma Song Shao Xiangfa Cui Guojian Chen Jianfeng Li Yueran Zhao 《Cellular & molecular immunology》2008,5(6):457-463
Killer immunoglobulin-like receptor (KIR) genes can regulate the activation of NK and T cells upon interaction with HLA class I molecules. Hepatitis B virus (HBV) infection has been regarded as a multi-factorial disorder disease. Previous studies revealed that KIRs were involved in HCV and HIV infection or clearance. The aim of this study was to explore the possibility of the inheritance of KIR genotypes and haplotypes as a candidate for susceptibility to persistent HBV infection or HBV clearance. The sequence specific primer polymerase chain reaction (SSP-PCR) was employed to identify the KIR genes and pseudogenes in 150 chronic hepatitis B (CHB) patients, 251 spontaneously recovered (SR) controls, and 412 healthy controls. The frequencies of genotype G7 M, FZ1 increased in CHB patients compared with healthy control subjects. The frequency of genotype AH was higher in SR controls than that in both CHB patients and healthy controls. The carriage frequencies of genotype G and AH were higher; while, the frequencies of AF and AJ were lower in SR controls than those in healthy control subjects. The frequency of A haplotype was lower, whereas, the frequency of B haplotype was higher in CHB patients and SR controls than those in healthy controls. In healthy controls, haplotype 4 was found lower compared with that in CHB patients and SR controls and the frequency of haplotype 5 was higher in SR controls than that in other two groups. Based on these findings, it seems that the genotypes M and FZ1 are HBV susceptive genotypes; AH, on the other hand, may be protective genotypes that facilitate the clearance of HBV. It appears that the haplotype 4 is HBV susceptive haplotype, whereas, haplotype 5 may be the protective haplotype that facilitates the clearance of HBV. Cellular & Molecular Immunology. 2008;5(6):457-463. 相似文献
109.
背景:应力遮挡效应会导致植入假体修复骨缺损手术失败,其主要原因是由于植入假体的弹性模量大于骨组织弹性模量。目的:分析植入假体弹性模量对应力分布的影响,寻求消除应力遮挡现象的方法。方法:通过CT扫描的方式获取实验犬与人体骨组织的模型,分别对其优化后进行梯度赋值,建立较为可靠的骨骼力学模型,并与植入假体组合后进行有限元仿真。首先,通过对比格犬骨骼模型和人体骨骼模型及其对应的植入假体进行有限元仿真,模拟了不同弹性模量对植入假体修复术后的应力和位移分布情况;其次,分析了较小弹性模量差仍会形成应力遮挡现象的原因,建立了骨骼模型及植入假体模型,确立了材料属性赋予方法;最后,验证了该模型及材料属性赋予方法的可行性,并通过随机选取受力点的方式,定量分析植入假体弹性模量与骨骼弹性模量之间的关系对应力遮挡形成的影响。结果与结论:通过梯度赋值法建立与骨骼力学性质更加接近的实验犬骨骼模型和人体骨骼模型,该方法重建的力学模型与真实骨骼的力学性质更为接近;通过有限元仿真力学测试证明,不同弹性模量植入假体对假体本身与周围骨骼间相对位移的影响较小;另外量化弹性模量对假体植入骨骼后对应力分布的影响,可为后续的相关研究提供帮助。 相似文献
110.
Modulation of B-cell abnormalities in lupus-prone (NZB x NZW)F1 mice by normal bone marrow-derived B-lineage cells. 下载免费PDF全文
(NZB x NZW)F1(NZB/WF1) mice spontaneously develop an autoimmune disease characterized by abnormality of haemopoietic stem cells. The present study examined a possible regulatory cell interaction between NZB/WF1 and normal bone marrow cells using radiation-induced chimeras. We demonstrated that the ability of NZB/WF1 bone marrow cells to transfer the typical disease with hypergammaglobulinemia including autoantibodies into lethally irradiated normal recipients was prevented by cotransfer of bone marrow from normal CBA/J mice but not from xid CBA/N mice carrying a selective defect in B-cell function. Flow cytometric analysis revealed that the generation of NZB/WF1 cells was reduced in the mixed chimeras given CBA/J but not CBA/N bone marrow cells. Interestingly, radiation chimeras reconstituted with a mixture of NZB/WF1 bone marrow and CBA/J splenic B cells did not show elevation of serum immunoglobulin levels, although most of the spleen cells were dominated by NZB/WF1 cells. On the other hand, NZB/WF1 B cells maturated in vivo in the presence of CBA/J bone marrow or splenic B cells lost the hyper-responsiveness to lipopolysaccharide (LPS) in the autoantibody production in vitro. These results suggest that radiosensitive normal B-lineage cells have the regulatory activity to ameliorate the hypergammaglobulinemia of NZB/WF1 mice by reducing the generation of NZB/WF1 B cells and/or by correcting their hyper-responsiveness, and that NZB/WF1 mice may have a defect(s) in the regulatory cell function. In addition, CBA/J splenic B cells were shown to modulate the B-cell abnormality even when injected into non-irradiated NZB/WF1 mice manifesting autoimmunity. 相似文献