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排序方式: 共有534条查询结果,搜索用时 31 毫秒
21.
目的用PCR-RFLP方法对rDNA-ITS1片段进行分析,以进一步明确云贵地区是否存在牛带绦虫亚洲亚种,并建立一种快速鉴定方法. 方法 取贵州都匀株(DY)、贵州从江株(CJ)、云南大理株(DL)带绦虫及台湾株(TW)成虫标本,剪取孕节,抽提DNA,PCR扩增rDNA- ITS1片段,分别用4种限制性内切酶MspI、CfoI、AluI、RsaI对扩增片段作酶切分析. 结果 PCR产物经AluI、RsaI酶切后, TW、DL、DY和CJ株RFLP图谱一致;经MspI、CfoI酶切后,TW、DL和DY株RFLP图谱一致,CJ株显著不同. 结论 1)DL和DY株与TW株同属牛带绦虫亚洲亚种;而CJ株是传统牛带绦虫;2)rDNA-ITS1的PCR-RFLP分析方法简便,可以用于带绦虫的分类学研究. 相似文献
22.
目的:考察相关实验室执行《中华人民共和国药典》川贝母PCR-RFLP法鉴别检验项目的技术能力,促进分子生物学技术在中药检定中的广泛应用。方法:测试样品为粉末,对样品的均匀性和稳定性进行评价,样品种类分为阳性和阴性两种,采用随机单盲方式分配至参与能力验证的实验室。各实验室按照作业指导书进行检测,并以规定格式书写原始记录。检测结果与样品性质一致的实验室为满意。对各实验室的反馈结果进行汇总和分析。结果:最终报名参加的实验室总计50家,能力验证结果为满意的26家,占52%,不满意24家,占48%。其中3家试验室未按要求返回结果,判定为不满意。分别统计不同类型参加实验室的满意率,地市级食药检机构满意率最高,为70.6%。结论:总体满意率偏低,川贝母PCR-RFLP法鉴别检验项目的整体技术水平有待提高。 相似文献
23.
M. Kishimoto Dr. M. Hashiramoto S. Araki Y. Ishida T. Kazumi F. Kanda M. Kasuga 《Diabetologia》1995,38(2):193-200
Summary We screened 214 Japanese NIDDM (non-insulin-dependent) diabetic patients with a family history of diabetes for mutations in the mitochondrial tRNALeu(UUR) gene using polymerase chain reaction-restriction fragment length polymorphism and direct sequencing. Six patients were identified as having an A to G transition at position 3243 (3243 mutation), but no patients were detected with a T to C transition at position 3271, in the mitochondrial tRNALeu(UUR) gene. These two mutations were not present in 85 healthy control subjects. It was disclosed that the patients' mothers were also affected by diabetes mellitus in five of the six cases. In these six affected patients, the 3243 mutation shows variable phenotypes, such as the degree of multiple organ involvement, intrafamilial and interfamilial differences in disease characteristics, and the degree of the involvement of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) phenotype. Endocrinological examinations revealed that those diabetic patients with the 3243 mutation show not only beta-cell dysfunction, but also a defect in alpha-cell function, which is considered characteristic of diabetes with the 3243 mutation. When compared with 50 selected diabetic control subjects without the 3243 mutation, whose mothers, but not fathers, were found to have diabetes, it was established statistically that those with the 3243 mutation possess the following clinical characteristics; 1) the age of diabetes onset is lower, 2) they have lean body constitutions, and 3) they are more likely to be treated with insulin than control subjects. We suggest that diabetes with the 3243 mutation possesses phenotypes distinct from those in common forms of diabetes.Abbreviations NIDDM
non-insulin-dependent diabetes mellitus
- IDDM
insulin-dependent diabetes mellitus
- MELAS
mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes
- PCR
polymerase chain reaction
- RFLP
restriction fragment length polymorphism
- BMI
body mass index
- ICA
islet cell antibody
- ICSA
islet cell surface antibody
- GAD
glutamic acid decarboxylase 相似文献
24.
25.
《Archivos de la Sociedad Espa?ola de Oftalmología》2020,95(9):439-446
BackgroundKeratoconus is a progressive disorder distinguished by thinning of the corneal tissue and bulging forward into a cone-shaped fashion. Yet its etiology, which is multifactorial, despite intensive research remains elusive. Corneal exposure a reactive oxygen species causing oxidative DNA damage has been reported to be associated with KC and therefore suggesting that DNA base excision repair mechanism might lie behind the pathogenesis of the disease.MethodsWe studied the association of three variants in two BER genes (XRCC1 and POLG) and QC occurrence in a cohort of patients from Egypt. Genotyping of the three variants was performed using PCR and restriction enzymes analysis.ResultsWe observed that A allele and A/A genotype of the c.1196A>G variant in the XRCC1 gene were significantly associated with increased KC occurrence while the G allele was associated with decreased KC occurrence. Similarly, the A/A genotype of the c.–1370T>A polymorphism in the POLG gene and the A allele were associated with increased occurrence of KC, while T/A genotype and the T allele were accompanied with decreased occurrence of KC. On the other hand, no association was observed between the c.580C>T variant in the XRCC1 gene and KC occurrence among the studied group of patients.ConclusionOur results suggest that c.1196A>G variant of the XRCC1 and c.–1370T>A variant of the POLG gene may be involved in KC pathogenesis and might be considered as a genetic risk factors of the disease among Egyptian population. 相似文献
26.
Khosro HAZRATI TAPPEH Gholamreza MANAFI Mohammad ASGHARZADEH Farideh MANAFI 《Iranian Journal of Parasitology》2014,9(4):541-547
Background
Giardia lamblia is one of the most prevalent intestinal flagellate protozoa that infects a wide range of vertebrate hosts causing severe intestinal disorder in children.This study was performed to determine subspecies of G.lamblia by the PCR-RFLP method, targeting the glutamate dehydrogenase(gdh)locus, in hospitalized children at Urmia Mutahhari Hospital, West Azerbaijan Province,Iran and determining the infection transformational storages in this area.Methods
Overall, 720 stool specimens were collected from the hospitalized children, 34 samples were positive and Giardia cysts were detected under the microscope. Cysts were partially purified by the sucrose density gradient method and then washed with sterile distilled water to remove effectively the PCR inhibitors. Genomic DNA of G. lamblia isolates was extracted by freeze-thaw cycles followed by phenol/ chloroform/isoamyl alcohol method. The single step PCR-RFLP assay was used to differentiate the assemblages between A and B, which were found in humans. In this method, 432 bp expected size was amplified, and then for detection of subspecies, specific restriction RsaI and BspLI enzymes were used.Results
Totally 34 samples were positive in terms of Giardia cyst out of 720 examined samples microscopically, so the parasite spread rate is reported 4.72%. Analysis PCR-RFLP on these samples revealed that 28 samples (93.3%) have the genotype BIII and 2 samples (6.7%) belong to the subgroup BIV.Conclusion
PCR-RFLP is a proper analytical method for determining the genotype among parasite types, using the glutamate dehydrogenizes zone’s genes. Based on the results, an animal origin of infection cycle is suggested. 相似文献27.
Mahmoud MAHAMI OSKOUEI Esmaeil FALLAH Mahmoud AHMADI Abdolrasoul SAFAIYAN Salar BAKHTIYARI Razi NASERIFAR Majid DOUSTI 《Iranian Journal of Parasitology》2014,9(3):435-440
Background
Cryptosporidiosis is one of the most important parasitic infections in human and animals. This study was designed for survey on the prevalence of Cryptosporidium infection in farms of Ilam, west of Iran, using parasitology method and genotyping by Nested PCR-RFLP.Methods
Fecal samples of 217 cattle were collected fresh and directly from the rectum of cattle. All of the samples were examined by microscopic observation after staining with modified Ziehl-Neelsen (MZN). Genomic DNA extracted by using EURx DNA kit. A Nested PCR-RFLP protocol amplifying 825 bp fragment of 18s rRNA gene conducted to differentiate species and genotyping of the isolates using SspI and VspI as restriction enzymes.Results
The prevalence of Cryptosporidium infection in cattle using both methods is 3.68%. Most of the positive cattle were calves under six months. Species diagnosis carried out by digesting the secondary PCR product with SspI that C. parvum generated 3 visible bands of 448, 247 and 106 bp and digested by VspI restriction enzyme generated 2 visible bands of 628 and 104bp. In this investigation all of the positive samples were Cryptosporidium parvum.Conclusion
C. parvum (bovine genotype) detected in all positive cattle samples in Ilam, west of Iran. The results of the present study can help for public health care systems to prevention and management of cryptosporidiosis in cattle and the assessment of cattle cryptosporidiosis as a reservoir for the human infection. 相似文献28.
Seyedeh Missagh JALALI Zohreh KHAKI Bahram KAZEMI Sadegh RAHBARI Parviz SHAYAN Mojgan BANDEHPOUR Seyedeh Parastoo YASINI 《Iranian Journal of Parasitology》2014,9(1):99-106
Background
The present study was carried out to investigate the accurate status of ovine Theileria infection in sheep from Ahvaz and surrounding region, a tropical area southwest Iran.Methods
A PCR-RFLP method based on 18S ribosomal RNA gene was designed which could detect and differentiate Theileria and Babesia spp. and also differentiate main Theileria species in sheep at the same time. 119 sheep blood samples were collected from Ahvaz and surroundings.Results
Microscopic examination of blood smears revealed 69.7% (83/119) infection with Theileria spp. Of the total samples subjected to PCR, 89% (106/119) were found to be positive, all of which were identified as Theileria by RFLP analysis using enzyme Hind II. In enzymatic digestion of PCR products by Vsp I, 91.5% (97/106) of Theileria positive samples were identified as T. ovis while mixed Theileria infections were found in 9 samples. The samples with mixed infections were analyzed with an additional nested PCR-RFLP method, by HpaII enzyme digestion. 3 samples with T. lestoquardi infection, 1 sample with T. ovis and T. annulata, 1 sample with T. lestoquardi and T. annulata, and 4 samples with T. ovis, T. lestoquardi and T. annulata mixed infections were detected.Conclusion
Ovine theileriosis caused by T. ovis is highly prevalent in southwest Iran while T. lestoquardi and T. annulata infection can be detected in a lesser propor-tion of sheep in this region. The new PCR-RFLP method that was designed in this study, can serve as a beneficial diagnostic tool, especially in T. ovis prevalent re-gions. 相似文献29.
《Hematology/oncology and stem cell therapy》2021,14(3):231-239
Objective/backgroundB-cell neoplasms are clonal tumors of B cells at various stages of maturation, including diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic lymphoma (CLL), Burkitt lymphoma (BL), lymphoplasmacytic lymphoma (LPL)/Waldenström’s macroglobulinemia (WM), splenic marginal zone lymphoma (SMZL), nodal marginal zone lymphoma (NMZL), mantle cell lymphoma (MCL), follicular lymphoma (FL), and hairy cell leukemia (HCL). In this study, we analyzed the frequency of MYD88 L265P mutation and its correlation with clinico-hematological profile in mature B-cell neoplasms.MethodsA total of 110 consecutive cases of B-cell neoplasms showing peripheral blood and/or bone marrow infiltration were included. MYD88 L265P mutation was detected by polymerase chain reaction amplification of exon 5 of MYD88 gene, followed by restriction fragment length polymorphism analysis.ResultsAmong the 110 cases, the major group was of CLL (54.5%, n = 60), followed by HCL. Other cases included MCL, LPL, DLBCL, SMZL, NMZL, FL, and BL. MYD88 L265P mutation was seen in 21 (19.1%) cases of B-cell neoplasm, whereas 89 (80.9%) cases were negative for MYD88 L265P mutation. It was most commonly seen in LPL/WM cases followed by HCL, SMZL, CLL, and MCL cases. No case of DLBCL, FL, and BL showed MYD88 L265P mutation. Statistically significant difference was seen for hemoglobin level in CLL cases, with MYD88 L265P mutated cases showing higher mean hemoglobin levels than MYD88 wild-type cases (p = .001). For other parameters, no statistically significant difference was noted between mutated and unmutated cases.ConclusionMYD88 L265P mutation is seen in various B-cell neoplasms; it is most commonly seen in LPL/WM cases but not specific for it. 相似文献
30.