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121.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients. 相似文献
122.
Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency 总被引:1,自引:0,他引:1
Hong YS; Kerr DS; Craigen WJ; Tan J; Pan Y; Lusk M; Patel MS 《Human molecular genetics》1996,5(12):1925-1930
An infant girl with elevated blood lactate, pyruvate, and plasma
branched-chain amino acids was diagnosed with dihydrolipoamide
dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4)
deficiency. Activities of the pyruvate dehydrogenase complex and E3 from
patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in
cultured skin fibroblasts, respectively. Western blot analysis demonstrated
that the amount of E3 protein in fibroblasts from the patient and her
father was about half of controls, while Northern blot analysis showed
normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs
from the patient revealed two mutations in separate alleles. One is a
single base insertion of an extra adenine in the last codon of the leader
peptide sequence (TAC-->TAAC) leading to a nonsense mutation which
results in the premature termination of the precursor E3 polypeptide
(Y35X). The other is a missense mutation due to substitution of guanine for
adenine, causing an Arg-->Gly substitution at amino acid 460 of the
mature protein (R460G) which triggers the loss of E3 activity probably by
structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the
parents demonstrated that the nonsense mutation was inherited from the
father and the missense mutation was inherited from the mother.
相似文献
123.
Nina Yao Jennifer Turner Zvi Kelman P. Todd Stukenberg Frank Dean David Shechter Zhen-Qiang Pan Jerard Hurwitz Mike O'Donnell 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(1):101-113
Background: The high speed and processivity of replicative DNA polymerases reside in a processivity factor which has been shown to be a ring-shaped protein. This protein (‘sliding clamp’) encircles DNA and tethers the catalytic unit to the template. Although in eukaryotic, prokaryotic and bacteriophage-T4 systems, the processivity factors are ring-shaped, they assume different oligomeric states. The Escherichia coli clamp (the β subunit) is active as a dimer while the eukaryotic and T4 phage clamps (PCNA and gp45, respectively) are active as trimers. The clamp can not assemble itself on DNA. Instead, a protein complex known as a clamp loader utilizes ATP to assemble the ring around the primer-template. This study compares properties of the human PCNA clamp with those of E. coli and T4 phage. Results: The PCNA ring is a stable trimer down to a concentration below 100 nm (Kd ≈ 21 nm ). On DNA, the PCNA clamp slides freely and dissociates from DNA slowly (t1/2 ≈ 24 min). β is more stable in solution (Kd < 60 pm ) and on DNA (t1/2 ≈ 1 h) than PCNA which may be explained by its simpler oligomeric state. The T4 gp45 clamp is a much less stable trimer than PCNA (Kd ≈ 250 nm ) and requires association with the polymerase to stabilize it on DNA as observed previously. The consequence of this cooperation between clamp and polymerase is that upon finishing a template and dissociation of the polymerase from DNA, the gp45 clamp spontaneously dissociates from DNA without assistance. However, the greater stability of the PCNA and β clamps on DNA necessitates an active process for their removal. The clamp loaders (RF-C and γ complex) were also capable of unloading their respective clamps from DNA in the presence of ATP. Conclusions: The stability of the different clamps in solution correlates with their stability on DNA. Thus, the low stability of the T4 clamp explains the inability to isolate gp45 on DNA. The stability of the PCNA and β clamps predicts they will require an unloading factor to recycle them on and off DNA during replication. The clamp loaders of PCNA and β double as clamp unloaders presumably for the purpose of clamp recycling. 相似文献
124.
125.
目的 了解酒泉市戈壁设施种植的番茄、葫芦、黄瓜、辣椒、豆角中铅、砷、汞、镉的污染状况,评估人体摄入后的健康风险。方法 利用国家标准检验方法,在酒泉市总寨和东洞戈壁农业产业园区采集检测274份主栽蔬菜中铅、砷、汞、镉含量,结合单因子污染指数和内梅罗污染指数法对蔬菜受重金属污染的程度进行评价,利用靶标污染系数法对蔬菜中重金属对人体的健康风险进行评估。结果 274份蔬菜中铅、砷、汞和镉的含量范围分别为0~0.050 1 mg/kg、0~0.053 8 mg/kg、0~0.001 0 mg/kg和0~0.048 8 mg/kg,平均含量分别为0.010 3、0.010 3、0.000 2和0.008 7 mg/kg,均未超出国家标准规定的食品中污染物限量。5种蔬菜中4种重金属的污染指数均低于0.7,靶标危害系数均小于1。结论 酒泉市总寨和东洞戈壁农业产业园区主栽的5种蔬菜受铅、砷、汞、镉污染程度较轻,属于清洁水平,处于安全级别,膳食摄入风险较低。对比其它地区蔬菜,酒泉戈壁设施蔬菜中重金属含量总体不高,与有机设施蔬菜基地结果接近。 相似文献
126.
Wang Min Huang Cheng Shen Xin Zhang Yangyi Zhang Zurong Li Jing Zhao Genming Pan Qichao Jiang Yuan 《Zeitschrift fur Gesundheitswissenschaften》2022,30(5):1055-1062
Journal of Public Health - To investigate the attack rate of active tuberculosis (TB) cases and detection rate of latent tuberculosis infection (LTBI) cases, and to identify possible factors... 相似文献
127.
Health Care Management Science - With the implementation of a series of pro-competition policies in China, the hospital market competition has been intensified dramatically over the past decade.... 相似文献
128.
Michael P. Cary Farica Zhuang Rachel Lea Draelos Wei Pan Sathya Amarasekara Brian J. Douthit Yunah Kang Cathleen S. Colón-Emeric 《Journal of the American Medical Directors Association》2021,22(2):291-296
ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively. 相似文献
129.
目的探讨基于胸痛中心急救流程在急性心肌梗死(AMI)患者救治中的应用效果。 方法选取镇江市急救中心2017年8月至2021年8月接诊的94例AMI患者为研究对象,其中男性50例,女性44例;年龄42~81岁,平均(60.37±4.31)岁。根据就诊顺序分为对照组和研究组,每组各47例,对照组患者接受常规急救流程,研究组患者接受基于胸痛中心基础上的急救流程,比较两组患者急救各环节时间、不良心血管事件发生率及患者满意度。 结果研究组患者急救各环节时间较对照组更短,两组比较差异有统计学意义(P<0.05);研究组患者不良心血管事件发生率显著低于对照组(6.38%比23.40%),两组比较差异有统计学意义(P<0.05);研究组患者满意度显著高于对照组(93.62%比78.72%),两组比较差异有统计学意义(P<0.05)。 结论基于胸痛中心急救流程可有效缩短急救过程中各环节时间,最大限度降低不良心血管事件发生风险,患者满意度高,对提高AMI患者救治效果、改善预后具有积极意义。 相似文献
130.
瘦素受体Gln223Arg基因多态性与不同葡萄糖耐量血清瘦素的相关性研究 总被引:2,自引:0,他引:2
目的 :研究瘦素受体基因Gln2 2 3Arg等位基因与不同葡萄糖耐量中血清瘦素及其它代谢指标的关系。方法 :运用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法测定无亲缘关系 ,不同葡萄糖耐量 198例北京地区汉族人的瘦素受体基因Gln2 2 3Arg等位基因 ,同时分析其与临床资料的相关性。结果 :不同等位基因型的瘦素水平无显著差异 ,而在葡萄糖耐量减低 (IGT)男性 ,Gln2 2 3Arg等位基因有较高的胆固醇水平 [(7 2 6±1 95 )和 (5 31± 1 31)mmol/L ,P =0 0 4]和较高的收缩压 [(18 8± 1 2 )和 (17 2± 1 6 )kPa ,P =0 0 3]。结论 :瘦素受体Gln2 2 3Arg基因多态性与不同葡萄糖耐量的血清瘦素无关 ,但与机体代谢有一定关系 相似文献