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681.
目的:在兔固定的膝关节内定期注入透明质酸钠,观察关节内外组织的变化。方法:实验于2003-10/2004-04在大连医科大学完成。实验分组:新西兰兔24只,随机分为透明质酸钠组、生理盐水组、单纯对照组,每组8只。实验干预:用树脂绷带将兔右膝关节固定于伸直位,膝关节注射部位开窗,左膝自由活动(自身对照侧)。透明质酸钠组膝关节腔内注入透明质酸钠0.1mL,生理盐水组注射同等剂量的生理盐水,单纯对照组不向关节内注射任何药物,每周1次,共5次。实验评估:5周后麻醉下处死动物,去除外固定,采用改良Clarke-Weeknesser关节伸屈范围检查标准测量右膝关节的活动范围;采用改良的Rydell-Balazes肉眼粘连评分标准评估膝关节内纤维粘连情况;光镜下观察股间肌、股直肌、髌内外侧支持带的纤维变性情况。结果:动物饲养过程中死亡4只,进入结果分析透明质酸钠组7只,生理盐水组6只,单纯对照组7只。①右膝关节的活动范围:透明质酸钠组大于生理盐水组和单纯对照组[(37.86±2.94)°,(15.67±2.23)°,(14.29±1.96)°,P<0.01]。②膝关节内纤维粘连评分:透明质酸钠组小于生理盐水组和单纯对照组(1.44±0.49,3.33±0.44,3.44±0.57,P<0.01)。③光镜下透明质酸钠组股间肌、股直肌的纤维变性较生理盐水组和单纯对照组减轻,髌内外侧支持带胶原纤维成分的变化也减轻。结论:在固定的兔膝关节内注射透明质酸钠不但可以明显抑制关节内的纤维性粘连;还可以抑制关节外股间肌、股直肌、髌内外侧支持带的组织变性。  相似文献   
682.
683.
The in vitro activity of difloxacin (A-56619) and A-56620, two new aryl-difluoroquinolones, was decreased by magnesium at 9 mM and in assay at pH 5.5 or in urine. Resistance was seen with members of the family Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus repeatedly exposed to subinhibitory concentrations of the compounds. The frequency of resistance was similar to that found for other new quinolones.  相似文献   
684.
Different clinical expressions of acid alpha-glucosidase deficiency have been described. The present study was undertaken to investigate the basic metabolic defect in the infantile and adult forms of the disease. Acid alpha-glucosidase (EC 3.2.1.20) was purified from normal and from adult acid alpha-glucosidase deficiency fibroblasts. The pH optimum; Michaelis constant; electrophoretic mobility in starch; thermal denaturation at pH 4.0 and 7.0; and inhibition by turanose, alpha-methylglucoside and trehalose were the same in purified enzyme from normal and mutant cells. Placental acid alpha-glucosidase was purified to, or near, homogeneity. Monospecific antibodies raised against the enzyme in each of three enzyme peaks obtained from the last purification step were found to cross-react with the enzyme of all three peaks, and with purified, normal fibroblast enzyme. Cross-reacting material (CRM) also was identified in fibroblast lysates from normal subjects and from both forms of acid alpha-glucosidase deficiency. The amount of CRM in the adult form appeared to be significantly less than in normal cells or cells from the infantile form. Enzyme activity was demonstrated in the immune complexes of the normal and adult acid alpha-glucosidase deficiency fibroblasts, but not of the infantile form. Competition for antibody binding sites was observed between normal and both types of mutant enzymes. The findings indicate that this case of infantile acid alpha-glucosidase deficiency is the result of a structural gene mutation which causes the synthesis of a catalytically inactive (CRM-positive) enzyme protein. It appears that in the adult form, the mutation causes a reduction in the amount of the enzyme protein present in the cells.  相似文献   
685.
Fixed‐dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster‐randomized trial evaluates effectiveness and safety of a treatment protocol that used two‐drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6‐month follow‐up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6‐months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster‐adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6‐months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates.  相似文献   
686.
Aims: Brain abscess is rare in children. Predisposing factors are found in almost 85% of cases. Overall, 25% of brain abscesses develop in children, mostly in the 4–7 years age group. Our study aimed to characterize children with brain abscesses treated in our hospital, identify risk factors, pathogens and short‐term outcome. Methods: A retrospective cohort of 20 years period, (1989–2009) included 27children (0–18 years). Medical records were analysed for age, gender, presenting symptoms and signs, predisposing factors, laboratory tests, imaging, microbiology results, treatment and outcome. Results: Of all the children, 63% (17/27) were male patients; mean age was 7.9 years and 52% were referred from other hospitals. Predisposing factors were identified in 81%, congenital heart disease and otitis were rare and sinusitis was found in 22% of the children. Main symptoms and signs included headaches, fever, neurological signs convulsions, (41%, 81%, 78% and 41% respectively). In 30% of cases, cultures were sterile. All patients were operated in addition to antibiotic treatment. Outcome was good with low mortality rate (3.7%). Conclusions: Manifestations of brain abscess may be subtle. A high index of suspicion and early imaging are warranted, different predisposing factors may reflect early intervention for congenital heart diseases. Mortality is rare in the modern medicine era.  相似文献   
687.
目的:观察血小板反应素4基因G29926C(A387P)多态性与中国苏皖地区汉族人群不稳定型心绞痛的可能关系。方法:选择2004-11/2006-05在南京医科大学第一附属医院和江苏大学附属武进医院住院不稳定型心绞痛患者110例,病例均符合2002年AHA/ACC关于不稳定型心绞痛诊断指南的诊断标准,同期选择337例非冠心病者为对照。酚-氯仿法提取白细胞DNA,应用聚合酶链反应-限制性片段长度多态性方法分析血小板反应素4A387P多态性,取部分PCR扩增产物进一步测序鉴定,比较两组间多态性频率分布差异,探讨血小板反应素4基因多态性与不稳定型心绞痛发病的可能关系。结果:447例均进入结果分析。GC基因型在不稳定型心绞痛组和对照组的分布无统计学差异(5.5%,7.1%,P=0.54),未检测到CC纯合子。C等位基因频率在不稳定型心绞痛组和对照组分别为2.7%,3.6%(P=0.55)。GC基因型与不稳定型心绞痛无显著性关联(OR=0.75,95%CI:0.30 ̄1.89,P=0.54)。结论:血小板反应素4基因387A→P不是中国苏皖地区汉族人群常见的多态位点,且与不稳定型心绞痛的发病无显著相关性。  相似文献   
688.
Peritoneal cystic mesothelioma is a relatively rare neoplasm, characterized by cystic lesions of various sizes on both visceral and parietal peritoneal surfaces. When located in the pelvis, a wide spectrum of cystic or multicystic lesions should be included in the differential diagnosis. From an imaging point of view, no definite differential diagnostic suggestions can be made, because reports of peritoneal cystic mesothelioma are few and consist mostly of case reports. The rarity of this disease, as well as its malignant potential, include it among the challenging differential diagnoses of pelvic/peritoneal cystic masses, especially in the case of a paraovarian cyst with identification of ovaries with non-suspect morphology. In this case, repetition of transvaginal ultrasound examination after a few weeks seems to be appropriate. When the findings persist, cystic peritoneal mesothelioma must be included in the differential diagnosis. Nevertheless, it seems that the definitive diagnosis of peritoneal cystic mesothelioma can be made only after surgery. Imaging with ultrasonography and magnetic resonance could play an important role in disease follow-up.  相似文献   
689.
The exact role of fibre-optic bronchoscopy (FOB) and CT of the chest in the diagnosis of patients presenting with haemoptysis and a normal or non-localizing chest radiograph has not been clearly defined. A study was designed to evaluate 50 patients presenting with haemoptysis and a normal or non-localizing chest radiograph using FOB and high-resolution computed tomography (HRCT). A definitive diagnosis was established in 17 (34%) patients. The aetiologies included bronchiectasis (24%), bronchial adenoma (6%), tuberculosis (2%) and bronchitis (2%). The diagnosis was made by HRCT in 15 (30%) patients, while FOB was diagnostic in five (10%) patients. The diagnosis was made by HRCT and FOB in all patients with focal airway abnormalities. Therefore, HRCT effectively delineated abnormalities of both the central and peripheral airways. It is concluded that CT should be obtained prior to FOB in all patients presenting with haemoptysis and a normal or non-localizing chest radiograph.  相似文献   
690.
Whole exome sequencing and chromosomal microarrays are two powerful technologies that have transformed the ability of researchers to search for potentially causal variants in human disease. This study combines these tools to search for causal variants in a patient found to have maternal uniparental isodisomy of chromosome 2. This subject has a complex phenotype including skeletal and renal dysplasia, immune deficiencies, growth failure, retinal degeneration and ovarian insufficiency. Eighteen non‐synonymous, rare homozygous variants were identified on chromosome 2. Additionally, five genes with compound heterozygous mutations were detected on other chromosomes that could lead to a disease phenotype independent of the uniparental disomy found in this case. Several candidate genes with potential connection to the phenotype are described but none are definitively proven to be causal. This study highlights the potential for detection of a large number of candidate genes using whole exome sequencing complicating interpretation in both the research and clinical settings. Forums must be created for publication and sharing of detailed phenotypic and genotypic reports to facilitate further biological discoveries and clinical counseling.  相似文献   
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