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101.
 目的 探讨NRP-1单克隆抗体(NRP-1 MAb)的特异性,以及不同剂量的NRP-1 MAb治疗乳腺癌裸鼠移植瘤的疗效。方法 Western blot和共聚焦免疫荧光法检测NRP-1 MAb是否识别MCF7细胞上NRP-1蛋白。将MCF7细胞接种于BALB/c裸鼠皮下建立乳腺癌细胞移植瘤模型,并进行瘤组织传代。传代的肿瘤体积生长至300~500 mm3时,随机分为对照组、NRP-1 MAb低剂量组、中剂量组和高剂量组,每组6只,给药7次。观察荷瘤裸鼠一般状况,测量瘤体大小及裸鼠体重。实验结束时剥离瘤体称重,提取组织蛋白,Western blot检测组织中VEGF蛋白和NRP-1蛋白的表达量。结果 NRP-1MAb成功识别MCF7细胞上的NRP-1蛋白;NRP-1 MAb能够有效抑制MCF7细胞裸鼠移植瘤的生长,低剂量组(1 mg/kg)抑瘤率为47.01%,中剂量组(5 mg/kg)抑瘤率为65.70%,高剂量组(10 mg/kg)抑瘤率为69.19%。。结论 NRP-1 MAb能够识别并有效结合MCF7细胞膜上的NRP-1蛋白,且可抑制MCF7细胞移植瘤的生长,NRP-1 MAb抑制移植瘤的增长可能与下调NRP-1和VEGF表达有关。  相似文献   
102.
在教学过程中潜移默化培养医学生的科研创新能力,是实践新时代医学教育改革新理念的有益探索。生物化学是医学生的重要专业基础课程之一,探讨在生物化学教学过程中通过多种教学方法培养学生对科研的兴趣,同时,结合科研新进展,开拓学生的视野,培养学生的创新思维,提高医学生科研创新能力的思路。  相似文献   
103.
Background and aimsPresence of diabetes mellitus (DM) during pregnancy is important cause of maternal and fetal complications. Studies that address the effect of DM on pregnancy and birth outcome are scarce in Ethiopia. The aim of this study was to determine the effect of DM on maternal and birth outcomes in Wolaita Zone, Southern Ethiopia.MethodsA retrospective cohort study was done to compare maternal and birth outcomes of mothers with DM and non-DM who received maternity service in three hospitals and four health centers in Southern Ethiopia. A total of 136 exposed (with DM) and 272 unexposed (non-DM) mothers were included in the study. Data were extracted from medical records of mothers by experienced and trained data collectors. Means were compared for continuous variables. Logistic regression analysis model was used to check the effect of DM on pregnancy and birth outcome. Risk Ratio was calculated and p value less than 0.05 was considered statistically significant.ResultsPregnancy of diabetic mothers was significantly complicated by pre-eclampsia when compared with non-diabetic mothers, (RR = 1.8: 95% CI; 1.2–2.7). The risk of macrosomia was higher for neonates of diabetic mothers than non-diabetic mothers, (RR = 1.9: 95% CI; 1.3–2.7). From multivariate analysis, mothers with DM were 2.9 times more likely to be delivered by caesarean section than non-diabetic mothers (RR = 2.9: 95%CI; 1.3–6.2) and the risk of pre-term delivery was 2.5 times higher among mothers with DM, (RR = 2.5: 95% CI; 1.1–6.2).ConclusionsDiabetes mellitus among pregnant mothers is associated with increased risk of pre-term delivery, macrosomia and maternal complications of pre-eclampsia and caesarian delivery. Early detection and management of DM should be one of the key activities to improve maternal and child mortality and morbidity.  相似文献   
104.

Background

Chronic limb-threatening ischemia (CLTI), defined as ischemic rest pain or tissue loss secondary to arterial insufficiency, is caused by multilevel arterial disease with frequent, severe infrageniculate disease. The rise in CLTI is in part the result of increasing worldwide prevalence of diabetes, renal insufficiency, and advanced aging of the population. The aim of this study was to compare a bypass-first with an endovascular-first revascularization strategy in patients with CLTI due to infrageniculate arterial disease.

Methods

We reviewed the American College of Surgeons National Surgical Quality Improvement Program targeted lower extremity revascularization database from 2012 to 2015 to identify patients with CLTI and isolated infrageniculate arterial disease who underwent primary infrageniculate bypass or endovascular intervention. We excluded patients with a history of ipsilateral revascularization and proximal interventions. The end points were major adverse limb event (MALE), major adverse cardiovascular event (MACE), amputation at 30 days, reintervention, patency, and mortality. Multivariable logistic regression was used to determine the association of a bypass-first or an endovascular-first intervention with outcomes.

Results

There were 1355 CLTI patients undergoing first-time revascularization to the infrageniculate arteries (821 endovascular-first revascularizations and 534 bypass-first revascularizations) identified. There was no significant difference in adjusted rate of 30-day MALE in the bypass-first vs endovascular-first revascularization cohort (9% vs 11.2%; odds ratio [OR], 0.73; 95% confidence interval [CI], 0.50-1.08). However, the incidence of transtibial or proximal amputation was lower in the bypass-first cohort (4.3% vs 7.4%; OR, 0.60; CI, 0.36-0.98). Patients with bypass-first revascularization had higher wound complication rates (9.7% vs 3.7%; OR, 2.75; CI, 1.71-4.42) compared with patients in the endovascular-first cohort. Compared with the endovascular-first cohort, the incidence of 30-day MACE was significantly higher in bypass-first patients (6.9% vs 2.6%; adjusted OR, 3.88; CI, 2.18-6.88), and 30-day mortality rates were 3.23% vs 1.8% (adjusted OR, 2.77; CI, 1.26-6.11). There was no difference in 30-day untreated loss of patency, reintervention of treated arterial segment, readmissions, and reoperations between the two cohorts. In subgroup analysis after exclusion of dialysis patients, there was also no significant difference in MALE or amputation between the bypass-first and endovascular-first cohorts.

Conclusions

CLTI patients with isolated infrageniculate arterial disease treated by a bypass-first approach have a significantly lower 30-day amputation. However, this benefit was not observed when dialysis patients were excluded. The bypass-first cohort had a higher incidence of MACE compared with an endovascular-first strategy. These results reaffirm the need for randomized controlled trials, such as the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-2) trial and Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI), to provide level 1 evidence for the role of endovascular-first vs bypass-first revascularization strategies in the treatment of this population of challenging patients.  相似文献   
105.
Study objectivesTo analyze the association between sleep-related symptoms and sleep length in parents and their children in relation to other risk factors in both generations.MethodThe participants were parents (n = 5,855, age 54.3 ± 6.5 years, 45.2% men) who participated in the community-based Respiratory Health in Northern Europe (RHINE) study and one random member of their adult offspring (n = 5,855, age 30.2 ± 7.7 years, 41.5% men) who participated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) study. Both generations responded to identical questionnaires on sleep symptoms, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), snoring, nocturnal sweating, nocturnal gastroesophageal reflux (nGER), sleep time and excessive daytime sleepiness (EDS). Insomnia was defined as either, or both, DIS and DMS in combination with EDS.ResultsAll sleep variables except nocturnal sweating were more common in offspring whose parents had reported the same symptom. After adjusting for age, gender, BMI, smoking, physical activity, education, center and parents' total number of children, there were independent associations between sleep symptoms in parents and offspring for DIS (adj. OR, 95% CI: 1.52, 1.20–1.93), DMS (1.34, 1.15–1.56), snoring (1.45, 1.15,1.83), nGER (1.65, 1.15–2.37), insomnia (1.39, 1.13–1.73), short sleep time (<6 h/night) (2.51, 1.72–3.68) and EDS (1.48, 1.26,1.72). There were no independent relationships between symptoms in parents and offspring for EMA, nocturnal sweating or long sleep time (>9 h/night).ConclusionThe familiar aggregation of many sleep disturbances was not explained by investigated lifestyle and environmental factors. This supports a heritable factor in sleep problems.  相似文献   
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109.
ObjectiveMultiple treatment options for acetabular fractures in geriatric patients exist. However, no large-scale studies have reported the outcomes of acute total hip arthroplasty (THA) in this patient population. We systematically evaluated all available evidence to characterize clinical outcomes, complications, and revisions of acute THA for acetabular fractures in geriatric patients.MethodsMeta-analysis of 21 studies of 430 acetabular fractures with mean follow-up of 44 months (range, 17−97 months). Two independent researchers searched and evaluated the databases of Ovid, Embase, and United States National Library of Medicine using a Boolean search string up to December 2019. Population demographics and complications, including presence of heterotopic ossification (HO), dislocation, infection, revision rate, neurological deficits, and venous thromboembolic event (VTE), were recorded and analyzed.ResultsWeighted mean Harris Hip Score was 83.3 points, and 20% of the patients had reported complications. The most common complication was HO, with a rate of 19.5%. Brooker grade III and IV HO rates were lower at 6.8%. Hip dislocation occurred at a rate of 6.1%, 4.1% of patients developed VTE, deep infection occurred in 3.8%, and neurological complications occurred in 1.9%. Although the revision rate was described in most studies, we were unable to perform a survival analysis because the time to each revision was described in only a few studies. The revision rate was 4.3%.ConclusionsAcute THA is a viable option for treatment of acetabular fracture and can result in acceptable clinical outcomes and survivorship rates in older patients but with an associated complication rate of approximately 20%. Considering the limited treatment options, THA might be a viable alternative for appropriately selected patients.  相似文献   
110.
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