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排序方式: 共有1103条查询结果,搜索用时 62 毫秒
101.
The effect of sterilization on transforming growth factor beta isolated from demineralized human bone 总被引:1,自引:0,他引:1
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation. 相似文献
102.
目的:观察碱性成纤维细胞生长因子对大鼠脑出血后出血灶周围脑组织和出血侧海马bax、bcl-2基因表达的影响,探讨神经营养因子对神经细胞调亡的调控。方法:实验于2006-01/10在广西医科大学医学科学实验中心完成。①取成年清洁级Wistar大鼠72只,雌雄各半,体质量250g左右。②采用脑内囊注射胶原酶建立大鼠脑出血模型,动物于苏醒后按Bederson法进行神经病学评分,评分>3分后入选本实验,入选72只大鼠随机抽签法分为3组,每组24只。碱性成纤维细胞生长因子组按8μg/kg剂量肌肉注射,1次/d;生理盐水组肌肉注射等剂量的生理盐水,1次/d;模型组不作任何干预。③每组分别于干预后1,3,7d随机抽取8只大鼠,麻醉状态下取出血灶周围脑组织和出血侧海马,采用半定量反转录-聚合酶链反应检测调亡调控基因bax mRNA,bcl-2mRNA的表达。结果:在建立脑出血模型中共5只大鼠死亡,随后对死亡动物进行解剖,发现脑内血肿量过大,致脑疝形成而导致死亡,后随机补充动物。72只大鼠进入结果分析。①血肿周围脑组织bax mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组血肿周围脑组织bax mRNA表达比生理盐水组明显减少(3d:0.54±0.19,0.76±0.23,P<0.05;7d:0.45±0.19,0.71±0.16,P<0.01)。②血肿周围脑组织bcl-2mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组的血肿周围脑组织bcl-2mRNA表达比生理盐水组明显增高(3d:0.68±0.25,0.39±0.19,P<0.05;7d:0.80±0.21,0.48±0.18,P<0.01)。③出血侧海马bax mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bax mRNA表达比生理盐水组均明显减少(3d:0.54±0.18,0.70±0.11;7d:0.43±0.24,0.69±0.18,P均<0.05)。④出血侧海马bcl-2mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bcl-2mRNA表达比生理盐水组均明显增多(3d:0.66±0.11,0.50±0.15;7d:0.72±0.12,0.52±0.22,P均<0.05)。结论:碱性成纤维细胞生长因子能调节凋亡相关基因,提高大鼠脑出血后大脑脑组织和海马bcl-2mRNA的表达,降低bax mRNA的表达。 相似文献
103.
Hermida JS Jarry G Tcheng E Moullart V Arlot S Rey JL Schvartz C 《Archives des maladies du coeur et des vaisseaux》2004,97(3):207-213
Amioradone-induced hyperthyroidism is a common complication of amiodarone therapy. Although definitive interruption of amiodarone is recommended because of the risks of aggravation of the arrhythmias, some patients may require the reintroduction of amiodarone several months after normalisation of thyroid function. The authors undertook a retrospective study of the effects of preventive treatment of recurrences of amiodarone-induced hyperthyroidism with I131. The indication of amiodarone therapy was recurrent, symptomatic, paroxysmal atrial fibrillation in 13 cases and ventricular tachycardia in 5 cases (M = 14, average age 64 +/- 13 years). The underlying cardiac disease was dilated cardiomyopathy (N = 5), ischaemic heart disease (N = 3), hypertensive heart disease (N = 2), arrhythmogenic right ventricular dysplasia (N = 2) or valvular heart disease (N = 2). Two patients had idiopathic atrial fibrillation. An average dose of 576 +/- 184 MBq of I131 was administered 34 +/- 37 months after an episode of amiodarone-induced hyperthyroidism. Amiodarone was reintroduced in 16 of the 18 patients after a treatment-free period of 98 +/- 262 days. Transient post-radioiodine hyperthyroidism was observed in 3 cases (17%). Sixteen patients (89%) developed hypothyroidism requiring replacement therapy with L-thyroxine. There were no recurrences of amiodarone-induced hyperthyroidism. After 24 +/- 17 months follow-up, the arrhythmias were controlled in 13 of the 16 patients (81%) who underwent the whole treatment sequence. The authors conclude that preventive treatment with I131 is an effective alternative to prevent recurrence of amiodarone-induced hyperthyroidism in patients requiring reintroduction of amiodarone to control their arrhythmias. 相似文献
104.
Kandzari DE Hasselblad V Tcheng JE Stone GW Califf RM Kastrati A Neumann FJ Brener SJ Montalescot G Kong DF Harrington RA 《American heart journal》2004,147(3):457-462
Background
Investigations of glycoprotein (GP) IIb/IIIa inhibition in primary percutaneous coronary intervention (PCI) have suggested the efficacy of abciximab in improving clinical and angiographic outcomes, but sample-size limitations and variability in trial design preclude the ability to generalize these results to a broader patient population.Methods
Meta-analytic techniques were used to evaluate clinical outcomes from randomized trials comparing GP IIb/IIIa inhibition with placebo or control therapy in primary PCI for acute myocardial infarction (MI).Results
In 3266 patients, treatment with abciximab significantly reduced the 30-day composite end point of death, reinfarction, or ischemic or urgent target-vessel revascularization (TVR; odds ratio [OR], 0.54; 95% CI, 0.40-0.72), with trends toward reduced 30-day death and death or reinfarction. Abciximab resulted in an increased likelihood of major bleeding (OR, 1.74; 95% CI, 1.11-2.72). By 6 months, abciximab significantly reduced the occurrence of death, reinfarction, or any TVR (OR, 0.80; 95% CI, 0.67-0.97), and there were positive trends favoring a decrease in mortality alone and the composite of death or reinfarction.Conclusions
Treatment with abciximab significantly reduces early adverse ischemic events, a clinical benefit that is maintained at 6-month follow-up. These findings support the use of adjunctive GP IIb/IIIa inhibition in primary PCI. 相似文献105.
Translocation breakpoints are clustered on both chromosome 8 and chromosome 21 in the t(8;21) of acute myeloid leukemia 总被引:3,自引:0,他引:3
The t(8;21)(q22;q22) is consistently associated with acute myeloid leukemia (AML) M2. Recent data have suggested that breakpoints on chromosome 21 are clustered within a single intron of a novel gene, AML1, just downstream of a region of homology to the runt gene of D melanogaster. In this report, we confirm rearrangement at the same location in at least 12 of 18 patients with t(8;21). Furthermore, we have isolated recombinant clones spanning the breakpoint regions on both the der(8) and the der(21) from one patient. By using a chromosome 8 probe derived from these clones, we show that t(8;21) breakpoints are also clustered on chromosome 8. 相似文献
106.
Corlien JH de Vries Margreet Wieringa-de Waard Patrick JE Bindels Willem M Ankum 《The British journal of general practice》2011,61(587):e340-e346
Background
Diagnostic ultrasonography is used by GPs in approximately 10% of patients of reproductive age with abnormal vaginal bleeding. Transvaginal sonography is recommended as a first-line diagnostic instrument for assessing uterine pathology.Aim
To assess if findings resulting from openaccess sonography were in agreement with the GPs’ working hypotheses and if these findings contributed to GPs’ management.Design and setting
Prospective observational cohort study of GPs working in the health district of the Academic Medical Center, Amsterdam and their patients consulting with abnormal vaginal bleeding.Method
Data on patients’ history, GPs’ primary working hypotheses, and intended management were recorded. After sonography, GPs recorded their actual management.Results
A total of 122 patients were included by 18 GPs from June 2003 to December 2004. Data from 89 patients were available for analysis. The GPs’ working hypotheses implied ‘no structural pathology’ in 65/89 patients, and ‘fibroids’ in 24/89 patients. Sonographic findings were confirmed in 50/65 patients where ‘no structural pathology’, and in 14/24 of those where ‘fibroids’ were expected. Initially, GPs had intended to refer nine patients to a gynaecologist. Actual management after sonographic assessment was watchful waiting or drug therapy in 57/89 patients. Eighty-nine per cent of these patients had normal sonographic findings. The actual referral rate rose to 27/89 patients. In 17 referred patients, sonographic findings were suggestive of intracavitary abnormalities.Conclusion
Open-access sonography contributed to more accurate diagnoses and improved GPs’ management of women with abnormal vaginal bleeding. 相似文献107.
Background
In November 2006, an email-based health promotion program for pregnant women was implemented nationally in the Netherlands. The program consisted of emails containing quizzes with pregnancy-related questions tailored to the number of weeks of pregnancy. Emails were sent out once every 4 weeks, up to a maximum of nine emails.Objectives
The aims of the study were (1) to assess the recruitment of participants and their representativeness of the Dutch population and (2) to study differences in recruitment, program use, and program appreciation among women with different levels of education.Methods
Data from 13,946 pregnant women who enrolled during the first year of the program were included. Upon registration, participants were asked how they found out about the program and subsequently received an email questionnaire to assess demographic, lifestyle, and Internet characteristics. Program use was tracked, and participants were classified into five user groups (inactive to very active). Program appreciation (low, intermediate, and high) was assessed twice with an email questionnaire that was sent after the woman had received her third and sixth quiz email. Information about pregnant women and their characteristics was obtained from Dutch registries to assess representativeness of the study population.Results
About 8% of the pregnant women in the Netherlands enrolled in the program. Immigrants were underrepresented, and women with a low level of education seemed to be slightly underrepresented. Most women knew about the program from a promotional email sent by the organization (32%), followed by the Internet (22%) and midwives (16%). Women with little education were more often inactive users of the program than were highly educated women (15% vs 11%, P < .001), whereas highly educated women were more often very active users compared with women with little education (25% vs 20%, P< .001). However, women with less education were more likely than women with more education to have a high appreciation of the program after receiving three quiz emails (52% vs 44%, P = .001).Conclusions
In this real-life setting, pregnant women can be reached through an email-based health promotion program. Selective engagement by education level remains a challenge. 相似文献108.
A-M Bisgaard M Kirchhoff JE Nielsen M Kibæk A Lund M Schwartz E Christensen 《Clinical genetics》2009,75(2):175-179
A deletion on one chromosome and a mutant allele on the other may cause an autosomal recessive disease. We report on two patients with mental retardation, dysmorphic features and low catalytic activity of arylsulfatase A. One patient had a pathogenic mutation in the arylsulfatase A gene ( ARSA ) and succumbed to metachromatic leukodystrophy (MLD). The other patient had a pseudoallele, which does not lead to MLD. The presenting clinical features and low arylsulfatase A activity were explained, in each patients, by a deletion of 22q13 and, thereby, of one allele of ARSA . 相似文献
109.
110.