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51.
个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系   总被引:2,自引:0,他引:2  
目的:分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。 方法:选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料(骨水泥、硅橡胶)组40例,根据颅骨缺损面积又分为大面积(≥36cm2)组17例和小面积(〈36cm2)组23例;覆盖性材料(钛网)组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描(层厚1.5mm),三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症:头痛、积液、松动。 结果:75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%(63/75)患者感到基本或完全恢复了原有容貌。手术并发症:嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。 结论:个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。  相似文献   
52.
Intensive sports practice seems to exert negative effects on semen parameters; in order to assess these effects, the objective of this study was to assess semen, including DNA fragmentation, and hormone parameters in elite triathletes. Twelve high‐level triathletes preparing for a National Triathlon Championship participated in the study. The qualitative sperm parameters analysed were volume, sperm count, motility, morphology and DNA fragmentation; when needed, additional testing was performed. Assessed hormones were testosterone (T), cortisol (C) and testosterone–cortisol ratio (T/C). Maximum oxygen consumption and training characteristics were also assessed. Hormonal values and physical semen parameters were within normal ranges. DNA fragmentation showed high values (20.4 ± 6.1%). Round cells in semen were higher than normal (2.8 ± 1.5 million/ml), with the presence of macrophages. Correlations were found for several parameters: concentration of round cells positively correlated with progressive sperm motility (= .01) and sperm morphology (= .02); contrarily, the correlation found with DNA fragmentation was negative (= .04). Sperm DNA fragmentation and the T/C ratio, however, were correlated in a positive manner (= .03). As evidenced by the observed results, sperm DNA fragmentation is affected by high‐level sports practice; therefore, high loads of endurance training could potentially interfere with the athlete's fertility potential.  相似文献   
53.
The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies.  相似文献   
54.
BACKGROUND AND AIM: This study was aimed to identify additional components of metabolic syndrome from a set of cardiovascular risk markers. METHODS AND RESULTS: The homeostasis model assessment of insulin resistance (HOMA-IR), C-reactive protein, fibrinogen, plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor, homocysteine, Haemoglobin A1c (HbA1c), and lipoprotein(a) were assessed in a population-based sample of 902 nondiabetic adult subjects. Those biomarkers that were associated with metabolic syndrome were evaluated by multiple regression analysis, along with other traditional cardiovascular risk factors. Confirmatory factor analysis (CFA) was used to test the hypothesis that both the established components of metabolic syndrome and the novel variables identified by the regression analysis were associated with a single underlying factor. HOMA-IR, PAI-1 and HbA1c were the only biomarkers independently related to metabolic syndrome. CFA validated a one-factor model that included these variables. Moreover, the indices of goodness of fit were better for this expanded model than those obtained for a previously validated one-factor model that was restricted to the conventional elements of the syndrome. CONCLUSIONS: These findings show that PAI-1 and HbA1c are singularly linked to metabolic syndrome. Their elevation is presumably another manifestation of the same pathophysiological mechanism that underlies the recognized traits of the syndrome.  相似文献   
55.

Objectives

To assess the results of lung transplantation (LT) in children under 17 years of age and identify factors affecting long-term survival.

Methods

A retrospective review was performed of 37 patients (<17 years) who had received a lung transplant between 1996 and 2007. Morbidity, mortality, and survival were analyzed by the Kaplan-Meier method and the log-rank test.

Results

There were 37 LTs: 30 bilateral, four lobar, two liver-lung, one unilateral. Indications for transplantation were: cystic fibrosis (n = 30), pulmonary fibrosis (n = 1), bronchiectasis (n = 1), Kartagener's syndrome (n = 1), bronchiolitis obliterans (n = 3), and pulmonary fibrosis due to radiotherapy-chemotherapy (n = 1). The intubation time and oxygenation index of donors were 49 ± 36 hours and 455 ± 83.5 mm Hg, respectively. Seventeen patients needed extracorporeal circulation (ECC) and 13 were coded as priorities. High blood pressure and renal failure were the most frequent complications. Overall survival rates were 65.7%, 59.4%, 56.1%, 44.5%, and 39.6% at 1, 2, 3, 5, and 10 years, respectively. Need for ECC (P = .001), surgical complications (P = .037), oxygenation index <450 mm Hg (P = .005), OLT in priority code (P = .04), and age of donor >16 years (P = .005) were associated with poor survival.

Conclusions

LT is an appropriate procedure for certain types of end-stage pediatric pulmonary pathologies, achieving acceptable long-term survival rates. When the procedure is carried out under a surgical priority code, it is associated with a high rate of perioperative morbidity and mortality and poorer long-term survival. Other factors that have a negative influence on survival include the need for ECC, surgical complications, an oxygenation index <450 mm Hg, and donor age >16 years.  相似文献   
56.
Loss of imprinting at insulin-like growth factor II (IGFII), in association with H19 silencing, has been described previously in a subgroup of Beckwith-Wiedemann syndrome (BWS) patients who have an elevated risk for Wilms' tumor. An equivalent somatic mutation occurs in sporadic Wilms' tumor. We describe a family with overgrowth in three generations and Wilms' tumor in two generations, with paternal inheritance of a cis-duplication at 11p15.5 spanning the BWS IC1 region and including H19, IGFII, INS, and TH. The duplicated region was below the limit of detection by high-resolution karyotyping and fluorescence in situ hybridization, has a predicted minimum size of 400 kb, and was confirmed by genotyping and gene-dosage analysis on a CytoChip comparative genomic hybridization bacterial artificial chromosome array. IGFII is the only known paternally expressed oncogene mapping within the duplicated region and our findings directly implicate IGFII in Wilms' tumorigenesis and add to the mutation spectrum that increases the effective dose of IGFII. Furthermore, this study raises the possibility that sporadic cases of overgrowth and Wilms' tumor, presenting with apparent gain of methylation at IC1, may be explained by submicroscopic paternal duplications. This finding has important implications for determining the transmission risk in these disorders.  相似文献   
57.
Hereditary non-polyposis colon cancer (HNPCC) is an autosomal dominant condition, caused by germline mutations in the mismatch repair genes, that presents with colorectal cancers at a young age, as well as extracolonic tumours. One of the causative mutations is the C1528T (Exon 13) mutation of the MLH1 gene. The purpose of this study is to document the cancer risk for subjects who carry this mutation. This is a prospective cohort study of 200 subjects who carry this mutation. We calculated the risk of developing colorectal cancer only in those subjects who had not undergone surveillance colonoscopy. The incidence of extracolonic cancers (for which surveillance is not routinely offered) was determined for the entire cohort. The results of the study are among the 71 subjects who did not undergo surveillance colonoscopy, colorectal cancers occurred in 36 (51%). They occurred at a median age of 44 years (range 17–73). Using Kaplan–Meier estimates, the risk of developing a colorectal cancer by age 65 was 92%. Eighteen subjects in the cohort of 200 were diagnosed with extracolonic tumours. The most common extracolonic malignancies were breast (6/98 women) and endometrial (3/98 women). Thus this mutation has a high penetrance for colorectal cancer, but is not associated with a high risk of developing extracolonic malignancies.  相似文献   
58.
59.
60.

Objective

To examine and compare the extent to which people with type 2 diabetes (T2DM) are achieving haemoglobin A1c (HbA1c), blood pressure (BP) and LDL cholesterol (LDL-C) treatment targets.

Methods

A review of databases (MEDLINE Ovid, Pubmed and Sabinet) was performed and limited to the following terms: type 2 diabetes mellitus AND guideline AND goal achievement for the years 2009 to 2014 (five years).

Results

A total of 14 studies (25 629 patients) were selected across 19 different countries. An HbA1c level of 7.0% (or less) was achieved by 44.5% of subjects (range 19.2–70.5%), while 35.2% (range 7.4–66.3%) achieved BP of 130/80 mmHg (or less), and 51.4% (range 20.0–82.9%) had an LDL-C level of either 2.5 or 2.6 mmol/l (100 mg/dl or less).

Conclusion

Despite guideline recommendations that lowering of HbA1c, BP and lipids to target levels in T2DM will lead to a reduction in morbidity and mortality rates, we found that control of these risk factors remains suboptimal, even across different settings.  相似文献   
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