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991.
美国心脏协会卒中委员会发布了关于急性缺血性卒中的现行治疗指南,其中包括应用重组组织型纤溶酶原激活物(rt—PA)行静脉溶栓的建议。尽管该药对改善神经功能预后有一定的疗效,但由于患者通常在发病3h后方能到达医院,往往已经超过了用药的时间窗。因此,大部分缺血性卒中患者未能接受rt—PA治疗。目前研究认为,增加rt—PA治疗例数的最可能方法就是延长治疗时间窗。 相似文献
992.
Lindsay JL Forbes Carol McNaughton Nicholls Louise Linsell Jenny Graham Charlotte Tompkins Amanda J Ramirez 《BMC medical research methodology》2010,10(1):110
Background
The purpose of this study was to explore women's views of the design of a large pragmatic cost-effectiveness randomised controlled trial of the policy of offering a health professional-delivered intervention to promote early presentation with breast symptoms in older women and thereby improve survival, with a view to informing protocol development. The trial will recruit over 100,000 healthy women aged 67+, and outcome data will be collected on those who develop breast cancer. The scale of the trial and the need for long-term follow-up presented a number of design challenges in relation to obtaining consent, ascertaining and contacting participants who developed breast cancer, and collecting outcome data. 相似文献993.
994.
冠脉旁路移植术后康复1018例 总被引:1,自引:0,他引:1
1临床资料 1997-01/2004-12我院共完成冠脉旁路移植术(coronary artery bypass graft,CABG)1018(男888,女130)例,60岁以上582例(57.1%),70岁以上217例(21.3%),最大年龄86岁;非体外循环冠状动脉旁路移植术(OPCAB)510例,体外循环下冠状动脉旁路移植术(CCABG)508例;不稳定性心绞痛852例,术前同时合并其他疾病784例(77.1%),高血压病500例, 相似文献
995.
Ingrid P Vogelaar Rachel S van der Post Tanya M Bisseling J Han JM van Krieken Marjolijn JL Ligtenberg Nicoline Hoogerbrugge 《Hereditary cancer in clinical practice》2012,10(1):18
Worldwide, gastric cancer is one of the most common forms of cancer, with a high morbidity and mortality. Several environmental factors predispose to the development of gastric cancer, such as Helicobacter pylori infection, diet and smoking. Familial clustering of gastric cancer is seen in 10% of cases, and approximately 3% of gastric cancer cases arise in the setting of hereditary diffuse gastric cancer (HDGC). In families with HDGC, gastric cancer presents at relatively young age. Germline mutations in the CDH1 gene are the major cause of HDGC and are identified in approximately 25-50% of families which fulfill strict criteria. Prophylactic gastrectomy is the only option to prevent gastric cancer in individuals with a CDH1 mutation. However, in the majority of families with multiple cases of gastric cancer no germline genetic abnormality can be identified and therefore preventive measures are not available, except for general lifestyle advice. Future research should focus on identifying new genetic predisposing factors for all types of familial gastric cancer. 相似文献
996.
997.
998.
Andreacci JL Robertson RJ Dubé JJ Aaron DJ Balasekaran G Arslanian SA 《Pediatric research》2004,56(5):706-713
The purpose of this investigation was to determine whether maximal oxygen consumption (VO2max) differed between two selected groups of black and white children and whether a difference existed to determine whether it was related to hematologic profiles, body composition, and/or physical activity/inactivity level. Forty-five prepubertal and 42 pubertal, clinically normal black and white children participated. Dual-energy x-ray absorptiometry was used to determine body composition. A computed tomography scan of the abdomen was used to determine visceral adipose tissue and s.c. adipose tissue. Daily physical activity/inactivity was assessed by questionnaire. Black prepubertal and pubertal children had lower VO2max values when compared with white children (28.8 +/- 7.8 versus 35.0 +/- 6.5 mL . kg(-1) . min(-1), p < 0.01; 33.7 +/- 6.4 versus 40.4 +/- 10.2 mL . kg(-1) . min(-1), p < 0.05; respectively). Black prepubertal and pubertal children had lower Hb concentrations ([Hb]) and hematocrits than white children (prepubertal: 12.1 +/- 0.5 versus 12.8 +/- 0.9 g/dL, p < 0.001; 35.6 +/- 1.4 versus 37.4 +/- 2.3%, p < 0.01, respectively; pubertal: 13.0 +/- 0.9 versus 13.6 +/- 0.7 g/dL, p < 0.05; 37.7 +/- 2.5 versus 39.5 +/- 2.1%, p < 0.05, respectively). In conclusion, these findings indicate that black prepubertal and pubertal children had lower VO2max when compared with their white peers matched for age, pubertal stage, and body mass index. This difference in VO2max could be attributed at least in part to comparatively lower [Hb] and more sedentary lifestyle in the black children. Further investigations should study Hb flow rate (a function of [Hb] x maximal cardiac output) in black and white children as it relates to VO2max. 相似文献
999.
Background
Immunoglobulin rearrangement involves random and imprecise processes that act to both create and constrain diversity. Two such processes are the loss of nucleotides through the action of unknown exonuclease(s) and the addition of P nucleotides. The study of such processes has been compromised by difficulties in reliably aligning immunoglobulin genes and in the partitioning of nucleotides between segment ends, and between N and P nucleotides.Results
A dataset of 294 human IgM sequences was created and partitioned with the aid of a probabilistic model. Non-random removal of nucleotides is seen between the three IGH gene types with the IGHV gene averaging removals of 1.2 nucleotides compared to 4.7 for the other gene ends (p < 0.001). Individual IGHV, IGHD and IGHJ gene subgroups also display statistical differences in the level of nucleotide loss. For example, within the IGHJ group, IGHJ3 has average removals of 1.3 nucleotides compared to 6.4 nucleotides for IGHJ6 genes (p < 0.002). Analysis of putative P nucleotides within the IgM and pooled datasets revealed only a single putative P nucleotide motif (GTT at the 3' D-REGION end) to occur at a frequency significantly higher then would be expected from random N nucleotide addition.Conclusions
The loss of nucleotides due to the action of exonucleases is not random, but is influenced by the nucleotide composition of the genes. P nucleotides do not make a significant contribution to diversity of immunoglobulin sequences. Although palindromic sequences are present in 10% of immunologlobulin rearrangements, most of the 'palindromic' nucleotides are likely to have been inserted into the junction during the process of N nucleotide addition. P nucleotides can only be stated with confidence to contribute to diversity of less than 1% of sequences. Any attempt to identify P nucleotides in immunoglobulins is therefore likely to introduce errors into the partitioning of such sequences. 相似文献1000.
D.?A.?Moreno?EgeaEmail author J.?A.?Torralba?Martinez G?Morales?Cuenca J.?De?Miquel JG?Martín?Lorenzo JL?Aguayo?Albasini M.?Canteras?Jordana 《Hernia》2004,8(3):208-212
The popularity of laparoscopic repair of ventral hernias is increasing due to the apparent advantages of the procedure, but this approach is still a controversial technique. The aim of our study was to evaluate the mortality rate of laparoscopic ventral hernia repair and analyse the literature. The authors performed a prospective study in 90 patients with ventral hernia who were treated by laparoscopic repair. Clinical parameters and intra- and postoperative complications were evaluated. A case of mortality was reported due to a nonrecognised bowel injury. The mean follow-up (100%) was 42 months (range: 1–5 years). A bibliographical analysis was carried out (MEDLINE). Four bowel injuries were presented (4.4%): three recognised, which required conversion (two treated with minilaparotomy and completed afterwards by laparoscopy, and one by laparotomy); and one nonrecognised, which was re-operated on but evolved to sepsis and multiorgan failure and resulted in death in 48 h (1.1%). Four further mortality rates have been documented in the literature (0.6%, 1.1%, 3.1%, and 3.4% of their series). Bowel injury and mortality show a statistically significant tendency to decrease with the number of operations (P<0.05). In conclusion, in our study the risk of mortality with laparoscopic ventral hernia repair has been higher than 1%, which must be made known. It is a risk that depends on the surgeons experience but which does not seem to be predictable. 相似文献