肾细胞癌淋巴结转移预测指标的Logistic回归分析

目的：研究肾细胞癌淋巴结转移的危险因素,并建立Logistic回归模型。方法：2002年2月-2010年10月我院手术治疗的肾细胞癌163例,对其临床病理资料进行单因素和多因素的Logistic回归分析。结果：淋巴结转移的发生率为20．9％（34／163）。单因素分析显示：肿瘤大小、临床分期、Fuhrman核分级和贫血与肾细胞癌淋巴结转移的风险有关（P〈0．05）;多因素分析显示：肿瘤大小、临床分期和Fuhrman核分级是RCC淋巴结转移独立的风险因素。结论：肾细胞癌淋巴结转移的风险与肿瘤大小、临床分期和Fuhrman核分级有关,Logistic回归模型对于判断预后、指导术后治疗及随访方案的制订具有重要作用。     

骨科住院患者死亡原因的研究分析

目的:对骨科住院患者死亡原因进行研究分析。方法:本研究采用回顾性病史分析方法,对我院2002年11月至2011年3月期间的骨科住院患者死亡病例进行统计分析。结果:在此期间共发生死亡病例27例。死亡的原因分别是:呼吸系统衰竭、急性心肌梗死、急性脑血管病、多器官衰竭以及出血性休克。结论:年龄在70-80岁之间的股骨颈骨折病人的死亡率最高,属于高危人群;手术的治疗干预并没有提高患者的死亡率;患者的死亡时间并没有在特定的时间段出现高值。肺栓塞是导致骨科病人死亡的高危因素。通过采取有效的预防措施,可以降低骨科住院患者的死亡率。     

影响侧脑室脑膜瘤手术疗效的多因素分析

目的：探讨影响侧脑室脑膜瘤手术疗效的因素,从而更好的促进侧脑室脑膜瘤的手术治疗。方法：回顾性分析侧脑室脑膜瘤显微手术30例的临床病理特征与顸后情况,其中KPS〉70分表示为预后良好,KP懿70分表示为预后不良。对各性别、年龄、部位、肿瘤大小、病理分型及术后有无并发症因素与预后进行χ^2检验与用Logistic回归分析其影响因素。结果：单因素分析表明肿瘤部位、病理分型及术后有无并发症对侧脑室脑膜瘤的预后有明显影响,P〈0．05,差异有统计学意义。经Logistic回归分析,最终进入模型的影响因素有2个,它们分别是肿瘤部位和术后有无并发症,其P值均小于0．05。结论：在显微手术下,侧脑室脑膜瘤大部分可以全切并取得了较好的远期疗效。肿瘤部位和术后有无并发症是影响预后的一个重要因素,及时处理并发症能显著地改善预后。     

通用选择指数的通径分析化模型

通过对各种选择指数的通径分析化模型进行系统化的研究,建立了通用选择指数的通径分析化模型,并给出了各种选择指数及其通径分析化的统一表示形式．用该模型可以充分利用各种信息来源,特别是在对各种信息来源需作各种约束时,为选种和评定优种提供了行之有效的计算方法和统一程序,避免了在实际应用中因计算体系不同而导致的混乱．     

围术期管理对手术相关危险因素影响研究

目的 探讨手术并发症、死亡相关危险因素和改进围术期安全质量管理对其的影响及意义。方法 对可能引发术后并发症及死亡的危险因素进行单元性分析和多元性回归分析,并对实施新的管理制度和改进管理模式前、后手术并发症及死亡率作对照分析。结果 单元性与多元性回归分析显示,肥胖、吸烟史、麻醉风险评估≥2级、切口类型≥Ⅱ和手术时间>3 h与发生术后并发症及死亡有显著相关性（P在0.000～0.019以内）,而且均为诱发的高危因素(OR在2.860～9.710以内)。改进管理制度和管理模式后手术并发症发生率分别下降1.40% ( P=0.002)、1.30%( P=0.000)、1.62%（P=0.000),实施手术安全质量信息化管理系统之后手术死亡率降低了0.16%(P=0.002)。结论 加强和改进围术期安全质量管理能够有效预防和控制术后并发症及死亡,对持续改进手术质量、保障病人安全具有重要的现实意义。     

原发性肝癌根治术后病人肺部并发症危险因素的单因素及Logistic分析

目的:探讨原发性肝癌根治术后病人肺部并发症发生的危险因素。方法:收集2011年3月至2014年2月间因原发性肝癌行肝癌根治术病人120例,根据有无并发症将两组病人分为肺部并发症和无肺部并发症组,对病人的一般情况、术前检查及手术情况设置变量首先用单因素方法筛选与肝癌根治术后肺部并发症相关的危险因素,进一步行多因素logistic分析这些相关危险因素中的独立危险因素。结果:入组病人中术后有25例(20.83%)发生了肺部并发症。单因素分析结果显示肝癌根治术后肺部并发症发生的危险因素有:慢性呼吸道疾病史、术前2周呼吸道感染史、术前白蛋白水平、手术时间、麻醉时间、术中出血量及术后使用镇痛泵(P0.05)。Logistic分析显示肝癌根治术后肺部并发症发生的独立危险因素为:慢性呼吸道疾病史、术前白蛋白水平及术后使用镇痛泵(P0.05)。结论:原发性肝癌根治术患者存在术后肺部并发症危险因素,临床工作中对其进行评估可减少或避免发生并发症。     

89例喉鳞癌患者术后生存的cox模型多因素分析

目的：探讨影响喉癌手术后生存的相关危险因素。方法：回顾1997年1月-2006年12月在我科行喉癌手术治疗的89例患者,分析肿瘤因素、宿主因素及辅助治疗因素对术后生存的影响。结果：全组术后5年生存率70．7％（63／89）,肿瘤T分期、颈部淋巴结是否转移及手术切缘状态是影响喉癌手术预后的独立危险因素。对于进展期喉癌,如适应症选择合理,行全喉切除及根治性喉部分切除预后无统计学差异。结论：早期诊断并选择合理的术式,尤其一些保留或重建喉功能的术式加合理的颈淋巴结清扫,同时确保手术安全切缘是提高喉癌术后肿瘤和喉功能效果的关键。     

肾细胞癌淋巴结转移预测指标的Logistic 回归分析

目的:研究肾细胞癌淋巴结转移的危险因素,并建立Logistic回归模型。方法:2002年2月～2010年10月我院手术治疗的肾细胞癌163例,对其临床病理资料进行单因素和多因素的Logistic回归分析。结果:淋巴结转移的发生率为20.9%(34/163)。单因素分析显示:肿瘤大小、临床分期、Fuhrman核分级和贫血与肾细胞癌淋巴结转移的风险有关(P<0.05);多因素分析显示:肿瘤大小、临床分期和Fuhrman核分级是RCC淋巴结转移独立的风险因素。结论:肾细胞癌淋巴结转移的风险与肿瘤大小、临床分期和Fuhrman核分级有关,Logistic回归模型对于判断预后、指导术后治疗及随访方案的制订具有重要作用。     

Cox回归模型在肝癌病人生存分析中应用的研究

生存时间是癌症患者和临床医师共同关心的焦点,也是临床癌症诊治工作的重要指标之一．生存分析是研究多种因素与生存时间的关系以及关系程度的大小．Cox回归模型是生存分析中常用的方法之一．本文利用Cox回归模型对786名肝癌患者进行生存分析,确定影响肝癌患者预后的主要因素是癌栓、肝癌部位、治疗方式、肝脏储备功能、端粒酶活性、细胞增殖活性、γ-GT(γ-谷氮酰转肽酶)、术后复发等．为临床研究延长肝癌病人的生存期,提高其生存率提供了有力的依据．     

不同麻醉方式处理休克病人的46例临床研究

目的：观察并分析对休克病人实施不同的麻醉处理方式的临床效果。方法：选取2012年2月至2013年2月我院收治的临床休克患者46例,选择性的实施不同的麻醉方式进行处理。比较患者麻醉前后各项监测指标的变化情况。结果：实施麻醉术后,有43例患者表现为正常;2例因大出血抢救无效而死亡;1例因多器官功能发生衰竭而死亡;术中未发生因麻醉不当而导致的患者死亡。术后生命体征正常的患者明显高于死亡的患者,差异有统计学意义（P〈0．05）。患者手术之后各项指标显著优于手术前,差异有统计学意义（P〈0．05）。结论：对临床休克病人采取合适的麻醉方式,可以有效的辅助手术顺利进行,提高手术的成功率和患者的存活率,值得临床推广。     

柑桔全爪螨自然种群动态的模拟模型

本文运用时间序列分析方法对上海市长兴岛前卫农场柑桔园内柑桔全爪螨及其天敌江原钝绥螨的种群动态进行分析和模拟,分别建立了关于柑桔全爪螨及其天敌种群数量动态的作用,预测柑桔全爪螨种群数量的变化趋势,模拟效果良好,对田间防治具有一定的参考价值。     

Segregation analysis detects a major gene controlling blood infection levels in human malaria.

The profound influence that the genetic makeup of the host has on resistance to malaria infection has been established in numerous animal studies. This genetic heterogeneity is one of the main causes of the difficulties in developing an effective malaria vaccine. Segregation analysis is the first step in identifying the nature of genetic factors involved in the expression of human complex diseases, as infectious diseases. To assess the role of host genes in human malaria, we performed segregation analysis of blood parasite densities in 42 Cameroonian families by using both the unified mixed model and the class D regressive model of analysis. The results provide clear evidence for the presence of a recessive major gene controlling the degree of infection in human malaria. Parameter estimates show a frequency of .44-.48 for the deleterious allele, indicating that about 21% of the population is predisposed to high levels of infection.     

A Genetic and Molecular Analysis of the 46c Chromosomal Region Surrounding the Fmrfamide Neuropeptide Gene in Drosophila Melanogaster

We have analyzed the FMRFamide neuropeptide gene region of Drosophila melanogaster. This gene maps to the 46C region of chromosome 2R; this interval previously was not well characterized. For this genetic and molecular analysis, we have used X-ray mutagenesis, EMS mutagenesis, and the recently reported local P element transposition method. We identified four overlapping deletions, two of which have proximal breakpoints that define a 50-60-kb region surrounding the FMRFamide gene in 46C. To this small region, we mapped three lethal complementation groups; 10 additional lethal complementation groups were mapped to more distal regions of 46CD. One of these groups corresponds to even-skipped, the other 12 are previously unidentified. Using various lines of evidence we excluded the possibility that FMRFamide corresponds to any of the three lethal complementation groups mapping to its immediate 50-60-kb vicinity. The positions of two of the three lethal complementation groups were identified with P elements using a local transposition scheme. The third lethal complementation group was excluded as being FMRFamide mutants by sequence analysis and by immunocytochemistry with proFMRFamide precursor-specific antibodies. This analysis has (1) provided a genetic map of the 46CD chromosomal region and a detailed molecular map of a portion of the 46C region and (2) provided additional evidence of the utility of local transposition for targeting nearby genes.     

Signature-tagged and directed mutagenesis identify PABA synthetase as essential for Aspergillus fumigatus pathogenicity

Signature-tagged mutagenesis (STM) is a method that has been used to screen for genes required for in vivo survival of pathogenic bacteria, but has not been used to investigate a eukaryotic pathogen in an animal model of disease. We have adapted STM to identify genes required for in vivo growth of the opportunistic fungal pathogen Aspergillus fumigatus. Using a mouse model of invasive pulmonary aspergillosis, we have isolated several mutant strains with defects in their ability to replicate in vivo. One strain unable to cause lethal infection was further characterized and found to have an insertion into the promoter of a gene (pabaA) encoding para-aminobenzoic acid synthetase, an enzyme catalyzing a late step in the biosynthesis of folate. The complete inability of this strain, and other pabaA- strains constructed in this study by targeted gene deletion, to cause lethal infection in mice confirms the importance of the folate synthesis pathway for in vivo survival of this pathogen. The successful application of STM to A. fumigatus demonstrates that in vivo genetic analysis of eukaryotic pathogens is feasible and could result in the identification of potential targets, such as para-aminobenzoic acid synthetase, for novel antifungal therapies.     

Intracellular calcium antagonist protects cultured peritoneal macrophages against anthrax lethal toxin-induced cytotoxicity

The lethal toxin ofBacillus anthracis is central to the pathogenesis of anthrax. Using primary cultures of mouse peritoneal macrophages, we have demonstrated that intracellular calcium release inhibitors protect against anthrax lethal toxin-induced cytotoxicity. The cytolytic effect of anthrax lethal toxin was markedly reduced by dantrolene, an inhibitor of calcium release from intracellular calcium stores. Pretreatment of macrophages with cyclosporin A, which has been shown to be a potent inhibitor of calcium release from mitochondria, also protected cells against cytotoxicity. These results indicate that calcium release from intracellular store may be an essential step for the propagation of anthrax lethal toxin-induced cell damage in macrophages. Thus our findings suggest that dantrolene, cyclosporin A, and possibly other drugs affecting intracellular calcium pools might be effectively preventing the toxicity from anthrax lethal toxin. This revised version was published online in July 2006 with corrections to the Cover Date.     

What's in a beach? Soil micromorphology of sediments from the Lower Paleolithic site of 'Ubeidiya, Israel

A micromorphological study of archaeological sediments from the early Pleistocene site of 'Ubeidiya (Jordan Valley, Israel) was conducted to provide microenvironmental detail for the hominin occupation contexts and investigate site formation issues. Previous research shows that the hominin groups occupied the marshes and pebbly beaches at the shores of a lake during a regressive period, but given that some portions of the lithic and faunal assemblages are abraded and others fresh, there remains a question of whether the archaeological assemblages are in situ or reworked, and if reworked, by what mechanisms and from where. The rates of sedimentation within the regressive cycle, by which we can learn about the frequency and duration of exposed surfaces amenable for hominin occupation is also unknown. Finally, the artificial nature of some of the pebbly layers has been questioned. The micromorphological analysis yielded the identification of twelve microfacies; the majority of these represent fluvially derived floodplain soils or distal mudflow deposits, and a minor number are sediments of lacustrine origin: mudflats and shallow subaqueous sediments. These represent the natural habitats of the 'Ubeidiya hominins and might serve as a reference to similar contexts of other early hominin sites. The sedimentary model proposed here entails the rapid deposition of fluvially derived low-energy sediments at and around the shoreline, followed by prolonged periods of exposure, during which surfaces stabilized within a relatively wet, marshy environment. This interpretation suggests that the abraded portions of the archaeological assemblages are a result of prolonged surface exposure rather than high-energy transport from a distant source or to wave reworking at the shoreline, and supports the consideration of these assemblages as archaeological palimpsests, with locally reworked fresh and abraded elements. No micromorphological evidence supporting anthropogenic agency in the formation of the pebbly layers was found. The entire regressive cycle entailed unvarying climatic conditions with seasonal fluctuations and episodic lacustrine incursions, and with a trend towards arid conditions in the end.     

A framework for biomechanics simulations using four-chamber cardiac models

Computational cardiac models have been extensively used to study different cardiac biomechanics; specifically, finite-element analysis has been one of the tools used to study the internal stresses and strains in the cardiac wall during the cardiac cycle. Cubic-Hermite finite element meshes have been used for simulating cardiac biomechanics due to their convergence characteristics and their ability to capture smooth geometries compactly–fewer elements are needed to build the cardiac geometry–compared to linear tetrahedral meshes. Such meshes have previously been used only with simple ventricular geometries with non-physiological boundary conditions due to challenges associated with creating cubic-Hermite meshes of the complex heart geometry. However, it is critical to accurately capture the different geometric characteristics of the heart and apply physiologically equivalent boundary conditions to replicate the in vivo heart motion. In this work, we created a four-chamber cardiac model utilizing cubic-Hermite elements and simulated a full cardiac cycle by coupling the 3D finite element model with a lumped circulation model. The myocardial fiber-orientations were interpolated within the mesh using the Log-Euclidean method to overcome the singularity associated with interpolation of orthogonal matrices. Physiologically equivalent rigid body constraints were applied to the nodes along the valve plane and the accuracy of the resulting simulations were validated using open source clinical data. We then simulated a complete cardiac cycle of a healthy heart and a heart with acute myocardial infarction. We compared the pumping functionality of the heart for both cases by calculating the ventricular work. We observed a 20% reduction in acute work done by the heart immediately after myocardial infarction. The myocardial wall displacements obtained from the four-chamber model are comparable to actual patient data, without requiring complicated non-physiological boundary conditions usually required in truncated ventricular heart models.     

pkDACLASS: Open source software for analyzing MALDI-TOF data

In recent years, mass spectrometry has become one of the core technologies for high throughput proteomic profiling in biomedical research. However, reproducibility of the results using this technology was in question. It has been realized that sophisticated automatic signal processing algorithms using advanced statistical procedures are needed to analyze high resolution and high dimensional proteomic data, e.g., Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) data. In this paper we present a software package-pkDACLASS based on R which provides a complete data analysis solution for users of MALDITOF raw data. Complete data analysis comprises data preprocessing, monoisotopic peak detection through statistical model fitting and testing, alignment of the monoisotopic peaks for multiple samples and classification of the normal and diseased samples through the detected peaks. The software provides flexibility to the users to accomplish the complete and integrated analysis in one step or conduct analysis as a flexible platform and reveal the results at each and every step of the analysis. AVAILABILITY: The database is available for free at http://cran.r-project.org/web/packages/pkDACLASS/index.html.     

The carboxy terminal WD domain of the pre-mRNA splicing factor Prp17p is critical for function

In Saccharomyces cerevisiae, Prp17p is required for the efficient completion of the second step of pre-mRNA splicing. The function and interacting factors for this protein have not been elucidated. We have performed a mutational analysis of yPrp17p to identify protein domains critical for function. A series of deletions were made throughout the region spanning the N-terminal 158 amino acids of the protein, which do not contain any identified structural motifs. The C-terminal portion (amino acids 160-455) contains a WD domain containing seven WD repeats. We determined that a minimal functional Prp17p consists of the WD domain and 40 amino acids N-terminal to it. We generated a three-dimensional model of the WD repeats in Prp17p based on the crystal structure of the beta-transducin WD domain. This model was used to identify potentially important amino acids for in vivo functional characterization. Through analysis of mutations in four different loops of Prp17p that lie between beta strands in the WD repeats, we have identified four amino acids, 235TETG238, that are critical for function. These amino acids are predicted to be surface exposed and may be involved in interactions that are important for splicing. Temperature-sensitive prp17 alleles with mutations of these four amino acids are defective for the second step of splicing and are synthetically lethal with a U5 snRNA loop I mutation, which is also required for the second step of splicing. These data reinforce the functional significance of this region within the WD domain of Prp17p in the second step of splicing.