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181.
305例尿石成份分析及预防对策 总被引:13,自引:3,他引:10
目的研究一种快速、简便的方法对泌尿系结石进行分析,并探讨其防治方法。方法用化学常量法对305例患者的尿石标本进行化学成份测定,并结合临床资料进行分析。结果发现结石发病男性多于女性(比例为3.2∶1),20~50岁多发,上尿路结石多于下尿路结石(5.4∶1)。结石中草酸钙检出率达82%,尿酸盐55.2%,磷酸钙48.6%,磷酸镁铵与碳酸磷灰石则多见于泌尿系感染病例,胱氨酸结石少见。结论化学常量法分析泌尿系结石简便、快捷、准确。结石成份分析对于了解结石成因、预防结石复发具有一定的意义。 相似文献
182.
梗阻性脑积水侧脑室及室周脑组织生物力学响应的有限元分析 总被引:1,自引:0,他引:1
目的运用有限元方法对梗阻性脑积水进行计算机模拟,研究分析侧脑室及室周脑组织的生物力学响应及其所产生的病理生理影响。方法依据正常国人颅脑MRI轴位T2加权图像获取解剖信息,在有限元软件ANSYS中生成包含侧脑室前、后角和体部的半侧脑层面的二维有限元模型。模拟脑组织为固、液两相物质组成的线性多孔弹性材料,设定生物力学特性参数及边界条件和初始条件,施加载荷,运用有限元软件ABAQUS进行计算求解,以云图形式输出结果。结果有限元模型动态模拟了梗阻性脑积水侧脑室各部的扩张过程,直观显示出各个时间步室周脑组织内的应力类型及分布、各部的应变和位移。结论膨胀性应力集中引起角部脑水肿;梗阻性脑积水早期侧脑室角部形态变化最明显;体部附近脑组织结构容易受压移位。这些生物力学响应是室内压增高的结果,也与侧脑室的解剖形态密切相关。 相似文献
183.
Kun Hwang MD PhD Ei Tae Kim MD Se Il Lee MD DMSc 《The Journal of foot and ankle surgery》2005,44(6):473-477
The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence. 相似文献
184.
应用自动化图象分析仪对131个胃粘膜肠型病灶(单纯性肠化27个;异型增生:轻度30,中度35个,重度20个;肠型胃癌19个)进行定量分析。以单个腺管内细胞核总面积与细胞面积之比(ING)作为反映细胞核大小、数量及覆层排列程度的客观定量指标。结果发现:单纯性肠化(对照组)0.165±0.025,轻度异型增生0.21±0.023,中度异型增生0.259±0.026,重度异型增生0.32±0.028,分化型胃癌0.371±0.052,各组ING值呈正态,各组间的均值有非常显著的差异(P<0001)。因而,ING可作为胃粘膜癌前病变诊断的指标。 相似文献
185.
Masahiro Miyashita Junko Otsuki Yosuke Hanai Yoshiaki Nakagawa Hisashi Miyagawa 《Toxicon》2007,50(3):428-437
Scorpion venoms are composed of a number of neurotoxic peptides. A variety of toxins have been isolated from the venoms of scorpions of the family Buthidae, however, little interest has been paid to non-Buthidae scorpions. In this study, we examined the toxicity of the venom of Liocheles australasiae (Hemiscorpiidae) to mice and crickets, and characterized the peptide components by HPLC and mass spectrometry. Over 200 components were detected in the L. australasiae venom by LC/MS analysis, with components of molecular masses ranging from 500 to 5000 Da being particularly abundant. A number of peptides contained two to four disulfide bridges, which was estimated based on the mass difference after derivatization of Cys residues. A peptide having a monoisotopic molecular mass of 7781.6 Da and four disulfide bridges was isolated from the venom. The peptide has a primary structure similar in terms of the position of eight Cys residues to those observed in several peptides found from scorpions, ticks and insects, although biological roles of these peptides are unknown. 相似文献
186.
美国头颈癌患者生存资料分析 总被引:4,自引:2,他引:2
为使国内头颈癌生存分析的基本方法与国际一致,规范生存率分析的基本方法,以利于相互比较.本文以文字及表格方式,简述生存分析基本术语的概念、意义和应用,并介绍2002年第6版《美国头颈部肿瘤TNM分期》的1-5年观察生存率、相对生存率。 相似文献
187.
Marlene S. See M. R. Foxton N. A. Miedzianowski-Sinclair C. E. Roberts C. Nduka 《European journal of plastic surgery》2007,29(8):387-393
The nasolabial fold is a significant facial landmark. Its size, shape, and symmetry are important in facial reanimation surgery,
while effacement is an important goal in rejuvenation surgery. However, quantitative data for the nasolabial fold volume (NLFV)
and depth is still unavailable. We present a new method of measurement using 3D color speckle stereophotogrammetry and its
application in the assessment of NLFV. The VECTRA-3D system was validated to determine its minimum resolution and accuracy.
Normal volunteers aged 13–84 years (n = 87) were imaged in repose. Mother–daughter pairs (n = 15, aged 13–61) were imaged in the upright and supine positions. All data were processed using custom software and analyzed
by linear regression and nonparametric tests as appropriate. NLFV varied from 0.0026 to 0.2306 ml. There was significant correlation
between NLFV and age (r = 0.7269, p < 0.0001). Men had significantly higher NLFV than women across all ages. There was no significant difference between the
left and right NLFV. NLFV altered significantly from upright to supine in all subjects (p = 0.0012). However, the mothers increased their NLFV by 32% from supine to upright postures, which was a greater change than
observed in their daughters. We have demonstrated a rapid, objective, and non-invasive assessment tool for facial reanimation
and rejuvenation surgery. We have quantified the effects of age and posture on NLFV, and the efficacy and longevity of rejuvenation
procedures are currently under investigation. 相似文献
188.
目的探讨乳头溢液的渗断和治疗方法,为合理的治疗提供科学依据。方法回顾分析手术治疗的207例乳头溢液病例资料。结果(1)在非哺乳期间发生乳头溢液多属病理性溢液;(2)通过美蓝法或平针头指示法行区段切除术,安全准确。结论(1)乳头溢液特别足血性溢液应手术治疗.对早期发现和早期治疗乳腺癌有鼋要的临床意义。(2)乳头溢液伴肿块者,不沧年龄大小、溢液性质均应手术治疗。 相似文献
189.
What factors influence survival in patients with unresected synchronous liver metastases after resection of colorectal cancer? 总被引:3,自引:0,他引:3
N. Chafai C. L. H. Chan E. L. Bokey O. F. Dent G. Sinclair P. H. Chapuis 《Colorectal disease》2005,7(2):176-181
OBJECTIVE: The aim of this study was to determine whether the survival of patients with untreated synchronous liver metastases after resection of a colorectal cancer was associated with any features of the primary tumour. METHODS: Information for 398 consecutive patients with unresected liver metastases in the period 1971-2001 was examined by multivariate survival analysis. RESULTS: Of 19 clinical and pathological variables considered, survival was independently associated only with residual tumour in a line of resection (hazard ratio (HR) 1.95), venous invasion (HR 1.87), right colonic tumour (HR 1.68), lymph node metastasis (HR 1.54), and extra-hepatic metastasis (HR 1.16); 8.3% of patients had none of these adverse features. Their 2-year overall survival rate was 39.2%, compared with only 16.5% (P < 0.001) in those with one or more adverse features. CONCLUSIONS: These findings may assist in selecting patients most likely to benefit from treatment of hepatic metastases and in counselling patients and their relatives. 相似文献
190.
铰链式冠外附着体的结构强度分析 总被引:2,自引:0,他引:2
目的探讨铰链式冠外附着体设计的合理性.方法采用有限元应力分析的实验方法,分析铰链式冠外附着体阳性结构L形球体的应力分布情况,对其结构强度进行测试.结果在附着体阳性结构L形球体的转角处应力最大,应力值为321.847MPa.结论该铰链式附着体的结构强度符合临床设计要求. 相似文献