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41.
To examine the association of low-grade systemic inflammation with diabetes, as well as its heterogeneity across subgroups, we designed a case-cohort study representing the approximately 9-year experience of 10,275 Atherosclerosis Risk in Communities Study participants. Analytes were measured on stored plasma of 581 incident cases of diabetes and 572 noncases. Statistically significant hazard ratios of developing diabetes for those in the fourth (versus first) quartile of inflammation markers, adjusted for age, sex, ethnicity, study center, parental history of diabetes, and hypertension, ranged from 1.9 to 2.8 for sialic acid, orosomucoid, interleukin-6, and C-reactive protein. After additional adjustment for BMI, waist-to-hip ratio, and fasting glucose and insulin, only the interleukin-6 association remained statistically significant (HR = 1.6, 1.01-2.7). Exclusion of GAD antibody-positive individuals changed associations minimally. An overall inflammation score based on these four markers plus white cell count and fibrinogen predicted diabetes in whites but not African Americans (interaction P = 0.005) and in nonsmokers but not smokers (interaction P = 0.13). The fully adjusted hazard ratio comparing white nonsmokers with score extremes was 3.7 (P for linear trend = 0.008). In conclusion, a low-grade inflammation predicts incident type 2 diabetes. The association is absent in smokers and African-Americans.  相似文献   
42.
Carones F  Vigo L  Carones AV  Brancato R 《Ophthalmology》2001,108(10):1732-1737
PURPOSE: To evaluate the results of photorefractive keratectomy (PRK) enhancements in eyes previously treated by myopic laser in situ keratomileusis (LASIK) showing an undercorrection due to either a refractive regression or a primary undercorrection, when an in-the-bed enhancement was not advisable because of residual stromal thickness limitations. DESIGN: Noncomparative, prospective, interventional case series. PARTICIPANTS: Seventeen eyes of 17 patients previously treated by LASIK for a spherical equivalent (SE) correction of -8.125 to -12.50 diopters (D; mean, -9.45 +/- 1.01 D), that after a follow-up of 6 to 14 months ended up with a refraction of -1.50 to -3.75 D (SE; mean, -2.48 +/- 0.74 D). Intended flap thickness was 160 microm for all eyes. In all cases, the residual stromal bed under the flap was considered too thin (255-305 microm) to allow an in-the-bed enhancement without exceeding an assumed safety thickness limit (250 microm). INTERVENTION: Eyes were treated by PRK at least 6 months after LASIK. The PRK ablation parameters (diameter, attempted correction) were selected to avoid theoretical flap perforation. The deepest ablation was 60 microm, for a -3.75-D correction. We used a Bausch & Lomb 217 C excimer laser (Bausch & Lomb, Rochester, New York). MAIN OUTCOME MEASURES: Refraction, uncorrected and best-corrected visual acuity (BCVA), slit-lamp evidence of corneal opacity or other visible complications, and corneal topography. RESULTS: Although the initial postoperative period was characterized by very satisfactory refractive results (mean SE error at 1 month, -0.04 +/- 0.37 D; range, +0.75 to -0.625 D), during follow-up, a dense haze (grade 3 and 4) developed in 14 eyes (82.3%) that induced a further myopic regression (SE, -1.725 to -5.50 D; mean, -3.11 D) and BCVA loss (two to six lines). These 14 eyes underwent a further surgical treatment to remove the severe haze at 3 to 10 months after PRK. CONCLUSIONS: Based on these results, we strongly advise against PRK as a possible option to correct eyes previously treated by myopic LASIK that resulted in an undercorrection.  相似文献   
43.
Freshwater snails of the family Lymnaeidae are of a great parasitological importance because of the very numerous helminth species they transmit, mainly trematodiases of large medical and veterinary impact. The present knowledge on the genetics of lymnaeids and on their parasite-host inter-relationships is far from being sufficient. The family is immersed in a systematic-taxonomic confusion. The necessity for a tool which enables species distinction and population characterization is evident. This paper aims to review the European Lymnaeidae basing on the second internal transcribed spacer ITS-2 of the nuclear ribosomal DNA. The ITS-2 sequences of 66 populations of 13 European and 1 North American lymnaeid species, including the five generic (or subgeneric) taxa Lymnaea sensu stricto, Stagnicola, Omphiscola, Radix and Galba, have been obtained. The ITS-2 proves to be a useful marker for resolving supraspecific, specific and population relationships in Lymnaeidae. Three different groupings according to their ITS-2 length could be distinguished: Radix and Galba may be considered the oldest taxa (370-406 bp lengths), and Lymnaea s. str., European Stagnicola and Omphiscola (468-491 bp lengths) the most recent, American Stagnicola and Hinkleyia being intermediate (434-450 bp lengths). This hypothesis agrees with the phylogeny of lymnaeids based on palaeontological data, chromosome numbers and radular dentition. ITS-2 sequences present a conserved central region flanked by two variable lateral regions corresponding to the 5' and 3' ends. The number of repeats of two microsatellites found in this conserved central region allows to differentiate Radix from all other lymnaeids. Phylogenetic trees showed four clades: (A) Lymnaea s. str., European Stagnicola and Omphiscola; (B) Radix species; (C) Galba truncatula; and (D) North American stagnicolines. ITS-2 results suggest that retaining Stagnicola as a subgenus of Lymnaea may be the most appropriate and that genus status for Omphiscola is justified. Radix shows a complexity suggesting different evolutionary lines, whereas G. truncatula appears to be very homogeneous. North American and European stagnicolines do not belong to the same supraspecific taxon; the genus Hinkleyia may be used for the American stagnicolines. Genetic distances and sequence differences allowed us to distinguish the upper limit to be expected within a single species and to how different sister species may be. S. palustris, S. fuscus and S. corvus proved to be valid species, but S. turricula may not be considered a species independent from S. palustris. Marked nucleotide divergences and genetic distances detected between different S. fuscus populations may be interpreted as a process of geographic differentiation developping in the present. Among Radix, six valid species could be distinguished: R. auricularia, R. ampla, R. peregra (=R. ovata;=R. balthica), R. labiata, R. lagotis and Radix sp. The information which the ITS-2 marker furnishes is of applied interest concerning the molluscan host specificity of the different trematode species. The phylogenetic trees inferred from the ITS-2 sequences are able to differentiate between lymnaeids transmitting and those non-transmitting fasciolids, as well as between those transmitting F. hepatica and those transmitting F. gigantica. The Fasciola specificity is linked to the two oldest genera which moreover cluster together in the phylogenetic trees, suggesting an origin of the Fasciola ancestors related to the origin of this branch. European Trichobilharzia species causing human dermatitis are transmitted only by lymnaeids of the Radix and Lymnaea s. str.-Stagnicola groups. Results suggest the convenience of reinvestigating compatibility differences after accurate lymnaeid species classification by ITS-2 sequencing. Similarly, ITS-2 sequencing would allow a step forward in the appropriate rearrangement of the actual systematic confusion among echinostomatids.  相似文献   
44.
After a review of the methods employed for arthrographic visualization of cruciate ligaments (CL), the authors present a new technique to separately study the anterior and posterior CL during traction. This technique enables to obtain a good visualization of CL and a good diagnostic accuracy; it can radiographically demonstrate a pathologic sagittal instability of the knee; it is easy to perform and is easily repeatable in different patients.  相似文献   
45.
The association between breastfeeding and diarrhoeal morbidity was examined in a prevalence study of 5502 children aged 6-71 months from rural and urban Bangladesh. Breastfeeding was found to be associated with reduced prevalence of diarrhoea. This association was most pronounced at the age of six months and declined linearly to zero at approximately 30 months of age; thereafter, breastfeeding was increasingly associated with diarrhoeal illness. The linear association was found only among those children who have no access to modern health services and information, when controlling for urban and rural differences. The literature provides two opposing explanations for the positive association of prolonged breastfeeding with diarrhoeal illness. The first explanation suggests that breastfeeding can be seen as mothers' response to children's poor health. The second explanation incriminates sub-optimal child feeding practices, characterised by prolonged breastfeeding and inadequate quality and quantity of complementary foods, as the cause of malnutrition and diarrhoea. Further studies are needed to identify which explanation is correct, given the public health implications in terms of children's survival, growth and development.  相似文献   
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目的:分析肾移植术后常见并发症肾功能延迟恢复的诱因,并观察术后血液净化干预所发挥的临床效应。方法:选择1996—12/2006—12在解放军第三军医大学大坪医院野战外科研究所泌尿外科明确诊断为肾移植术后肾功能延迟恢复的患者193例,其中接受尸肾移植192例,活体肾移植1例,均知情同意。根据患者的临床资料,分析术后肾功能延迟恢复的主要原因。除5例因术前安置腹膜透析管继续采用腹膜透析外,其余均选择血液透析治疗,其中35例穿插接受过连续性肾脏替代治疗或血液透析滤过,8例血浆置换2-5次。终止透析的标准为每日尿量〉1500mL,血肌酐〈300μmol/L。分析术后肾功能延迟恢复的原因,观察接受透析治疗后肾功能延迟恢复患者的临床疗效。结果:193例患者全部进入结果分析。①术后肾功能延迟恢复的病因:急性肾小管坏死89例(46.1%),术后早期低血压42例(21.8%),排斥反应37例(19.2%),动静脉吻合口狭窄9例(4-7%),尿路梗阻8例(4.1%),动脉过长扭曲5例(2.6%),环孢素A肾毒性2例(1.0%),髂内动脉粥样硬化斑块阻塞1例(0.5%)。(④术后肾功能转归:移植肾功能恢复正常者145例(75.1%);术后3个月血肌酐135-300μmol/L29例(15.3%);〉300μmol/L15例(7.8%);因超急性排斥反应切除移植肾2例(1%),肺部重症感染死亡2例(1%)。③术后接受血液透析次数:术后接受血液透析189例,透析1—5次移植肾功能恢复正常20例(13.8%);6-10次41例(28.3%);11-20次82例(56.6%);21-25次2例(1.4%);〉25次44例,仅1例恢复正常(0.7%),其余43例患者带肾存活。结论:急性肾小管坏死、术后早期低血压和排斥反应是引起肾移植术后肾功能延迟恢复的主要原因。在肾功能延迟恢复患者确定以血液净化为主的方案后,绝大多数移植肾功能可以恢复。  相似文献   
50.
目的:慢性移植肾失功是导致后期移植肾丧失的重要原因之一,文章拟探讨慢性移植肾失功的相关因素及防治措施。方法:①选择1993-12/2006-12于解放军第三军医大学大坪医院行肾移植术后发生慢性移植肾失功患者356例,回顾性分析其临床资料。②调整免疫抑制剂方案,停服硫唑嘌呤、环孢素A或减少环孢素A30% ̄50%剂量,改用他克莫司0.5 ̄1mg/(kg·d)、霉酚酸酯1 ̄2g/d、西罗莫司1 ̄2mL/d等药;控制血糖、血脂、血压,抗凝及补充鱼肝油丸;服用雷公藤、百令胶囊或尿毒清等中药,给予低蛋白、低磷及高维生素、氨基酸饮食;必要时手术切除移植肾。③分析肾移植术后发生慢性移植肾失功的危险因素并观察其治疗结果。结果:①慢性移植肾失功的危险因素:急性排斥反应254例(71.35%),巨细胞病毒感染65例(18.26%),移植肾肾小球肾炎21例(5.9%),药物中毒(环孢素A/他克莫司)9例(2.53%),高血压/高血脂/高血糖5例(1.41%),肾单位减少(高龄供肾/性别差异)2例(0.56%)。②治疗结果:切除移植肾194例(54.49%),带肾存活、恢复血液透析87例(24.44%),经治疗血肌酐维持在200 ̄300μmol/L63例(17.70%),死亡12例(3.37%)。结论:急性排斥反应是引起肾移植术后慢性移植肾失功的主要因素。提高供肾质量,严格组织配型,减少移植肾功能延迟恢复的发生,制定个体化免疫方案,定期监测药物浓度及肝肾功能,预防巨细胞病毒感染,可减少慢性移植肾失功的发生。  相似文献   
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