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981.
以日摄氟量作为评价环境氟对人体健康影响的指标,比单一用空气、饮水和食物等的含氟量进行分析要合理。日摄氟量的计算各家不一,我们是将各点大气、饮水、粮食、蔬菜的实测含氟量分别乘大气12m~3、饮水3L、粮食0.6kg、蔬菜0.5kg,其和即是。研究结果表明:(1)成人的尿氟与日摄量呈非常显著的正相关(r=0.8809,P<0.01)。(2)成人的牙齿,各调查点的斑釉率和斑釉指数均随日摄氟量的增加而上升,二者分别与日摄氟量呈高度显著和显著的正相关(r=0.9048,p<0.01;r=0.8154,p<0.05)。(3)成人的胫腓骨、尺挠骨和骨盆的X线改变,以骨质增生、骨质的密度、结构改变和骨周肌腱韧带附着处钙化为主要表现,其改变的总阳性率与日摄氟量有一定的关系。 相似文献
982.
黄芪、莪术配伍对胃癌细胞COX-2表达的调节作用 总被引:2,自引:0,他引:2
目的:观察黄芪、莪术配伍对MKN-45细胞COX-2、PPlAR-Y、NF-KB的影响.方法:以黄芪、莪术配伍作用于MKN-45细胞,并设塞莱希布组、罗格列酮组、黄芪组、莪术组和空白组相对照.用MTT法观察各组药物对胃癌细胞的抑制率,用RT-PCR以及Western blot方法检测给药后人胃癌细胞COX-2、PPARy、NF-KB基因及COX-2蛋白表达的变化.结果:各组对COX-2和NF-KB的mRNA表达均有抑制作用,除莪术外对PPARy mRNA均有促表达作用,其中以塞莱希布组和配伍组对COX-2 mRNA表达的抑制作用最为明显,且配伍组作用明显强于黄芪组和莪术组,以罗格列酮组和配伍组对NF-KB mRNA的表达抑制作用和对PPARy表达的促表达作用都是最明显.结论:黄芪、莪术配伍能起到增效作用,对细胞的抑制效应明显,对COX-2的抑制作用大于黄芪、莪术的单独效应,与塞莱希布相近,其对COX-2的抑制作用可能是通过PPARy/NFKB信号途径发挥作用的. 相似文献
983.
Jiacong Luo Steven M. Brunelli Donna E. Jensen Alex Yang 《Clinical journal of the American Society of Nephrology》2016,11(1):90-100
Background and objectives
Patients with CKD are more likely than others to have abnormalities in serum potassium (K+). Aside from severe hyperkalemia, the clinical significance of K+ abnormalities is not known. We sought to examine the association of serum K+ with mortality and hospitalization rates within narrow eGFR strata to understand how the burden of hyperkalemia varies by CKD severity. Associations were examined between serum K+ and discontinuation of medications that block the renin-angiotensin-aldosterone system (RAAS), which are known to increase serum K+.Design, setting, participants, & measurements
A cohort of patients with CKD (eGFR<60 ml/min per 1.73 m2) with serum K+ data were studied (n=55,266) between January 1, 2009, and June 30, 2013 (study end). Serum K+, eGFR, and covariates were considered on a time-updated basis. Mortality, major adverse cardiovascular events (MACE), hospitalization, and discontinuation of RAAS blockers were considered per time at risk.Results
During the study, serum K+ levels of 5.5–5.9 and ≥6.0 mEq/L were most prevalent at lower eGFR: they were present, respectively, in 1.7% and 0.2% of patient-time for eGFR of 50–59 ml/min per 1.73 m2 versus 7.6% and 1.8% of patient-time for eGFR<30 ml/min per 1.73 m2. Serum K+ level <3.5 mEq/L was present in 1.2%–1.4% of patient-time across eGFR strata. The median follow-up time was 2.76 years. There was a U-shaped association between serum K+ and mortality; pooled adjusted incidence rate ratios were 3.05 (95% confidence interval, 2.53 to 3.68) and 3.31 (95% confidence interval, 2.52 to 4.34) for K+ levels <3.5 mEq/L and ≥6.0 mEq/L, respectively. Within eGFR strata, there were U-shaped associations of serum K+ with rates of MACE, hospitalization, and discontinuation of RAAS blockers.Conclusions
Both hyperkalemia and hypokalemia were independently associated with higher rates of death, MACE, hospitalization, and discontinuation of RAAS blockers in patients with CKD who were not undergoing dialysis. Future studies are needed to determine whether interventions targeted at maintaining normal serum K+ improve outcomes in this population. 相似文献984.
985.
心理社会因素在溃疡性结肠炎中的作用 总被引:1,自引:0,他引:1
目的:探讨心理社会因素在溃疡性结肠炎(UC)中的作用.方法:UC患者30例,正常对照组30例.采用明尼苏达多相人格调查表(MMPI)、汉米尔顿抑郁量表(HAMD)、汉米尔顿焦虑量表(HAMA)、生活事件量表(LES)、社会支持量表(ss)、多伦多述情障碍量表(TAS)对uC患者及正常人进行评定.结果:UC患者在Hs(t=4.39,P<0.01)、D(t=4.48,P<0.01)、Pt(t=2.67,P<0.05)、Sc(t=2.55,P<0.05)和HAMD(t=4.19,P<0.01)、HAMA(t=3.48,P<0.01)、TAS(t=3.81,P<0.01)量表的评分高于正常对照组. 结论:UC患者的人格因素及述情方式有明显异常. 相似文献
986.
Left stellate ganglion and vagal nerve activity and cardiac arrhythmias in ambulatory dogs with pacing-induced congestive heart failure. 总被引:2,自引:0,他引:2
Masahiro Ogawa Shengmei Zhou Alex Y Tan Juan Song Ghassan Gholmieh Michael C Fishbein Huai Luo Robert J Siegel Hrayr S Karagueuzian Lan S Chen Shien-Fong Lin Peng-Sheng Chen 《Journal of the American College of Cardiology》2007,50(4):335-343
OBJECTIVES: The purpose of this study was to determine the patterns of autonomic nerve activity in congestive heart failure (CHF). BACKGROUND: The relationship between autonomic nerve activity and cardiac arrhythmias in CHF is unclear. METHODS: We implanted radiotransmitters in 6 dogs for continuous (24/7) simultaneous monitoring of left stellate ganglion nerve activity (SGNA), vagal nerve activity (VNA), and electrocardiography before and after pacing-induced CHF. RESULTS: Congestive heart failure increased both SGNA and VNA. The SGNA but not VNA manifested a circadian variation pattern. There was extensive sinus node fibrosis. We analyzed 2,263 episodes of prolonged (>3 s) sinus pauses (PSP) and 1,420 long (>10 s) episodes of paroxysmal atrial tachycardia (PAT). Most (95.3%) PSP episodes occurred at night, and 56% were preceded by a short burst of SGNA that induced transient sinus tachycardia. Long PAT episodes were typically (83%) induced by simultaneous SGNA and VNA discharge, followed by VNA withdrawal. Premature ventricular contractions and ventricular tachycardia were preceded by elevated SGNA. CONCLUSIONS: The reduction of sympathovagal balance at night in ambulatory dogs was due to reduced sympathetic discharge rather than a net increase of vagal discharge. The tachybrady syndrome in CHF might be triggered by an intermittent short burst of SGNA that resulted in tachycardia and sinus node suppression. Simultaneous sympathovagal discharge is a cause of long PAT episodes. These data indicate that there is an association between the specific patterns of autonomic nerve discharges and cardiac arrhythmia during CHF. 相似文献
987.
988.
Martin TM Zhang G Luo J Jin L Doyle TM Rajska BM Coffman JE Smith JR Becker MD Mackensen F Khan MA Levinson RD Schumacher HR Wade NK Rosenbaum JT Reveille JD 《Arthritis and rheumatism》2005,52(1):269-274
OBJECTIVE: Uveitis or intraocular inflammation is a major cause of visual loss. Acute anterior uveitis (AAU) affects approximately 40% of patients with ankylosing spondylitis (AS) but also affects patients with no evidence of spondylarthritis. We sought to determine whether a unique genetic region could be implicated in a specific manifestation-AAU-of a multisystem, inflammatory, genetically complex disease, AS. METHODS: Individuals from families multiplex for AAU were genotyped at 400 markers representing the ABI PRISM linkage map MD-10, and at the HLA-B, DRB1, DQA1, DQB1, and DPB1 alleles. Among the family members with AAU, 76 affected sibpairs were analyzed (6 without concomitant AS, 12 discordant for AS, and 58 concordant for AS). Two-point and multipoint nonparametric linkage analyses were performed, and 1-parameter allele-sharing model logarithm of odds (LOD) scores were determined. RESULTS: As previously reported for AS, linkage at the major histocompatibility complex region (chromosome 6p21) was evident, exhibiting the highest multipoint LOD score (4.96 at marker HLA-B). Strong linkage was seen at a region on chromosome 9p21-9p24, with a LOD score of 3.72 at marker D9S157. When compared with a companion cohort of AS families, the linkage at this region was found in association with AAU but not with AS. A third region on chromosome 1q23-1q31 was observed to have suggestive linkage (LOD 2.05 at marker D1S238), which overlaps with a region associated with AS. CONCLUSION: This is the first study in which a genetic region for AAU has been identified by genome-wide scan. Even though AS was highly prevalent in this cohort of families, a locus at chromosome 9p21-9p24 was identified that uniquely associates with AAU. Identifying the genetic perturbation at this region may advance our understanding of the mechanisms involved in tissue-specific pathology of complex inflammatory diseases. 相似文献
989.
三种大鼠脂肪肝模型的比较 总被引:5,自引:0,他引:5
目的比较胃造瘘法、酒精灌胃法制作酒精性肝病及高脂营养饮食复制非酒精性肝病的三种动物模型制作方法和优缺点,为酒精性肝病的研究奠定更有效的模型基础.方法分别从胃造瘘管内注入56%白酒,至每次18 ml/kg·d,和经胃灌入同样白酒16~18 ml/kg·d,早、晚各1次,制作胃造瘘和酒精灌胃大鼠模型;又给刚断乳SD雄性大鼠喂养自制营养高脂饲料,复制肥胖性脂肪肝模型.实验开始后4、8、12、24周,在各实验组中随机取8只大鼠,心包腔穿刺取血,测肝功及血糖、血脂:并取小块肝组织分作光镜和电镜观察.结果酒精灌胃组大鼠总体死亡率较高,达37.9%.胃造瘘组仅16.0%,两组相比差异非常显著,P<0.01.营养性肥胖模型组大鼠体重增长迅速,至12周时已达434.6±30.4g,24周时达502.16±16.4g,分别明显高于对照组的356.9±31.4g和433.1±36.9g,T=4.3l,P<0.01.也明显高于另两组大鼠体重332.5±24.8g,412.5±34.4g和345.6±25.6g,430.6±26.9g,P<0.01.各模型组肝指数与相应之对照组比较,8周时始有显著差异,P<0.05;24周时差异更加显著,P<0.01.模型组血清肝功转氨酶较对照组显著升高,P<0.01;24周各模型组白蛋白明显下降,分别为28.04±2.42g/L,29.15±3.21g/L;28.56±193 g/L,与对照组相比有显著差异,P均<0.05.肥胖模型组TCH、TG显著高于对照组,P<0.01和P<0.05,血糖GLU与对照组相比无显著差异.各模型组8W时即可见脂肪肝的各种病理改变,12W时肝纤维化已明显形成.结论胃造瘘法克服了酒精灌胃模型的缺点,是适合我国国情的简便易行、经济可靠、死亡率低的酒精性肝病动物模型,值得推广应用. 相似文献
990.
血浆置换治疗重型肝炎42例 总被引:2,自引:0,他引:2
目的:探讨应用血浆置换治疗重型肝炎的临床疗效及不良反应.方法:我院住院的重型肝炎患者42例,在内科治疗效果不佳时,给予血浆置换治疗.观察患者三次治疗前后的临床症状、体征和肝肾功能、电解质、凝血功能的变化.结果:42例患者经血浆置换治疗后,临床症状及体征均有明显改善,肝功能有明显好转.三次治疗后与治疗前相比,ALB、CHE显著升高,而ALT、AST、ALP、GGT、TBA、TBIL明显下降,均有显著性差异,血NH3 第3次和第1次治疗前比较明显下降,有显著性差异(49.00±12.03 VS 69.96±34.87,P<0.05).血电解质变化不大,凝血功能有所改善,肾功能有轻微下降,但均无显著性差异.结论:应用血浆置换治疗重症肝炎,可以广泛迅速地清除肝衰竭患者体内的多种毒素,同时补充肝功能不全患者所缺乏的多种生物活性物质,改善机体内环境和肝功能,防治并发症,降低病死率,改善预后. 相似文献