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91.
PURPOSE: Methylenetetrahydrofolate reductase (MTHFR) is involved in the metabolism of folate and homocysteine; a polymorphism in the MTHFR gene (677C-->T) has been associated with adverse outcomes of pregnancy. We studied whether two polymorphisms in the MTHFR gene (677C-->T and 1298A-->C) are associated with pregnancy complications, adverse outcomes, and birth defects. METHODS: MTHFR polymorphisms were determined in blood collected in 1992 and 1993 from 5883 women aged 40 to 42 years, and linked with 14,492 pregnancies in the same women recorded in the Medical Birth Registry of Norway from 1967 to 1996. RESULTS: The 677TT genotype in mothers was associated with increased risk of placental abruption (odds ratio [OR] = 2.6; 95% confidence interval [CI]: 1.4 to 4.8) compared with the CC variant. The risk of intrauterine growth restriction increased with number of T alleles (P for trend = 0.04). Compared with the 1298AA variant, the CC variant was associated with a reduced risk of very low birth weight infants (OR = 0.4; 95% CI: 0.2 to 0.8). No significant associations were found between MTHFR polymorphisms and birth defects. CONCLUSION: The maternal MTHFR 677C-->T polymorphism was a risk factor for placental abruption. The unexpected protective effect of the 1298A-->C polymorphism on very low birth weight needs further study.  相似文献   
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Arnadottir IB, Holbrook WP, Eggertsson H, Gudmundsdottir H, Jonsson SH, Gudlaugsson JO, Saemundsson SR, Eliasson ST, Agustsdottir H. Prevalence of dental erosion in children: a national survey. Community Dent Oral Epidemiol 2010; 38: 521–526. © 2010 John Wiley & Sons A/S Abstract – Objectives:  To measure the prevalence of dental erosion in permanent teeth in Iceland as part of the National Oral Health Survey. Methods:  A representative, nationwide sample of 2251 Icelandic children, 20% of those aged 6, 12 and 15 year, was examined. Dental erosion was recorded for all erupted permanent teeth and graded using the modified scale of Lussi. Results:  Erosion was not seen in the permanent teeth of six‐year‐olds, but was present in 15.7% of 12‐year‐olds, more frequently in boys than girls (19.9% boys, 11.0% girls; P < 0.001). Among 15‐year‐olds, dental erosion was seen among 30.7% of subjects (38.3% boys, 22.7% girls; P < 0.001). Severity of erosion was mostly scored as grade I, with only 5.5% of 15‐year‐olds scored as grade II, mostly on tooth 46 (4.3%) and 36 (4.2%). For 12‐year‐olds, 0.9% had erosion scores of grade II mostly on tooth 46 (0.8%) and 36 (0.7%). No subjects had erosion of grade III. The most common clinical manifestation of erosion was the appearance of cup‐like lesions on the cusps of lower first molars. Conclusions: Dental erosion was frequently present by the age of 12; the prevalence doubled by age 15 and was seen almost twice as often among boys than girls. Teeth most frequently showing signs of erosion were the lower first molars. The rapidly growing prevalence of erosion demonstrated by this nationwide survey emphasizes the need for further research into the aetiology of erosion and possible methods of preventing and treating this emerging dental problem.  相似文献   
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Cytotoxicity of peritoneal dialysis fluids (PDF) not only results in cellular injury, but also induces heat-shock proteins (HSP), the main effectors of the cellular stress response. This study investigated effects of modulation of mesothelial HSP expression on peritoneal membrane integrity during acute PDF exposure. In the acute in vivo rat model of peritoneal dialysis (PD), either the HSP coinducer indomethacin or the HSP suppressor quercetin was added to standard PDF (CAPD 3, Fresenius, Germany). HSP-72 expression, number of detached mesothelial cells, and peritoneal protein loss were evaluated at the end of a 4-h dwell time. Compared with pure PDF exposure, addition of indomethacin resulted in increased expression of mesothelial HSP-72, reduced mesothelial cell exfoliation, and reduced peritoneal protein loss. Addition of quercetin resulted in decreased expression of HSP-72, increased mesothelial cell exfoliation, and higher peritoneal protein loss. Differences were statistically significant between indomethacin-treated and quercetin-treated rats. Mesothelial HSP expression was related to markers of peritoneal membrane integrity upon in vivo PDF exposure, consistent with HSP-mediated cytoprotection. These data clearly demonstrate the potential for clinically feasible pharmacologic interventions with the cellular stress response as a novel therapeutic approach to improve PD outcome.  相似文献   
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The effect of a combination of shock waves with cisplatin was examined in vivo with subcutaneously implanted amelanotic melanomas (A-Mel 3) in Syrian golden hamsters and cisplatin-sensitive or cisplatin-resistant fibrosarcoma (SSK2/0 and SSK2 R2) in C3H mice. In all 3 tumor models, 4 treatment modalities were compared: control, cisplatin treatment, shock waves and the combination of shock waves and cisplatin. Shock waves significantly delayed tumor growth in all 3 tumor models when compared to the respective control group. Cisplatin alone delayed the growth of A-Mel 3 and SSK2/0, whereas SSK2/R2 remained uninfluenced by the drug. In all 3 tumor models the combined treatment with shock waves and cisplatin additively and significantly delayed tumor growth. In A-Mel-3-bearing animals the combined treatment significantly increased survival time. The growth of SSK2/0 and SSK2/R2 tumors was delayed to a similar extent by the combined treatment modality as compared to shock-wave treatment alone. This indicates that the cisplatin resistance of SSK2/R2 tumors has been overcome by the simultaneous shock wave treatment. An increased intracellular cisplatin accumulation in the tumors due to shock wave exposure is suggested as the mechanism of interaction between shock waves and cisplatin.  相似文献   
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BACKGROUND: Ophthalmologic complications of endoscopic sinus surgery are rare, consequences may be serious. PATIENTS: Two patients are presented who suffered lesions of the internal rectus muscles during endoscopic ethmoidectomy. The clinical picture of this rare complication resembles that of a paralysis of the medial rectus muscle. THERAPY AND COURSE: In one patient the very thinned medial rectus muscle was tucked in a first surgical step. In the second step the external rectus muscle was recessed. Fusion in primary gaze was possible. In the second patient surgery was planned, he died however. CONCLUSION: Because of the anatomy the medial rectus muscle is endangered in endoscopic ethmoidectomy. Considered to the frequency of this surgery the incidence however is rare.  相似文献   
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