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Background  

At present, there is no conclusive evidence regarding the best treatment method for reducible unstable fractures of the distal radius. This study compared the effectiveness of two methods used in surgical treatment of such fractures: percutaneous pinning and external fixation.  相似文献   
613.

Background  

Home ultraviolet B (UVB) treatment is a much-debated treatment, especially with regard to effectiveness, safety and side effects. However, it is increasingly being prescribed, especially in the Netherlands. Despite ongoing discussions, no randomised research has been performed, and only two studies actually compare two groups of patients. Thus, firm evidence to support or discourage the use of home UVB phototherapy has not yet been obtained. This is the goal of the present study, the PLUTO study (Dutch acronym for "national trial on home UVB phototherapy for psoriasis").  相似文献   
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We hypothesized that placental resistance was elevated and transfer reduced in cotyledons from intrauterine growth-restricted (IUGR) fetuses. We perfused 10 cotyledons from term, normally grown fetuses, six from preterm, normally grown fetuses with normal umbilical arterial end-diastolic velocities (EDV), and six from preterm IUGR fetuses (<3rd centile) with absent or reversed umbilical arterial EDV. Perfused cotyledons were pressure-fixed, and villi were observed by scanning electron microscopy. The groups did not differ in fetoplacental resistance at baseline; neither did they differ in the change in resistance that followed the administration of nitroglycerin or angiotensin II. The increase in resistance during hypoxia was similar in the two preterm groups but greater in the term than in the preterm normally grown group (p < 0.05). Groups did not differ in net maternofetal transfer of oxygen or glucose, or in clearance of aminoisobutyric acid or antipyrine. However, glucose consumption was doubled in cotyledons of preterm IUGR versus preterm normally grown fetuses (p < 0.05). Terminal villi of perfused cotyledons from preterm IUGR fetuses displayed less terminal villous branching and budding than preterm controls, as anticipated from previous work. IUGR fetuses with absent or reversed umbilical arterial EDV in vivo may have high placental resistance due to a vasoconstrictive rather than anatomic abnormality and an elevated placental glucose consumption that may impair glucose transfer.  相似文献   
616.
High resolution electrocardiography (HRECG) recordings have already shown an increased beat-to-beat microvariability of the QRS duration of the terminal QRS in patients with a history of ventricular tachycardia (VT). The purpose of this study is to detect QRS-duration microvariability with magnetocardiographic (MCG) recordings in normals, patients with coronary heart disease (CHD), patients with a history of myocardial infarction (MI), and VT patients. QRS microvariability is calculated as the variance of time-shifts of single beats respectively to the average of all beats. The average over all channels of the MCG is performed. QRS microvariability was evaluated from 55-channel MCG in 15 normal persons, in 12 patients with CHD, in 13 patients with MI, and in 10 patients with VT. We found a significantly higher microvariability in patients with MI compared to normals. The highest microvariability was found in VT patients.  相似文献   
617.
King AE  Kelly RW  Sallenave JM  Bocking AD  Challis JR 《Placenta》2007,28(11-12):1099-1106
The prevention of uterine infection is critical to appropriate fetal development and term delivery. The innate immune system is one component of the uterine environment and has a role in prevention of uterine infection. Natural antimicrobials are innate immune molecules with anti-bacterial, anti-viral and anti-fungal activity. We discuss two groups of natural antimicrobials in relation to pregnancy: (i) the defensins; and (ii) the whey acidic protein motif containing proteins, secretory leukocyte protease inhibitor (SLPI) and elafin. Human beta-defensins (HBD) 1-3 are expressed by placental and chorion trophoblast, amnion epithelium and decidua in term and preterm pregnancy. Elafin shows a similar pattern of localisation while SLPI is produced only by amnion epithelium and decidua. Evidence suggests that there is aberrant production of some natural antimicrobials in pathologic conditions of pregnancy. In preterm premature rupture of membranes (PPROM) levels of SLPI and elafin are reduced in amniotic fluid and fetal membranes, respectively. Elafin and HBD3 increase in chorioamnionitis and levels of the alpha-defensins, HNP1-3, increase in maternal plasma and amniotic fluid in women affected by microbial invasion of the uterus. In vitro culture studies have suggested a mechanism for increased production of natural antimicrobials in chorioamnionitis. Elafin, SLPI, HBD2 and 3 are all upregulated by inflammatory molecules in cells derived from gestational tissues. In summary, production of natural antimicrobials at key sites within the pregnant uterus suggests an important role in prevention of uterine infection during pregnancy and labour. Aberrant production of these molecules in PPROM and chorioamnionitis suggests that they also have a role in pathologic conditions. In particular, upregulation of these molecules by inflammatory molecules present in chorioamnionitis will ensure a robust response to infection.  相似文献   
618.
Prostaglandins play a central role in the stimulation and maintenance of both term and preterm labor. 15-Hydroxyprostaglandin dehydrogenase (PGDH), localized primarily to chorion trophoblasts, is the key enzyme responsible for the metabolism of prostaglandins. In preterm chorion, levels of PGDH protein and activity were lower when compared to term and were further reduced with the presence of infection, but effects of subclinical inflammation and membrane rupture on PGDH expression are not known. Our objectives were (1) to determine the relative expression of PGDH in amnion and chorion and (2) to determine the effect of preterm premature rupture of membranes (PPROM) and (3) subclinical inflammation on PGDH protein expression in preterm fetal membranes. Fetal membranes were collected from women with idiopathic preterm labor. Patients were divided into preterm birth (1) <32 weeks with PPROM (n = 6), (2) <32 weeks with intact membranes (n = 11), (3) >or=32 and <37 weeks with PPROM (n = 10), and (4) >or=32 and <37 weeks with intact membranes (n = 10). Different antibodies were used to detect protein expression and localization of PGDH in amnion and chorion from these patients using both Western blotting and immunohistochemistry. Antibody T (AbT) localized PGDH to chorion trophoblasts, whereas antibody C (AbC) detected immunoreactive (ir) PGDH predominantly in the amnion mesenchyme. By Western blot, AbT showed a stronger 29-kDa ir-PGDH band whereas with AbC, a stronger 55-kDa ir-PGDH signal was detected. 55-kDa ir-PGDH was significantly higher in PPROM amnion, specifically in the <32 weeks group (P < .05) and with PPROM >24 hours (P < .05). No change was detected in the 29-kDa ir-PGDH in either amnion or chorion with gestational age or the presence and absence of PPROM. In addition, neither form of ir-PGDH was altered significantly with or without subclinical inflammation. ir-PGDH is detectable in both chorion trophoblasts and amnion, especially in the mesenchyme; however, the predominant form of the enzyme differs in the 2 tissues. PPROM and subclinical inflammation do not appear to affect the levels of 29-kDa ir-PGDH protein in the fetal membranes. The differential expression of 55-kDa ir-PGDH in preterm amnion with and without PPROM supports the need for a better understanding of the different forms of PGDH.  相似文献   
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德国研究者在前期研究基础上通过体外培养和免疫干预一类巨噬细胞获取移植耐受诱导细胞(transplant acceptance—inducing cells,TAICs),并在前期动物实验中证实应用TAICs可以在一定程度上特异性减轻排斥反应,使移植受者可以安全地减少传统免疫抑制剂用量。本文主要介绍了TAICs的临床制备方法及其在尸体肾移植受者中的应用情况。首先,临床可用的TAICs制备方法主要是采用尸体供肾者的脾脏分离单个核细胞,并通过5d的分阶段的TAICs培养基的培养制备出TAICs,其主要表型仍保持巨噬细胞亚型的特征,  相似文献   
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