Dynamax和Twin block矫治器治疗安氏Ⅱ类Ⅰ分类错牙合疗效比较

目的 评价Dynamax和 Twin block 两种功能矫治器治疗安氏Ⅱ类 1 分类下颌后缩患者前后软硬组织的改变.方法 选择 Hagg 手腕骨片为 FG-G 期的安氏Ⅱ类1分类下颌后缩患者30例,随机分为两组分别接受Dynamax和Twin block治疗,应用X线头影测量技术进行治疗前后的22项软硬组织分析.结果 GoGnSN(°)、Cm-Sn-Ls(°) 、S-Ns- Si (°)的变化的差异有统计学意义(P<0.05),余无统计学意义.结论 Dynamax或Twin block功能矫治器早期治疗安氏Ⅱ类1分类下颌后缩患者,其软硬组织疗效基本一致.但同twin-block组比较,Dynamax组下颌平面角增大,且Dynamax更适合于同时进行固定矫治治疗.     

Micropropagation of Tigridia pavonia (L.f) DC-a potential floricultural plant from twin scale explants

ObjectiveThe present study was performed to standardize an effective protocol for micropropagation of Tigridia pavonia using tissue culture.MethodsThe explants were cultured on Murashige and Skoog (MS) medium supplemented with cytokinins like thidiazuron (TDZ), zeatin, kinetin and auxins such as indole-3-acetic acid (IAA), 1-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA), individually at different concentrations.ResultsMultiple shoots were obtained on MS medium containing either 2.0 mg/L TDZ or 2.0 mg/L IAA or 0.5 mg/L IBA and in the same medium for a long period (120 d) produced tiny bulbs at the base of the senescent leaves. TDZ favored only multiple shoots without roots, whereas IAA or IBA individually or in combination with TDZ produced rooted shoots. Shoots developed on MS medium supplemented with TDZ were rooted on MS medium containing either IBA or NAA at 0.5 mg/L. The plantlets were acclimatized in pots containing garden soil. Regenerated plantlets developed into normal plants. The plants showed 99% survival.ConclusionsThe highest number of bulblets obtained in the present study represents an effective alternative to the conventional method.     

Vaginal Delivery of a Second,Nonvertex Twin by High Vacuum After Failed Breech Extraction and Successful External Version

Several options exist to effect vaginal delivery of a second, nonvertex twin. In the case presented, breech extraction and external version with subsequent labor were both inadequate to achieve timely delivery before the onset of fetal distress. A case of vacuum extraction of an unengaged second twin converted to vertex is described and discussed.     

Sonographic Measurement of Umbilical Vein and Umbilical Cord Diameters in Normal and Diabetic Pregnancies

Sonographic visualization of umbilical cord components is becoming increasingly important in evaluating fetal well-being. Standard graphs of umbilical vein and cord measurements during the last two trimesters of 219 normal singleton pregnancies showed a linear increase in transverse dimensions with advancing gestational age. Preliminary data on 38 pregnancies complicated by maternal diabetes mellitus, showed significant deviations from normal umbilical measurements.     

Three Cases with Cavitary Lesions in a Twin Gestation Complicated by a Single Intrauterine Fetal Demise

Three cases with cavitary lesions on the cerebral convexities in twin gestation complicated by a single intrauterine fetal demise were investigated clinicopathologically. They all exhibited profound mental retardation and severe motor disturbance due to rigidospastic tetraplegia. The co-twins were macerated. Neuropathologically, malformed lesions and destructive lesions coexisted in varying degrees according to the time in fetal life, at which insults probably occurred. The cavitary lesions were located bilaterally and symmetrically on the central, parietal and occipital region of the cerebral hemispheres, in some cases, including the frontal region. Case 1 showed an incomplete gyral pattern and porencephaly with polymicrogyria bordering the defect, thus allowing us to date the insult before the 5th fetal month. In case 2, multicystic encephalomalacia was disclosed with cortical dysgenesis exhibiting status marmoratus of the cortex. Case 3 displayed sclerotic cavitary lesions with sclerosis of the insula and a few instances of cortical dysgenesis. Based on the clinical data and pathological findings, the cavitary lesions of case3 may be dated in the third trimester of gestation. Case 2 can be considered to have sustained injuries between the times estimated for cases 1 and 3. As the pathogenesis of the congenital cavitary lesions, several concepts have been proposed: intrauterine DIC (Moore et al. 1969;Romero et al. 1984), vascular disruption (Hoyme et al. 1981;Jung et al. 1984), intrauterine infection such as cytomegalic inclusion disease (Friede et al. 1976), and hypoxia due to CO intoxication of the mother (Bank1 et al. 1967) or other cause. Though the pathological observation of our cases revealed no evidence of intrauterine DIC, renal cortic necrosis, intrauterine infection or occlusion of the intracranial vessels, long-term exposure to the dead twin might have contributed to the lesions of the liveborn co-twin.     

The number of pregnancies is a risk factor for Alzheimer's disease

Epidemiological data show a higher prevalence of late-onset Alzheimer's disease (AD) in women. The estrogenic deficiency in the post-menopausal period is suspected to be the cause of the gender-related risk of the disease, but studies on the estrogenic therapy and occurrence of AD were not consistent and sometimes contradicting. The aim of this study is to investigate whether a higher exposure to endogenous estrogens is associated with lower risk of dementia or not. Two hundred and four AD patients and 201 control women were considered. By interviews, we evaluated different variables, indirectly correlated to estrogenic natural exposure, as well as educational level and head trauma. These data were correlated in the AD group with the disease progression, as well as with the age at onset. Unexpectedly, we found a significant higher number of pregnancies in the AD than in the control group. Within the AD cases, the number of lifetime pregnancies is related to an earlier onset of the disease. As previously reported, we confirmed that the educational level is a protective factor and that major head trauma represents a risk factor in developing AD. The higher number of pregnancies and a less frequency of nulliparous women, indirectly relate the AD group to a higher estro-progestinic exposure. These findings suggest that it is the increase of progesterone or estrogens level – and not the estrogens decrease, as previously indicated by other authors – that could play a role in the Alzheimer's pathology.     

El Registro de Gemelos de Murcia. Un recurso para la investigación sobre conductas relacionadas con la salud

Genetically informative designs and, in particular, twin studies, are the most widely used methodology to analyse the relative contribution of genetic and environmental factors to inter-individual variability. These studies basically compare the degree of phenotypical similarity between monozygotic and dizygotic twin pairs. In addition to the traditional estimate of heritability, this kind of registry enables a wide variety of analyses which are unique due to the characteristics of the sample. The Murcia Twin Registry is population-based and focused on the analysis of health-related behaviour. The observed prevalence of health problems is comparable to that of other regional and national reference samples, which guarantees its representativeness. Overall, the characteristics of the Registry facilitate developing various types of research as well as genetically informative designs, and collaboration with different initiatives and consortia.     

Genetic influences on mannan-binding lectin (MBL) and mannan-binding lectin associated serine protease-2 (MASP-2) activity

The lectin pathway of the complement system is activated when Mannan-binding lectin (MBL) in complex with MASP-2 binds microorganisms. Polymorphisms in both genes are responsible for low serum levels, which associate with increased risk of infection and autoimmune disease. The present study includes 1215 MBL measurements and 1214 MASP-2 activity measurements in healthy Danish adult twins. Total MASP-2 activity was estimated by C4 cleaving activity of samples diluted in an excess of MBL. Twin-twin correlations were higher in monozygotic (MZ) than in dizygotic (DZ) twins for both traits. Heritabilites of MBL levels and MASP-2 activity were estimated using structural equation modeling allowing assessment of the contribution of common genes affecting both traits. The estimated heritability was 0.77 [95% CI 0.64;0.91] for MBL levels and 0.75 [95% CI 0.59;0.81] for MASP-2 activity with the presence of additive genetic factors, shared environmental factors, and non-shared environmental factors. The genetic correlation, i.e., common genetic factors affecting MBL and MASP-2 activity was estimated to r(g) = 0.34 [0.25;0.42]. The data indicate a strong genetic influence for the serum levels of MBL and for MASP-2 activity with a significant genetic correlation between the two traits.     

双胎合并肝内胆汁淤积症围生儿预后分析

目的 :分析双胎妊娠合并胆汁淤积症围生儿预后。方法 :对 1999年 1月～ 2 0 0 0年 12月在我院住院的 2 1例双胎妊娠合并胆汁淤积症 (ICP)临床资料进行回顾性分析 ,与同期双胎非ICP进行比较。结果 :(1)双胎ICP的胎儿宫内窘迫发生率、新生儿重度窒息率及围生儿病死率均比双胎非ICP显著增加。 (2 )在双胎ICP组 ,死亡围生儿平均孕周比对照组显著延长 ,平均体重亦显著重于对照组。结论 :早期诊断 ,加强监护和及时终止妊娠是降低双胎ICP围生儿死亡率的主要措施     

Large Subchorionic Hematoma: Breus' Mole

A case of large subchorionic hematoma complicated by intrauterine growth retardation and oligohydramnios diagnosed at 32 weeks' gestation with twin pregnancy after ICSI is reported below. The patient was on clexane injection during pregnancy for mitral valve replacement. She was managed with tocolysis using progesterone therapy and antibiotic with followup until delivery. At 34 weeks, a male baby weighing was delivered without complication by caesarean section because of single fetal demise of twin pregnancy.