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In some autosomal imbalance syndromes an additional imbalance interferes with the occurrence of the anomalies typical of the syndrome itself. For example, polydactyly was found in patients with “pure” del(3p) more frequently (11/23) than in patients where these deletions were associated with different partial trisomies (2/28). The opposite situation was shown in del(7q) syndrome where various defects of the holoprosencephalic group were found to be rarer in patients with “pure” deletions, than in cases with simultaneous occurrence of various partial trisomies. It suggests the importance of gene interaction in determining the phenotypic picture of autosomal imbalance syndromes. © 1993 Wiley-Liss, Inc.  相似文献   
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Six familial cases of the Beemer–Langer syndrome (BLS) were analyzed to further elucidate the spectrum and frequency of anomalies observed in this disorder. Preaxial polydactyly was found in 3/6 affected sibs, and, therefore, its frequency previously may have been underestimated. Some patients, described as infants affected with the Majewski syndrome (MS) or “atypical” short rib-poly-dactyly conditions, may indeed have BLS. A high frequency of brain defects (16/26) and cleft tongue, oral frenula, and/or natal teeth (13/29) widens the list of typical findings in this syndrome. The specific type of tibial defect seems to be the most important discrimination of the MS and the BLS. © 1994 Wiley-Liss, Inc.  相似文献   
5.
Leptin is an adipocyte-secreted hormone which plays a key role in energy homeostasis. Recent “proof of concept” studies involving leptin administration to humans support its critical role in regulating energy homeostasis, neuroendocrine and immune function as well as insulin resistance in states of energy/ caloric deprivation. Moreover, interventional studies in leptin deficient children and observational studies in normal girls and boys support a role for leptin as a permissive factor for the initiation of puberty in children. The potential clinical usefulness of leptin in several disease states in children and adolescents, including hypothalamic amenorrhea, eating disorders and syndromes of insulin resistance is still under investigation.  相似文献   
6.
OBJECTIVES: The aim of study was to estimate the probability rates for unfavorable pregnancy outcomes in carriers of reciprocal chromosomal translocations involving 13 chromosome (RCT-13q). MATERIAL AND METHODS: We collected total empirical data about 232 pregnancies of 56 carriers coming from 28 pedigrees. RCT classification was based on classic cytogenetic methods for interpretation of breakpoint position. The probability rates of particular type of pathology related to the total number of pregnancies after ascertainment correction have been calculated with the help of Stengel-Rutkowski and Stene method. RESULTS: The risk figures for unbalanced offspring after 2:2 disjunction and adjacent-1 segregation for the whole group of pedigrees were calculated as 5.2 +/- 1.7% (9/173)--medium risk, for maternal (MAT) and paternal (PAT) carriers were about 6.2 +/- 2.3% (7/173) and 4.8 +/- 3.3% (2/42) respectively. Considering different segment lengths of 13q, similar values for shorter and longer segments were obtained [4.3 +/- 1.9% (5/115) for 13q21-->qter and 7.0 +/- 3.3% (4/58) for 13q12-->qter]. The risk figures for miscarriages as 36.4 +/-3.6% (63/173) and for stillbirths/early death as 4.6 +/- 31.6% (8/173) were obtained. The risk figures for unbalanced offspring after 3:1 disjunction were calculated as 7.7 +/- 7.45 (9/13). Conclusions: 1. Risk figures for different pregnancy outcomes are differ among particular forms of pathology. 2. Probability rate for unbalanced progeny at birth was calculated as a medium risk and similar values for carriers of different segments of 13q were obtained. 3. Probability rate for miscarriages was high but risk for stillbirths/early deaths of newborn was low. 4. No differences in values of rate for particular forms of pathology were found for maternal and paternal carriers of RCT-13q.  相似文献   
7.
Background Intractable reflux, either due to gastric prolapse or concentric pouch dilatation has been the most common indication for reoperation or band removal after laparoscopic adjustable gastric banding (LAGB). We have previously found that a simple hiatal hernia repair (HHR) leads to remission of these symptoms minimizing the need for band removal. We have subsequently added crural repair/HHR at the initial operation, where indicated. In this study compare the rate of reoperation in patients who underwent LAGB alone, or with concurrent HHR. Methods A retrospective review of a prospective database of all patients undergoing LAGB was performed to determine the incidence of reoperation in the two groups. Results Between July 2001 and August of 2006, 1298 patients underwent LAGB and 520 patients underwent LAGB with concurrent HHR (LAGB/HHR). The mean initial weight and BMI were 128 kg (range, 71.1–245.7 kg) and 45.4 kg/m2 (range, 28–75 kg/m2). Average follow-up for the LAGB and LAGB/HHR groups was 24.8 and 20.5 months, respectively. Rate of reoperation for HHR alone, or with band slip or concentric pouch dilatation, for LAGB and LAGB/HHR groups was 5.6% and 1.7% respectively (p < 0.001). Total reoperation rate for slip, HHR and pouch dilatation was 7.9% and 3.5%, respectively (p < 0.001). There was no significant difference in rate of slip repair alone between the two groups: 2.3% and 1.7%, respectively (p < 0.44). Conclusions Adding HHR to LAGB where indicated significantly reduces reoperation rate. Every effort should be made to detect and repair HHR during placement of the band, as it will decrease future need for reoperation.  相似文献   
8.
In patients who require lower extremity revascularization, prosthetic graft is a reasonable alternative in the absence of a suitable autologous vein conduit. However, prosthetic bypass grafts have limited patency, especially for infrageniculate reconstruction. Polytetrafluoroethylene grafts were geometrically modified at the distal end to increase their patency. The authors reviewed their experience with the Distaflo graft in patients who required lower extremity below-knee popliteal and tibial bypasses when no suitable autologous vein conduit was available. Chart review was conducted of the 57 patients who underwent 60 lower extremity bypasses over a 3-year period between June 2003 and April 2006. Twenty-four revascularizations were constructed to the tibial outflow sites, whereas the remaining grafts were placed to the below-knee (28) and above-knee (8) popliteal artery, respectively. Study endpoints were primary, assisted primary, secondary patency, and limb salvage at the time of follow-up. Distaflo bypass was performed at the infrageniculate level in 86.7% of cases (28 below-knee popliteal, 24 tibial). Mean follow-up time was 12 months (range, 0.5-37.5 months). At 1 year, primary, assisted primary, and secondary patencies and limb salvage rates for below-knee popliteal bypasses were 83.5%, 89.5%, 94.7%, and 94.4%, respectively. Primary, assisted primary, and secondary patencies and limb salvage rates for tibial bypasses were 44.4%, 44.4%, 63.2%, and 74.9%, respectively. Distaflo precuffed graft is a good alternative conduit for below-knee popliteal and tibial lower extremity reconstructions in the absence of an autologous vein and appears to have promising early patency and limb salvage rates even when used for tibial bypasses.  相似文献   
9.
G Iosif  J Fleischman  R Chitkara 《Chest》1991,99(6):1538-1539
Empyema developing seven weeks after craniotomy in a 62-year-old black woman with an ipsilateral ventriculopleural (V-PL) shunt is described. Infection of the pleural space presumably resulted from transfer of organisms from a proximal V-PL shunt infection to the thorax. Empyema resulting from V-PL shunt infection has not previously been reported. Pleural effusions in patients with V-PL shunts must be considered as a potential site of infection with possible development of empyema.  相似文献   
10.
ABSTRACT

Objective: The purpose of this study was to assess enamel gloss changes induced by orthodontic bracket bonding with a light-cured composite or a light-cured resin-reinforced glass ionomer cement.

Setting: The Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, Greece.

Design: Laboratory study.

Methods: A total of twenty extracted upper human first premolars were included in this study and each tooth served as a control for itself. Their buccal surfaces were subjected to 60o-angle gloss measurement (G%60) with a standardized and secure repeated analysis of the same site. After baseline evaluation, a bracket was bonded on the buccal surface of each tooth. Half of the specimens were bonded with acid-etching and a light-cured composite whereas the other half with a light-cured resin-reinforced glass ionomer cement without prior enamel conditioning. Gloss measurements were repeated after bracket debonding and removal of the composite/glass ionomer cement with an 18-fluted carbide bur. Gloss differences between the two measurement conditions (baseline and post-debonding) were analyzed through linear regression with standard errors derived using the bootstrap method. Level of significance was set at a?<?0.05.

Results: A statistically significant difference was detected between the tested groups for the outcome of interest. Teeth bonded with light-cured composite exhibited larger enamel gloss changes as compared to resin-reinforced glass ionomer cement (β?=?0.74; 95% CIs: 0.10, 1.38; p?=?0.02).

Conclusions: Bracket bonding with two common bonding protocols (acid-etching with a light-cured composite vs. no etching with resin reinforced glass-ionomer cement) and subsequently debonding and adhesive removal with an 18-fluted carbide bur induced enamel gloss changes.  相似文献   
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