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1.
An association between juvenile xanthogranuloma (JXG), neurofibromatosis type 1 (NF1), and juvenile myelomonocytic leukemia (JMML) has been described in the literature but has only been documented in approximately 20 cases. We diagnosed a patient with NF1 at 25 months of age, before any cutaneous stigmata of this disease had appeared, because we decided to screen for the NF1 gene mutation because of his presentation with multiple JXGs and moderate macrocephaly (2.5 standard deviations) at 9 months of age and JMML diagnosed at 20 months of age. The child is well today after treatment with chemotherapy and allogenic bone marrow transplantation. With increased awareness, patients with JXG and NF1 who develop symptoms possibly related to JMML, such as paleness, skin bleeding, cough, unexplained fever, and hepatosplenomegaly, should be further evaluated. We also emphasize that multiple JXG lesions can be an early marker of NF1.  相似文献   
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ABSTRACT

Introduction: Steroid hormones are responsible for specific changes in the endometrium during the menstrual cycle, when they are sequentially secreted and, because of this, in the early days sequential combined oral contraceptive regimens were utilized. The same basic concept has been utilized with multi-phasic regimens, in order to produce endometrial pictures mimicking the normal cycle.

Areas covered: The Endometrial effects of progestins and estrogens; combined monophasic high- (50 μg), medium- (30 μg), low- (20 μg), ultralow- (15 μg) estrogen content; sequential regimens; multiphasic combinations; treatment schedules.

Cervical effects of combined high-dose and sequential combinations, including evidence for an increase in malignant lesions.

Expert opinion: Overall, combined oral contraceptives (COCs) inhibit normal proliferative changes and the endometrium becomes thin, narrow, with widely spaced glands and pre-decidual changes in the stroma. During the first few cycles the progestin induces a coexistence of proliferative and secretory features; with time, the picture changes because the progestin induces a down-regulation of estrogen receptors, resulting in tortuous glands similar to those in the secretory phase, but characterized by a quiescent, atrophic glandular epithelium.

In the cervical epithelium, under the influence of high-dose COCs, endocervical glands became hypersecretory and in some instances, distinctive type of atypical polypoid endocervical hyperplasia is found.  相似文献   
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Initially living donor liver transplantation (LDLT) was almost exclusively performed in infants and children. Adult LDLT programmes were initiated several years later. In the west this programme was introduced in view of a critical shortage of deceased donors and a constant increase in waiting list mortality. At present, this procedure is accepted as a therapeutic option for patients with end-stage liver disease to make up for the shortage of donor organs from dead patients. In Asia, however, LDLT has become the predominant means of liver transplantation as donor organs from the diseased cannot be used for religious and ethical reasons. Although there have been significant improvements in surgical techniques and consequently in recipient outcome over recent years, the LDLT procedure is still associated with donor morbidity and even mortality. The overall reported donor mortality was 0.2% and donor morbidity ranged between 0% and 100%. Biliary complications and infections were the most commonly reported donor complications. Therefore, a thorough medical as well as psychological evaluation of the donor and recipient are necessary prior to this procedure. To date, LDLT comprises less than 5% of adult liver transplantations in Europe and in the United States. Recipient and graft survival are almost identical to those seen with liver transplantations from deceased donors (DD). Biliary and vascular complications are more often seen in the LDLT setting. So far, no studies have focussed on the impact of LDLT on waiting list mortality. There is international consensus that this procedure should be restricted to centres with large experience in deceased donor liver transplantations as well as in hepatobiliary surgery. Ethical issues, optimal utility and application of adult LDLT and optimal recipient and donor characteristics have yet to be defined.  相似文献   
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Summary:  Naturally occurring mutants and genetically manipulated strains of mice are widely used to model a variety of human diseases. Atlases are an invaluable aid in understanding the impact of such manipulations by providing a standard for comparison and to facilitate the integration of anatomic, genetic, and physiologic observations from multiple subjects and experiments. We have developed digital atlases of the C57BL/6J mouse brain (adult and neonate) as comprehensive frameworks for storing and accessing the myriad types of information about the mouse brain. Along with raw and annotated images, these contain database management systems and a set of tools for comparing information from different techniques and different animals. Each atlas establishes a canonical representation of the mouse brain and provides the tools for the manipulation and analysis of new data. We describe both these atlases and discuss how they may be put to use in organizing and analyzing data from mouse models of epilepsy.  相似文献   
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OBJECTIVE: To identify the surgical approaches and risk factors which influence longevity of right ventricle to pulmonary artery (RV-PA) conduits following first reoperation for obstruction. METHODS: Between January 1993 and August 2003, 114 patients underwent 141 reoperations for RV-PA conduit obstruction. Diagnoses included 'Truncus Arteriosus' (n=52), 'Pulmonary atresia/Tetralogy of fallot' (n=39), 'Double outlet right ventricle' (n=10), 'Transposition of great arteries, VSD, and pulmonary atresia' (n=9), and the 'Ross operation' (n=4). All patients had undergone a previous biventricular repair. The first reoperation for conduit obstruction was performed in 112 hospital survivors by: total conduit replacement (Group A, n=73) with valved (homograft=10 and xenograft=54) or non-valved (n=9) conduit, and patch enlargement of the obstructed RV outflow tract with preservation of the posterior and sides of the conduit wall after removing of the fibrocalcific peel and degenerated valve (Group B, n=39). Mean age at first reoperation was 8.8+/-6.7 and 7.5+/-5.3 years in patients of groups A and B, respectively. Seven patients in Group A and 18 in Group B required a second reoperation and two patients in Group B a third reoperation. RESULTS: There were two hospital deaths and no late deaths. Mean follow-up was 5.8+/-3.2 years. Risk factors for second reoperation by univariate analysis were: homograft conduit use (P=0.004), Group B surgical approach (P=0.0001), higher RV-PA systolic pressure gradient at discharge (P=0.02), and age <5-years-old (P=0.01). Multivariate analysis showed that inclusion in Group B and younger age (<5-years-old) at repair were independent risk factors for second reoperation. Group B surgical approaches had higher RV-PA systolic pressure gradient at discharge (P=0.02) and required more PA bifurcation repair at the time of second reoperation (P=0.05). Freedom from second reoperation for conduit obstruction was significantly higher in Group A patients at 5 and 8 years (P<0.04) and those with xenografts rather than homograft (P=0.04). CONCLUSIONS: Our results support the optimal surgical approach for RV-PA conduit obstruction is total replacement with a xenograft. RV outflow reconstruction by other techniques without complete dissection of PA bifurcation does not completely relieve the stenosis and could cause early restenosis. Higher systolic gradients at discharge and younger age at first reoperation are predictors of earlier reoperation.  相似文献   
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AIM: To determine the 2-year efficacy of continuous subcutaneous insulin infusion (CSII) following the current established criteria for funding of a National Health Service. METHODS: Longitudinal, prospective, observational unicentre study. Included in the study were 153 Type 1 diabetes (T1D) subjects, previously treated with multiple daily injections (MDI) of insulin, in whom CSII was started in accordance with the criteria for reimbursement of the Catalan National Health Service. At baseline, we recorded data on age, gender, duration of the disease, body mass index (BMI), insulin dose and indications for CSII. Glycated haemoglobin (HbA(1c)) and the frequency of hypoglycaemic events were used to assess glycaemic control. Quality of life was assessed using three different self-report questionnaires. After 24 months, these same items were remeasured in all subjects. Serious adverse events and injection-site complications were also recorded. RESULTS: In 96% of subjects, CSII indication included less than optimal glycaemic control using MDI. HbA(1c) fell from 7.9 +/- 1.3 to 7.3 +/- 1.1% (P < or = 0.001) after 24 months of CSII. Insulin requirements were significantly lower at the end of follow-up (0.55 +/- 0.21 U/kg body weight) in comparison with before use of CSII (0.70 +/- 0.20, P < or = 0.001). BMI increased from 24.0 +/- 3.1 to 24.4 +/- 3.2 kg/m(2) after 24 months (P < or = 0.025). The rate of episodes of diabetic ketoacidosis per year remained unchanged. Mild and severe hypoglycaemic episodes were significantly reduced. The scores in all subsets of the Diabetes Quality-of-Life (DQoL) questionnaire significantly improved after 24 months of CSII. CONCLUSIONS: CSII, commenced according to the criteria for a nationally funded clinical programme, improves glycaemic control and quality-of-life outcomes with fewer hypoglycaemic episodes in T1D subjects previously conventionally treated with MDI.  相似文献   
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