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91.
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N-cadherin is a classical type I cadherin that contributes to the formation of neural circuits by regulating growth cone migration and the formation of synaptic contacts. This study analyzed the role of N-cadherin in primary motor axons growth during development of the zebrafish (Danio rerio) embryo. After exiting the spinal cord, primary motor axons migrate ventrally through a common pathway and form the first neuromuscular junction with the muscle pioneer cells located at the horizontal myoseptum, which serves as a choice point for cell-type-specific pathway selection. Analysis of N-cadherin mutants (cdh2(hi3644Tg) ) and embryos injected with N-cadherin antisense morpholinos showed primary motor axons extending aberrant axonal branches at the choice point in ~40% of the somitic hemisegments and an ~150% increase in the number of branches per axon length within the ventral myotome. Analysis of individual axons trajectories showed that the caudal (CaP) and rostral (RoP) motor neurons axons formed aberrant branches at the choice point that abnormally extended in the rostrocaudal axis and ventrally to the horizontal myoseptum. Expression of a dominant-interfering N-cadherin cytoplasmic domain in primary motor neurons caused some axons to stall abnormally at the horizontal myoseptum and to impair their migration into the ventral myotome. However, in N-cadherin-depleted embryos, the majority of primary motor axons innervated their appropriate myotomal territories, indicating that N-cadherin regulates motor axon growth and branching without severely affecting the mechanisms that control axonal target selection.  相似文献   
94.

Purpose

We present five cases of adult females with major limb amputations, their concerns and preferences for services across the life span.

Design

A convenience sample of five veteran and nonveteran women aged 19–58 with major limb amputations participating in a regional VA Prosthetics Conference in 2010 took part in a panel interview.

Findings

The concerns identified by these women as high priorities included independence and participation in a full range of life activities, limitations in access, patient decision‐making and body image concerns, and preferences for selected services. Maximizing function and quality of life for women amputees requires identifying patient preferences for rehabilitation and prosthetic services. Lessons learned could inform development of clinic‐based rehabilitation care, prosthetic services, and studies of women with major limb amputations.

Conclusions

As the current conflicts in Iraq and Afghanistan wind down, the number of women veterans seeking rehabilitation and prosthetic services will increase. With this information, rehabilitation and prosthetic service providers and organizations will be uniquely positioned to provide prevention and treatment of amputations for this growing population of women veterans in national care delivery systems and in communities.

Clinical Relevance

An open‐ended facilitated discussion among a panel of women with major limb amputations provided insights for providers and organizations with respect to needs, concerns, and preferences for rehabilitation and prosthetic services.  相似文献   
95.
最近,加拿大建筑师提出新的设计理念:从患者的需要出发规划建筑,把医院重塑为治疗和社交的场所。由此产生了这样的模式——所有传统的医疗部门包括医生办公室、急症部门和手术室将与健康饮食中心,健身中心和疾病管理部门建在同一区域内。  相似文献   
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97.
It is well established that low level Pb-exposure is associated with a wide range of cognitive and neurobehavioral dysfunctions in children. In fact, Pb-induced damage occurs preferentially in the prefrontal cerebral cortex, hippocampus and cerebellum - the anatomical sites which are crucial in modulating emotional response, memory and learning. Previously it was also shown that nitric oxide (NO) signaling pathway as well as glutamatergic neurotransmission are both involved in brain development, neurotoxicity and neurodegeneration processes whereas Pb(2+) interfere with both. For this reason we investigated the effect of ontogenetic Pb(2+) exposure on dopaminergic neurotransmission in the medial prefrontal cortex (mPFC) of rats after amphetamine (AMPH) and/or 7-nitroindazole (7-NI) administration. Furthermore, the possible role of oxidative stress in Pb(2+)-induced neurotoxicity in prenatally Pb(2+)-treated rats was explored in the content of hydroxyl radical (HO(*)) species in mPFC after AMPH and/or 7-NI injection, assessed by HPLC analysis of 2.3-dihydroxybenzoic acid (2.3-DHBA) - spin trap product of salicylate. As shown, the results of this study suggest that Pb(2+) exposure during intrauterine life did not substantially affect cortical dopaminergic neurotransmission in adult offspring rats evaluated by means of microdialysis of mPFC and the content of the cortical HO(*). It is likely that striatum, nucleus accumbens or other dopamine rich brain areas are more intricately associated with Pb(2+) precipitated behavioral, dopamine - dependent impairments observed in mammalians.  相似文献   
98.
AIMS: This study aimed to examine the incidence of bone-marrow microinvolvement in non-small cell lung cancer (NSCLC) patients and its correlation with tumour recurrence and prognosis. METHODS: Between March 1997 and August 1998, we analysed 96 bone-marrow specimens (from the posterior iliac crest) of NSCLC patients before surgery. Tumour differentiation showed well differentiated carcinoma in six, moderately differentiated carcinoma in 69, and poorly differentiated carcinoma in 21. p-TNM staging showed stage Ia in five, stage Ib in 33, stage IIb in 19, stage IIIa in 26, stage IIIb in eight, and stage IV in five. The specimens were examined by immunohistochemical staining with anti-human cytokeratin AE1/AE3 and clone MNF116 mixed solution (Ab1, n=96) and/or Ber-EP4 (Ab2, n=80) to detect the presence of malignant epithelial cells in the bone marrow. RESULTS: Positive results were observed in 21 patients (21. 9%). The occurrence of bone-marrow microinvolvement was not related to patient age, sex, cell type, or TNM status. The 30-month disease-free survival rates were 50.2% and 53.9% in bone-marrow negative and bone-marrow positive patients, respectively (P=0.5670); the 30-month cumulative survival rates were 66.7% and 67.6% in bone-marrow negative and bone-marrow positive patients, respectively (P=0.9351). Multivariate analysis failed to demonstrate bone-marrow microinvolvement as an independent prognostic factor. CONCLUSIONS: Our results show that bone-marrow microinvolvement is not unusual, and its occurrence cannot be translated into early tumour recurrence or poor outcome during an intermediate-term follow-up, which means bone-marrow microinvolvement may be an epiphenomenon rather than true metastasis in NSCLC.  相似文献   
99.
Burren CP, Wanek D, Mohan S, Cohen P, Guevara-Aguirre J, Rosenfeld RG. Serum levels of insulin-like growth factor binding proteins in Ecuadorean children with growth hormone insensitivity. Acta Pædiatr 1999; Suppl 428: 185–91. Stockholm. ISSN 0803–5326
Although insulin-like growth factor binding proteins (IGFBPs) are known to be important modulators of the action of insulin-like growth factors (IGFs), regulation of their production in vivo is not completely understood. Serum concentrations of IGFBP-3, -4 and -5 and acid-labile subunit (ALS) were therefore examined in 20 children with growth hormone (GH) insensitivity before and after 6 months of therapy with recombinant human IGF-I (80 or 120 ug/kg twice daily). The IGFBP concentrations in these children were compared with those in 62 GH-deficient children receiving GH therapy for 3 months. Serum levels of IGFBP-3, -4 and -5 and ALS all increased significantly ( p < 0.0001) in GH-deficient children in response to GH therapy, whereas no significant increases occurred in the children with GH insensitivity. These findings indicate that GH is responsible for the regulation of serum levels of IGFBP-3, -4 and -5 and ALS, and that IGF-I does not directly regulate the concentrations of these circulating IGFBPs. □ Growth hormone, growth hormone insensitivity, insulin-like growth factor I, insulin-like growth factor binding protein  相似文献   
100.
射频毁损治疗肝脏肿瘤   总被引:16,自引:4,他引:12  
肝脏肿瘤包括肝原发性肿瘤和肝转移瘤,其治疗目前仍首选手术切除,但确诊时85%~95%的患者已失去手术切除时机,对难以手术治疗的患者已有多种介入治疗方法,如肝动脉栓塞化疗(TAE)、经皮无水酒精注射、微波、激光、冷冻、高功率超声聚焦等。射频毁损(radiofrequency ablation,RFA)是近年国外刚用于肝脏肿瘤治疗的新技术,具有安全性高、并发症少、患者易耐受、肿瘤复发可重复治疗等优点,具有良好的应用前景。 1 射频治疗仪及治疗机制 1868年法国的d'Arsonval发现高于10KHz的高变电流通过活体组织时,并不引起神经肌肉的应激,但局部产热造成组织毁损,自此射频毁损术在神经及心血管领域得以应用并  相似文献   
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