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31.
Anthony Yuen Bun Teoh Philip Wai Yan Chiu So Fei Hon Tony Wing Chung Mak Enders Kwok Wai Ng James Yun Wong Lau 《Surgical endoscopy》2013,27(4):1422-1427
Background
Endoscopic submucosal dissection (ESD) is a technically demanding procedure, and exposure of the submucosa depends on the action of gravity and submucosal injection. The aim of the study was to investigate the effectiveness of the Endolifter® as a traction device for enhancing submucosal visualization during ESD.Methods
This was a prospective ex vivo comparative study conducted between September 2010 and March 2011 in the Prince of Wales Hospital. Consecutive ESDs were performed by four experienced endoscopists in an ex vivo ESD model with or without the Endolifter®. The Endolifter® allows simultaneous grasping, retracting and lifting of the mucosa during ESD, resulting in exposure of the submucosa. Each of the procedures were recorded and reviewed later by two independent assessors. The outcome measures included the proportion of time that the submucosa was visualized during the procedures (SM ratio), procedural times, perforation rates, amount of submucosal injections, and the difficulty of the procedure.Results
Forty-eight gastric ESD procedures were performed on the model. The SM ratio was higher in the Endolifter® group (P = 0.007), particularly for lesions located at the antrum (P < 0.001). The time required for submucosal dissection and the total procedural time were also less in the Endolifter® group. The endoscopists rated the ESD procedures in the Endolifter® group as less difficult (P = 0.033).Conclusions
The Endolifter® improved submucosal visualization during gastric ESD and reduces the difficulty of performing the procedures. The device may improve the ease of performing ESD in low-volume centers or large mucosal lesions. 相似文献32.
Uren RF Howman-Giles R Chung DK Spillane AJ Noushi F Gillett D Gluch L Mak C West R Briody J Carmalt H 《Breast (Edinburgh, Scotland)》2012,21(4):480-486
BackgroundHistorical studies of lymphatic drainage of the breast have suggested that the lymphatic drainage of the breast was to lymph nodes lying in the antero-pectoral group of nodes in the axilla just lateral to the pectoral muscles. The purpose of this study was to confirm this is not correct.MethodsThe hybrid imaging method of SPECT/CT allows the exact anatomical position of the sentinel lymph node (SLN) in the axilla to be documented during pre-operative lymphoscintigraphy (LS) in patients with breast cancer. We have done this in a series of 741 patients. The Level I axillary nodes were defined as anterior, mid or posterior. This was related to the anatomical location of the primary cancer in the breast.ResultsA SLN was found in the axilla in 97.8% of our patients. Just under 50% of SLNs located in the axilla were not in the anterior group and lay in the mid or posterior group of Level I axillary nodes. There was a SLN in a single node field in 460 patients (63%), two node fields in 261(36%), three node fields in 6 and four node fields in 1 patient.ConclusionAxillary lymphatic drainage from the breast is not exclusively to the anterior (or antero-pectoral) group of Level I nodes.SynopsisSPECT/CT lymphoscintigraphy shows that the breast does not always drain to the anterior group of Level I lymph nodes in the axilla but may drain to the mid axilla and/or posterior group in about 50% of patients with breast cancer regardless of the location of the cancer in the breast. These data redefine lymph drainage from the breast to axillary lymph nodes. 相似文献
33.
Provision of adequate nutrition is a cornerstone of the management of infants and very young children with chronic kidney disease (CKD). Very young children with CKD frequently have poor spontaneous nutritional intake. Because growth depends strongly on nutrition during early childhood, growth in very young children with CKD is often suboptimal. In this review we will consider the mechanisms and manifestations of inadequate nutritional status in very young children with CKD, mechanisms mediating inadequate nutritional intake, and the optimal nutritional management of this special population. In addition, we suggest an approach to the assessment of nutritional status, including the use of body mass index in infants. Five major nutritional components are considered: energy, macronutrients, fluids and electrolytes, micronutrients, and calcium/phosphorus/vitamin D. The use of adjunctive therapies, including appetite stimulants, treatment of gastroesophageal reflux and gastric dysmotility, enhanced dialytic clearance, and growth hormone, is also briefly discussed. 相似文献
34.
David T. Wong MD Jaisy J. Yang BHSc Hannah Y. Mak MSc Narasimhan Jagannathan MD 《Journal canadien d'anesthésie》2012,59(7):704-715
Purpose
This article is a narrative review regarding the usage and effectiveness of introducers or catheters to facilitate tracheal intubation through a supraglottic airway (SGA) as an alternative intubation technique in normal and difficult airway management.Sources
Relevant articles were obtained through Medline (1948-July 2011). The articles were subsequently cross-referenced for additional literature, and only articles published in English were included.Principal findings
In this review, we consider 32 reports using the LMA Classic?, LMA Unique?, LMA ProSeal?, LMA Supreme?, AuraOnce?, and i-gel? as SGA conduits for intubation. In 13 articles, the use of an Aintree Intubation Catheter was described as an intubation introducer and resulted in high success rates in both elective and emergent situations. Eight studies used a guidewire exchange catheter technique. Although blind intubation using a guidewire resulted in a high failure rate, these studies found that using a bronchoscope improved successful intubation. Ten studies showed that insertion of a gum elastic bougie with a bronchoscope as an intubation introducer has high success rates compared with blind bougie insertion. One article described the use of a small endotracheal tube as an intermediary for tracheal intubation.Conclusions
In failed intubation scenarios, supraglottic airways, such as the LMA Classic? or LMA ProSeal? can serve as a conduit for tracheal intubation. A number of techniques using introducers or catheters can facilitate the insertion of an adequately sized endotracheal tube, particularly guided by a bronchoscope. Usage of introducers or catheters through a supraglottic airway may be a useful alternative intubation technique in difficult airway management. 相似文献35.
Wendy Mak Xinyu Shao Colin R. Dunstan Markus J. Seibel Hong Zhou 《Calcified tissue international》2009,85(6):538-545
Glucocorticoids exert both anabolic and catabolic effects on bone. Previously, we reported that endogenous glucocorticoids
control mesenchymal lineage commitment and osteoblastogenesis through regulation of Wnt signaling in osteoblasts. Here, we
investigated the effects of glucocorticoids on Wnt expression in mature osteoblasts. Mature osteoblasts and their immature
progenitors were separately isolated from Col2.3-GFP transgenic mice in which mature osteoblasts are identifiable through
GFP expression. mRNA levels of Wnt2, Wnt2b, Wnt4, Wnt5a, Wnt10b, and Wnt11 were 4- to 12-fold higher in osteoblasts compared
to their progenitors (P < 0.05). Expression of Wnt7b and Wnt10b in osteoblasts was modulated by corticosterone (CS), in a biphasic fashion with 3-
to 3.5-fold upregulation at 10 nM CS (P < 0.01) and 50% downregulation at 100 nM CS (P < 0.05). CS 100 nM also increased expression of the Wnt inhibitors sFRP-1 and DKK-1 two- to threefold (P < 0.05). We conclude that the contrasting anabolic and catabolic effects of glucocorticoids on bone are, at least in part,
mediated through the regulation of Wnt expression and its inhibitors in mature osteoblasts. 相似文献
36.
Edwin Pelfrene Peter Vlerick France Kittel Rudolf P. Mak Marcel Kornitzer Guy De Backer 《Stress and health》2002,18(1):43-56
The Karasek Job Demand–Control model has as its central tenet the so‐called ‘strain hypothesis’, stating that the most adverse health outcomes are to be expected in ‘high strain’ jobs characterized by high job demands and low job control. Later, this model was elaborated, stating that ‘isolated’ high strain workers experiencing low worksite social support are even more worse off. This is labelled the ‘iso‐strain hypothesis’. However, in the literature, the question was raised whether a high level of job control may (1) mitigate or buffer the effects of high job demands on psychological well‐being, or alternatively whether (2) a high level of social support may buffer the negative impact of high strain on psychological well‐being. In this study among 16 335 male workers and 5084 female workers in Belgium, four indicators of psychological well‐being are considered: feelings of depression, feelings of fatigue, sleep problems and use of psychoactive drugs. Both in men and in women, the general strain hypothesis and the iso‐strain hypothesis alike are corroborated regarding the cross‐sectional associations adjusted for age, level of education and living situation. This is most clear with respect to feelings of depression, less so with respect to the use of psychotropic drugs. The buffer hypotheses however are definitely not supported by our data. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
37.
Cheung WW Kuo HJ Markison S Chen C Foster AC Marks DL Mak RH 《Journal of the American Society of Nephrology : JASN》2007,18(9):2517-2524
We have recently shown that genetic or pharmacological blockade of the melanocortin-4 receptor (MC4-R) attenuates uremia-associated cachexia. However, the potential clinical utility of this approach has been limited by the need to deliver a peptide MC4-R antagonist into the ventricles of the brain. NBI-12i is a recently developed small molecule MC4-R antagonist, with high affinity and selectivity that penetrates the central nervous system after peripheral administration. We tested whether NBI-12i would also be effective in attenuating uremia-associated cachexia in a mouse model. Intraperitoneal administration of NBI-12i stimulated food intake and weight gain in uremic mice. Furthermore, NBI-12i-treated uremic mice gained lean body mass, fat mass, and had a lower basal metabolic rate compared to vehicle-treated and diet-supplemented uremic mice, which lost both lean body mass and fat mass and had an increase in basal metabolic rate. We found that NBI-12i normalizes the expression of uncoupling protein, which is normally upregulated in uremic mice, and we speculate that this may contribute to the drug's protective effect. These data underscore the importance of melanocortin signaling in the pathogenesis of uremia-associated cachexia and demonstrate the potential of peripheral administration of MC4-R antagonists as a novel therapeutic approach. 相似文献
38.
To Wong Betty Yuen-Ting Lau Ho-Leung Mak Man-Wah Pang Cecilia Cheon Shing-Kai Yip 《International urogynecology journal》2006,17(6):593-597
A territory-wide telephone survey was conducted in Hong Kong to assess the prevalence, knowledge, and treatment-seeking behaviour of Chinese women with urinary incontinence, using validated Chinese version of Urogenital Distress Inventory (UDI-6) and Incontinence Impact Questionnaire (IIQ-7). Women, 540, aged between 17 to 77 years were interviewed. Of the respondents, 40.8% reported stress urinary incontinence, 20.4% had urge incontinence and 15.9% had mixed incontinence. Among these, 16.0% reported quality of life impairment; 9.3% felt frustrated with low morale, and 15.2% had nervous and anxiety problems. However, as many as 78.3% of the respondents did not know that stress urinary incontinence is a disease entity, and 60.6% thought that leakage of urine was a normal aging process. For those respondents having stress urinary incontinence, the first treatment of choice was physiotherapy. The second choice was medication, and surgical treatment was the last option. Respondents with stress urinary incontinence showed higher education level. 相似文献
39.
Loss of protein stores, presenting as clinical wasting, is reported to have a prevalence of 30–60% and is an important risk factor for mortality in chronic kidney disease (CKD) patients. There is debate as to whether the clinical wasting in CKD patients represents malnutrition or cachexia. Malnutrition results from inadequate intake of nutrients, despite a good appetite, and manifests as weight loss associated with adaptive metabolic responses such as decreased basic metabolic rate and preservation of lean body mass at the expense of fat mass. Furthermore, the abnormalities in malnutrition can usually be overcome simply by supplying more food or altering the composition of the diet. In contrast, cachexia is characterized by maladaptive responses such as anorexia, elevated basic metabolic rate, wasting of lean body tissue, and underutilization of fat tissue for energy. Diet supplementation and intradialytic parenteral nutrition have not been successful in reversing cachexia in CKD. The etiology of cachexia in CKD is complex and multifactorial. Two major factors causing muscle wasting in uremia are acidosis and decreased insulin responses. Inflammation secondary to cytokines may also play a significant role. The hypoalbuminemia of CKD patients is principally associated with inflammation and not changes in food intake. There is also recent evidence that hypothalamic neuropeptides may be important in the downstream signaling of cytokines in the pathogenesis of cachexia in CKD. Elevated circulating levels of cytokines, such as leptin, may be an important cause of uremia-associated cachexia via signaling through the central melanocortin system. Further research into the molecular pathways leading to cachexia may lead to novel therapeutic therapy for this devastating and potentially fatal complication of CKD.Supported by grants from the National Institute of Health R01 DK 50780 and K24 DK59574 to RHM. 相似文献
40.
In vivo imaging of the human zonular apparatus with high-resolution ultrasound biomicroscopy 总被引:4,自引:0,他引:4
K. Ludwig Erika Wegscheider J. P. Hoops Anselm Kampik 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(5):361-371
· Background: To investigate the potential of high-resolution ultrasound biomicroscopy (UBM) for studying the zonular apparatus
of human beings in vivo. · Methods: Using transducer frequencies of 34 MHz and 50 MHz, criteria were developed to identify
transcorneal and transscleral sections that allowed reproducible identification of the different fiber groups of the zonular
architecture. For that purpose, 10 volunteers between the ages of 14 and 41 years underwent high-resolution ultrasound biomicroscopy
under conditions of consensual far- and near-accommodation. The online video recordings of the respective UBM investigations
were afterwards analyzed image by image. Good visibility of zonular fibers was obtained when the ultrasound wave propagation
comprised an angle close to 90° with the fiber orientation and when the oscillations of the UBM scan had a strict radial orientation
towards the limbus and avoided, simultaneously, the ciliary processes. · Results: In all the volunteers, high-resolution ultrasound
biomicroscopy imaged the zonular fiber groups known from histology. In addition, it detected fibers that do not follow the
course of the inner ciliary body surface but take a direct route from the ora serrata to the lens. It also demonstrated that
fibers that seem to change direction at crossings with other fibers. Under conditions of near-accommodation, the zonular fibers
showed signs of relaxation. · Conclusions: High-resolution ultrasound biomicroscopy seems well suited for in vivo investigations
of the zonular apparatus and of accommodation in man. The results support the fundamental features of the Helmholtz theory
on accommodation.
Received: 8 June 1998 Revised version received: 7 September 1998 Accepted: 14 September 1998 相似文献