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81.
82.
Transesophageal echocardiography continues to have a central role in the diagnosis of infective endocarditis and its sequelae. Recent technological advances offer the option of 3-dimensional imaging in the evaluation of patients with infective endocarditis. We present an illustrative case and review the literature regarding the potential advantages and limitations of 3-dimensional transesophageal echocardiography in the diagnosis of complicated infective endocarditis.A 51-year-old man, an intravenous drug user who had undergone bioprosthetic aortic valve replacement 5 months earlier, presented with prosthetic valve endocarditis. Preoperative transesophageal echocardiography with 3D rendition revealed a large abscess involving the mitral aortic intervalvular fibrosa, together with a mycotic aneurysm that had ruptured into the left atrium, resulting in a left ventricle-to-left atrium fistula. Three-dimensional transesophageal echocardiography enabled superior preoperative anatomic delineation and surgical planning. We conclude that 3-dimensional transesophageal echocardiography can be a useful adjunct to traditional 2-dimensional transesophageal echocardiography as a tool in the diagnosis of infective endocarditis.  相似文献   
83.
A statistical analysis of murine stem cell suicide techniques   总被引:1,自引:0,他引:1  
Quesenberry  PJ; Stanley  K 《Blood》1980,56(6):1000-1005
The clinical application of soft agar cloning techniques for granulocyte-macrophage stem cells (CFU-C) has resulted in a number of contradictory reports that may in part be due to an inadequate data base. Growth of murine CFU-C is more reproducible and less variable than that of human CFU-C. We utilized in vivo hydroxyurea suicide of murine marrow CFU-C to address the question of how many experiments are needed to detect a specific difference with a p of less than 0.05. In 66 experiments the mean marrow CFU-C hydroxyurea kill was 23.3%; 6-9 separate experiments were necessary to detaect differences of 25%-30%. In order to be sure that a 25%-30% difference is not present, 15-21 experiments were required. Using a Dec-20 computer, 1000 samples of sample size 3, 4, or 10 were drawn from the 66 experiments; it was found that with 3 experiments and a true value of 23%, the actually observed value was below 10%, 17% of the time, and was over 40% in 10% of the samplings. In a smaller number of experiments similar results were obtained analyzing 3HTdR suicide of pluripotent stem cells and CFU- C. These data could provide a base from which to judge the validity of studies utilizing the CFU-C technique.  相似文献   
84.
Fibroblast infiltration and collagen deposition result in structural changes in the bowel wall, and lead to strictures in intestinal inflammatory disease. While strictures can also occur in other contexts, such as malignancy, this review focuses on the surgical treatment of stricture secondary to inflammatory bowel disease. Distinguishing between predominantly inflammation vs established fibrosis as the cause of a stricture can be challenging. While inflammatory strictures may be responsive to medication, predominantly fibrotic strictures usually need surgical intervention. Both endoluminal and extraluminal approaches are described in this review. Endoscopic dilatation of strictures is suitable for short‐segment isolated small bowel strictures. Other options are to divide the stricture surgically but preserve the length, performing a strictureplasty or resecting the strictured segment. The mesentery is increasingly recognized as playing a role in stricture recurrence. In a relapsing‐remitting disease such as Crohn's disease, the preservation of intestinal length is essential and balance is needed between this and a complete resection to reduce the risk of recurrence. Pre‐ and postoperative involvement of the multidisciplinary team is essential to improve outcomes in this challenging clinical scenario.  相似文献   
85.
Inadequate resection of the adjoining mesentery is associated with adverse outcome for colon cancer. Disruption of the integrity of the mesenteric lymphatic package has been implicated in this, though not proven. Recent studies have determined mesenteric anatomy and histology and now provide an opportunity to determine accurately the distribution of lymphatic vessels. The aim of this study was to characterise the distribution of the lymphatic vessels (LV) within the small intestinal and colonic mesentery, and in Toldt's fascia, which lies between the mesocolon and underlying retroperitoneum. Mesenteric samples were harvested from 12 human cadavers. Samples were taken from the small bowel mesentery, ascending, transverse, descending mesocolon and from both apposed and non‐apposed portions of the mesosigmoid. Serial sections were stained immunohistochemically with monoclonal antibody D2‐40 (podoplanin), and Masson's Trichrome. Lymphatic vessel (LV) density and radius of diffusion were determined using a stereological approach. A lymphatic network was embedded within the mesenteric connective tissue lattice throughout each mesenteric region. LV were identifiable within the submesothelial connective tissue where they measured 10.2 ± 4.1 μm in diameter and had an average radius of diffusion of 174.72 ± 97.68 μm. Unexpectedly, LV were identified in Toldt's fascia, where they measured 4.3 ± 3.1 μm in diameter and had a radius of diffusion of 165.12 ± 66.26 μm. This is the first study systematically to determine and quantify the distribution of lymphatic vessels within the mesenteric organ and to demonstrate the presence of such vessels within Toldt's fascia. A rich lymphatic network occupies all levels of the mesenteric connective tissue lattice. Within the latter, they are found within 0.1 mm of peritonealised mesenteric surfaces and are separated by an average distance of 0.17 mm and may be particularly vulnerable during surgery.  相似文献   
86.
Background:The purpose of this article is to describe challenges associated with successful use of continuous glucose monitoring (CGM) by young children with type 1 diabetes (T1D) and to detail the techniques and products used to improve the duration of sensor wear.Methods:The DirecNet Study Group conducted 2 studies in 169 children with T1D between the ages of 1 and 9 years who were instructed to wear a CGM device daily. Problems related to skin irritation and sensor adhesiveness in these young children presented challenges to daily use of the CGM. Study coordinators instituted a variety of techniques using commercially available products to attempt to overcome these problems.Results:Three primary factors that contributed to reduced CGM use were identified: the limited body surface area in smaller children, ambient temperature and humidity, as well as the type and duration of physical activity. Using supplemental products to minimize the impact of these factors resulted in improved adherence and reduced skin irritation.Conclusion:Achieving satisfactory adhesion of the CGM sensor and transmitter may involve finding the right supplemental product or combination of products through trial and error. Optimizing adhesion and minimizing skin irritation can significantly improve duration of use and tolerability of CGM devices by young children.  相似文献   
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该文旨在对小唾液腺癌的治疗进行回顾。小唾液腺癌可发生在头颈部很多位置,通常表现为黏膜下肿块。影像学检查是对肿瘤发病部位及病变范围内解剖结构的关系进行评估的基础。切取活检或穿吸活检可以决定肿瘤的病理类型和分级。随着分子生物学技术的不断进步,小唾液腺癌的诊断  相似文献   
90.

BACKGROUND

It is uncertain if computerized physician order entry (CPOE) systems are effective at reducing adverse drug event (ADE) rates in community hospitals, where mainly vendor-developed applications are used.

OBJECTIVE

To evaluate the impact of vendor CPOE systems on the frequency of ADEs.

DESIGN AND PATIENTS

Prospective before-and-after study conducted from January 2005 to September 2010 at five Massachusetts community hospitals. Participants were adults admitted during the study period. A total of 2,000 charts were reviewed for orders, medication lists, laboratory reports, admission histories, notes, discharge summaries, and flow sheets.

MAIN MEASURES

The primary outcome measure was the rate of preventable ADEs. Rates of potential ADEs and overall ADEs were secondary outcomes.

KEY RESULTS

The rate of preventable ADEs decreased following implementation (10.6/100 vs. 7.0/100 admissions; p?=?0.007) with a similar effect observed at each site. However, the associated decrease in preventable ADEs was balanced against an increase in potential ADEs (44.4/100 vs. 57.5/100 admissions; p?p?=?0.03), which was driven by non-preventable events (4.0/100 vs. 11.7/100 admissions; p?CONCLUSIONS Adoption of vendor CPOE systems was associated with a decrease in the preventable ADE rate by a third, although the rates of potential ADEs and overall ADEs increased. Our findings support the use of vendor CPOE systems as a means to reduce drug-related injury and harm. The potential ADE rate could be reduced by making refinements to the vendor applications and their associated decision support.  相似文献   
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