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991.
Recent advancements in modern medical diagnoses have required a huge increase of the use of equipment such as CT and ultrasound machines. Correspondingly, the storage and dissemination of these medical images have become an important issue to medical professionals. Unfortunately, management of these images has traditionally been slow and cumbersome. With the prevalence of the personal computer, however, along with increased network bandwidth, it is now possible to handle this information electronically as well as wirelessly. The Picture Archiving and Communication System (PACS) is at the forefront of this revolution. Yet, commercially available PACS software is generally prohibitively expensive for hospitals with limited financial resources. A dilemma among many hospitals is deciding how to acquire and implement the proper PACS system without unduly affecting the budget. In this paper, a full function, efficient, and economical PACS system is presented as a viable, non-compromising option for many small and medium-sized hospitals. This system, designed and developed mainly by the physicians and technicians of Puli Christian Hospital (PCH), with the assistance from academia, allows for customization to fit the needs of individual hospitals. This system can be used as the foundation of a hospital's health information infrastructure and to enhance e-hospital service.  相似文献   
992.
Ability to persist in human macrophages is central to the virulence of Mycobacterium tuberculosis and is not invariable among various strains. Differential gene expression that is associated with phenotypic virulence may provide additional information of virulent genes involved in the pathogenesis of M. tuberculosis, which is not fully elucidated. Three hypervirulent strains of M. tuberculosis isolated from patients suffering with tuberculous meningitis were shown to grow more rapidly inside human macrophages in a previous study. In the current investigation, expression of 7 mycobacterial genes (fadE28, mce1A, mymA, acr, sigA, sugC, and Rv3723) of these strains during ex vivo macrophage challenge and in vitro acid shock was quantified by real-time PCR. Using rrs gene as a normalisation gene, fadE28 gene exhibited differential gene expression that is associated with phenotypic virulence, whereas the other 6 genes showed indistinguishable expression patterns. Up-regulation of fadE28 gene in the hypervirulent strains may account for virulence by increasing the efficiency of beta-oxidation, which is important for the persistence in macrophages as M. tuberculosis uses fatty acids preferably inside phagosome of macrophages. The fadE28 gene, together with its adjacent genes may also be critical in the process of lipid modification that could facilitate parasitism in human macrophages.  相似文献   
993.
With recent progress in treatment modalities, mortality from upper gastrointestinal (UGI) bleeding has decreased appreciably. The aim of this study was to establish how UGI bleeds are managed in Korean patients with cirrhosis and to evaluate treatment outcomes. A total of 479 episodes of acute UGI bleeding in 464 patients with cirrhosis were included during a six-month period at nine tertiary medical centers. Treatment outcomes were assessed by failure to control bleeding, rebleeding and mortality. The source of bleeding was esophagogastric varices in 77.7% of patients, nonvariceal lesions in 15.9%, and undefined in 6.5%. For control of bleeding, endoscopic and pharmacologic treatments were used in 74.7% and 81.9% of patients, respectively. Variceal ligation was a major technique for endoscopic treatment (90%), and terlipressin and somatostatin were the main pharmacologic agents used (96.4%). Initial hemostasis was achieved in 86.8% of cases, but rebleeding occurred in 3.8% and 16.8% of cases within five days and six weeks of hemorrhage, respectively. Five-day and six-week mortality were 11.3% and 25.9%, respectively. Survival of patients with variceal bleeding seems to be remarkably improved than previous reports, which may suggest the advances in hemostatic methods for control of variceal hemorrhage.  相似文献   
994.
Gwak SJ  Bhang SH  Kim IK  Kim SS  Cho SW  Jeon O  Yoo KJ  Putnam AJ  Kim BS 《Biomaterials》2008,29(7):844-856
Cardiomyocytes in the body are subjected to cyclic mechanical strain induced by the rhythmic heart beating. In this study, we tested the hypothesis that cyclic strain promotes cardiomyogenesis of embryonic stem cell-derived cardiomyocytes (ESCs). ESCs cultured on elastic polymer [poly(lactide-co-caprolactone), PLCL] scaffolds subjected to cyclic strain in vitro displayed elevated cardiac gene expression compared to unstrained controls. Six weeks after implantation into infarcted rat myocardium, the elastic cardiac patches (ESC-seeded PLCL scaffolds) showed reduced fibrotic tissue formation, likely due to a combination of lower apoptotic activity, higher vascular endothelial growth factor (VEGF) expression, and more extensive angiogenesis in the strained versus unstrained control [ESC-seeded, non-elastic poly(lactide-co-glycolide) scaffolds] patches. Importantly, cardiac gene expression was upregulated in the elastic patches compared to control, with evidence for cardiomyocyte-specific microstructures including myofibrillar bundles and Z-lines. This study shows that the use of an elastic polymer scaffold designed to permit mechanical strain transduction as a cell transplantation vehicle significantly increases cardiomyogenesis of the implanted ESCs.  相似文献   
995.
Columnar cell lesions (CCLs) are one of the most common abnormalities in the adult female human breast, characterized by the presence of columnar-shaped epithelial cells lining enlarged terminal-duct lobular units. CCLs are being seen increasingly in core biopsies taken for the non-palpable calcifications. The increased incidence may reflect improved delineation and recognition of CCLs by pathologists or a true increase in incidence related to biological and/or environmental factors. Columnar cell-like lesions have been described under a variety of names such as blunt duct adenosis, flat epithelial atypia, and ductal intraepithelial neoplasia type DIN1a. The current histologic classification used by some pathologists divides them into simple columnar cell change and columnar cell hyperplasia, both of which can occur with or without atypia. Columnar cells lack mature luminal or basal/myoepithelial phenotype markers, but they are usually positive for estrogen receptor-alpha. The cellular origin of CCLs and their possible relationship to either expansion or metaplasia of a preexisting normal cell phenotype remains unclear. CCLs are frequently associated with lobular and ductal in situ tumors and invasive lobular and tubular carcinomas. The relationship and natural history of CCLs to invasive ductal carcinoma is enigmatic, but they may prove of clinical relevance when detected by screening mammography.  相似文献   
996.
Cheng TY  Ju KC  Ho CS  Chen YY  Chang H  Lin WL 《Medical physics》2008,35(4):1387-1397
This study investigated the feasibility of using a split-focused ultrasound transducer to perform thermal surgery on breast tumors, based on a multidirectional heating scheme. The transducer is a square section of a sphere with a radius of 10 cm. The transducer was tilted such that its acoustic beam was 45 degrees relative to the rib surface, and its focal zone was arranged by a shift of 6 mm away from the center of the planning target volume. The multifocus switching technique was employed to enhance the heating efficiency. When a single transducer was used, the transducer sonicated from a certain position for a given duration, and then rotated sequentially to continue the heating. Computer simulations and in vitro phantom experiments have been studied for this heating system. Both simulation and experimental results demonstrated that the system based on a multidirectional heating scheme is capable of generating a proper thermal lesion within 8 min. Meanwhile, from the simulation results, the rib heating was effectively alleviated by tilting the transducer to induce the total reflection at the muscle/bone interface. While using multiple ultrasound transducers, an appropriate arrangement was designed to have the same configuration of acoustic beams as is used for a single-transducer strategy. The simulation results from the four-transducer strategy indicated that the heating results could be further improved. This study revealed that it is very promising to have an appropriate arrangement of a single split-focused ultrasound transducer with mechanical rotation, or to have multiple split-focused transducers that use multidirectional heating for breast tumor thermal therapy.  相似文献   
997.
We designed and fabricated silicon probe with nanophotonic force sensor to directly stimulate neurons (PC12) and measured its effect on neurite initiation and elongation. A single-layer pitch-variable diffractive nanogratings was fabricated on silicon nitride probe using e-beam lithography, reactive ion etching and wet-etching techniques. The nanogratings consist of flexure folding beams suspended between two parallel cantilevers of known stiffness. The probe displacement, therefore the force, can be measured through grating transmission spectrum. We measured the mechanical membrane characteristics of PC12 cells using the force sensors with displacement range of 10 mum and force sensitivity 8 muN/mum. Young's moduli of 425 +/- 30 Pa are measured with membrane deflection of 1% for PC12 cells cultured on polydimethylsiloxane (PDMS) substrate coated with collagen or laminin in Ham's F-12K medium. In a series of measurements, we have also observed stimulation of directed neurite contraction up to 6 mum on extended probing for a time period of 30 min. This method is applicable to measure central neurons mechanics under subtle tensions for studies on development and morphogenesis. The close synergy between the nano-photonic measurements and neurological verification can improve our understanding of the effect of external conditions on the mechanical properties of cells during growth and differentiation.  相似文献   
998.
BACKGROUND: Anti-Müllerian hormone (AMH) is a biomarker that predicts the number of antral follicles and is involved in follicle arrest for women with polycystic ovary syndrome (PCOS). We investigated the association between the characteristic hyperandrogenemia, insulin resistance (IR), AMH, and the morphology and size of ovaries for women with PCOS. METHODS: A total of 99 Taiwanese women with PCOS who were willing to undergo vaginal ultrasonography were enrolled in this cross-sectional study. RESULTS: The number of antral follicles and the ovarian volume showed a significant correlation with AMH, total testosterone and the free androgen index, but not with age, body mass index (BMI) or the homeostasis model assessment of insulin resistance (HOMA-IR). AMH had a significant negative association with both BMI and HOMA-IR. Multiple stepwise regression analysis demonstrated that AMH, BMI and total testosterone were independently related to the number of antral follicles. AMH and total testosterone were the main determinants for ovarian volume in a stepwise regression model. CONCLUSIONS: Our results suggest that not only the AMH level, but also obesity, IR and elevated androgen levels may relate to the development of the large size of antral follicle pool and ovarian volume in women with PCOS. Obesity and IR may enhance the follicular excess through the dysregulation of AMH or through the pathway of hyperandrogenemia. These findings might partly explain why adequate body weight management and improvement in IR can improve the ovulatory function for women with PCOS.  相似文献   
999.

Objective

To investigate the clinical features and microbiology of patients with diarrheal diseases in Taiwan.

Methods

From March 2014 to October 2014, patients with diarrheal diseases referred from the community clinics were enrolled into our prospective study. Demographics and clinical features of the participants were acquired. Stool samples were examined by the Luminex Gastrointestinal Pathogen Panel assay. Data were analyzed by SAS version 9.4.

Results

A total of 545 patients were enrolled into this study. Male and adults accounted for 52.3% and 82.6% of patients, respectively. The median age was 36 years. Enteropathogen(s) was identified in 43.3% of patients and 8.5% of them had more than one agent in their stool samples. Viruses, especially norovirus GI/GII, were the predominant agents of gastroenteritis. Moreover, Campylobacter species was the most common bacterial agent. Bloody stool was frequently reported in patients with bacterial diarrhea (P = 0.002); contrarily, watery stool was significantly associated with viral diarrhea (P < 0.0001). Regional variation and seasonality of microbiological distribution were also observed.

Conclusion

In Taiwan, viruses were the predominant pathogens among patients with diarrheal diseases who visited community clinics. The therapeutic strategies for diarrheal patients should be based on the epidemiological and clinical characteristics.  相似文献   
1000.
An exclusive feature of dendritic cells (DCs) is their ability to cross‐present exogenous antigens in MHC class I molecules. We analyzed the fate of protein antigen in antigen presenting cell (APC) subsets after uptake of naturally formed antigen‐antibody complexes in vivo. We observed that murine splenic DC subsets were able to present antigen in vivo for at least a week. After ex vivo isolation of four APC subsets, the presence of antigen in the storage compartments was visualized by confocal microscopy. Although all APC subsets stored antigen for many days, their ability and kinetics in antigen presentation was remarkably different. CD8α+ DCs showed sustained MHC class I‐peptide specific CD8+ T‐cell activation for more than 4 days. CD8α? DCs also presented antigenic peptides in MHC class I but presentation decreased after 48 h. In contrast, only the CD8α? DCs were able to present antigen in MHC class II to specific CD4+ T cells. Plasmacytoid DCs and macrophages were unable to activate any of the two T‐cell types despite detectable antigen uptake. These results indicate that naturally occurring DC subsets have functional antigen storage capacity for prolonged T‐cell activation and have distinct roles in antigen presentation to specific T cells in vivo.  相似文献   
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