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951.
Open lung biopsy in early-stage acute respiratory distress syndrome   总被引:2,自引:2,他引:0  

Introduction  

Acute respiratory distress syndrome (ARDS) has heterogeneous etiologies, rapid progressive change and a high mortality rate. To improve the outcome of ARDS, accurate diagnosis is essential to the application of effective early treatment. The present study investigated the clinical effects and safety of open lung biopsy (OLB) in patients with early-stage ARDS of suspected non-infectious origin.  相似文献   
952.
Electrical impedance tomography (EIT) is a non-invasive technique used to image the electrical conductivity and permittivity within a body from measurements taken on the body's surface. High-quality static images are required for many medical imaging applications. Forming such images usually requires an accurate way to calculate the expected voltages on the surface resulting from the application of known currents to that surface. This is described as the forward problem. This paper introduces a new method to improve static images by using an improved forward solution which estimates a different conductivity value for each applied current pattern. This method, creating an automatically adjusting forward solution, can improve the sensitivity of static images under many EIT imaging applications. It does so by reducing the boundary effects caused by electrodes and any layered structures near them such as skin. The drawback of this method is that circularly symmetric structures of interest may be suppressed or eliminated from the images. The performance of this method is illustrated in a 2D circular phantom with simulation data from both a FEM model and experimental data.  相似文献   
953.
Extraintestinal pathogenic (ExPEC) Escherichia coli strains of serotype O18:K1:H7 are mainly responsible for neonatal meningitis and sepsis in humans and belong to a limited number of closely related clones. The same serotype is also frequently isolated from the extraintestinal lesions of colibacillosis in poultry, but it is not well known to what extent human and avian strains of this particular serotype are related. Twenty-two ExPEC isolates of human origin and 33 isolates of avian origin were compared on the basis of their virulence determinants, lethality for chicks, pulsed-field gel electrophoresis (PFGE) patterns, and classification in the main phylogenetic groups. Both avian and human isolates were lethal for chicks and harbored similar virulence genotypes. A major virulence pattern, identified in 75% of the isolates, was characterized by the presence of F1 variant fimbriae; S fimbriae; IbeA; the aerobactin system; and genomic fragments A9, A12, D1, D7, D10, and D11 and by the absence of P fimbriae, F1C fimbriae, Afa adhesin, and CNF1. All but one of the avian and human isolates also belonged to major phylogenetic group B2. However, various subclonal populations could be distinguished by PFGE in relation to animal species and geographical origin. These results demonstrate that very closely related clones can be recovered from extraintestinal infections in humans and chickens and suggest that avian pathogenic E. coli isolates of serotype O18:K1:H7 are potential human pathogens.  相似文献   
954.
IgE-mediated hypersensitivity to buckwheat is common in Korea, Japan, and some other Asian countries. However, buckwheat is not a common allergen in Taiwan. We report a woman with asthma who had anaphylactic shock, generalized urticaria, and an acute exacerbation of asthma five minutes after ingesting buckwheat. The patient underwent skin prick and Pharmacia CAP testing (Uppsala, Sweden) for specific IgE to buckwheat, white sesame and soybean as well as other common allergens in Taiwan including Dermatophagoides pteronyssinus (Dp), D. farinae (Df), cat and dog dander, cockroach, egg white, cow milk and codfish. The patient had a strongly positive skin prick test response to buckwheat and positive reactions to Dp and latex. Specific IgE results were class 6 for buckwheat, class 4 for Dp and Df, and class 2 for dog dander, wheat, sesame and soybean. Results of an open food challenge with white sesame and soybean were negative. Although buckwheat is a rare allergen in Taiwan, it can cause extremely serious reactions and should be considered in patients presenting with anaphylaxis after exposure to buckwheat.  相似文献   
955.
Since the mid-1990s, novel G9 rotaviruses have been detected in many countries, suggesting that G9 is a globally important serotype. The molecular epidemiology of G9 rotaviruses in Taiwan from 2000 to 2002 was investigated in this study. G9 rotavirus first appeared in 2000 with 4 cases and constituted 33.8% and 54.8% of the rotavirus-positive samples in 2001 and 2002, respectively. These G9 strains belonged to P[8]G9, subgroup II, and long electropherotype, except one belonged to P[4]G9, subgroup II, and short electropherotype. Nucleotide sequencing and phylogenetic analysis of 52 Taiwanese G9 rotaviruses showed that the VP7 genes shared a high degree of identity to overseas G9 rotaviruses detected after 1993 and that the VP8* portions of the VP4 genes were more closely related to those of local rotaviruses of other G types. The two P[8]G9 strains with high nucleotide identities in the VP7 and the partial VP4 genes, 01TW591 of Taiwan from 2001 and 95H115 of Japan from 1995, varied in four genes, genes 2, 3, 7, and 8, which was revealed by RNA-RNA hybridization. Representative strains for different RNA patterns were also analyzed in the partial VP2 and VP3 genes; the nucleotide identities were high between Taiwanese G9 strains and local G3 or G2 strains. These results suggested that Taiwanese G9 rotaviruses possibly had evolved through reassortment between overseas G9 strains and circulating rotaviruses of other G types.  相似文献   
956.
Human metapneumovirus (HMPV) has been described as a human pathogen associated with respiratory disease in most parts of the world from all age groups. This report presents the first 4 cases of HMPV disease confirmed by the sequences of PCR products in Taiwan.  相似文献   
957.
Cytogenetic abnormalities are observed in approximately two-thirds of patients with acute myeloid leukemia (AML). Chromosome rearrangements are associated with specific subtypes of AML and associated prognosis. We report a patient with AML, M2, who was primarily refractory to standard induction chemotherapy with idarubicin and cytarabine. Flow cytometry of a bone marrow aspirate showed aberrant expression of B-cell markers including CD19. Cytogenetic studies disclosed a translocation between 5q35 and 11q13. Fluorescence in situ hybridization analyses demonstrated that neither the NSD1 nor MLL genes were involved in this case. Further study is required to define conclusively the genes involved and their contribution to pathogenesis in this case.  相似文献   
958.
PURPOSE: It is standard practice in our department to monitor weekly complete blood counts (CBCs) in patients receiving definitive radiation therapy for prostate cancer. The clinical utility and cost effectiveness of this practice has not been analyzed. METHODS AND MATERIALS: The charts of all prostate cancer patients treated with radiation therapy between January 1994 and July 1996 at the Veterans Administration Hospital, Philadelphia, PA were reviewed. CBC values were available for 89 patients. Patients received a median dose of 68 Gy using a four-field box technique and megavoltage photons. Whole-pelvic radiotherapy followed by a conedown to the prostate was administered to 29 patients. Fifty-nine patients received radiation to the prostate alone or prostate and seminal vesicles. Fifty-seven patients received concurrent hormonal therapy which included luteinizing hormone-releasing hormone (LHRH) agonist, antiandrogens, or both. RESULTS: No patient experienced a drop in their hemoglobin, white blood cells (WBCs), or platelets below critical nadirs (defined as WBC < 2 counts x 1000/mm(3), hemoglobin < 8 g/dl, platelet < 50 counts x 1000/mm(3) 2 in WBCs. In the urban area surrounding the Philadelphia Veterans Administration Medical Center, the cost of obtaining a CBC is approximately $30. However, if staff time is considered, the cost of obtaining a weekly CBC during prostate cancer radiotherapy approached $400 per patient. CONCLUSION: These results suggest that weekly monitoring of CBCs in prostate cancer patients undergoing definitive radiotherapy may not be necessary. We recommend a baseline CBC be performed, and if normal, no other monitoring unless clinically indicated. This strategy would result in a cost savings approaching $30,000 per 100 treated patients. Further research on the cost effectiveness and utility of serial blood tests in patients receiving partial body radiation therapy is needed.  相似文献   
959.
The aim of the current study was to examine any difference in the repeat sequence of the monoamine oxidase A (MAOA) gene promoter between males with attention deficit hyperactivity disorder (ADHD) and randomly selected subjects in a community. The role of the MAOA gene promoter in ADHD cases was also investigated. The total of 244 participants included 57 male ADHD subjects as the case group and 187 males, also in southern Taiwan, as the community controls. There was no significantly different distribution in the repeat sequence of the MAOA gene promoter (chi2 = 3.895, d.f. = 3, p = 0.273), and no significantly different distribution of 'long-form' and 'short-form' alleles between the ADHD group and the male community group was noted (chi2 = 2.484, d.f. = 1, p = 0.115). Some aspects of clinical response are mentioned in the discussion of this study which are worth exploring further in the future.  相似文献   
960.

Purpose

Epithelial–mesenchymal transition (EMT) and p53 play important roles in controlling cancer invasion and metastasis. However, discrepancies still exist in the relationship between the expression of an epithelial marker E-cadherin and predicting short survival of patients in many types of cancer. In this study, we aimed to determine the levels of E-cadherin, Twist, and p53 in tumor tissues from patients with oral squamous cell carcinoma (OSCC) and their clinical significances.

Methods

The protein expression of 112 OSCC tumor and 16 benign tissues was examined by immunohistochemistry staining. Overall survival rates of 112 OSCC patients were measured using Kaplan–Meier estimates and the log-rank tests.

Results

E-cadherin and p53 downregulation were found in 70 of 112 (62.5 %) and 66 of 112 (59.0 %), respectively, and Twist overexpression was found in 72 of 112 (64.3 %) studied cases of OSCC patients. Expression of E-cadherin was significantly associated with tumor location (P = 0.004) and mortality (P = 0.010). Patients with lower E-cadherin expression (P = 0.024), betel quid chewing (P = 0.006), smoking (P = 0.001), tumor size >2 cm (P = 0.001), advanced tumor stage (P = 0.043), and recurrence (P < 0.001) exhibited a poorer outcome. Multivariate analysis showed that E-cadherin is an independent marker for survival prediction. Additionally, low E-cadherin expression is significantly correlated with low p53 expression.

Conclusions

E-cadherin is an independent marker for survival prediction in OSCC. Co-evaluation of E-cadherin and p53 expression might be a valuable tool for predicting OSCC patient outcome.  相似文献   
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