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31.
32.
Chun Hsing Liao Yu Tsung Huang Fang Yeh Chu Tsui Hsien Lin Po Ren Hsueh 《Journal of microbiology, immunology, and infection》2008,41(4):355-357
Time to positivity is an available parameter in automated blood culture systems. We report a patient with persistent methicillin-resistant Staphylococcus aureus bacteremia who received various regimens for treatment of methicillin-resistant S. aureus, and demonstrate that monitoring of the time to positive blood culture might be helpful in the early recognition of treatment failure. 相似文献
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Chung-Chuan Chou Shengmei Zhou Hideki Hayashi Motoki Nihei Yen-Bin Liu Ming-Shien Wen San-Jou Yeh Michael C. Fishbein James N. Weiss Shien-Fong Lin Delon Wu Peng-Sheng Chen 《The Journal of physiology》2007,580(3):895-906
We hypothesize that remodelling of action potential and intracellular calcium (Cai ) dynamics in the peri-infarct zone contributes to ventricular arrhythmogenesis in the postmyocardial infarction setting. To test this hypothesis, we performed simultaneous optical mapping of Cai and membrane potential ( V m ) in the left ventricle in 15 rabbit hearts with myocardial infarction for 1 week. Ventricular premature beats frequently originated from the peri-infarct zone, and 37% showed elevation of Cai prior to V m depolarization, suggesting reverse excitation–contraction coupling as their aetiology. During electrically induced ventricular fibrillation, the highest dominant frequency was in the peri-infarct zone in 61 of 70 episodes. The site of highest dominant frequency had steeper action potential duration restitution and was more susceptible to pacing-induced Cai alternans than sites remote from infarct. Wavebreaks during ventricular fibrillation tended to occur at sites of persistently elevated Cai . Infusion of propranolol flattened action potential duration restitution, reduced wavebreaks and converted ventricular fibrillation to ventricular tachycardia. We conclude that in the subacute phase of myocardial infarction, the peri-infarct zone exhibits regions with steep action potential duration restitution slope and unstable Cai dynamics. These changes may promote ventricular extrasystoles and increase the incidence of wavebreaks during ventricular fibrillation. Whereas increased tissue heterogeneity after subacute myocardial infarction creates a highly arrhythmogenic substrate, dynamic action potential and Cai cycling remodelling also contribute to the initiation and maintenance of ventricular fibrillation in this setting. 相似文献
35.
Edwin A Bronsky Umit Yegen Ching Ming Yeh Lawrence V Larsen Giovanni Della Cioppa 《Annals of allergy, asthma & immunology》2002,89(4):407-412
BACKGROUND: Patients with exercise-induced bronchospasm (EIB) may benefit from a prophylactic beta2-adrenergic agonist that combines rapid onset with long duration of action. OBJECTIVE: To compare the protective effect against EIB of a single inhaled dose of formoterol powder delivered via the Aerolizer inhaler (Novartis Pharmaceuticals, East Hanover, NJ) with the effect of placebo and albuterol. METHODS: Eighteen patients with EIB were randomized to treatment in a double-blind, placebo-controlled, four-way, crossover study. Seventeen patients completed all four crossover periods. Each patient received in random sequence a single dose of formoterol (12 or 24 microg), albuterol (180 microg), or placebo at intervals of 5 +/- 2 days. Pulmonary function measurements were taken before and after exercise challenge tests (ECTs) at 15 minutes postdosing and at 4, 8, and 12 hours postdosing. RESULTS: Both doses of formoterol produced significantly greater protection against EIB, compared with placebo, at all timepoints (P < or = 0.016). The two doses of formoterol were not significantly different from one another at any time. Protection against EIB with albuterol was clinically significant only for the 15-minute ECT and was statistically superior to placebo for the 15-minute and 4-hour ECTs. Although formoterol and albuterol exhibited a rapid onset of action, formoterol provided longer-lasting protection over the 12-hour observation period. Rescue medication was used substantially less with either dose of formoterol, compared with albuterol or placebo. All treatments were well tolerated. Two-hour postdosing electrocardiograms and vital signs were unremarkable for all study treatments. CONCLUSION: A single dose of formoterol (12 or 24 microg) provides protection against EIB within 15 minutes of dosing and persists for up to 12 hours. Formoterol is safe and well tolerated. 相似文献
36.
Robert F. Phalen Hsu-Chi Yeh Otto G. Raabe David J. Velasquez 《Anatomical record (Hoboken, N.J. : 2007)》1973,175(2):255-517
A method for producing flexible silicone rubber casts of the airways of the lungs in-situ is described. Casts are made to correspond to lung volumes occurring during normal breathing. The lung is prepared for casting by replacing the air within with CO2 followed by filling with degassed physiological saline. The saline dissolves the CO2 gas within the airways allowing for a bubble-free finished cast. Casting compound is then slowly injected through the trachea. The saline diffuses out of the lung and passes out of the thorax through several small slits in the thoracic wall. After the injection is completed, the cast lung is allowed to cure in-situ before it is removed and the tissue digested away. Finished casts have an overall shape corresponding closely to the shape of the thorax. Casts produced by this in-situ method appear to have more realistic geometrical relationships than those produced from excised lungs. 相似文献
37.
Macroporous scaffolds are typically utilized in tissue engineering applications to allow for the migration of cells throughout the scaffold and integration of the engineered tissue with the surrounding host tissue. A method to form macroporous beads with an interconnected pore structure from alginate has been developed by incorporating gas pockets within alginate beads, stabilizing the gas bubbles with surfactants, and subsequently removing the gas. Macroporous scaffolds could be formed from alginate with different average molecular weights (5-200 kDa) and various surfactants. The gross morphology, amount of interconnected pores, and total void volume was investigated both qualitatively and quantitatively. Importantly, macroporous alginate beads supported cell invasion in vitro and in vivo. 相似文献
38.
Mucous membrane pemphigoid (MMP) is an autoimmune mucocutaneous blistering disease characterized by autoantibodies to components within the basement membrane zone. In this study, we report the titers of autoantibodies to antigens in the BMZ, in the sera of 13 patients, treated with intravenous immunoglobulin as monotherapy over a consecutive 18-month period. Using bovine gingiva lysate as substrate in an immunoblot assay, autoantibodies to human bullous pemphigoid antigens (BPAg1 and BPAg2), human beta4 integrin, and laminin 5 were measured. A statistically significant (P < 0.05) decline in the autoantibody titers to beta4-integrin was observed after 3.42 months of initiating the IVIg therapy. These titers were undetectable after 13 months of therapy. The titers of antibodies to BPAg1 and BPAg2 did not correlate with disease activity or response to therapy. Antibodies to laminins were not detected. In patients with MMP, autoantibody titers to beta4-integrin correlate with disease activity and response to therapy. 相似文献
39.
Immunohistochemical processing of Long-Evans retina wholemounts using an antiserum directed against rat, human corticotropin releasing factor revealed a group of immunoreactive amacrine cells. Two subpopulations could be distinguished based primarily on the location of their cell bodies. One subpopulation had cell bodies situated along the junction of the inner nuclear layer and the inner plexiform layer. The other subpopulation had cell bodies in the ganglion cell layer. The latter was judged to be displaced amacrine cells since double-label experiments indicated that the pattern of corticotropin releasing factor-like immunoreactive staining in the ganglion cell layer did not coincide with that of ganglion cells labeled retrogradely with fluorogold. Corticotropin releasing factor-like immunoreactive amacrine cells on either side of the inner plexiform layer emitted processes which ramified extensively in sublamina 5 and, to a lesser degree, in sublamina 4. A minority of these cells also sent a single process to ramify in sublamina 1. Throughout the retina, corticotropin releasing factor-like immunoreactive cells were distributed relatively evenly, with a tendency to peak in the superior temporal region. Despite the anatomical classification into two subpopulations, it is proposed that the corticotropin releasing factor-like immunoreactive cells are functionally one system, influencing preferentially synaptic interactions associated with the inner half of the inner plexiform layer. The results of this study provide anatomical basis for further investigations of corticotropin releasing factor as a putative peptidergic neurotransmitter in the retina. 相似文献
40.
Incidence and case-fatality rates resulting from the 1998 enterovirus 71 outbreak in Taiwan 总被引:6,自引:0,他引:6
Lu CY Lee CY Kao CL Shao WY Lee PI Twu SJ Yeh CC Lin SC Shih WY Wu SI Huang LM 《Journal of medical virology》2002,67(2):217-223
In 1998, an epidemic of hand-foot-and-mouth disease and herpangina caused by enterovirus 71 occurred in Taiwan, leaving many fatalities and severely handicapped survivors in its wake. The reasons this rather common pathogen would cause such a large-scale epidemic remain unknown. A seroepidemiological survey to elucidate the epidemiological characteristics of this outbreak, including its incidence and case-fatality rates was undertaken. Microneutralization tests for antibodies against enterovirus 71 were used to screen four collections of serum samples: 1) 202 specimens taken from individuals > or = 4 years old in 1994; 2) 245 specimens collected from individuals of all ages in 1997; 3) 1,258 specimens collected from individuals of all ages in 1999; and 4) sera samples from a birth cohort of 81 children who had yearly blood samples taken from 1988-98. After the maternal antibody had declined, the seropositive rates began to increase with age. Approximately half of all children aged 6 years or older were enterovirus 71 seropositive. Significantly higher seropositive rates were noted in 1999 than in 1997, in children aged 0.5-3 years. The incidence of enterovirus 71 infection during the epidemic was estimated to be 13-22%, with the higher rates in younger children. The case-fatality rate was highest (96.96 per 100,000) in infants aged 6-11 months, and declined in older children. The results showed that enterovirus 71 is endemic in Taiwan. The apparent lack of large-scale enterovirus 71 activity in the 3 years before 1998 might have been the prelude to the epidemic's appearance in 1998, and might suggest that enterovirus 71 infection will reappear every few years. The lack of a protective antibody in younger children may account for the high incidence and case-fatality rate in this age group. 相似文献