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141.
142.
Inhaled beta(2)-agonists (long-acting as well as short acting) are used world-wide for the relief of asthma symptoms. However, there are few reports which have evaluated the additive effect of short-acting beta(2)-agonists to long-acting beta(2)-agonists on airway resistance measured by a plethysmography. This study was designed to evaluate the additive effect of inhaled short-acting beta(2)-agonists (protecarol) to long-acting beta(2)-agonists (salmeterol) on airway resistance in normal healthy volunteers (S+P group). In addition, to compare the effects of beta(2)-agonists which have different types of intrinsic activities, acute effect of inhaled procaterol adding to procaterol was also evaluated (P+P group). Seven healthy volunteers (all male and all non-smokers) were entered in this study. Pulmonary function was measured by a body plethysmography. Forced expiratory volume per 1 second (FEV1), the maximum flow rate at 25% (V(.) 25), the maximum flow rate at 50% of forced vital capacity (V(.) 50), and airway resistance were measured before and after inhalation of salmeterol (1 dry powder, 50 microg) or procaterol (2 puffs, 20 microg). Sixty minutes after inhalation of salmeterol, or 15 minutes after inhalation of procaterol, inhalation of procaterol (2 puffs, 20 microg) was added, and then pulmonary function was monitored. FEV1, V(.) 25, and V(.) 50 were significantly increased after inhalation of salmeterol as well as procaterol. In addition, airway resistance decreased significantly after inhalation of salmeterol as well as procaterol. In the S+P group, additional decrease of airway resistance after inhalation of procaterol was relatively small compared with the P+P group. In conclusion, although additional bronchodilatoric effects were observed in the S+P and P+P group, the effects seemed to be different based on the intrinsic activity of each beta(2)-agonist.  相似文献   
143.
We evaluated the performances of a ligase chain reaction (LCR)-based assay and two enzyme immunoassays (Chlamydiazyme and IDEIA) in the detection of Chlamydia trachomatis in urine specimens. We compared the results of testing urine specimens by these assays with those of urethral swab culture by examining samples from 131 men with nongonococcal urethritis. Discrepant results were analyzed by testing urethral swab specimens for C. trachomatis by a PCR-based assay. After the resolution of discrepant results, the sensitivity of urethral swab culture was 85.3%, whereas those of the LCR assay, Chlamydiazyme, and IDEIA with urine specimens were 94.1, 82.4, and 94.1%, respectively. The LCR assay and IDEIA were more sensitive than was urethral swab culture. In addition, the LCR assay, with a sensitivity equal to that of IDEIA, was more specific. Overall, the LCR assay proved to be superior to the enzyme immunoassays in detecting C. trachomatis in urine specimens. Testing urine specimens by LCR assay should be a helpful alternative method for diagnosing C. trachomatis urethral infection in men with nongonococcal urethritis.  相似文献   
144.
The dynamics of thermoresponsive phase‐separation processes in aqueous poly(N‐isopropylacrylamide) (PNIPAM) was studied using a laser temperature‐jump technique combined with photometry. The time constant for phase separation (τ) was determined with high accuracy for various molecular weights (M w) and concentrations (C) of PNIPAM in solution. For the C‐dependence, τ decreased with increasing concentration, and eventually converged to a constant value (≈ 50 ms) at high concentration. Such behavior can be interpreted in terms of inter‐polymer‐chain entanglement and diffusion prior to phase separation. On the other hand, there was an optimum value of M w at which the phase separation was fastest. The origins of these experimental results are discussed within the framework of a diffusion‐controlled model.  相似文献   
145.
Autophagy is an evolutionarily conserved process that maintains cellular homeostasis via synthesis, degradation, and subsequent recycling of cellular products under various physiological conditions. However, the link between autophagy and the innate immune system remains unknown. In the present study, we evaluated Toll-like receptor (TLR)-mediated autophagy induction in intestinal epithelial cells (IECs) and its relationship to interleukin (IL)-8 production. IEC-6, HCT-15, RAW264.7, and THP-1 cells were cultured with or without various TLR ligands, followed by evaluation of the expressions of pro-inflammatory cytokines [IL-8, cytokine-induced neutrophil chemoattractants (CINC)-2β, macrophage inflammatory protein (MIP)-2] by real-time PCR and ELISA. To reveal the status of autophagy in IECs and macrophages, light chain 3 (LC3)-II expression was examined using Western blotting and immunofluorescence with confocal microscopy. Also, to evaluate the influence of TLR ligands on autophagy-mediated innate-immune responses, autophagy-related gene (Atg)7 specific siRNA was transfected into intestinal epithelial cells and IL-8 expression was determined following exposure to various TLR ligands. Cells treated with the TLR ligands produced considerable amounts of pro-inflammatory cytokines (IL-8, CINC-2β, MIP-2). Furthermore, the basal levels of LC3-II were markedly higher in IECs as compared to those in macrophages. Our findings indicated that autophagy induction following TLR ligand stimulation was not significantly evident in IECs as compared to macrophages. In addition, Atg7 gene expression silencingled to down-regulation of TLR-mediated IL-8 expression in IECs, which indicates a potential role of autophagy in generating innate-immune responses. In conclusion, autophagy may be an important intracellular machinery for inducing the innate immune system in IECs.  相似文献   
146.
147.
The thymus comprises the mainstream of T cell differentiation which produces conventional T cells and an alternative pathway which produces primordial T cells with intermediate density of T cell receptor (TCR)-CD3 complex on the surface (i.e. intermediate TCR cells or TCRint cells). We induced acute thymic atrophy in mice by an administration of hydrocortisone (10 mg) or irradiation (6.5 Gy). It was demonstrated that CD3intCD4lowNK1.1+ T cells were immediately generated by an alternative intrathymic pathway without passing through the double-positive CD4+8+ stage, when restored from thymic atrophy (days 3-14). These CD3intCD4lowNK1.1+ T cells mediated self-reactivity and appeared even in the periphery. mRNA of an invariant chain of TCR Valpha14Jalpha281 gene product was detected in these CD4low T cells, but not remaining CD4high T cells. The mainstream of T cell differentiation in the thymus was not restored up to day 14 and there was no leakage of self-reactive clones into the population generated through the mainstream. These results reveal that an alternative intrathymic pathway is associated with the generation of self-reactive T cells, in an early restoration phase after thymic atrophy.  相似文献   
148.
149.
OBJECTIVE: We performed a prospective randomized trial in patients with potentially resectable stage IIIA N2 non-small cell lung cancer to confirm the efficacy of induction chemotherapy before surgical resection. METHODS: Patients with stage IIIA N2 non-small cell lung cancer, all with histologically or cytologically confirmed metastases to the ipsilateral mediastinal lymph nodes, were randomly assigned to receive either three cycles of induction chemotherapy (cisplatin at 80 mg/m(2) on 1 day and vindesine at 3 mg/m(2) on 2 days) followed by surgery or surgery alone. RESULTS: This trial was prematurely terminated because the accrual rate was too slow, which lowered the study's statistical power considerably. From June 1993 through April 1998, a total of 62 patients were enrolled, and 31 patients were assigned to each treatment group. The objective clinical response rate of induction chemotherapy was 28%. Complete resection was achieved in 20 patients in the induction chemotherapy group (65%) and 24 in the surgery alone group (77%). Median follow-up was 6.2 years. Median overall survivals were 17 months for the induction group and 16 months for the surgery alone group. The estimated 1-, 3-, and 5-year survivals, respectively, were 68% (95% confidence interval 51%-85%), 23% (95% confidence interval 8%-38%), and 10% (95% confidence interval 0%-20%) for the induction chemotherapy group and 65% (95% confidence interval 48%-82%), 26% (95% confidence interval 11%-41%), and 22% (95% confidence interval 7%-37%) for the surgery alone group. There was no statistically significant difference in survival between the groups (P =.5274). Treatment-related death was not observed in either group. CONCLUSION: This randomized trial to compare induction chemotherapy (cisplatin and vindesine) followed by surgery with surgery alone for patients with stage IIIA N2 non-small cell lung cancer did not demonstrate a survival difference between the groups, although this may have been because the statistical power was limited.  相似文献   
150.
Distortion and movement of the expander during skin expansion.   总被引:2,自引:0,他引:2  
Distortion and movement of tissue expanders can cause expansion of the wrong area, such as the naevus or the scar that is to be resected. In 71 rectangular expanders, we examined the incidence of distortion (over 15 degrees) and movement (over 3 cm). We divided the expanders into three anatomical site groups: scalp, body, and extremities, and compared the complication rate between two study groups (distortion or movement, or not). In total, the incidence of distortion was 15/71 (21%) and that of movement 5/71 (7%). Distortion occurred mainly in the extremities (11/33,33%). The implanted expanders tended to move more often in the body part (3/15, 20%). In the extremities, the bigger the angle between the axis of the implanted expander and that of the extremity, the bigger the angle of distortion. Although the incidence of complications between the two groups was not significant, except for alteration in design of the flap, we recommend that these points should be considered when preoperative plans are being made for appropriate patients.  相似文献   
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