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21.
Choi CM  Um SW  Yoo CG  Kim YW  Han SK  Shim YS  Lee CT 《Chest》2004,126(5):1516-1521
STUDY OBJECTIVES: To evaluate the incidence and clinical significance of delayed pneumothorax, and to analyze the influence of multiple variables on the rate of delayed pneumothorax associated with transthoracic needle biopsy (TTNB) of the lung. STUDY DESIGN: Prospective study. SETTING: Tertiary care university hospital. STUDY SUBJECTS: Adult patients underwent TTNB from June 2001 to June 2002. MEASUREMENTS AND RESULTS: Among the 458 patients included in this study, 280 fluoroscopic-guided, 21 CT-guided, and 157 ultrasonography-guided lung biopsies were performed. A follow-up chest radiograph was obtained immediately, and 3 h, 8 h, and 24 h after the biopsy procedure. Pneumothorax that had not developed up to 3 h but developed later was defined as a delayed pneumothorax. Patients with a symptomatic or enlarged pneumothorax were treated using a pigtail catheter or chest tube. Variables such as age, gender, lesion size, location, presence of an emphysematous change, biopsy guidance methods, and biopsy devices were analyzed. Pneumothorax developed in 100 of the 458 patients (21.8%), and delayed pneumothorax developed in 15 patients (3.3%). Seventeen patients, including 3 patients with delayed pneumothorax, required a pigtail catheter or a chest tube insertion. The pigtail catheter or chest tube insertion rate in delayed pneumothorax was 20% (3 of 15 patients). Female gender and the absence of an emphysematous change correlated with an increased rate of delayed pneumothorax (p < 0.05). Lesion size, location, biopsy guidance methods, devices, and underlying diseases were not correlated with the delayed pneumothorax rate. CONCLUSIONS: The incidence of delayed pneumothorax was 3.3% of all TTNBs. Female gender and the absence of an emphysematous change were identified as risk factors for delayed pneumothorax. Delayed pneumothorax is clinically important because of its considerable incidence and the necessity for pigtail catheterization or chest tube insertion in these patients.  相似文献   
22.
Su-A.  KIM  Sang-Won  UM  Jae-Uk  SONG  Kyeongman  JEON  Won-Jung  KOH  Gee Young  SUH  Man Pyo  Jung  O. Jung  KWON  Jong Heon  PARK  Chin A.  YI  Joungho  HAN  Hojoong  KIM 《Respirology (Carlton, Vic.)》2010,15(1):150-154
Background and objective: Bronchoscopic resection of endobronchial hamartomas has been reported to have a favourable outcome. This study describes the bronchoscopic features of endobronchial hamartoma and reports the clinical outcome of bronchoscopic intervention. Methods: A retrospective analysis was conducted of patients with histologically proven endobronchial hamartomas, diagnosed in the 10‐year period 1999–2009 to elucidate the clinical, radiological and bronchoscopic features of hamartoma and to describe the clinical outcomes. Results: Seventeen of the 135 patients with pulmonary hamartomas were diagnosed as having endobronchial hamartomas. CXR was abnormal in 11 of the 17 patients. On chest CT (n = 16), the median diameter of the lesion was 15.6 mm. Calcification and areas of focal fat in the lesion, the diagnostic CT findings of pulmonary hamartoma, were found in two of 16 (12.5%) patients. At bronchoscopy (n = 16), all tumours had a mass appearance and most were smooth surfaced round masses (50.0%) with 18.8% having a ‘stalk’. Bronchoscopic forceps biopsies were performed in 13 patients, which resulted in five patients (38.5%) being diagnosed with endobronchial hamartoma. Fifteen patients were treated with rigid or flexible bronchoscopic resection, one had lobectomy, and one had no intervention. No procedure‐related mortalities or late complications developed. Conclusions: Bronchoscopic intervention appears to be a safe and effective method to resect endobronchial hamartomas.  相似文献   
23.
Background  Human leukocyte antigen (HLA) molecules are known to play an important role in host-defense mechanisms. The aim of this study was to evaluate the association between HLA alleles and lung disease caused by nontuberculous mycobacteria (NTM) in Korean patients. Methods  Seventy-eight patients with NTM lung disease (48 patients with Mycobacterium avium-intracellulare complex [MAC] infection and 30 patients with Mycobacterium abscessus infection) were included in the study. HLA-A, -B, and -DRB1 genotyping was performed by polymerase chain reaction using sequence-specific primers. Data from 485 healthy Korean individuals were used as a control. Results  When compared to controls, patients with NTM lung disease showed an increased frequency of DRB1*11 (OR = 1.91, 95% confidence interval [CI] = 1.01–3.64, p = 0.045, corrected p [pC] > 0.05). In the subgroup analysis, patients with MAC lung disease had an increased frequency of B*46 (OR = 2.23, 95% CI = 1.05–4.73, p = 0.044, pC > 0.05). Conclusions  Our data suggest that in a Korean population, patients with NTM lung disease and healthy subjects differ in the frequencies of some HLA alleles. However, when considering corrected p values, our findings are inconclusive. S.-W. Um and C.-S. Ki contributed equally to this work.  相似文献   
24.
C(2) domains are autonomously folded protein modules that generally act as Ca(2+)- and phospholipid-binding domains and/or as protein-protein interaction domains. We now report the primary structures and biochemical properties of a family of evolutionarily conserved mammalian proteins, referred to as E-Syts, for extended synaptotagmin-like proteins. E-Syts contain an N-terminal transmembrane region, a central juxtamembranous domain that is conserved from yeast to human, and five (E-Syt1) or three (E-Syt2 and E-Syt3) C-terminal C(2) domains. Only the first E-Syt C(2) domain, the C(2)A domain, includes the complete sequence motif that is required for Ca(2+) binding in C(2) domains. Recombinant protein fragments of E-Syt2 that include the first C(2) domain are capable of Ca(2+)-dependent phospholipid binding at micromolar concentrations of free Ca(2+), suggesting that E-Syts bind Ca(2+) through their first C(2) domain in a phospholipid complex. E-Syts are ubiquitously expressed, but enriched in brain. Expression of myc-tagged E-Syt proteins in transfected cells demonstrated localization to intracellular membranes for E-Syt1 and to plasma membranes for E-Syt2 and E-Syt3. Structure/function studies showed that the plasma-membrane localization of E-Syt2 and E-Syt3 was directed by their C-terminal C(2)C domains. This result reveals an unexpected mechanism by which the C(2)C domains of E-Syt2 and E-Syt3 functions as a targeting motif that localizes these proteins into the plasma membrane independent of their transmembrane region. Viewed together, our findings suggest that E-Syts function as Ca(2+)-regulated intrinsic membrane proteins with multiple C(2) domains, expanding the repertoire of such proteins to a fourth class beyond synaptotagmins, ferlins, and MCTPs (multiple C(2) domain and transmembrane region proteins).  相似文献   
25.
Because additive effects of inhaled corticosteroids and long-acting anticholinergics are unclear, we undertook this study to compare the efficacy of tiotropium alone and tiotropium plus budesonide in patients with chronic obstructive pulmonary disease. The study subjects were randomized to receive either tiotropium 18 microg once daily with or without budesonide 200 microg twice daily for 6 weeks. The efficacy variables were changes in trough forced expiratory volume in one second (FEV1), St. George's Respiratory Questionnaire (SGRQ), 6-minute walk distance (6MWD), and use of rescue medication. One hundred patients were randomized and 81 completed the study. The mean age was 64.0 yr, and the mean FEV1 was 39.7% predicted. Compared with tiotropium alone (N=40), the tiotropium/budesonide combination (N=41) was related to an improvement in the SGRQ total score (tiotropium -2.8 units and tiotropium/budesonide -5.6 units, p=0.003). 6MWD was improved by 13.5 m in the tiotropium group and by 22.5 m in the tiotropium/budesonide group (p=0.031). Changes in trough FEV1 and the use of rescue medication were similar between two groups. In conclusion, compared with tiotropium alone, the tiotropium/budesonide combination was related to an improved health-related quality of life. These data support that low-dose budesonide may enhance the efficacy of tiotropium.  相似文献   
26.

Statement of problem

Although many systems are used to polish zirconia, a comparison of the performance of zirconia and feldspathic porcelain polishing systems is lacking.

Purpose

The purpose of this in vitro study was to compare the effects of 3 polishing systems on surface roughness, zirconia phase transformation, and durability of the polishing systems when applied to zirconia and feldspathic porcelain.

Material and methods

Three polishing systems were evaluated: Z1, a zirconia polishing system; Z2, a zirconia polishing system, and F1, a feldspathic porcelain polishing system. Three ceramic systems were evaluated: PR and ZM zirconia specimens (diameter 15 mm, height 2 mm; 23 specimens each) and CB feldspathic porcelain specimens of the same size (15 specimens). A rough surface was created on the 3 types of specimens (15 specimens each) to model an occlusal adjustment under the same conditions. Polishing was carried out with the 3 polishing systems for 2 minutes each. Surface roughness was measured with a 3-dimensional (3D) optical profiler. The surface was also observed with a scanning electron microscopy. X-ray diffraction analysis was performed for 8 PR or ZM zirconia specimens polished by using the Z1 and Z2 systems for 8 minutes to evaluate the phase transformation of zirconia before, during, and after polishing. These specimens were compared and analyzed for phase transformation that might have occurred during the polishing of the specimens. After finishing the surface roughness experiment and the phase transformation experiment, the volumes of the polishers were measured with a 3D volume scanner and compared with those before the experiments to evaluate the durability of the polishing system. A statistical analysis of all data was performed using 2-way ANOVA and the Tukey honest significant difference test (α=.05).

Results

The 2 zirconia polishing systems (Z1, Z2) created a significantly (P<.001) smoother surface, regardless of the type of specimens used for polishing, than the feldspathic porcelain polishing system (F1). When polishing treatment was carried out on zirconia specimens for 8 minutes, the maximum percentages of monoclinic phase increased by 0.03% in the Z1 system and by 0.09% in the Z2 system. The volume change for the durability evaluation of the polishing system was 13.35 and 29.37% in the Z1 system, 2.05 and 5.92% in the Z2 system, and 3.60 and 4.95% in the F1 system, respectively.

Conclusions

Zirconia polishing systems created a smoother surface on zirconia than the feldspathic porcelain polishing system. No significant changes in the phase transformation of zirconia were found before and after polishing. Each polishing system showed different levels of wear resistance.  相似文献   
27.
The variant B.1.1.7 of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the RNA virus causing the pandemic more than a year worldwide, was reported from United Kingdom (UK) in late December 2020. It was reported that mortality increases by 65% and transmissibility increases by 70%, which may result in an increase of reproduction number to 1.13-1.55 from 0.75-0.85. To analyze the global increasing trend of the variant B.1.1.7, we extracted results of B.1.1.7 from GISAID on May 11 and May 12, 2021, and conducted a dose-response regression. It took 47 days to reach 20% and 121 days to reach 50% among the sequence submitted from UK. In Korea, cases of B.1.1.7 have increased since the first report of three cases on December 28, 2020. Positive rate of B.1.1.7 in Korea was 21.6% in the week from May 9 to May 15, 2021. Detection rate of the variants is expected to increase further and new variants of SARS-CoV-2 are emerging, so a close monitoring and control would be maintained for months.  相似文献   
28.
29.
This study evaluated the effect of UV absorbers on the dimensional accuracy of zirconia specimens fabricated by additive manufacturing using a digital light process. Zirconia suspension for additive manufacturing was prepared by setting the volume fractions (0, 0.005, 0.05, and 0.1%) of various UV absorbers. The effect of UV absorber content was evaluated through curing thickness, geometric overgrowth model design, linear deviation, and microstructure evaluation before and after sintering. Statistical analysis was performed by Kruskal–Wallis H and post-tested by the Bonferroni correction method. There was no significant difference in the cure depth according to the presence or absence of the UV absorber, the difference in geometric overgrowth was from 2.1 to 12.5%, and the overgrowth significantly decreased as the amount of added UV absorber increased. This result may contribute to improved precision of 3D multilayer ceramic products.  相似文献   
30.

Purpose

To investigate clinical implications of delta neutrophil index (DNI) to discriminate adult onset Still''s disease (AOSD) from sepsis.

Materials and Methods

We reviewed the medical records of 13 patients with AOSD and 33 gender and age-matched patients with sepsis. In all subjects, microbial tests were performed to exclude or confirm sepsis. All laboratory data were measured two or three times during the first 3 days and represented by their mean levels. DNI was measured automatically by ADVIA 2120 for the first 3 days.

Results

There were no significant differences in white blood cell counts, neutrophil proportion, erythrocyte sedimentation rate and C-reactive protein between two groups. AOSD patients had notably lower DNI than sepsis patients regardless of the presence of bacteremia or not. However, both DNI and ferritin were not significant independent factors for predicting sepsis in the multivariate logistic regression analysis. Meanwhile, the area under the receiver operating characteristic curve (AUROC) of DNI was slightly higher than that of ferritin. When we set DNI of 2.75% as the cut-off value for predicting sepsis, 11 (84.6%) of AOSD patients had a DNI value below 2.75% and 2 (15.4%) of them had a DNI over 2.75% (relative risk for sepsis 176).

Conclusion

We suggest that DNI may be a useful marker for differential diagnosis of AOSD from sepsis in the early phase as supplementary to ferritin.  相似文献   
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