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排序方式: 共有601条查询结果,搜索用时 46 毫秒
31.
32.
Katsushige Yamashiro M.D. Kiyomi Taira M.T. Satoshi Matsubayashi M.T. Manabu Azuma M.T. Dai Okuyama M.T. Manami Nakajima M.T. Hiroko Takeda M.D. Hiroaki Suzuki M.D. Naoki Kawamura M.T. Fumihiko Wakao M.D. Yukako Yagi Ph.D. 《Diagnostic cytopathology》2009,37(10):727-731
The limitation of cytologic still images is one of the reasons why telecytology has not met with widespread acceptance by the cytology community. Cytologic still image only displays a single depth of field, and this is a particularly acute problem in cytology where the specimen is often much thicker than a single microscopic depth of focus. In this article, we examine the validity of a “z‐axis” video of a microscopic field of interest. After observing videos of fields of interest from 10 cases, five cytotechnologists reached suitable cytologic findings and diagnosed the fields correctly in great majority of cases. Five other cytotechnologists, who looked only at a single representative still image, could not always make a correct diagnosis. The difference between two observer groups was statistically significant by Wilcoxon's matched pairs signed‐rank test. The results indicate that “z‐axis” video of microscopic field of interest provides a similar experience to “focusing through” observation of the specimen under a microscope and may improve an accuracy of primary telecytodiagnosis. And we expect that video image telecytology will strongly influence cytology, especially in education and training. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
33.
Masamune Higashigawa Yukako Kawasaki Noriko Yodoya Yusuke Omori Yuji Nashida Yoshio Amemiya Takashi Fujiwara Masakazu Inoue 《Pediatrics international》2009,51(5):684-686
Background: Few data are available for the recent occurrence of Mycoplasma infections in children in Japan. The purpose of the present study was therefore to identify the prevalence of Mycoplasma infections in children in Japan.
Methods: IgM antibodies to M. pneumoniae were prospectively determined using the Meridian ImmunoCard Mycoplasma test in hospitalized patients with lower respiratory tract infections between January 2004 and June 2007. A total of 858 hospitalized patients aged 0–15 years (445 male, 413 female), diagnosed as having acute pneumonia or bronchitis, were enrolled. The number of patients with pneumonia or bronchitis was 331 (male/female, 167/164) and 527 (male/female/ 278/249), respectively. Two hundred and five of the 858 patients (23.9%) were ImmunoCard positive. Of the 205 patients, 121 children and 84 children were diagnosed as having pneumonia and bronchitis, respectively. One hundred and forty-three of the 727 patients (19.7%) <5 years of age were ImmunoCard test positive.
Conclusions: M. pneumoniae infection is not rare in children aged <5 years in Japan. 相似文献
Methods: IgM antibodies to M. pneumoniae were prospectively determined using the Meridian ImmunoCard Mycoplasma test in hospitalized patients with lower respiratory tract infections between January 2004 and June 2007. A total of 858 hospitalized patients aged 0–15 years (445 male, 413 female), diagnosed as having acute pneumonia or bronchitis, were enrolled. The number of patients with pneumonia or bronchitis was 331 (male/female, 167/164) and 527 (male/female/ 278/249), respectively. Two hundred and five of the 858 patients (23.9%) were ImmunoCard positive. Of the 205 patients, 121 children and 84 children were diagnosed as having pneumonia and bronchitis, respectively. One hundred and forty-three of the 727 patients (19.7%) <5 years of age were ImmunoCard test positive.
Conclusions: M. pneumoniae infection is not rare in children aged <5 years in Japan. 相似文献
34.
OBJECTIVE: To examine the relationship between self-estimated whole body size and fatness and whole body and regional composition, and the relationship between self-estimated whole body fatness and self-estimated regional fatness in Japanese university students. RESEARCH METHODS AND PROCEDURES: This was a cross-sectional study using Japanese university students (110 men and 79 women). The percentage of body fat, fat mass (FM), and fat-free mass (FFM) were measured by underwater weighing and used as body composition variables. Subcutaneous fat thicknesses were determined at seven sites by ultrasonography to estimate regional body composition, and six circumferences and four breadths to estimate regional size. Relative body size and fatness were self-estimated using a questionnaire. RESULTS: Only women tended to estimate themselves as being fatter than they actually were. Self-estimated body fatness moderately correlated with the percentage of body fat (men, r = 0.41; women, r = 0.40) FM (men, r = 0.50; women, r = 0.51), and body mass index (r = 0.56 for men and 0.56 for women). After adjusting for the percentages of body fat and FM, self-estimated fatness correlated with body mass index (r = 0.31 for men and r = 0.37 for women). Among self-estimated regional fatness, self-estimated abdominal fatness had the strongest correlation with self-estimated whole body fatness in both genders. DISCUSSION: The low correlation between estimated and actual body fatness in both genders indicates that Japanese university students, especially women, inaccurately estimate their percentage of body fat. In fact, both men and women primarily estimate their whole body fatness by body weight relative to height. 相似文献
35.
Yamashita S Konishi K Yamazaki Y Taki Y Sakane T Sezaki H Furuyama Y 《Journal of pharmaceutical sciences》2002,91(3):669-679
The aim of the present study was to develop new and better protocols for a short-term Caco-2 cell culture system for use in rapid screening of intestinal drug absorption. Caco-2 cells were cultured according to several protocols for short-term cell culture to obtain monolayers. The effects of serum (fetal bovine serum, FBS) in the culture medium and of the period of cell culture on the barrier function and transporter activities of the monolayers were examined. The barrier function was estimated both from the transepithelial electrical resistance (TEER) and the permeability of [(14)C]mannitol. Transporter activities were monitored by measuring the permeability of [(14)C]glycylsarcosine for oligopeptide transporter (PepT1) and of rhodamine 123 for P-glycoprotein (P-gp). Caco-2 monolayers obtained by 3-day culture in the BIOCOAT HTS Caco-2 Assay System, developed by Becton Dickinson Bioscience, showed much higher permeability to hydrophilic compounds, such as mannitol, compared with those obtained by the standard 21-day culture system, due to the leaky structure of cell junctions. The newly developed 3-day protocol, which includes 10% FBS in the culture medium during the first day of culture, markedly enhanced TEER and lowered mannitol permeability of the monolayers. This protocol allowed us to better determine the rank order of permeability of compounds, giving results equivalent to those in the 21-day culture system. The longer culture period gave tighter monolayers, and the maximum value of TEER was obtained with 5 days in culture. However, after 5 days in culture, the integrity of monolayers decreased gradually. The highest activities of transporters, PepT1 and P-gp, in monolayers were obtained at days 5 or 6 of culture by the new protocol with FBS-containing medium. These results indicate that by a simple modification of the short-term culture protocol, it is possible to obtain Caco-2 monolayers with better barrier properties and higher activity of transporters that are equivalent to those found in the 21-day Caco-2 culture system. 相似文献
36.
Kondo T Nojiri M Hishikawa Y Togawa E Romanovicz D Brown RM 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(22):14008-14013
Biodirected epitaxial nanodeposition of polymers was achieved on a template with an oriented molecular surface. Acetobacter xylinum synthesized a ribbon of cellulose I microfibrils onto a fixed, nematic ordered substrate of glucan chains with unique surface characteristics. The substrate directed the orientation of the motion due to the inverse force of the secretion during biosynthesis, and the microfibrils were aligned along the orientation of the molecular template. Using real-time video analysis, the patterns and rates of deposition were elucidated. Field emission scanning electron microscopy revealed that a strong molecular interaction allowed for the deposition of nascent biosynthesized 3.5-nm cellulose microfibrils with inter-microfibrillar spacings of 7-8 nm on the surface of the template. The cellulose was deposited parallel to the molecular orientation of the template. Directed cellulose synthesis and ordered movement of cells were observed only by using a nematic ordered substrate made from cellulose, and not from ordered crystalline cellulose substrates or ordered cellulose-related synthetic polymers such as polyvinyl alcohol. This unique relationship between directed biosynthesis and the ordered fabrication from the nano to the micro scales could lead to new methodologies for the design of functional materials with desired nanostructures. 相似文献
37.
Kenjiro Koga Yoichi Kusawake Yukako Ito Nobuyuki Sugioka Nobuhito Shibata Kanji Takada 《European journal of pharmaceutics and biopharmaceutics》2006,64(1):82-91
The aim of this study was to clarify the mechanism by which caprylocaproyl macrogol-8 glyceride (Labrasol) enhances the intestinal absorption of gentamicin sulfate (GM), a drug that has poor permeability but relatively high solubility. We studied the following characteristics: (i) the phase behavior of Labrasol in aqueous solution, (ii) the affinity of GM to Labrasol micelles, and (iii) the interaction between Labrasol and membrane lipids. We measured the critical micelle concentration of Labrasol in aqueous solution to be approximately 0.01%. The average diameters of Labrasol micelles in 2% and 25% solutions were approximately 10 nm and 20 nm, respectively, indicating that micelles increase in size with increasing Labrasol concentration. Although GM dissolved in 5% Labrasol solution was dialyzable, GM dissolved in either 25% or 50% Labrasol solutions was not, suggesting that GM exists in the hydrophilic region of the Labrasol micelle or in the high affinity region of the micelle surface where GM is retained. In membrane permeability experiments and electrophysiological studies conducted with rat ileum, only 25% Labrasol solution enhanced GM permeability, but did not remarkably affect membrane resistance. Furthermore, Labrasol increased membrane lipid fluidity as determined by fluorescence anisotropy in porcine intestinal brush border membrane liposomes. These results suggest that high concentrations of Labrasol solution enhance membrane permeability of GM via a transcellular rather than a paracellular route. We propose the following mechanism: Labrasol micelles grow when the concentration of Labrasol exceeds 20%, at which point GM shows high affinity for the hydrophilic region of the micelles. Since Labrasol micelles increase membrane lipid fluidity, the membrane permeability of GM is concomitantly enhanced. 相似文献
38.
Purpose. CO2 absorbents convert sevoflurane to fluoromethyl-2,2-difluoro-1-(trifluoromethyl) vinyl ether (compound A), whose toxicity
in rats raises concern regarding the safety of sevoflurane in a low-flow system. The type of CO2 absorbent is one of factors that affect compound A concentration in the anesthetic circuit. The aim of the present study
was to investigate the concentration of compound A in an anesthetic model circuit following the use of different brands of
soda lime and Baralyme.
Methods. We measured the concentrations of compound A in four different brands of CO2 absorbent using a low-flow (1 l·min−1 fresh gas) model circuit in which 2% sevoflurane was circulated. Sodasorb II, Baralyme, Sofnolime and Wakolime-A were used
as CO2 absorbents. The concentration of compound A was measured hourly, and the temperature of the CO2 absorbent was monitored.
Results. The maximum concentration of compound A in the circuit was highest for Baralyme (25.5 ± 0.6 ppm) (mean ± SD), followed by
Sodasorb II (18.9 ± 1.6 ppm), Wakolime-A (16.1 ± 0.7 ppm), and Sofnolime (15.8 ± 1.4 ppm). The maximum temperature was 50.8
± 1.3°C for Baralyme, 48.8 ± 1.3°C for Wakolime-A, 47.0 ± 1.4°C for Sodasorb II, and 43.5 ± 3.9°C for Sofnolime.
Conclusion. The relative concentrations of compound A in the low-flow circuit were Baralyme > Sodasorb II > Wakolime-A = Sofnolime.
Received: August 27, 1999 / Accepted: January 13, 2000 相似文献
39.
Saikawa Y Kubota T Takahashi T Akatsu Y Nakamura R Yoshida M Shigematsu N Otani Y Kumai K Hibi T Kitajima M 《Oncology reports》2005,13(5):865-870
We aim to clarify beneficial effect of pre-operative radiation with chemotherapy in highly advanced gastric cancer patients, evaluating histological response, toxicity and patients' quality of life (QOL). We used pre-operative radiation with S-1 and low-dose cisplatin to treat 8 patients with highly advanced gastric cancer (clinical stage IV) in a pilot study. Clinical staging after therapy showed 5 PRs (partial response), 2 NCs (no change), and 1 PD (partial disease) following evaluation of the primary tumor and suspicious metastatic lesions in the lymph nodes, esophagus, liver, and peritoneum, for a response rate of 62.5% (5/8 cases). Of 8 patients, 6 underwent surgery, and 2 of these 6 patients had a histologically complete response (grade 3 effect) and 3 patients had a partial response (grade 2 effect), suggesting that a high histological response (5/6 cases; 83.3%) is expected by the chemoradiation. The survival analysis showed that 5 out of the 8 patients died within 10 months after initiating therapy, while 3 patients are alive without recurrence at 15, 18, and 30 months after therapy, suggesting a relatively good outcome for clinical stage IV gastric cancer. All cases showed grade 2-4 bone marrow suppression toxicity and/or grade 0-2 gastro-intestinal toxicity, while 5 out of 8 patients (62.5%) showed improvement in appetite loss at the end of the therapy, indicating that the patients' quality of life (QOL) was preserved. Chemoradiation may be a powerful regimen for obtaining histological response with tolerable toxicity and improved QOL in highly advanced gastric cancer patients. 相似文献
40.
Kayashima T Okazaki Y Katayama T Hori K 《Journal of nutritional science and vitaminology》2005,51(5):343-348
This study examined the influence of a low level of dietary lectin (0.34%), at a dose that did not affect body weight or food intake, on the concentration of serum cholesterol and fecal excretion of neutral sterols in rats fed a diet containing 0.50% cholesterol and 0.13% sodium cholate for 12 d. In experiment 1, rats fed a diet with 0.34% lectin, concanavalin A, had significantly lower concentrations of serum total cholesterol and hepatic cholesterol, a higher ratio of HDL-cholesterol to total cholesterol, enhanced excretion of fecal neutral sterols and reduced apparent cholesterol absorption or digestibility as compared with rats fed a diet without lectin. Fecal excretion of acidic sterols was unaffected by dietary lectin. In contrast, dietary 0.34% lectin had no significant effect on concentrations of serum total protein or glucose. In experiment 2, we examined whether the cholesterol-lowering activity of the lectin was responsibility for its carbohydrate-binding activity. The effect of dietary lectin on concentrations of serum and hepatic cholesterol and excretion of fecal neutral sterols was prevented by simultaneous administration of methyl-alpha-D-mannopyranoside with specific affinity for the carbohydrate-binding sites of the lectin. These results suggest that dietary lectins might reduce concentrations of serum and hepatic cholesterol by a mechanism involving higher excretion of neutral sterols and that these alterations might be associated with the carbohydrate-binding activity of lectin. 相似文献