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排序方式: 共有1902条查询结果,搜索用时 15 毫秒
71.
Ki Cheol Chang Joo Youn Oh Youn Seok In Mee Kum Kim Ki Cheul Shin Won Ryang Wee Jin Hak Lee Myung Gyu Park 《Journal of Korean medical science》2009,24(4):701-707
We designed a randomized, double blinded, 3-months controlled prospective clinical study to investigate effects of oral uridine on the ocular surface in dry eye patients. Twenty-seven patients who diagnosed as dry eye with lower than 5 mm of wetting in the Schirmer strip, with corneal epithelial erosion and who completely followed-up till 3 months were enrolled. Corneal-conjunctival fluorescein staining, non-anesthetic Schirmer test, impression cytology, and Ocular Surface Disease Index (OSDI) were evaluated in the experimental and placebo groups at the baseline, 1 and 3 months after start of medication in a double blinded manner. Fluorescein stain score of the cornea was markedly decreased in oral uridine group compared to the placebo group at 3 months after medication (P=0.032, Mann-Whitney U test). The Schirmer wetting score for the oral uridine group was significantly increased (P=0.001, Wilcoxon signed rank test) at 3 months and its difference between two groups was statistically significant (P=0.030, Mann-Whitney U test). OSDI scores were significantly decreased at 1 and 3 months in treatment group. Oral uridine is effective in treatment of dry eyes. 相似文献
72.
Jung Joo Lee †Bum Soo Kim Jaesoon Choi †Hyuk Choi †Chi Bum Ahn Kyoung Won Nam †Gi Seok Jeong ‡Choon Hak Lim §Ho Sung Son †§Kyung Sun 《Artificial organs》2009,33(8):627-633
The bellows-type pneumatic ventricular assist device (VAD) generates pneumatic pressure with compression of bellows instead of using an air compressor. This VAD driver has a small volume that is suitable for portable devices. However, improper pneumatic pressure setup can not only cause a lack of adequate flow generation, but also cause durability problems. In this study, a pneumatic pressure regulation system for optimal operation of the bellows-type VAD has been developed. The optimal pneumatic pressure conditions according to various afterload conditions aiming for optimal flow rates were investigated, and an afterload estimation algorithm was developed. The developed regulation system, which consists of a pressure sensor and a two-way solenoid valve, estimates the current afterload and regulates the pneumatic pressure to the optimal point for the current afterload condition. Experiments were performed in a mock circulation system. The afterload estimation algorithm showed sufficient performance with the standard deviation of error, 8.8 mm Hg. The flow rate could be stably regulated with a developed system under various afterload conditions. The shortcoming of a bellows-type VAD could be handled with this simple pressure regulation system. 相似文献
73.
†Gi Seok Jeong †Chang Mo Hwang †Kyoung Won Nam †Chi Bum Ahn †Ho Chul Kim †Jung Joo Lee †Jaesoon Choi †‡Ho Sung Son †‡Yong Hu Fang †‡Kuk Hui Son †§Choon Hak Lim †‡Kyung Sun 《Artificial organs》2009,33(8):657-662
In this study, we developed a small pneumatic actuator that can be used as an extracorporeal biventricular assist device. It incorporated a bellows-transforming mechanism to generate blood-pumping pressure. The cylindrical unit is 88 ± 0.1 mm high, has a diameter of 150 ± 0.1 mm, and weighs 2.4 ± 0.01 kg. In vitro, maximal outflow at the highest pumping rate (PR) exceeded 8 L/min when two 55 mL blood sacs were used under an afterload pressure of 100 mm Hg. At a pumping rate of 100 beats per minute (bpm), maximal hydraulic efficiency was 9.34% when the unit supported a single ventricle and 13.8% when it supported both ventricles. Moreover, pneumatic efficiencies of the actuator were 17.3% and 33.1% for LVAD and BVAD applications, respectively. The energy equivalent pressure was 62.78∼208.10 mm Hg at a PR of 60∼100 bpm, and the maximal value of dP/dt during systole was 1269 mm Hg/s at a PR of 60 bpm and 979 mm Hg/s at a PR of 100 bpm. When the unit was applied to 15 calves, it stably pumped 3∼4 L/min of blood at 60 bpm, and no mechanical malfunction was experienced over 125 days of operation. We conclude that the presently developed pneumatic actuator can be utilized as an extracorporeal biventricular assist device. 相似文献
74.
Sung Kyu Hong Byung Kyu Han Seung Tae Lee Sung Soo Kim Kyung Eun Min Sung Jin Jeong Hyeon Jeong Seok-Soo Byun Hak Jong Lee Gheeyoung Choe Sang Eun Lee 《World journal of urology》2009,27(2):271-276
Objectives A paucity of data exists on actual pathology of the contemporary patients strictly categorized as having low-risk prostate
cancer. We tried to identify useful preoperative predictors of Gleason score upgrading in patients who underwent radical retropubic
prostatectomy (RRP) for low-risk prostate cancer diagnosed via multi-core prostate biopsy.
Methods A total of 203 patients who underwent radical RRP for low-risk prostate cancer, as defined by D’Amico et al.'s classification
(clinical stage ≤T2a, biopsy Gleason sum ≤6, and PSA ≤10 ng/ml), detected via multi (≥12)-core prostate biopsy were enrolled.
We reviewed patients preoperative and pathological data.
Results Among all subjects, 81 (39.9%) were upgraded to Gleason score ≥7 after RRP, whereas no downgrading was observed. In multivariate
analysis, only preoperative PSA level (P = 0.024) and number of positive cores (P = 0.027) were observed to be independent predictors of Gleason score upgrading following RRP. Also, Gleason core upgrading
was observed to be significantly associated with extraprostatic extension of tumor (P < 0.001) and positive surgical margin (P = 0.002).
Conclusions A significant proportion of patients with low-risk prostate cancer as defined by D’Amico et al.’s classification diagnosed
via multi-core prostate biopsy in contemporary period may have Gleason score upgrading following RRP. For patients with low-risk
prostate cancer, preoperative PSA level and number of positive cores may be useful predictors of Gleason score upgrading,
which was observed to significantly associated with other adverse pathologic features. 相似文献
75.
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77.
PURPOSE: Influenza vaccination has been recommended for all elderly people in The Netherlands since 1996, with greater than 80% compliance. It is unknown, however, if the addition of another vaccine to this immunization program will affect compliance. SUBJECTS AND METHODS: General practitioners offered a pneumococcal vaccine together with the yearly influenza vaccination to 3365 patients aged 65 years and older. A questionnaire was then mailed to a stratified sample (n = 972) of these patients. Factors associated with noncompliance with vaccination were assessed using polytomous logistic regression. RESULTS: A total of 2529 patients (75%) received the pneumococcal vaccine and 2812 (84%) received the influenza vaccine. Predictors of noncompliance with the pneumococcal vaccine were perceived lack of recommendation by the general practitioner (odds ratio [OR] = 4.6; 95% confidence interval [CI], 2.6 to 8.3) and fear of local side effects (OR = 2.8; 95% CI, 1.6 to 4.6). Predictors of noncompliance with both vaccinations also included unwillingness to comply with the doctor's advice (OR = 6.1; 95% CI, 2.4 to 15.4), the belief that vaccinations weaken one's natural defenses (OR = 2.7; 95% CI, 1.4 to 5.3) or that influenza is not dangerous (OR = 2.9; 95% CI, 1.5 to 5.4), and the fear of becoming sick from pneumococcal vaccination (OR = 2.9; 95% CI, 1.1 to 7.9). People who felt healthy, found it difficult to visit the doctor's office, had private medical insurance, or were younger than 75 years of age also had a greater risk of not being vaccinated. CONCLUSION: Introducing a pneumococcal vaccine to an existing influenza immunization program resulted in high pneumococcal and influenza vaccination rates. A wider diversity of patient characteristics and attitudes was present when neither vaccination was received. 相似文献
78.
Choi HJ Cho YM Moon MK Choi HH Shin HD Jang HC Kim SY Lee HK Park KS 《The Journal of clinical endocrinology and metabolism》2006,91(11):4657-4663
CONTEXT: Ghrelin is known to play a role in glucose metabolism and in beta-cell function. There are controversies regarding the role of ghrelin polymorphisms in diabetes and diabetes-related phenotypes. OBJECTIVE: The objective of this study was to examine polymorphisms of the ghrelin gene in a Korean cohort and investigate associations between them and susceptibility to type 2 diabetes and its related phenotypes. DESIGN AND PATIENTS: The ghrelin gene was sequenced to identify polymorphisms in 24 DNA samples. Common variants were then genotyped in 760 type 2 diabetic patients and 641 nondiabetic subjects. Genetic associations with diabetes-related phenotypes were also analyzed. RESULTS: Nine polymorphisms were identified, and four common polymorphisms [g.-1500C>G, g.-1062G > C, g.-994C > T, g.+408C > A (Leu72Met)] were genotyped in a larger study. The genotype distributions of these four common polymorphisms in type 2 diabetes patients were similar to those of normal nondiabetic controls. However, these four common polymorphisms were variably associated with several diabetes-related phenotypes, such as high-density lipoprotein (HDL) cholesterol, fasting plasma glucose, and homeostasis model assessment of insulin resistance. In particular, subjects harboring g.-1062C were associated with a lower serum HDL cholesterol level after adjusting for other variables (P = 0.0004 or 0.01 after Bonferroni correction for 24 tests). CONCLUSION: The aforementioned four common polymorphisms in the ghrelin gene were not found to be significantly associated with susceptibility to type 2 diabetes mellitus in the Korean population. However, the common polymorphism g.-1062G > C in the promoter region of the ghrelin gene was found to be significantly associated with serum HDL cholesterol levels. 相似文献
79.
Jin-Oh Choi Seung Woo Park Dae-Hee Shin Sung Hea Kim Wang-Soo Lee Hak Jin Kim Yoon Goo Kim Sang-Chol Lee Sang Hoon Lee 《Circulation journal》2007,71(5):669-674
BACKGROUND: The novel parameter T(E-E'), which is the time interval between the onset of the early diastolic mitral inflow velocity (E) and the early diastolic mitral annular velocity (E'), is reported to be related to the constant of the left ventricular (LV) relaxation, and T(E-E') is also reported to be useful for predicting the LV filling pressure. METHODS AND RESULTS: To investigate the effect of preload reduction via hemodialysis on T(E-E'), 28 pairs of echocardiographic evaluations were performed just before and immediately after hemodialysis, including the measurement of the T(E-E') as well as measurement of the conventional echocardiographic parameters. The baseline T(E-E') was 17.9 +/-28.1 ms, which correlated with the ratio of E/E' (r=0.49, p=0.008). After hemodialysis, T(E-E') was shortened to -3.2+/-34.1 ms, which was a significant change from baseline (p=0.001). CONCLUSIONS: As T(E-E') is a preload dependent parameter, the intravascular volume status should be taken into account when the clinical application of T(E-E') is considered as an index of LV relaxation. 相似文献
80.
Yang SK Yun S Kim JH Park JY Kim HY Kim YH Chang DK Kim JS Song IS Park JB Park ER Kim KJ Moon G Yang SH 《Inflammatory bowel diseases》2008,14(4):542-549
BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are considered rare diseases in developing countries. We have evaluated the incidence and prevalence of CD and UC over time in a district of Seoul, Korea. METHODS: A population-based study was performed from 1986 to 2005 in the Songpa-Kangdong district of Seoul. To recruit patients as completely as possible, multiple information sources, including all medical facilities in the study area and 3 referral centers nearby but outside the study area, were used. RESULTS: During the 20-year study period, 138 incident cases of CD (102 men, 36 women) and 341 incident cases of UC (170 men, 171 women) were identified. For the 20-year period, the adjusted mean annual incidence rates of CD and UC per 100,000 inhabitants were 0.53 (95% CI 0.44-0.62) and 1.51 (95% CI 1.34-1.67), respectively. When analyzed by 5-year intervals, the mean annual incidence rates of CD and UC increased significantly, from 0.05 and 0.34 per 100,000 inhabitants, respectively, in 1986-1990 to 1.34 and 3.08 per 100,000 inhabitants, respectively, in 2001-2005. The adjusted prevalence rates of CD and UC per 100,000 inhabitants on December 31, 2005, were 11.24 (95% CI 9.29-13.18) and 30.87 (95% CI 27.47-34.27), respectively. CONCLUSIONS: The incidence and prevalence of CD and UC in Seoul, Korea, are still low compared with those in Western countries, but are rapidly increasing. 相似文献