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11.
First results are presented to determine the maturity of fetal lung by sonography. Using the fetal liver as a reference-organ we are avoiding the known pitfalls which made it impossible in the past to standardize the fetal lung changes depending on the age of gestation. We examined 104 patients between week 27 and week 41. In one ultrasound section cut we depicted as well lung and liver. According to the known A-mode we registered frequencies in both organs. The registered frequencies were entered digitally into a computer and checked for f(mean), f(max) and f(min). Afterwards the frequencies of the lung were divided by those of the liver. Of all weeks of gestation the mean value and standard deviation were calculated. We found the liver as an adequate reference-organ, since there is no change of the reflection pattern between the different weeks of gestation, while there are significant changes to be registered in the fetal lung, a cutting line being week 35. A quotient of f(mean) lower than 1.1 hints to lung maturity while values over 1.1 point to immaturity. This was confirmed by several cases of analysis of amniotic fluid (L/S-ratio). Further comparisons with amniotic fluid results will have to validate these findings. 相似文献
12.
Desirability of an action, often referred to as utility or value, is determined by various factors, such as the probability and timing of expected reward. We investigated how performance of monkeys in an oculomotor serial reaction time task is influenced by multiple motivational factors. The animals produced a series of visually-guided eye movements, while the sequence of target locations and the location of the rewarded target were systematically manipulated. The results show that error rates as well as saccade latencies were consistently influenced by the number of remaining movements necessary to obtain a reward. In addition, when the animal produced multiple saccades before fixating a given target, the first saccade tended to be directed towards the rewarded location, suggesting that saccades to rewarded location and visual target might be programmed concurrently. These results show that monkeys can utilize information about the required sequence of movements to update their subjective values. 相似文献
13.
Y.W. Chung D.S. Han Y.K. Park B.K. Son C.H. Paik Y.C. Jeon J.H. Sohn 《Digestive and liver disease》2006,38(7):515-517
A diospyrobezoar is a type of phytobezoar that is considered to be harder than any other types of phytobezoars. Here, we describe a new treatment modality, which effectively and easily disrupted huge gastric diospyrobezoars. A 41-year-old man with a history of diabetes mellitus was admitted with lower abdominal pain and vomiting. Upper gastrointestinal endoscopy revealed three huge, round diospyrobezoars in the stomach. He was made to drink two cans of Coca-Cola every 6 h. At endoscopy the next day, the bezoars were partially dissolved and turned to be softened. We performed direct endoscopic injection of Coca-Cola into each bezoar. At repeated endoscopy the next day, the bezoars were completely dissolved. 相似文献
14.
Mun Su Kang Dong Il Park Jung Ho Park Hong Joo Kim Yong Kyun Cho Chong Il Sohn Woo Kyu Jeon Byung Ik Kim 《Taehan Sohwagi Hakhoe chi》2006,48(6):395-400
BACKGROUND/AIMS: Bamboo joint-like (BJL) appearance is an endoscopic finding characterized by swollen longitudinal folds transversed by erosive fissures or linear furrows on the lesser curvature side of gastric body and cardia. It has been reported to be associated with Crohn's disease (CD). This study was aimed to evaluate the incidence of BJL appearance in Korean patients with CD. METHODS: From January to December in 2005, we performed esophagogastroduodenoscopy (EGD) in patients diagnosed as CD and ulcerative colitis (UC) in our hospital. Non-inflammatory bowel disease (IBD) subjects with upper gastrointestinal symptoms who underwent EGD were consecutively enrolled during the same period. One endoscopist performed all the endoscopic examinations to avoid inter-observer variation. A dye-spraying technique with 0.4% indigocarmine was used to allow the detection of subtle changes during the endoscopic examination. RESULTS: A total of 21 patients with CD (mean age+/-SD, 40+/-15 yr; M/F, 13/8), 28 patients with UC (42+/-15 yr; 21/7), and 685 non-IBD subjects (49+/-14 yr; 354/331) were enrolled. EGD findings in CD patients were gastric erosions (11/21), chronic superficial gastritis (5/21), chronic atrophic gastritis (1/21), duodenal erosions or ulcers (2/21), and normal (2/21). Incidence of BJL appearance was significantly higher in patients with CD (47.6%, 10/21) than others (UC, 3.6%, 1/28; non-IBD, 0.1%, 1/685) (p< 0.0001). Among patients with CD, incidence of BJL appearance was not significantly different according to the sex, status of H. pylori infection, Vienna classification for phenotype, medications or EGD findings. CONCLUSIONS: BJL appearance on the gastric body and cardia can be a diagnostic clue to CD. 相似文献
15.
Kwan Chang Kim Kwang Ree Cho Yong-Jin Kim Dae-Won Sohn Ki-Bong Kim 《European journal of cardio-thoracic surgery》2007,31(2):261-266
OBJECTIVE: We evaluated the long-term results of the Cox-Maze III procedure (CM-III) for persistent atrial fibrillation (AF) associated with rheumatic mitral valve (MV) disease. METHODS: We analyzed 127 patients who underwent the CM-III combined with a rheumatic MV procedure between 1994 and 2004. In-hospital mortalities were excluded from the study. RESULTS: There were 10 late deaths and the mean follow-up duration was 7.1+/-2.8 years (range, 13 months to 11.5 years). Normal sinus rhythm was restored in 88.2% (112/127) after the CM-III. Right atrial contractility was demonstrable in 100% (112/112) and left atrial contractility in 68.8% (77/112) of the patients restored to sinus rhythm. Fifteen patients never regained sinus rhythm after the CM-III (AF treatment failure). Permanent pacemakers were implanted in 4.7% (6/127) of the patients during the follow-up. Late recurrence of AF developed in 34 of 112 patients at 44+/-27 months postoperatively, and sinus rhythm was restored in 29 of 34 patients by administration of an antiarrhythmic medication. Independent risk factors for late AF recurrence were longer duration of AF (>60 months) (odds ratio (OR)=2.758, p=0.025), increased left atrial size (OR=1.113, p=0.004). Freedom from AF recurrence was 93% at 1-year, 82% at 3 years, 71% at 5 years, and 63% at 7 years. Risk factors for AF treatment failure were longer duration of AF (>60 months) (p<0.001) and increased patient age (p=0.030). A higher prevalence of significant late tricuspid regurgitation was observed in patients with AF treatment failure and those with late AF recurrence. CONCLUSIONS: The CM-III for persistent AF associated with rheumatic MV disease demonstrated a progressively decreased cure rate during the follow-up period. Early surgical therapy, aggressive left atrial reduction, and correction of tricuspid regurgitation at the time of surgery may increase the long-term success rate. 相似文献
16.
Cumhur Kiliner Serkan Inceoglu Moon Jun Sohn Lisa A. Ferrara Edward C. Benzel 《Journal of clinical neuroscience》2007,14(12):1186-1191
We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength. 相似文献
17.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
18.
Inhibition of 2-nitropropane-induced rat liver DNA and RNA damage by benzyl selenocyanate 总被引:5,自引:2,他引:3
We observed that pretreatment of male F344 rats with benzyl selenocyanate,
a versatile organoselenium chemopreventive agent in several animal model
systems, decreases the levels of DNA and RNA modifications produced in the
liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms
involved, we pretreated male F344 rats with either benzyl selenocyanate,
its sulfur analog benzyl thiocyanate, phenobarbital or cobalt
protoporphyrin IX; the latter is a depletor of P450. We then determined (1)
the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on
2-nitropropane- induced liver DNA and RNA modifications and (3) amount of
nitrate excreted in rat urine following administration of the carcinogen.
Pretreatment with benzyl selenocyanate or phenobarbital increased the
denitrification activity of liver microsomes by 217 and 765%, respectively,
increased liver P4502B1 by 31- and 435-fold, respectively, decreased the
levels of 2-nitropropane-induced modifications in liver DNA (29-70% and
17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and
increased the 24-h urinary excretion of nitrate by 157 and 209%,
respectively. Pretreatment with benzyl thiocyanate had no significant
effect on any of these parameters. Pretreatment with cobalt protoporphyrin
IX decreased liver P4502B 1 by 87%, decreased the denitrification activity
of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate
by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic
acid modifications by 17-67%. These results indicate that the metabolic
sequence from 2-nitropropane to the reactive species causing DNA and RNA
modifications does not involve the removal of the nitro group. Moreover,
they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic
acid modifications in part by increasing its detoxication through induction
of denitrification, although it is evident that other mechanisms must also
be involved.
相似文献
19.
Gi-Young Park Jong-Min Kim Sung-Il Sohn Im-Hee Shin Michael Y Lee 《Journal of rehabilitation medicine》2007,39(7):526-530
OBJECTIVE: To evaluate the ultrasonographic measurement of shoulder subluxation in patients with post-stroke hemiplegia. DESIGN: Prospective, single blind study. PATIENTS: A total of 41 patients with post-stroke hemiplegia were included (24 men and 17 women, mean age 56 years (standard deviation 11), age range 34-78 years). METHODS: Clinical evaluation of the affected shoulder was assessed using the Motricity Index scores and the Modified Ashworth Scale. Two ultrasonographic measurements were taken to check intra-rater reliability. The shoulder subluxation ratio was determined as the ratio of the radiographic vertical and horizontal distance, and the ultrasonographic lateral and anterior distances in the affected shoulder divided by that in the unaffected shoulder. RESULTS: Intraclass correlation coefficients of the repeated ultrasonographic lateral/anterior distance measurements in the unaffected and affected shoulders were 0.979/0.969 and 0.950/0.947, respectively. Ultrasonographic lateral/anterior distance ratios were negatively correlated with Motricity Index scores of the affected shoulder abduction (r = -0.490, p < 0.001/ r = -0.671, p < 0.001). Ultrasonographic anterior distance ratio was negatively correlated with Modified Ashworth Scale score of the affected shoulder (r = -0.374, p < 0.05). However, there was no correlation between radiographic distance ratios and clinical evaluation scores. CONCLUSION: We strongly recommend ultrasonography as a diagnostic tool to measure the degree of shoulder subluxation in patients with post-stroke hemiplegia. 相似文献
20.