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排序方式: 共有2950条查询结果,搜索用时 15 毫秒
961.
Apel D Jakobs R Benz C Martin WR Riemann JF 《Italian journal of gastroenterology and hepatology》1999,31(9):876-879
A 75-year-old man with right upper quadrant abdominal pain was diagnosed by gastroscopy to have an impacted gallstone in the duodenal bulb. Using the polypectomy loop, the stone was extracted from the bulbus and mobilized into the stomach. After failure to remove the stone from the stomach as well as fragmentation by mechanical lithotripsy, electrohydraulic lithotripsy was used to break up the stone, parts of which passed spontaneously through the bowel. Thus, it was unnecessary to proceed with surgical enterolithotomy to remove, from the duodenal bulb, the impacted gallstone responsible for the gastric outlet obstruction. 相似文献
962.
Barbash IM Halperin P Rot A Hod H Barbash GI 《Journal of thrombosis and thrombolysis》1998,6(3):207-209
The baseline characteristics and outcome of patients with acute chest pain who were brought to the hospital by public versus private mobile intensive care units were compared. Of 283 patients brought to the Department of Emergency Medicine at the Tel Aviv Sourasky Medical Center by mobile units in July and September of 1995, 163 were transported by the private service and 120 by the public service. Patients who were brought by the private service were older and had significantly more comorbidities, especially cardiac history. However, a significantly higher proportion of patients brought by the public service suffered confirmed myocardial infarction, and were hospitalized in the intensive coronary care unit. In addition, mortality in this group was significantly higher (4.0% vs. 2.2%). Possible explanations for this finding are greater accessibility or bias in the prehospital management of patients channeled through the private mobile service. 相似文献
963.
J M Mallion D Arie J L Debru H Morena B Denis G Cau 《Archives des maladies du coeur et des vaisseaux》1979,72(8):868-873
The results of continuous 12-hour electrocardiography in 40 convalescent patients after myocardial infarction undergoing a programme of readaptation on average 4 weeks after the initial infarction are reported. The frequency and alarming nature of the VES observed in 75% patients who had already undergone selection for the coronary readaptation programme, 30% of whom were receiving antiarrhythmic therapy, is emphasized. The observation of a progressive increase in the number of VES during the day prompts the following suggestions: the possibility of limited continuous ECG monitoring at the end of the day, the need to adapt the dosage of antiarrhythmic drugs during this most critical period. The comparison of the results of continuous ECG with those of repeated exercise ECG seems very positive, but some reservations are made and it would seem logical to associate these two complementary methods of investigation. 相似文献
964.
Garnaas MK Moodie KL Liu ML Samant GV Li K Marx R Baraban JM Horowitz A Ramchandran R 《Circulation research》2008,103(7):710-716
Rho GTPases play an important and versatile role in several biological processes. In this study, we identified the zebrafish ortholog of the mammalian Rho A guanine exchange factor, synectin-binding guanine exchange factor (Syx), and determined its in vivo function in the zebrafish and the mouse. We found that Syx is expressed specifically in the vasculature of these organisms. Loss-of-function studies in the zebrafish and mouse point to a specific role for Syx in angiogenic sprouting in the developing vascular bed. Importantly, vasculogenesis and angioblast differentiation steps were unaffected in syx knockdown zebrafish embryos, and the vascular sprouting defects were partially rescued by the mouse ortholog. Syx knockdown in vitro impairs vascular endothelial growth factor-A-induced endothelial cell migration and angiogenesis. We have also uncovered a potential mechanism of endothelial sprout guidance in which angiomotin, a component of endothelial cell junctions, plays an additive role with Syx in directing endothelial sprouts. These results identify Syx as an essential contributor to angiogenesis in vivo. 相似文献
965.
STUDY OBJECTIVES: To explore the role of respiratory interactive computer games in teaching spirometry to preschool children, and to examine whether the spirometry data achieved are compatible with acceptable criteria for adults and with published data for healthy preschool children, and whether spirometry at this age can assess airway obstruction. DESIGN: Feasibility study. SETTINGS: Community kindergartens around Israel and a tertiary pediatric pulmonary clinic. PARTICIPANTS: Healthy and asthmatic preschool children (age range, 2.0 to 6.5 years). INTERVENTION: Multi-target interactive spirometry games including three targets: full inspiration before expiration, instant forced expiration, and long expiration to residual volume. MEASUREMENTS AND RESULTS: One hundred nine healthy and 157 asthmatic children succeeded in performing adequate spirometry using a multi-target interactive spirometry game. American Thoracic Society (ATS)/European Respiratory Society spirometry criteria for adults for the start of the test, and repeatability were met. Expiration time increased with age (1.3 +/- 0.3 s at 3 years to 1.9 +/- 0.3 s at 6 years [+/- SD], p < 0.05). FVC and flow rates increased with age, while FEV1/FVC decreased. Healthy children had FVC and FEV1 values similar to those of previous preschool studies, but flows were significantly higher (> 1.5 SD for forced expiratory flow at 50% of vital capacity [FEF50] and forced expiratory flow at 75% of vital capacity [FEF75], p < 0.005). The descending part of the flow/volume curve was convex in 2.5- to 3.5-year-old patients, resembling that of infants, while in 5- to 6-year-old patients, there was linear decay. Asthma severity by Global Initiative for Asthma guidelines correlated with longer expiration time (1.7 +/- 0.4 s; p < 0.03) and lower FEF50 (32 to 63%; p < 0.001) compared to healthy children. Bronchodilators improved FEV1 by 10 to 13% and FEF50 by 38 to 56% of baseline. CONCLUSIONS: Interactive respiratory games can facilitate spirometry in very young children, yielding results that conform to most of the ATS criteria established for adults and published data for healthy preschool children. Spirometric indexes correlated with degree of asthma severity. 相似文献
966.
967.
Steinvil A Fireman E Wolach O Rebhun U Cohen M Shapira I Berliner S Rogowski O 《Respiratory medicine》2008,102(6):919-926
BACKGROUND: Ethnic origin affects spirometric prediction values. Our aims were to investigate the effect of ethnic origin on prediction equations in an immigrant-based society, identify possible deviations from commonly used prediction equations and analyze the effect of miscalculation in a large cohort of apparently healthy individuals. METHODS: Healthy never-smokers participants from a large Israeli survey underwent lung function testing and were divided into two major ethnic groups: Ashkenazi Jews (AJ) and Sephardic Jews (SJ). Data were analyzed by multiple linear regressions. Forced vital capacity (FVC), forced expiratory volume in 1s (FEV1) and the FEV1/FVC ratio were measured according to ERS-ATS guidelines. RESULTS: The study population comprised 3150 individuals (AJ=1817; SJ=1333). AJ tended to be older and taller than SJ (all p<0.005). Ethnicity entered as a significant regression variable for FVC for both genders and for FEV1 for females only. The final regression model for both FVC and FEV1 had R2=0.71 and the standard error of the estimate (SEE) for FVC and FEV1 were 0.54 and 0.43 L, respectively. The regression model for the FEV1/FVC ratio has less statistical strength (R2=0.06, SEE=6.15%). We found statistically significant underestimates of predicted lung volumes from the commonly used prediction equation for each ethnic group. CONCLUSIONS: Ashkenazi and Sephardic Jews have different ranges of normal pulmonary function values. Lung function prediction equations in an immigrant-based society should be based on local and not previously reported regional equations and adjusted for ethnic attributed variance. 相似文献
968.
Pacemaker current (I(f)) in the human sinoatrial node. 总被引:1,自引:0,他引:1
Arie O Verkerk Ronald Wilders Marcel M G J van Borren Ron J G Peters Eli Broekhuis Kayan Lam Ruben Coronel Jacques M T de Bakker Hanno L Tan 《European heart journal》2007,28(20):2472-2478
AIMS: Animal studies revealed that the hyperpolarization-activated pacemaker current, I(f), contributes to action potential (AP) generation in sinoatrial node (SAN) and significantly determines heart rate. I(f) is becoming a novel therapy target to modulate heart rate. Yet, no studies have demonstrated that I(f) is functionally present and contributes to pacemaking in human SAN. We aimed to study I(f) properties in human SAN. METHODS AND RESULTS: In a patient undergoing SAN excision, we identified SAN using epicardial activation mapping. From here, we isolated myocytes and recorded APs and I(f) using patch-clamp techniques. Pacemaker cells generated spontaneous APs (cycle length 828 +/- 15 ms) following slow diastolic depolarization, maximal diastolic potential - 61.7 +/- 4.3 mV, and maximal AP upstroke velocity 4.6 +/- 1.2 V/s. They exhibited an hyperpolarization-activated inward current, blocked by external Cs(+) (2 mmol/L), characterizing it as I(f). Fully-activated conductance was 75.2 +/- 3.8 pS/pF, reversal potential - 22.1 +/- 2.4 mV, and half-maximal activation voltage and slope factor of steady-state activation - 96.9 +/- 2.7 and - 8.8 +/- 0.5 mV. Activation time constant ranged from approximately 350 ms (-130 mV) to approximately 1 s (-100 mV), deactivation time constant 156 +/- 45 ms (-40 mV). The role of I(f) in pacemaker activity was demonstrated by slowing of pacemaker cell diastolic depolarization and beating rate by Cs(+). CONCLUSION: I(f) is functionally expressed in human SAN and probably contributes to pacemaking in human SAN. 相似文献
969.
Span LF Vierwinden G Pennings AH Boezeman JB Raymakers RA de Witte T 《Experimental hematology》2005,33(4):435-442
OBJECTIVE: Bone marrows (BM) of myelodysplastic syndrome (MDS) patients show increased proliferation and premature programmed cell death (PCD) in vivo as well as in vitro. We explored the proliferative capacity and apoptotic propensity of CD34+ progenitor cells of MDS patients excluding accessory cell interference. MATERIALS AND METHODS: CD34+/CD3-/CD19- cells of 5 MDS patients and 5 normal BM were sorted as single cells into single wells and were cultured in liquid medium. Wells were evaluated on days 4, 7, 10, and 14. PCD was determined by staining with annexin V-FITC. Growth rate and cell doubling time (Td) were calculated for each colony-forming cell. RESULTS: Normal BM CD34+ cells formed clusters and colonies and both showed increasing PCD in time, although within colonies the degree of apoptosis was twice as high (about 25%) as compared with clusters at all time points. In MDS increased cluster formation was observed at all evaluation points when compared to normal BM, whereas the number of colonies was markedly reduced (1/7 of normal). These colonies were also smaller, usually smaller than 100 cells. Significantly enhanced levels of PCD of clusters (53-79%) in combination with longer cell doubling times explain this slower formation of smaller colonies. Surprisingly, these colonies showed considerably lower levels of PCD (7-32%) as compared to normal (1-48%, median values). CONCLUSIONS: In the absence of stromal influences and accessory cells, this study in MDS patients showed intrinsically enhanced proliferation and apoptosis of cluster-forming cells, as the opposite was true for colony-forming cells. 相似文献
970.
Roos F.J. Marsman Connie R. Bezzina Fabian Freiberg Arie O. Verkerk Michiel E. Adriaens Svitlana Podliesna Chen Chen Bettina Purfürst Bastian Spallek Tamara T. Koopmann Istvan Baczko Cristobal G. dos Remedios Alfred L. George Jr. Nanette H. Bishopric Elisabeth M. Lodder Jacques M.T. de Bakker Robert Fischer Ruben Coronel Arthur A.M. Wilde Michael Gotthardt Carol Ann Remme 《Journal of the American College of Cardiology》2014