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排序方式: 共有3426条查询结果,搜索用时 31 毫秒
71.
72.
Different response to balloon angioplasty of carotid and coronary arteries: effects on acute platelet deposition and intimal thickening 总被引:4,自引:0,他引:4
Juan Jose Badimon Antonio Fernandez Ortiz Beat Meyer Alessandra Mailhac John T Fallon Erling Falk Lina Badimon James H Chesebro Valentin Fuster 《Atherosclerosis》1998,140(2):307-314
PTCA is a well-established intervention to reduce the severity of atherosclerotic coronary stenosis. Its primary success rate is seriously handicapped by the high incidence of late restenosis. Given the clinical and social importance of this proliferative process, new strategies are needed to prevent or reduce restenosis. Several animal models as well as different arteries have been used to study neointimal proliferation after arterial injury. A number of agents have shown to reduce neointimal proliferation after arterial injury in the carotids and iliac arteries of rodent models. Unfortunately, these results have not been replicated in humans. We have compared the acute and late response to vascular injury of the carotid and coronary arteries in the pig. Arterial injury was induced by performing balloon angioplasty of the carotid (elastic) and coronary (muscular) arteries in swine. Acute platelet-thrombus formation was evaluated by quantitation of Indium-labeled platelets deposited on the injured segments 1 h after procedure. Measurement of intimal area was performed by morphometry of the most stenotic cross-section at 28 days after balloon angioplasty. Platelet deposition after mild and severe injury in carotids (4±1 and 56±13×106 platelets/cm2, respectively) and coronaries (15±5 and 141±20×106 platelets/cm2, respectively) are significantly greater in deep, than in mild injury (P<0.005), and significantly greater in coronary than in carotid arteries after deep injury (P<0.05). Likewise, late neointima formation was significantly greater (P<0.05) after mild and severe injury in coronary (17±0.5 and 56 ±2%, respectively) than in carotid arteries (5±0.5 and 12±1%, respectively). Acute platelet-thrombus formation and late neointimal thickening are modulated by the degree of injury induced during the interventions; and after disruption of the internal elastic lamina, coronary arteries always had significantly more acute thrombus and neointimal thickening. This study emphasizes the importance of the animal species, the type of injury and the artery chosen for studies on restenosis post interventions. 相似文献
73.
OBJECTIVE: To perform clinical validation of the TM-2564G device for in-hospital blood pressure measurement according to the British Hypertension Society protocol. METHODS: The tests were carried out on 85 patients aged 19-82 years (41 male patients, mean age 50+/-19 years) with systolic blood pressure 75-219 mmHg and diastolic blood pressure 43-117 mmHg (mean 142+/-33/85+/-20 mmHg). For each patient, three readings of the TM-2564G device were compared with simultaneous auscultatory measurements by two trained independent observers. The observers used a mercury-calibrated sphygmomanometer and dual stethoscope. The results were graded according to the British Hypertension Society protocol 1993. RESULTS: The average difference was -1.85 mmHg for systolic blood pressure and -1.20 mmHg for diastolic blood pressure. The standard deviation of the difference between TM-2564G and the observers' results was 4.85 and 4.16 mmHg for systolic and diastolic blood pressures, respectively. Systolic blood pressure percentage of readings agreeing to within 5 mmHg was 75.7%, 10 mmHg 95.36% and 15 mmHg 99.6%, and for DBP 82.7, 97.6 and 99.8%, respectively. CONCLUSIONS: The TM-2564G device achieved A/A British Hypertension Society grade and can be recommended for in-hospital measurement of blood pressure. 相似文献
74.
Detection of central venous catheter‐related bloodstream infections in haematooncological patients
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75.
76.
Valentin Zumstein Marko Kraljević Annemarie Conzen Sebastian Hoechel Magdalena Müller-Gerbl 《Surgical and radiologic anatomy : SRA》2014,36(4):327-331
Purpose
Among late signs like sclerosis, cysts and osteophytes, alteration of cartilage is a common problem in osteoarthritis. To detect abnormal states in the glenohumeral joint, the physiologic distribution of the cartilage thickness must be known, which will allow physicians to better advise patients. High-resolution computed tomography (CT) data in soft tissue kernel provide highly accurate quantitative results and are a useful method to determine the geometrical situation of the glenohumeral joint. The objective of this study was to characterize the distribution of the thickness of the glenohumeral joint cartilage using CT.Methods
To investigate the distribution of thickness of the joint cartilage, CT images in soft tissue kernel of nine specimens were analyzed using image visualization software. Statistical analysis of the obtained data was performed using the ANOVA test.Results
Results showed different patterns in the glenoid cavity than in humeral head. Cartilage thickness in all glenoids showed maxima in the inferior and anterior portion, whereas central areas are covered with the thinnest cartilage layer. Maximum cartilage thickness in the humeral head was found in the central and superior parts.Conclusion
We could show that the distribution of cartilage thickness in the glenohumeral joint is not homogenous and that there exist several reproducible patterns. Evaluation of cartilage thickness in the glenohumeral joint is of high interest in basic and clinical research. 相似文献77.
Differential presentation of endogenous and exogenous hepatitis B surface antigens influences priming of CD8+ T cells in an epitope‐specific manner
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Petra Riedl Michael Reiser Katja Stifter Jana Krieger Reinhold Schirmbeck 《European journal of immunology》2014,44(7):1981-1991
Little is known about whether presentation of endogenous and exogenous hepatitis B virus (HBV) surface antigens on APCs targeted by vaccination and/or virus‐harboring hepatocytes influences de novo priming of CD8+ T cells. We showed that surface antigen‐expressing transfectants exclusively display a Kb/S190 epitope, whereas cells pulsed with recombinant surface particles (rSPs) exclusively present a Kb/S208 epitope to CD8+ T cells. The differential presentation of these epitopes largely reflects the selective, but not exclusive, priming of Kb/S190‐ and Kb/S208‐specific T cells in C57BL/6 mice by endogenous/DNA‐ or exogenous/protein‐based vaccines, respectively. Silencing the Kb/S190 epitope (Kb/S190V194F) in antigen‐expressing vectors rescued the presentation of the Kb/S208 epitope in stable transfectants and significantly enhanced priming of Kb/S208‐specific T cells in C57BL/6 mice. A Kb/S190‐mediated immunodominance operating in surface antigen‐expressing cells, but not in rSP‐pulsed cells, led to an efficient suppression in the presentation of the Kb/S208 epitope and a consequent decrease in the priming of Kb/S208‐specific T cells. This Kb/S190‐mediated immunodominance also operated in 1.4HBV‐Smut transgenic (tg) hepatocytes selectively expressing endogenous surface antigens and allowed priming of Kb/S208‐ but not Kb/S190‐specific T cells in 1.4HBV‐Smut tg mice. However, IFN‐γ+ Kb/S208‐specific T cells could not inhibit HBV replication in the liver of 1.4HBV‐Smut tg mice. These results have practical implications for the design of T‐cell‐stimulating therapeutic vaccines. 相似文献
78.
79.
Valentin Wiedemeyer Moritz Berger Markus Martini Franz-Josef Kramer Nils Heim 《Journal of cranio-maxillo-facial surgery》2019,47(10):1504-1509
IntroductionAngle Class II malocclusion due to mandibular retrognathia is a common dentofacial deformity. It is well known that mandibular advancement increases pharyngeal airway dimensions. The aim of this study was to evolve a mathematical method for predicting posterior pharyngeal airway space (PAS) changes based on 2D lateral cephalographic radiographs (LCRs) and expected extent of mandibular advancement prior to BSSO.Materials and methodsLinear regression analyses were performed in order to investigate the relation between the posterior airway space and mandibular advancement. LCRs where carried out to assess skeletal landmarks and pharyngeal airway space pre- (T0) and postoperatively (T1). To detect changes postoperatively, the posterior airway space was divided into three units: nasopharyngeal airway space (superior airway space — SPAS), oropharyngeal airway space (mid airway space — MAS) and hypopharyngeal airway space (inferior airway space — IAS). The differences between the distances of distinct measurement points (DIFF) were measured pre- and postoperatively. DOA referred to the distance of mandibular advancement and DP to the distance between the measurement points preoperatively. The parameters a, b1 and b2 were the regression coefficients that were determined separately for each unit (SPAS, MAS, and IAS).Results49 patients (16 male and 33 female) with a mean age of 27.2 years (SD: 10.09), ranging from 18 to 51 years, who underwent mandibular advancement surgery (BSSO) were enrolled in this study. The mean distance of mandibular advancement was 5.05 mm (SD: 1.63). Regarding SPAS and IAS, mandibular advancement did not affect dimensions significantly: SPAS DIFF, 0.33 mm ± 1.13 mm (b1, p = 0.0881; b2, p = 0.087); IAS DIFF, 0.66 mm ± 2.45 mm (b1, p = 0.342; b2, p = 0.765). DOA and DP did not influence DIFF significantly in both sections. Regarding MAS, the mean effect of mandibular advancement was an expansion of 2.47 mm ± 2.24. The linear regression model showed a statistically significant (b1, p = 0.0064; b2, p = 0.0240) influence of DOA and DP on DIFF in posterior airway dimensions pre- and postoperatively.DiscussionBased on preoperative LCR imaging data, a linear regression model was developed as a mathematical approach to allow prediction of PAS development in patients with Angle Class II malocclusions of different degrees. Increasing mandibular advancement was shown to be linked to increasing PAS, while a greater distance between the measuring points preoperatively led to smaller predicted PAS increases postoperatively.ConclusionPredicting pharyngeal airway space (PAS) development after mandibular advancement by analysing lateral cephalometric radiographs (LCR) may be useful in the screening and treatment of obstructive sleep apnea syndrome (OSAS) patients. Our mathematical approach is a simple and sustainable prediction tool based on LTR data for patients with Class II malocclusions. 相似文献
80.
Felix Aberer MD Peter N. Pferschy MSc Norbert J. Tripolt PhD Caren Sourij MD Anna M Obermayer MD Florian Prüller MD Eva Novak MD Philipp Reitbauer Harald Kojzar BSc Barbara Prietl PhD Selina Kofler BSc Martina Brunner MSc Eva Svehlikova MD Tatjana Stojakovic MD Hubert Scharnagl MD Abderrahim Oulhaj PhD Faisal Aziz Msc Regina Riedl PhD Harald Sourij MD 《Diabetes, obesity & metabolism》2020,22(2):212-221