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排序方式: 共有642条查询结果,搜索用时 15 毫秒
101.
Joachim Knopp 《Virchows Archiv : an international journal of pathology》1957,330(2):125-138
Zusammenfassung Es wird über eine Appendix vermiformis berichtet, mit chronisch rezidivierender obliterierender Entzündung, Perforation in das Mesenteriolum, Mucocele und geringgradig ausgeprägter Myxoglobulose.Gleichzeitig bestehende, von intakter Mucosa ausgekleidete, fast achsenparallele, bis 3 cm lange Kanäle werden nicht als erworbene falsche innere und äußere Divertikel bezeichnet, sondern als rudimentäre, von der Spitze ausgehende Mehrfachbildungen der Appendix gedeutet.Zwei größere im Mesenteriolum gelegene Perforationshöhlen werden auf Grund ihrer Wandbeschaffenheit als cystische Schleimgranulome mit mesenchymalen Fremdkörperriesenzellen bezeichnet.Die Innenauskleidung der Mucocele besteht in der Appendixspitze vorwiegend aus vielkernigen epithelialen Riesenzellen. Beginnende Penetrationserscheinungen in der Wand des gemeinsamen Spitzenstückes der zusätzlichen Lumina lassen den Befund als Vorstadium des Pseudomyxoma peritonei bei Mucocele deuten. 相似文献
102.
Diffusional arteriovenous shunting in the heart 总被引:2,自引:0,他引:2
Previous indicator dilution experiments in isolated blood-perfused dog hearts suggested that there was intramyocardial diffusional shunting of water relative to a flow-limited solute, antipyrine. Two sets of studies have been done to assess the importance of this shunting, since it implies the possibility of a diffusional bypass for oxygen and other substances, which may be important in ischemia. Nonconsumed tracers were used to show the phenomenon. In the first set, bolus injections of 133Xe dissolved in saline were made into the coronary inflow and the tracer content of the organ recorded by an external gamma detector. The initial Xe washout was disproportionately rapid at low flows, and the late phase was also relatively retarded. In the second set, boluses of cool saline containing indocyanine green were injected into the coronary arterial inflow while coronary sinus outflow dilution curves were recorded via a thermistor and a dye densitometer over a wide range of flows. The thermal curves showed emergence of heat preceding the dye; the degree of precession was much greater at low flows, and, unlike the dye curves, the thermal dilution curves showed dramatic differences in shape at different flows. A model for diffusional countercurrent exchange shows similar changes in residue curves and outflow dilution curves. The conclusion is that there is diffusional shunting of small lipid-soluble molecules whose diffusion coefficients in tissue are high. While the shunting of heat is great, the shunting of soluble gases will not be large and that of normal substrates will be negligible. 相似文献
103.
104.
Knopp RH Fish B Dowdy A Retzlaff B Walden C Rusanu I Paramsothy P 《Current atherosclerosis reports》2006,8(6):492-500
A low-fat diet is recommended for hyperlipidemia. However, low-density lipoprotein (LDL) responses depend on the type of hyperlipidemia
(ie, simple hypercholesterolemia or combined hyperlipidemia). In combined hyperlipidemia, which is typical of patients with
metabolic syndrome, LDL levels are only one third as responsive to fat and cholesterol as simple hypercholesterolemia. The
diminished dietary sensitivity of combined hyperlipidemia is explained by diminished intestinal absorption of cholesterol,
a feature of metabolic syndrome. In turn, combined hyperlipidemia is caused by heightened lipid secretion by the liver. A
moderate-fat, moderate-carbohydrate diet employing allowable fats has the promise of reducing endogenous lipoprotein production
in combined hyperlipidemia. Triglyceride, LDL, and small-dense LDL should be lower, and high-density lipoprotein, apoprotein
A-I, and buoyant LDL should be higher. A test of this dietary strategy on lipoproteins and downstream benefits on inflammatory
mediators, oxidative stress, and vascular reactivity is now underway. 相似文献
105.
Rozenn N. Lemaitre Irena B. King Thomas D. Rea Kenneth M. Rice Robert H. Knopp Michael K. Copass 《Metabolism: clinical and experimental》2009,58(4):534-1514
Higher levels of long-chain n-3 polyunsaturated fatty acids in red blood cell membranes are associated with lower risk of sudden cardiac arrest. Whether membrane levels of α-linolenic acid, a medium-chain n-3 polyunsaturated fatty acid, show a similar association is unclear. We investigated the association of red blood cell membrane α-linolenic acid with sudden cardiac arrest risk in a population-based case-control study. Cases, aged 25 to 74 years, were out-of-hospital sudden cardiac arrest patients attended by paramedics in Seattle, WA (n = 265). Controls, matched to cases by age, sex, and calendar year, were randomly identified from the community (n = 415). All participants were free of prior clinically diagnosed heart disease. Blood was obtained at the time of cardiac arrest (cases) or at the time of an interview (controls). Higher membrane α-linolenic acid was associated with a higher risk of sudden cardiac arrest: after adjustment for matching factors and smoking, diabetes, hypertension, education, physical activity, weight, height, and total fat intake, the odds ratios corresponding to increasing quartiles of α-linolenic acid were 1.7 (95% confidence interval [CI], 1.0-3.0), 1.9 (95% CI, 1.1-3.3), and 2.5 (95% CI, 1.3-4.8) compared with the lowest quartile. The association was independent of red blood cell levels of long-chain n-3 fatty acids, trans-fatty acids, and linoleic acid. Higher membrane levels of α-linolenic acid are associated with higher risk of sudden cardiac arrest. 相似文献
106.
Pathmaja Paramsothy Robert Knopp Michael Y. Tsai Susan R. Heckbert 《Metabolism: clinical and experimental》2009,58(2):212-219
We have asked whether the prevalence of combined hyperlipidemia (CHL) differs by race/ethnicity, obesity, and insulin resistance in a contemporary, multiethnic, US cohort. We determined the prevalence and adjusted odds of CHL in a cohort of 5923 men and women free of clinically recognized cardiovascular disease and diabetes according to race/ethnicity (white, Chinese, African American, and Hispanic), obesity, and insulin resistance. Untreated lipid values were imputed for those on lipid-lowering therapy. Combined hyperlipidemia was defined using age- and sex-specific greater than or equal to 75th percentile cut points for low-density lipoprotein cholesterol and triglycerides obtained from a predominantly white North American population study. Compared with whites, adjusted odds ratios for CHL were 0.48 in African Americans (95% confidence interval [CI], 0.30-0.75), 1.33 in Hispanics (95% CI, 0.93-1.91), and 1.06 in Asians (95% CI, 0.62-1.82). Within the entire population, the adjusted odds of CHL were over 2-fold higher in overweight and obese participants compared with normal-weight participants and more than 4-fold higher in quartiles 2 through 4 of insulin resistance compared with quartile 1. African Americans had lower odds for CHL than whites despite higher body mass index and abdominal adiposity. Hispanics had a nonsignificantly higher trend, and Asians had no significantly different odds than whites. Modest increases in weight and insulin resistance were associated with significantly higher odds of CHL in a multiethnic US population. Further research is needed to determine the most efficacious diet, exercise, and drug management to decrease the risk of CHL and coronary heart disease among racial/ethnic groups in the United States. 相似文献
107.
OBJECTIVE: Cardiovascular disease (CVD) risk is increased in type 2 diabetes. The purpose of this study was to assess the effect of 10 mg of atorvastatin versus placebo on CVD prevention in subjects with type 2 diabetes and LDL cholesterol levels below contemporary guideline targets. RESEARCH DESIGN AND METHODS: Subjects were randomly assigned to receive 10 mg of atorvastatin or placebo in a 4-year, double-blind, parallel-group study. The composite primary end point comprised cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, recanalization, coronary artery bypass surgery, resuscitated cardiac arrest, and worsening or unstable angina requiring hospitalization. RESULTS: A total of 2,410 subjects with type 2 diabetes were randomized. Mean LDL cholesterol reduction in the atorvastatin group over 4 years was 29% versus placebo (P < 0.0001). When we compared atorvastatin versus placebo, composite primary end point rates were 13.7 and 15.0%, respectively (hazard ratio 0.90 [95% CI 0.73-1.12]). In the subset of 1,905 subjects without prior myocardial infarction or interventional procedure, 10.4% of atorvastatin- and 10.8% of placebo-treated subjects experienced a primary end point (0.97 [0.74-1.28]). In the 505 subjects with prior myocardial infarction or interventional procedure, 26.2% of atorvastatin- and 30.8% of placebo-treated subjects experienced a primary end point (0.82 [0.59-1.15]). Relative risk reductions in fatal and nonfatal myocardial infarction were 27% overall (P = 0.10) and 19% (P = 0.41) and 36% (P = 0.11) for subjects without and with prior myocardial infarction or interventional procedure, respectively. CONCLUSIONS: Composite end point reductions were not statistically significant. This result may relate to the overall study design, the types of subjects recruited, the nature of the primary end point, and the protocol changes required because of changing treatment guidelines. For these reasons, the results of the Atorvastatin Study for Prevention of Coronary Heart Disease Endpoints in Non-Insulin-Dependent Diabetes Mellitus (ASPEN) did not confirm the benefit of therapy but do not detract from the imperative that the majority of diabetic patients are at risk of coronary heart disease and deserve LDL cholesterol lowering to the currently recommended targets. 相似文献
108.
Giesel FL Bischoff H von Tengg-Kobligk H Weber MA Zechmann CM Kauczor HU Knopp MV 《Chest》2006,129(6):1570-1576
STUDY OBJECTIVE: Dynamic contrast-enhanced MRI (DCE-MRI) followed by pharmacokinetic analysis has been successfully used in a variety of solid tumors. The aims of this study were to evaluate the feasibility of DCE-MRI in malignant pleural mesothelioma (MPM), to differentiate benign from pathologic tissue and compare pharmacokinetic with clinical parameters and survival in order to map out its microcirculation; and to compare pharmacokinetic with clinical parameter and survival in order to improve our understanding of the in vivo biology of this malignancy. METHODS: Nineteen patients with a diagnosis of MPM who were scheduled to receive chemotherapy with gemcitabine were enrolled in the study. DCE-MRI was performed before treatment (n = 19) and after the third cycle (n = 12) and sixth cycle (n = 7) of chemotherapy. An established pharmacokinetic two-compartment model was used to analyze DCE-MRI. Tumor regions were characterized by the pharmacokinetic parameters amplitude (Amp), redistribution rate constant (kep), and elimination rate constant (kel). Kinetic parameters of tumor tissue and normal tissue were compared using the Student t test. Patients were classified as clinical responders or nonresponders according to clinical outcome, and these groups were compared with the pharmacokinetic parameters derived from DCE-MRI. RESULTS: Normal and tumor tissue could be distinguished by the pharmacokinetic parameters Amp and kel (p = 0.001). Clinical responders had a median kep value within the tumor of 2.6 min, while nonresponders showed a higher value (3.6 min), which coincided with longer survival (780 days vs 460 days). CONCLUSIONS: DCE-MRI can be used in patients with MPM to assess tumor microvascular properties and to demonstrate tumor heterogeneity for therapy monitoring. High pretherapeutic values of kep within the tumor correlated with a poor overall response to therapy. 相似文献
109.
David Rollinson Stefanie Knopp Sarah Levitz J. Russell Stothard Louis-Albert Tchuem Tchuenté Amadou Garba Khalfan A. Mohammed Nadine Schur Bobbie Person Daniel G. Colley Jürg Utzinger 《Acta tropica》2013
It is time to raise global awareness to the possibility of schistosomiasis elimination and to support endemic countries in their quest to determine the most appropriate approaches to eliminate this persistent and debilitating disease. The main interventions for schistosomiasis control are reviewed, including preventive chemotherapy using praziquantel, snail control, sanitation, safe water supplies, and behaviour change strategies supported by information, education and communication (IEC) materials. Differences in the biology and transmission of the three main Schistosoma species (i.e. Schistosoma haematobium, S. mansoni and S. japonicum), which impact on control interventions, are considered. Sensitive diagnostic procedures to ensure adequate surveillance in areas attaining low endemicity are required. The importance of capacity building is highlighted. To achieve elimination, an intersectoral approach is necessary, with advocacy and action from local communities and the health community to foster cooperative ventures with engineers, the private sector, governments and non-governmental organizations specialized in water supply and sanitation. Examples of successful schistosomiasis control programmes are reviewed to highlight what has been learnt in terms of strategy for control and elimination. These include St. Lucia and other Caribbean islands, Brazil and Venezuela for S. mansoni; Saudi Arabia and Egypt for both S. mansoni and S. haematobium; Morocco, Tunisia, Algeria, Mauritius and the Islamic Republic of Iran for S. haematobium; Japan and the People's Republic of China for S. japonicum. Additional targets for elimination or even eradication could be the two minor human schistosome species S. guineenisis and S. intercalatum, which have a restricted distribution in West and Central Africa. The examples show that elimination of schistosomiasis is an achievable and desirable goal requiring full integration of preventive chemotherapy with the tools of transmission control. An agenda for the elimination of schistosomiasis would aim to identify the gaps in knowledge, and define the tools, strategies and guidelines that will help national control programmes move towards elimination, including an internationally accepted mechanism that allows verification/confirmation of elimination. 相似文献
110.
Intracranial mass lesions: dynamic contrast-enhanced susceptibility-weighted echo-planar perfusion MR imaging 总被引:50,自引:0,他引:50
Dynamic contrast agent-enhanced perfusion magnetic resonance (MR) imaging provides physiologic information that complements the anatomic information available with conventional MR imaging. Analysis of dynamic data from perfusion MR imaging, based on tracer kinetic theory, yields quantitative estimates of cerebral blood volume that reflect the underlying microvasculature and angiogenesis. Perfusion MR imaging is a fast and robust imaging technique that is increasingly used as a research tool to help evaluate and understand intracranial disease processes and as a clinical tool to help diagnose, manage, and understand intracranial mass lesions. With the increasing number of applications of perfusion MR imaging, it is important to understand the principles underlying the technique. In this review, the essential underlying physics and methods of dynamic contrast-enhanced susceptibility-weighted echo-planar perfusion MR imaging are described. The clinical applications of cerebral blood volume maps obtained with perfusion MR imaging in the differential diagnosis of intracranial mass lesions, as well as the pitfalls and limitations of the technique, are discussed. Emphasis is on the clinical role of perfusion MR imaging in providing insight into the underlying pathophysiology of cerebral microcirculation. 相似文献