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21.
Cardiac myxomas     
Cardiac myxoma is the most common primary tumor of the heart. Between 1970 and 1998, 33 myxomas from patients operated at the Cardiosurgical Department were submitted for pathological examination. A review of age, sex and clinical symptoms of the patients as well as of gross and histological features of the tumors is presented. Immunohistochemical examination was performed on 10 selected myxomas-reactivity to vimentin, desmin, S-100 protein, cytokeratin and FVIIIR-Ag. The necessity of histological examination of the embolectomy material is stressed.  相似文献   
22.
The immobilization of vesicles has been conceptualized as a method to functionalize biointerfaces. However, the preservation of their integrity post immobilization remains a considerable challenge. Interfacial interactions can cause vesicle rupture upon close surface contact and non-specific protein adsorption impairing surface functions. To date, immobilization of vesicles has relied solely on either entrapment or prior modification of vesicles, both of which require laborious preparation and limit their applications. This work develops a bioinspired strategy to pin vesicles without prior modification while preserving their intact shape. This work introduces antifouling diblock copolymers and ultrathin surface-attached hydrogels containing a brush-like interface consisting of a bottle brush copolymer of N-(2-hydroxypropyl) methacrylamide (HPMA) and N-(3-methacrylamidopropyl)-N,N-dimethyldodecan-1-aminiumiodide (C12+). The presence of positive charges generates an attractive force that pulls vesicles toward the surface. At the surface, the amphiphilic properties of the combs facilitate their insertion into the membrane, mimicking the harpooning mechanism observed in antimicrobial peptides. Importantly, the antifouling poly(HPMA) backdrop serves to safeguard the vesicles by preventing deformation and breakage. Using a combination of thermodynamic analysis, surface plasmon resonance, and confocal laser scanning microscopy, this work demonstrates the efficiency of this biomimetic system to capture vesicles while maintaining an antifouling interface necessary for bioapplications.  相似文献   
23.
Background: Opioids can produce peripheral analgesic effects by activation of opioid receptors on sensory nerves. This study was designed (1) to examine a novel route of opioid administration, the intraperitoneal injection; (2) to compare this to interpleural application, and (3) to compare opioid with local anesthetic effects under both conditions.

Methods: At the end of laparoscopic cholecystectomy, 110 patients received the following injections in a double-blind, randomized manner: Group 1 (n = 18) was given intraperitoneal morphine (1 mg in 20 ml saline) and 20 ml intravenous saline. Group 2 (n = 17) received intraperitoneal saline and 1 mg intravenous morphine. Group 3 (n = 15) received 20 ml 0.25% intraperitoneal bupivacaine and intravenous saline. Group 4 (n = 20) received interpleural morphine (1.5 mg in 30 ml saline) and 30 ml intravenous saline. Group 5 (n = 20) received interpleural saline and 1.5 mg intravenous morphine. Group 6 (n = 20) received 30 ml 0.25% interpleural bupivacaine and intravenous saline. Postoperative pain was assessed using a visual analog scale, a numeric rating scale, and the McGill pain questionnaire. Pain localization, supplemental analgesic consumption, vital signs, and side effects were recorded for 24 h.

Results: Neither intraperitoneal nor interpleural morphine produced significant analgesia after laparoscopic cholecystectomy (P > 0.05, Kruskal-Wallis test), whereas interpleural bupivacaine was effective (P < 0.05, Kruskal-Wallis test, up to 6 h postoperatively) but not intraperitoneal bupivacaine (P > 0.05, Kruskal-Wallis test). Shoulder pain was not prevalent in the majority of patients during the first 6 h. By 24 h, about half of the patients complained of shoulder pain, which was rated "low" by about one-third of all patients. No significant side effects occurred.  相似文献   

24.
To make an informed decision when choosing a contraceptive, women and couples need to know how effective different methods are when used perfectly, where perfect use is defined as following the directions for use. In this article, we show that unbiased estimates of pregnancy rates during perfect use can be guaranteed only if information on consistency and correctness of use is available for each menstrual cycle. The estimated probability of pregnancy during a year of perfect use among the subset of women who always used a method perfectly will be biased upward.  相似文献   
25.
BACKGROUND AND AIMS: The increasing incidence of reoperations in coronary surgery associated with higher perioperative risks is a challenge for refinement of the surgical methods. The aim of the work is to prove the feasibility and satisfactory intermediate results of minimally invasive axillary-coronary artery bypass reconstruction in redo coronary surgery in case the left internal mammary artery had already been harvested. MATERIAL AND METHODS: Three patients (six months, two and six years after primary coronary artery bypass grafting) admitted for redo coronary surgery because of a recurrence of angina and proven malfunction of the left internal mammary artery-left anterior descending coronary artery anastomosis. An axillary-coronary venous graft was performed via left anterior small thoracotomy (LAST) on a beating heart in all three cases. RESULTS: Excellent patency of the graft was noted on control angiography within 9 days after the procedure together with good clinical improvement in midterm follow-up. CONCLUSION: Minimally invasive axillary-coronary artery bypass via LAST access in redo coronary surgery is a good alternative in cases where the left internal mammary artery cannot be used.  相似文献   
26.
Increase of regulatory T cells in the peripheral blood of cancer patients.   总被引:70,自引:0,他引:70  
PURPOSE: T cells constitutively expressing both CD4 and CD25are essential for maintenance of self-tolerance and therefore have been referred to as regulatory T cells (Treg). Experimental tumor models in mice revealed that Tregs are potent inhibitors of an antitumor immune response. The current study was designed to determine whether cancer patients exhibit an expanded Treg pool. EXPERIMENTAL DESIGN: The frequency of Tregs in the peripheral blood of 42 patients suffering from epithelial malignancies and from 34 healthy controls was determined by flow cytometry. The immunoregulatory properties of CD4(+)CD25(+) and CD4(+)CD25(-) T cells were characterized by proliferation and suppression assays. Cocultures with natural killer (NK) cells were performed to determine the impact of Tregs on NK-mediated cytotoxicity. RESULTS: Patients with epithelial malignancies show an increase of CD4(+)CD25(+) T cells in the peripheral blood with characteristics of Tregs, i.e., they are CD45RA(-), CTLA-4(+), and transforming growth factor beta(+). Notably, CD4(+) T cells from cancer patients are characterized by an impaired proliferative capacity, which is restored to the extend of CD25-depleted CD4(+) T cells from control persons by prior removal of CD25(+) T cells. In contrast to CD4(+)CD25(-) T cells, isolated CD4(+)CD25(+) T cells from cancer patients were anergic towards T cell receptor stimulation. In addition, CD4(+)CD25(+) T cells suppressed the proliferation of CD4(+)CD25(-) T cells. When cultured together with CD56(+) NK-cells, CD4(+)CD25(+) T cells from cancer patients effectively inhibited NK-cell-mediated cytotoxicity. CONCLUSIONS: Thus, we provide evidence of an increased pool of CD4(+)CD25(+) regulatory T cells in the peripheral blood of cancer patients with potent immunosuppressive features. These findings should be considered for the design of immunomodulatory therapies such as dendritic cell vaccination.  相似文献   
27.
Pure parahydrogen (pH2) is the prerequisite for optimal pH2‐based hyperpolarization experiments, promising approaches to access the hidden orders of magnitude of MR signals. pH2 production on‐site in medical research centers is vital for the proliferation of these technologies in the life sciences. However, previously suggested designs do not meet our requirements for safety or production performance (flow rate, pressure or enrichment). In this article, we present the safety concept, design and installation of a pH2 converter, operated in a clinical setting. The apparatus produces a continuous flow of four standard liters per minute of ≈98% enriched pH2 at a pressure maximum of 50 bar. The entire production cycle, including cleaning and cooling to 25 K, takes less than 5 h, only ≈45 min of which are required for actual pH2 conversion. A fast and simple quantification procedure is described. The lifetimes of pH2 in a glass vial and aluminum storage cylinder are measured to be T1C(glass vial) = 822 ± 29 min and T1C(Al cylinder) = 129 ± 36 days, thus providing sufficiently long storage intervals and allowing the application of pH2 on demand. A dependence of line width on pH2 enrichment is observed. As examples, 1H hyperpolarization of pyridine and 13C hyperpolarization of hydroxyethylpropionate are presented. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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