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排序方式: 共有1547条查询结果,搜索用时 14 毫秒
1.
Tiberiu Ezri Islam Zahalka Deeb Zabeeda Zeev Feldbrin Alexander Eidelman Reuven Zimlichman Benjamin Medalion Shmuel Evron 《Journal canadien d'anesthésie》2006,53(2):139-145
BACKGROUND: We hypothesized that the incidence of hypotension during total knee replacement (TKR) surgery is lower in patients given combined spinal-epidural (CSE) anesthesia vs those receiving epidural anesthesia alone. METHODS: In a prospective study, 80 American Society of Anesthesiologists I-II patients (aged 40-80 yr), undergoing elective TKR surgery were randomly assigned to either CSE anesthesia (CSE, n = 40) or epidural anesthesia alone (Epidural, n = 40). Hemodynamic measurements included oscillometric mean arterial blood pressure (MAP), heart rate (HR), and cardiac index (CI) as determined by thoracic bioimpedance; systemic vascular resistance (SVR) was calculated. Our primary endpoint (outcome) was the number of hypotension episodes (defined as MAP < 70 mmHg). RESULTS: Using univariate analysis, we found no differences between the groups in regards to MAP, HR, CI, or SVR during the perioperative period. The incidence of hypotension was similar in both groups (two patients in each group), as was the incidence of bradycardia (12 patients in CSE, 7 in Epidural; P = 0.2). There were no differences between groups in other hemodynamic measurements including CI and calculated SVR. Analgesia supplementation with fentanyl was more frequently required in the Epidural group (20 vs 6 patients - P = 0.03). CONCLUSION: Combined spinal-epidural anesthesia and epidural anesthesia alone during TKR surgery are associated with the same incidence of hypotension with statistically and clinically similar hemodynamic responses. 相似文献
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Ofer Gemer Benjamin Piura Shmuel Segal Ilana Yanai Inbar 《International journal of gynecological pathology》2003,22(4):398-400
Chondroid syringoma of the vulva is an extremely rare tumor. Of the previously reported cases, only one was clinically malignant. The authors describe a case of chondroid syringoma of the right labium majus from which arose a papillary adenocarcinoma. A right inguinal lymph node was replaced with metastatic adenocarcinoma. 相似文献
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Victoria L. Herzberg 《Immunological investigations》1991,20(5):507-513
Serum, which is required for activation of T cells in vitro, was fractionated to isolate and identify major supportive components. The serum activity concentrated exclusively with the lipoprotein fractions LDL and HDL. Furthermore, oleic and linoleic acids were equally active supplements, suggesting that resting T cells may require exogenous lipid because they are incapable of synthesizing fatty acid. A survey of fatty acids disclosed that all were capable of some degree of support. Titration delineated the narrow concentration range of lipid supplements successful in supporting T cell proliferation and demonstrated that concentrations must be rigidly controlled to optimize cell proliferation. 相似文献
5.
The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis.
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M C Herzberg G D MacFarlane K Gong N N Armstrong A R Witt P R Erickson M W Meyer 《Infection and immunity》1992,60(11):4809-4818
A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor. 相似文献
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We report a case of an 18-month-old male, born to a woman with third trimester febrile illness, who had a history of congestive heart failure and respiratory distress, cardiomegaly, and electrocardiographic (ECG) findings suggestive of cardiomyopathy and myocarditis. After gradual improvement in heart size and function with pharmacologic therapy, he developed a terminal episode of respiratory distress and cardiogenic shock, with ECG findings of an anterolateral infarct. At autopsy it was found that endocardial fibroelastosis with mural thrombi in the left ventricle had been complicated by thromboembolism to the left anterior descending coronary artery, resulting in transmural infarction of the anteroseptal region of the left ventricle. Myocardial infarction is a potential but unusual thromboembolic complication of endocardial fibroelastosis. A high index of suspicion for coronary artery thromboemboli should be maintained in pediatric patients with cardiomyopathy and suspected myocardial infarction. 相似文献
8.
Michael Schirner Frank Herzberg Roland Schmidt Michael Streit Michael Schoning Michael Hummel Christine Kaufmann Eckhard Thiel Ernst-Dieter Kreuser 《Clinical & experimental metastasis》1997,16(5):427-435
The integrin 51 seems to be the most relevant receptor of tumor cells for binding to fibronectin. Although numerous studies suggest a role of tumor cell fibronectin interaction in tumor metastasis, differential integrin expression on tumor cells has, however, not been correlated with metastatic capabilities. We addressed this question by transfection of the integrin 51 cDNA into HT-29 human colon carcinoma cells which led to de novo expression of functional integrin 51. Similar to other reports, expression of the integrin 51 in HT-29 tumor cells exerted an inhibitory action on cell proliferation as indicated in our study by formation of fewer colonies in soft agar. The tumor growth inhibitory property of the integrin 51 was also shown by reduction of subcutaneous xenograft growth in nude mice to approximately 50% of that of control transfectants. For the first time, we found that several clones of integrin 5 subunit transfectants displayed dramatically reduced formation of lung colonies and cutaneous metastasis after intravenous injec-tion into nude mice. While most animals inoculated with control transfectant cells formed macroscopically visible lung colonies ranging from 12.6 ± 2.6 to 22.0 ± 6.6 (mean colony number ± SEM), mice inoculated with HT-29 cell clones expressing the integrin a5b1 were almost completely free of lung colonies (ranging from 0.0 ± 0 to 0.2 ± 0.1). Our results imply that integrin 51 expression inhibits circulating tumor cells in pursuing late steps of the metastatic process as represented by the artificial metastasis (lung colonisation) model. © Rapid Science Ltd. 相似文献
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Wolff N Yannai S Karin N Levy Y Reifen R Dalal I Cogan U 《The Journal of allergy and clinical immunology》2004,114(5):1151-1158
BACKGROUND: The increased consumption of foods containing sesame seeds is paralleled by an increase in reported sesame-induced allergic reactions. OBJECTIVE: This study aimed at identifying and characterizing the linear B-cell epitopes of the 14-kd beta-globulin, the major allergen of sesame seed. METHODS: A peptide containing 71 amino acids (peptide B) was previously identified by us as the IgE-binding region on beta-globulin. To determine the amino acid sequence of the IgE-binding sites on peptide B, we synthesized overlapping peptides 20 and 10 amino acid residues long that span the entire length of peptide B, which were offset from each other by 10 and 2 amino acid residues, respectively. Sera from 20 subjects given diagnoses of allergy to sesame beta-globulin served to identify the epitopes by using the dot-blot test. RESULTS: At least 9 different IgE-recognition sites were identified on peptide B. Three of them, numbers 2, 3, and 13 (corresponding to amino acids 46-55, 48-57, and 76-86, respectively, in the beta-globulin sequence), appeared to be immunodominant IgE-binding epitopes. Also, these peptides were best recognized in terms of intensity of response. There was no obvious sequence motif shared by the 9 different IgE-binding epitopes of beta-globulin. However, approximately 60% of the amino acids represented in the epitopes are hydrophobic residues. CONCLUSION: Identification of the IgE-binding epitopes might provide a better understanding of the functional role the allergens play in the disease and might have implications for immunodiagnosis and probably immunotherapy. 相似文献