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761.
前胡伪品碎叶山芹的生药学研究   总被引:1,自引:1,他引:1  
目的:对浙产前胡伪品碎叶山芹进行产地调查和鉴别。方法:采用生药学研究和理化分析法。结果:前胡及其伪品碎叶山芹的原植物形态、性状、显微特征及理化性质均有差异,可资鉴别真伪。结论:碎叶山芹不可作前胡药用。  相似文献   
762.
Hairy cell leukemia: a tumor of pre-plasma cells   总被引:7,自引:0,他引:7  
Monoclonal antibodies defining B-, T-, and myeloid-restricted cell surface antigens were used to characterize the lineage and state of differentiation of tumor cells isolated from 22 patients with hairy cell leukemia (HCL). These tumors were shown to be of B lineage because they strongly expressed the B cell-restricted antigens B1 and B4 and lacked T cell- and monocyte-restricted antigens. Moreover, the strong expression of the plasma cell-associated PCA-1 antigen on the majority of hairy cells suggested that these tumors correspond to later stages of B cell ontogeny. Dual fluorescence experiments further confirmed that HCL splenocytes that coexpressed B1 and PCA-1 demonstrated both the morphology and tartrate-resistant acid phosphatase positivity of hairy cells. The observation that some hairy cells either spontaneously produce immunoglobulin (Ig) or could be induced to proliferate and secrete Ig provides complementary support for the view that HCL is a pre-plasma cell tumor. However, staining of hairy cells with anti-IL2R1 monoclonal antibody, which is directed to the T cell growth factor receptor and/or with the anti-Mo1 reagent, directed to C3bi complement receptor, distinguish these cells from currently identified B cells.  相似文献   
763.
乳腺癌Crose改良根治术114例   总被引:1,自引:1,他引:0  
袁时芳  王岭  宁莫凡  张中汉  杨华 《医学争鸣》2001,22(7):F003-F003
0 引言 乳腺癌是严重危害女性身体健康的恶性肿瘤之一 ,改良根治术已成为目前主要的治疗手段 . 1985 / 1998年 ,我院行 Crose改良根治术治疗乳腺癌 114例 ,根治疗效好 ,并发症少 ,现报告如下 .1 对象和方法1.1 对象  114例患者 ,均为女性 .年龄 2 3~ 6 7岁 ,平均46 .5岁 ,病程 3d~ 10 a,小于 6 m o6 8例 ,6~ 12 mo37例 ,大于 12 mo9例 ,癌肿部位 :位于外象限 76例 ,中央部 2 8例 ,内象限 10例 ,原发肿瘤直径 1~ 8cm,其中 <3cm,42例 ,>3cm,72例 ,腋淋巴结转移 48例 ,转移淋巴结数目 1~ 4枚不等 ,直径均 <2 cm,无转移 76例 .辅助检…  相似文献   
764.
We evaluated medical in comparison to surgical plus medical (surgical) treatment of unstable angina using a prospective randomized protocol that stratified patients by clinical presentation and by invasive evaluation of left ventricular (LV) function. Clinical presentations were as follows--type 1: progressive or new onset angina relieved by medication; type 2: prolonged bouts of angina poorly or incompletely relieved by medication. Abnormal LV function was arbitrarily defined as ejection fraction less than 0.50 or LV end-diastolic pressure 16 mm Hg or more. Of 468 patients, 237 were assigned to medical and 231 to surgical therapy. There were 374 type 1 and 94 type 2 patients. LV function was normal in 334 and abnormal in 134 patients. Compared with results at 24 months, this 60-month follow-up study showed important differences in survival for patients with three-vessel disease: 75% for medical and 89% for surgical patients (p less than 0.02). The cumulative 5-year rate of repeat hospitalizations for cardiac reasons was less with surgical patients for either clinical presentation. For type 1, medical patients had a 56% rate, and surgical patients had a 42% rate (p = 0.004). For type 2, medical patients had a 62% rate, and surgical patients had a 43% rate (p = 0.05). Overall mortality did not differ between the two treatments, and this remained true in type 1 versus type 2 patients and in those with normal versus abnormal LV function. However, regression analysis of medical and surgical groups with ejection fraction as a continuous variable showed that mortality of medical patients depended on ejection fraction (p = 0.004), whereas the mortality of surgical patients did not (p = 0.76), and survival in the surgical group was higher in the lowest ejection fraction tercile-73% for medical and 86% for surgical patients, p = 0.03. We conclude that surgery improves survival in patients with three-vessel disease and leads to fewer subsequent hospitalizations for cardiac reasons. An impaired ejection fraction had an adverse impact on survival of medical patients but not on surgical patients, and mortality in surgical patients was improved compared with medical patients in the lowest ejection fraction tercile.  相似文献   
765.
Patients undergoing hypothermic cardiopulmonary bypass are often receiving aspirin therapy. Hypothermia, aspirin and cardiopulmonary bypass can each induce a platelet function defect, but it is not known if the effects of aspirin and hypothermia are additive in this regard. To address this question in humans in vivo, the forearm skin temperature of healthy volunteers was equilibrated and maintained at either normothermia (32 degrees C) or hypothermia (28 degrees C or 22 degrees C) before and 16 h after the ingestion of 650 mg aspirin. A standardized template bleeding time was performed on the forearm and the shed blood emerging from the wound was assayed for platelet surface P-selectin expression by whole blood flow cytometry (reflecting alpha granule secretion) and thromboxane B2 (the stable metabolite of thromboxane A2) by radioimmunoassay. Hypothermia resulted in marked prolongation of the bleeding time. Aspirin resulted in prolongation of the bleeding time under normothermic conditions, but only minimally augmented the hypothermia-induced prolongation of the bleeding time. Platelet surface P-selectin up-regulation in shed blood was abolished by hypothermia. Aspirin had no effect on maximal platelet surface P-selectin expression under normothermic or hypothermic conditions. Both hypothermia and aspirin resulted in markedly reduced shed blood thromboxane B2. Although aspirin slightly augmented the hypothermia-induced reduction in shed blood thromboxane B2, the concentration of thromboxane generated in shed blood under hypothermic conditions in the absence of aspirin had no effect on platelet surface P-selectin or platelet aggregation in whole blood. In conclusion, as determined by three independent parameters of the shed blood emerging from a standardized bleeding time wound (bleeding time, platelet surface P-selectin, and thromboxane B2), aspirin did not significantly augment hypothermia-induced platelet dysfunction in vivo.  相似文献   
766.
To investigate the efficacy of nadolol in the prevention of supraventricular arrhythmias after coronary artery bypass graft (CABG) surgery, 148 patients undergoing elective CABG were randomized in double-blind, placebo-controlled fashion to receive either nadolol or placebo. The test medication was started on the first postoperative morning and maintained as a single daily dose for 6 weeks. Aside from routine daily clinical evaluation and postoperative electrocardiographic monitoring, patients underwent 24-hour Holter recording once preoperatively and 3 times postoperatively. Seven patients were excluded from the evaluation of efficacy analysis because of insufficient postoperative data. There were no significant differences between the patients receiving nadolol (n = 67) and those receiving placebo (n = 74) with respect to age, preoperative heart rate, previous medications (including beta blockers), incidence of previous myocardial infarction, frequency of preoperative ventricular and supraventricular arrhythmias, concomitant valvular heart disease, mean cardiopulmonary bypass time, mean aortic cross-clamp time, use of blood and crystalloid cardioplegia, mean number of bypass grafts placed, postoperative use of inotropic agents and catecholamines and incidence of perioperative myocardial infarction. Analysis of postoperative Holter recordings showed that the heart rate was consistently and significantly higher in the placebo group throughout the period of the study (p less than 0.001). The average number of premature atrial contractions was significantly smaller in the nadolol group (p less than 0.05), and nadolol patients had fewer ventricular premature complexes, couplets and non-sustained ventricular tachycardias during the first week postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
767.
Risk factors for morbidity and mortality after colectomy for colon cancer   总被引:22,自引:2,他引:22  
PURPOSE: Comorbid conditions affect the risk of adverse outcomes after surgery, but the magnitude of risk has not previously been quantified using multivariate statistical methods and prospectively collected data. Identifying factors that predict results of surgical procedures would be valuable in assessing the quality of surgical care. This study was performed to define risk factors that predict adverse events after colectomy for cancer in Department of Veterans Affairs Medical Centers. METHODS: The National Veterans Affairs Surgical Quality Improvement Program contains prospectively collected and extensively validated data on more than 415,000 surgical operations. All patients undergoing colectomy for colon cancer from 1991 to 1995 who were registered in the National Veterans Affairs Surgical Quality Improvement Program database were selected for study. Independent variables examined included 68 preoperative and 12 intraoperative clinical risk factors; dependent variables were 21 specific adverse outcomes. Stepwise logistic regression analysis was used to construct models predicting the 30-day mortality rate and 30-day morbidity rates for each of the ten most frequent complications. RESULTS: A total of 5,853 patients were identified; 4,711 (80 percent) underwent resection and primary anastomosis. One or more complications were observed in 1,639 of 5,853 (28 percent) patients. Prolonged ileus (439/5,853; 7.5 percent), pneumonia (364/5,853; 6.2 percent), failure to wean from the ventilator (334/5,853; 5.7 percent), and urinary tract infection (292/5,853; 5 percent) were the most frequent complications. The 30-day mortality rate was 5.7 percent (335/5,853). For most complications, 30-day in-hospital mortality rates were significantly higher for patients with a complication than for those without. Thirty-day mortality rates exceeded 50 percent if postoperative coma, cardiac arrest, a pre-existing vascular graft prosthesis that failed after colectomy, renal failure, pulmonary embolism, or progressive renal insufficiency occurred. Preoperative factors that predicted a high risk of 30-day mortality included ascites, serum sodium >145 mg/dl, do not resuscitate status before surgery, American Society of Anesthesiologists classes III and IV OR V, and low serum albumin. CONCLUSIONS: Mortality rates after colectomy in Veterans Affairs hospitals are comparable with those reported in other large studies. Ascites, hypernatremia, do not resuscitate status before surgery, and American Society of Anesthesiologists classes III and IV OR V were strongly predictive of perioperative death. Clinical trials to decrease the complication rate after colectomy for colon cancer should focus on these risk factors.Supported by the Veterans Health Administration of the U.S. Department of Veterans Affairs, Washington, D.C.Dr. Daley is a Senior Research Associate in the Career Development Program of Health Services Research and Development Service in the Department of Veterans Affairs.  相似文献   
768.
Biotinylated interleukin-4 (IL-4) was used to examine IL-4 receptor (IL- 4R) expression on a range of human B-cell lines by flow cytometry. Using high concentrations of biotinylated IL-4, we have identified a novel low-affinity IL-4 receptor expressed at high levels on pre-B lines. Expression of this low-affinity receptor did not correlate with detected mRNA levels for the previously cloned receptor or with reactivity of two anti-human IL-4R monoclonal antibodies (MoAb). Radiolabeled IL-4 cross-linking studies using pre-B lines showed a doublet of 65 to 75 Kd in contrast to the 110- to 130-Kd molecule detected on cells expressing the cloned IL-4R. A soluble IL-4 binding protein (IL-4bp) was purified from the supernatants of three pre-B lines expressing the low-affinity receptor on their surface. IL-4bp could block both IL-4-mediated CD23 induction on tonsil B cells and IL- 4-induced inhibition of proliferation of the pre-B line JM1. Partial N- terminal amino acid sequence was obtained from purified IL-4bp that confirmed this protein to be novel. A 12 amino acid peptide based on the IL-4bp sequence was used to produce a polyclonal antiserum that was reactive with purified IL-4bp, and also bound to the surface of pre-B cells but not to murine CTLL cells transfected with the human IL-4R. Blocking MoAb against the previously characterized high-affinity receptor inhibited IL-4-mediated proliferation of hIL-4R+ CTLL cells but had no effect on IL-4-induced inhibition of JM1 cell proliferation, and only partially inhibited IL-4-mediated CD23 and sIgM induction and proliferation of tonsil B cells. The data presented here provide evidence for a novel cell-surface expressed low-affinity IL-4R that also exists as a biologically active soluble IL-4 binding protein.  相似文献   
769.
Friedberg  RC; Donnelly  SF; Boyd  JC; Gray  LS; Mintz  PD 《Blood》1993,81(12):3428-3434
Numerous independent and interdependent factors are involved in the posttransfusion platelet response. Factors such as ABO match and platelet age are related to circumstances potentially under the control of the blood bank physician and therefore may permit circumvention by an active transfusion service. On the other hand, factors such as fever or sepsis may be unavoidable, being related more to the individual patient or clinical condition. To evaluate which factors could be circumvented, we prospectively followed the 1-hour corrected count increments (CCIs) for 962 single-donor apheresis platelet transfusions to 71 refractory hematologic oncology inpatients, with concomitant recording of implicated factors. Stepwise regression analysis allowed for determination of which concurrent and confounding clinical-, patient-, and blood bank-related factors significantly affected the CCIs. Although many implicated factors proved to be independently associated with an increased or decreased CCI, we found that no single variable consistently explained the CCI variation across the patient population. Each patient appeared sensitive to one or a few particular factors, but because of marked intraindividual variation, it was not possible to identify a priori which factors were important for a given patient. The single exception was a solid-phase red blood cell adherence assay used to cross-match platelets, but only for alloimmunized patients. We also evaluated the utility of requesting HLA- matched platelets from the local suppliers and maintained a clear distinction between platelets simply ordered as HLA matched and actually HLA-identical platelets. Accounting for the confounding clinical-, patient-, and blood bank-related factors, the cross-match assay was a better predictor of an adequate CCI than ordering platelets as HLA matched.  相似文献   
770.
Tumor necrosis factor-alpha (TNF-alpha) can bind to two distinct transmembrane receptors, the p55 and p75 TNF receptors. We compared the capability of two mutant TNF proteins with exclusive affinity for the p55 or p75 TNF receptor with that of wild type TNF, to activate the hemostatic mechanism in baboons. Both activation of the coagulation system, monitored by the plasma levels of thrombin-antithrombin III complexes, and activation of the fibrinolytic system (plasma levels of tissue-type plasminogen activator, and plasminogen activator inhibitor type I), were of similar magnitude after intravenous injection of wild type TNF or the TNF mutant with affinity only for the p55 receptor. Likewise, wild type TNF and the TNF p55 specific mutant were equally potent in inducing neutrophil degranulation (plasma levels of elastase- alpha 1-antitrypsin complexes). Wild type TNF tended to be a more potent inducer of secretory phospholipase A2 release than the p55 specific TNF mutant. Administration of the TNF mutant binding only to the p75 receptor did not induce any of these responses. We conclude that TNF-Induced stimulation of coagulation, fibrinolysis, neutrophil degranulation, and release of secretory phospholipase A2 are predominantly mediated by the p55 TNF receptor.  相似文献   
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