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51.
Inhibition of tissue factor/factor VIIa activity in plasma requires factor X and an additional plasma component 总被引:10,自引:0,他引:10
A study was carried out to explore requirements for the inhibition of tissue factor-factor VIIa enzymatic activity in plasma. Reaction mixtures contained plasma, 3H-factor IX or 3H-factor X, tissue factor (vol/vol 2.4% to 24%), and calcium. Tissue factor-factor VIIa activity was evaluated from progress curves of activation of factor IX or factor X, plotted from tritiated activation peptide release data. With normal plasma, progress curves exhibited initial limited activation followed by a plateau indicative of loss of tissue factor-factor VIIa activity. With hereditary factor X-deficient plasma treated with factor X antibodies, progress curves revealed full factor IX activation. Adding only 0.4 micrograms/mL factor X (final concentration) could restore inhibition. Inhibition was not observed in purified systems containing 6% to 24% tissue factor, factor VII, 0.5 micrograms/mL, factor IX, 13 micrograms/mL, and factor X up to 0.8 micrograms/mL, but could be induced by adding barium-absorbed plasma to the reaction mixture. Thus, both factor X and an additional material in plasma were required for inhibition. The amount of factor X needed appeared related to the concentration of tissue factor; adding more tissue factor at the plateau of a progress curve induced further activation. These results also indicate that inhibited reaction mixtures contained active free factor VII(a). Preliminary data suggest that inhibition may stem from loss of activity of the tissue factor component of the tissue factor- factor VII(a) complex. 相似文献
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Epidemiological studies designed to detect lung cancer risk and other health effects in communities surrounding arsenic-producing copper smelters were reviewed. The studies were about evenly divided in finding deleterious and 'beneficial' effects of arsenic. All of the studies had insufficient statistical power to detect the small increases in risk that may occur. Even the most powerful studies were not designed to detect relative risks less than about 1.2 and the majority of the studies had little power to detect risks under 2.0. Confidence intervals for the relative risks from these studies were not very useful in putting an upper bound on adverse effects of arsenic. Sources of bias and other difficulties with community health studies are also discussed. We argue that these studies may be a good and economical first investigation but, due to a lack of power, null findings do not rule out the possibility of excess risks that may be significant from a public health viewpoint. 相似文献
54.
The relationship between type of biopsy-mastectomy procedure and four sets of independent variables (physician, patient, hospital and tumor characteristics) was examined for 993 locally-staged breast cancer patients diagnosed between 1974 and 1981 in 13 counties of western Washington State. Time trends were also investigated. Cases were selected from records of a population-based cancer registry. The frequency of the two-step procedure, in which biopsy and surgery occur on different days, increased from 28 to 57% during the 8-year study period. Use of the two-step procedure was associated with younger age of the patient, less suspicious symptoms or mammogram results, younger physician cohorts and hospitals with government and health maintenance organization proprietorship. These relationships remained unchanged after controlling for potentially confounding variables. There were also substantial differences between individual hospitals in the frequency of the two-step procedure, suggesting differing schools of thought in different locales. 相似文献
55.
Biologic prosthesis reduces recurrence after laparoscopic paraesophageal hernia repair: a multicenter, prospective, randomized trial 总被引:18,自引:0,他引:18 下载免费PDF全文
Oelschlager BK Pellegrini CA Hunter J Soper N Brunt M Sheppard B Jobe B Polissar N Mitsumori L Nelson J Swanstrom L 《Annals of surgery》2006,244(4):481-490
OBJECTIVE: Laparoscopic paraesophageal hernia repair (LPEHR) is associated with a high recurrence rate. Repair with synthetic mesh lowers recurrence but can cause dysphagia and visceral erosions. This trial was designed to study the value of a biologic prosthesis, small intestinal submucosa (SIS), in LPEHR. METHODS: Patients undergoing LPEHR (n = 108) at 4 institutions were randomized to primary repair -1 degrees (n = 57) or primary repair buttressed with SIS (n = 51) using a standardized technique. The primary outcome measure was evidence of recurrent hernia (> or =2 cm) on UGI, read by a study radiologist blinded to the randomization status, 6 months after operation. RESULTS: At 6 months, 99 (93%) patients completed clinical symptomatic follow-up and 95 (90%) patients had an UGI. The groups had similar clinical presentations (symptom profile, quality of life, type and size of hernia, esophageal length, and BMI). Operative times (SIS 202 minutes vs. 1 degrees 183 minutes, P = 0.15) and perioperative complications did not differ. There were no operations for recurrent hernia nor mesh-related complications. At 6 months, 4 patients (9%) developed a recurrent hernia >2 cm in the SIS group and 12 patients (24%) in the 1 degrees group (P = 0.04). Both groups experienced a significant reduction in all measured symptoms (heartburn, regurgitation, dysphagia, chest pain, early satiety, and postprandial pain) and improved QOL (SF-36) after operation. There was no difference between groups in either pre or postoperative symptom severity. Patients with a recurrent hernia had more chest pain (2.7 vs. 1.0, P = 0.03) and early satiety (2.8 vs. 1.3, P = 0.02) and worse physical functioning (63 vs. 72, P = 0.03 per SF-36). CONCLUSIONS: Adding a biologic prosthesis during LPEHR reduces the likelihood of recurrence at 6 months, without mesh-related complications or side effects. 相似文献
56.
Large-cell lymphoma of the spleen: CT appearance 总被引:2,自引:0,他引:2
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沙赛普肽注射液的细菌内毒素检测 总被引:2,自引:0,他引:2
目的:用鲎试剂检测沙赛普肽注射液中的细菌内毒素。方法:采用鲎试法(LT)与家兔法(RT)对沙赛普肽注射液进行细菌内毒素检测。结果:两种方法检查结果一致,用直接稀释法排除细菌内毒素的干扰。结论:以鲎试法用于控制沙赛普注射液的热原方法可行。 相似文献
60.
The dental implications of bisphosphonates and bone disease 总被引:3,自引:0,他引:3