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41.
Summary The pharmacokinetics of vindesine were investigated during treatment of 15 patients with progressive malignancies refractory to conventional treatment. Patients were administered one of three IV dose schedules: 3.0 mg/m2 bolus injection, 1.2 mg/m2/day infusion for 5 days, or 2.0 mg/m2/day infusion for 2 days. Concentrations of the drug in the serum and urine were determined by radioimmunoassay. Serum concentrations were highest (5×10-7 M) in patients receiving a bolus injection, but fell to nondetectable levels by 48 h in four of five patients (terminal t1/2 15.0±9.4 h). Compared with bolus injection, 1.2-to 1.4-fold greater areas under the blood concentration curve were observed during infusions of 2.0 mg/m2 and 1.2 mg/m2. Whereas steady-state concentrations (1×10-8 M) were maintained throughout the infusion of 1.2 mg/m2/day progressively increasing serum levels were observed during the infusion of 2.0 mg/m2/day. Serum concentrations fell rapidly following discontinuation of the 2.0-mg/m2 infusion, but were somewhat more sustained in the 1.2-mg/m2 infusion group. The average urinary excretion was similar for each dose-schedule (8%–11% of the total dose). The pharmacokinetics of vindesine are influenced by variations in dose schedule.  相似文献   
42.
Jan Hendrik Louw (1915–1992), considered the father of pediatric surgery in South Africa, gained prominence for his work on congenital intestinal atresia, a condition that had a mortality as high as 75 percent. His hypothesis, that jejunoileal atresia arose from mesenteric circulatory accidents in utero, was the dominant view until recent research uncovered the involvement of genetic and embryological mechanisms. In the mid-1950s he was one of a number of surgeons to resect the enlarged bulbous segment proximal to the site of the atresia, a crucial step in the surgical approach to intestinal atresia that brought mortality below 10 percent. A world leader in surgery as chair of surgery at the Groote Schur Hospital in Cape Town for more than a quarter century, his work in surgical research took root from his private tragedy early in his career of the death of his own infant son of intestinal atresia, a condition to which he would contribute so much.  相似文献   
43.
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (= .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.  相似文献   
44.
目的 分析放射工作者外周血象、淋巴细胞微核及染色体畸变情况,为放射工作者职业防护和健康监测提供依据。方法 对2015年、2017年和2019年连续3次接受健康检查的127名放射工作者进行淋巴细胞微核、染色体及血象分析,将其设为放射组。另外选取133名无射线接触史的医务人员设为对照组;结果 放射组中淋巴细胞微核率和染色体畸变率高于对照组,白细胞和血小板计数低于对照组,均具有统计学意义(P < 0.05)。127名放射工作者外周血白细胞总数随着接触电离辐射时间的增长逐渐降低,染色体畸变率逐渐增加,均具有统计学意义(P < 0.05)。损害工龄大于20年的放射工作者染色体畸变率高于低工龄组,不同损害工龄之间比较无统计学意义(P > 0.05)。核医学与介入治疗工种染色体畸变率高于其他工种,具有统计学意义(P < 0.05)。结论 长时间接触低剂量电离辐射可使放射工作者白细胞总数降低和淋巴细胞染色体畸变率增加,应加强放射工作者防护措施以备降低电离辐射损伤程度,特别要加强核医学和介入治疗放射工作人员的职业防护。  相似文献   
45.
Analysis of 5000 consecutive flexible fiberoptic sigmoidoscopies form the basis of this report. It is concluded that this method of examination of the distal large bowel is not only safe and comfortable for the patient but is a more appropriate examination than the rigid proctosigmoidoscopy because of the significant increase in pathologic material found. This examination has proven practical and acceptable in a multispecialty clinic setting and has completely replaced rigid proctosigmoidoscopy. Flexible sigmoidoscopy is now the standard "routine" examination of the rectum and distal colon. The rationale for this conclusion is presented in this timely report.  相似文献   
46.
The TRAM flap has become the gold standard in breast reconstruction but suffers from the disadvantages of poor color match, different texture, and impaired sensation compared to the normal breast. This study reports on a two-stage procedure to address these problems. The first stage consists of insertion of a tissue expander and surgical delay of the TRAM flap. The second stage consists of removal of the tissue expander and transposition of a deepithelized TRAM flap into the tissue expanded cavity. (The capsule is excised.) Four cases of breast reconstruction are reported. The advantage of this procedure is that it offers the benefits of tissue expansion, viz., normal color match, texture, and sensation, and in addition, reconstruction is achieved with autologous tissue by a pedicled TRAM flap. The vascularity of the TRAM is enhanced by a surgical delay procedure.  相似文献   
47.
Claims regarding amnesia for childhood sexual abuse have often been based on studies of adults' responses to questions of the form, “Was there ever a period of time when you remembered less of the abuse than you do now?” In this experiment, 43 adult (mean age = 42) participants rated their current and prior memories of several nontraumatic childhood/adolescent events. Reports of prior periods of less memory were fairly common. Participants then engaged in “reminiscence” or “enhanced” retrieval activities directed toward remembering more about a selected target event. Following retrieval, 35% of the reminiscence condition participants reported prior poor memory for the target event, as did 70% of the enhanced condition. These results highlight the need for appropriate control conditions in retrospective studies of amnesia for childhood trauma.  相似文献   
48.
PURPOSE: In 1990, fluorouracil (FU) plus levamisole for 1 year became standard adjuvant treatment for patients with high-risk stages II and III colon cancer. Intergroup (INT) 0089 assessed the relative contributions of leucovorin and levamisole in such patients. PATIENTS AND METHODS: From 1988 to 1992, 3,794 patients were randomly assigned. Experimental treatment consisted of one of three chemotherapy regimens: the low-dose leucovorin plus FU (Mayo Clinic; LDLV) regimen, the high-dose leucovorin plus FU (Roswell Park; HDLV) regimen, and the low-dose leucovorin plus levamisole plus FU (LDLV plus LEV) regimen, each administered for 30 to 32 weeks. The control arm was levamisole plus FU (LEV) for 1 year. RESULTS: After a median follow-up of 10 years, of 3,561 eligible patients, 1,691 (47%) have died and 1,330 (37%) have experienced disease recurrence; 137 (10%) of those experiencing recurrence are still alive. A total of 481 patients (13%) died without evidence of recurrence, and 1,723 (48%) are alive and disease free. Although there were toxicity differences among the four arms, none was statistically superior in disease-free or overall survival. CONCLUSION: The 6- to 8-month regimens of LDLV and HDLV without levamisole used in this trial, rather than the previous standard regimen of 12 months of LEV, have become widely used. INT-0089 has long-term follow-up of the largest clinical trial of patients with high-risk colon cancer, documenting not only the durability of the treatment effects, but also the natural history of patients with high-risk colon cancer, and analyses of treatment based on age, race, and comorbid conditions such as obesity, diabetes, and second primary cancers.  相似文献   
49.
Endometriosis, an estrogen-dependent chronic gynecological disease in women of reproductive age, is characterized by a systemic inflammation status involving also red blood cells (RBCs). In this study, we evaluated how the protein oxidative status could be involved in the worsening of RBC conditions due to dapsone intake in endometriotic women in potential treatment for skin or infection diseases. Blood samples from two groups of volunteers, control group (CG) and endometriosis patient group (PG), were analyzed for their content of band 3 tyrosine phosphorylation (Tyr-P) and high molecular weight aggregate (HMWA) in membranes, and glutathione (GSH) content and carbonic anhydrase (CA) activity in cytosol. In endometriotic patients, RBC showed the highest level of oxidative-related alterations both in membrane and cytosol. More interestingly, the addition of dapsone hydroxylamine (DDS-NHOH) could induce further increase of both membranes and cytosol markers, with an enhancement of CA activity reaching about 66% of the total cell enzyme amount. In conclusion, in PG the systemic inflammatory status leads to the inability of counteracting adjunctive oxidative stress, with a potential involvement of CA-related pathologies, such as glaucoma. Hence, the importance of the evaluation of therapeutic approaches worsening oxidative imbalance present in PG RBC is underlined.  相似文献   
50.
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