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71.
PURPOSE: To demonstrate the feasibility and efficacy of six ambulatory high-dose sequential chemotherapy courses that include three intensified cycles supported by stem-cell infusion in high-risk and high-intermediate-risk untreated non-Hodgkin's lymphoma (NHL) patients. PATIENTS AND METHODS: A pilot nonrandomized study included 20 untreated patients aged less than 60 years with aggressive histologically identified NHL and two or three adverse-prognosis criteria (International Index). Patients received an ambulatory regimen with high-dose chemotherapy supported by granulocyte colony-stimulating factor (G-CSF) and repeated peripheral-blood stem-cell (PBSC) infusion. The median age was 39 years (range, 20 to 59), with 13 men and seven women. Chemotherapy consisted of one cycle every 21 days for a total of six cycles. The first three cycles (A1, A2, and A3) consisted of cyclophosphamide (Cy) 3,000 mg/m2, doxorubicin (Doxo) 75 mg/m2, and vincristine 2 mg (plus corticosteroids). The last three cycles (B4, B5, and B6) consisted of the same drug combination plus etoposide 300 mg/m2 and cisplatin 100 mg/m2. For an expected duration of 18 weeks, the projected dose-intensity was 25 mg/m2/wk for Doxo and 1,000 mg/m2/wk for Cy. G-CSF 300 micrograms was administered from day 6 following each cycle until neutrophil reconstitution. Two aphereses were performed at approximately day 13 after each A cycle, and PBSCs were injected at day 4 of each B cycle. Radiotherapy on tumor masses > or = 5 cm was scheduled after completion of the last cycle. RESULTS: The median duration of grade 4 neutropenia was 1 day (range, 0 to 7) for each A cycle and 4 days (range, 1 to 10) for each B cycle (P = .02). The median duration of grade 4 thrombopenia was 0 days (range, 0 to 8) for each A cycle and 6 days (range, 1 to 21) for each B cycle (P < .001). Hospitalization for febrile neutropenia was required for 18% and 44% of patients during cycles A and B, respectively (P < .01). Only three patients did not complete the protocol: one due to emergency surgery after cycle B4, one who died after cycle B5 from interstitial pneumonia, and one with delayed hematologic reconstitution after cycle B4. Chemotherapy delivery was optimal (median actual relative dose-intensity, 97%; range, 66 to 100). The median total dose administered over 18 weeks was 18,000 mg Cy (range, 12,000 to 18,000), 450 mg Doxo (range, 300 to 450), 900 mg etoposide (range, 300 to 900), and 300 mg cisplatin (range, 100 to 300). Evaluation of response after six courses showed 13 complete remissions ([CRs] 65%), four partial remissions (PRs), two nonresponses (NRs), and one toxic death. With a median follow-up period of 25 months (range, 16 to 43), 15 patients are alive, with 12 in continuous first CR; five patients relapsed (four of four PRs and one of 13 CRs). Two-year survival and failure-free survival (FFS) rates are 73% and 56%, respectively. The disease-free survival (DFS) rate for the CRs is 86%. CONCLUSION: PBSC support contributes to the feasibility of first-line, very-high-dose, ambulatory chemotherapy delivery in poor-risk NHL and is associated with a high rate of remission and FFS.  相似文献   
72.
A study of the pre-operative condition of seventy-five hands afflicted with Dupuytren's contracture is followed by an analysis of the results of limited fasciectomy approached by midlateral digital and transverse palmar excisions. The palmar wounds were left open and healing occurred with minimal complications. The correction of contractures compares favourably with that achieved using other techniques of access and wound closure.  相似文献   
73.
The aglycone, 3-hydroxybenzo[a]pyrene, was metabolized to 3-benzo[a]pyrenyl-beta-D-glucopyranosiduronic acid in the presence of uridine 5'-diphosphoglucuronic acid and rabbit liver microsomes. The course of the biosynthetic reaction was followed by fluorimetry and reverse-phase, paired-ion high pressure liquid chromatography (HPLC). Also, the HPLC system was used to analyze for glucuronide and 3-hydroxybenzo[a]pyrene during the isolation procedure. The existence of a glucuronide of 3-hydroxybenzo[a]pyrene was determined by radiotracer and enzymic techniques, utilizing the HPLC system. Field desorption and direct inlet mass spectral techniques were used to characterize the 3-hydroxybenzo[a]pyrene glucuronide.  相似文献   
74.
Tazobactam was shown to be a potent inhibitor of group 1, 2a, 2b, and 2b' beta-lactamases. Extended kinetic studies with class A and C serine beta-lactamases showed that the PC1, TEM-2, and P99 enzymes all were reversibly inhibited prior to inactivation of the enzymes. The CcrA metallo-beta-lactamase was less well inhibited, with a 50% inhibitory concentration at least 3 orders of magnitude less favorable than those for most serine beta-lactamases. The numbers of hydrolytic turnovers of tazobactam before inactivation were 2 for PC1, 125 for TEM-2, 50 for P99, and 4,000 for the CcrA enzyme. In spectral studies, transient intermediates were formed after reaction of tazobactam with the PC1, TEM-2, and CcrA beta-lactamases, corresponding to enzyme-associated intermediates responsible for hydrolysis of tazobactam. Chromophores absorbing at 270 nm (CcrA) and 288 nm (TEM-2 and PC1) were observed for these reaction intermediates. The P99 cephalosporinase formed a stable complex with a UV maximum at 295 nm. Incubation of tazobactam with all of the enzymes resulted in accumulation of a tazobactam reaction product with a short-wavelength absorbance. This product has characteristics similar to those of the major eucaryotic metabolite of tazobactam. Possible reaction mechanisms are presented to explain the findings. In conclusion, both serine-based and metallo-beta-lactamases were irreversibly inactivated by tazobactam following an initial transient inhibition phase.  相似文献   
75.
Significantly higher (P < 0.05) thrombin-antithrombin III complex levels were found in the abdominal exudate of patients with peritonitis (median 5500 ng/ml) than in that of controls (median 89 ng/ml). In patients, peritoneal fluid concentrations of tissue and urokinase-type plasminogen activator were increased by factors of 65 and 10 respectively (P < 0.05). The concentration of plasminogen activator inhibitor (PAI) 1 was increased by a factor of about 800 (median 395 versus 0.5 ng/ml, P < 0.05). Despite markedly raised concentrations of PAI, peritoneal fluid displayed fibrinolytic activity as demonstrated by significantly increased (P < 0.05) concentrations of plasmin-alpha 2-antiplasmin complex (median 10,952 versus 57 ng/ml) and fibrin degradation products (median 40,360 versus 126 ng/ml). There was no correlation between plasma and peritoneal fluid concentrations. Intraabdominal coagulation and fibrinolysis are stimulated in the abdominal cavity of patients with bacterial peritonitis.  相似文献   
76.
PURPOSE: Laparoscopic surgery decreases postoperative pain, shortens hospital stay, and returns patients to full functional status more quickly than open surgery for a variety of surgical procedures. This study was undertaken to evaluate laparoscopic techniques for application to abdominal aortic aneurysm (AAA) repair. METHODS: Twenty patients who had AAAs that required a tube graft underwent laparoscopically assisted AAA repair. The procedure consisted of transperitoneal laparoscopic dissection of the aneurysm neck and iliac vessels. A standard endoaneurysmorrhaphy was then performed through a minilaparotomy using the port sites for the aortic and iliac clamps. Data included operative times, duration of nasogastric suction, intensive care unit days, and postoperative hospital days. Pulmonary artery catheters and transesophageal echocardiography were used in seven patients. For these patients data included heart rate, pulmonary artery systolic and diastolic pressures, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, and end diastolic area. Data were obtained before induction, during and after insufflation, during aortic cross-clamp, and at the end of the procedure. RESULTS: Laparoscopically assisted AAA repair was completed in 18 of 20 patients. Laparoscopic and total operative times were 1.44 +/- 0.44 and 4.1 +/- 0.92 hours, respectively. Duration of nasogastric suction was 1.3 +/- 0.7 days. Intensive care unit stay was 2.2 +/- 0.9 days. The mean length of hospital stay was 5.8 days excluding three patients who underwent other procedures. There were two minor complications, one major complication (colectomy after colon ischemia), and no deaths. For the eight patients who had intraoperative transesophageal echocardiographic monitoring, no changes were noted in heart rate, pulmonary artery systolic pressure, pulmonary capillary wedge pressure, and cardiac index. Pulmonary artery diastolic pressure and central venous pressure were greatest during insufflation without changes in end-diastolic area. Volume status, as reflected by end-diastolic area and pulmonary capillary wedge pressure, did not change. CONCLUSIONS: Laparoscopically assisted AAA repair is technically challenging but feasible. Potential advantages may be early removal of nasogastric suction, shorter intensive care unit and hospital stays, and prompt return to full functional status. The hemodynamic data obtained from the pulmonary artery catheter and transesophageal echocardiogram during pneumoperitoneum suggest that transesophageal echocardiography may be sufficient for evaluation of volume status along with the added benefit of detection of regional wall motion abnormalities and aortic insufficiency. Further refinement in technique and instrumentation will make total laparoscopic AAA repair a reality.  相似文献   
77.
A structured interview and standardized rating scales were used to assess a sample of 194 outpatients with schizophrenia in a regional Australian mental health service for substance use, abuse, and dependence. Case manager assessments and urine drug screens were also used to determine substance use. Additional measurements included demographic information, history of criminal charges, symptom self-reports, personal hopefulness, and social support. The sample was predominantly male and showed relative instability in accommodations, and almost half had a history of criminal offenses, most frequently drug or alcohol related. The 6-month and lifetime prevalence of substance abuse or dependence was 26.8 and 59.8 percent, respectively, with alcohol, cannabis, and amphetamines being the most commonly abused substances. Current users of alcohol comprised 77.3 percent and current users of other nonprescribed substances (excluding tobacco and caffeine) comprised 29.9 percent of the sample. Rates of tobacco and caffeine consumption were high. There was a moderate degree of concordance between case manager determinations of a substance-use problem and research diagnoses. Subjects with current or lifetime diagnoses of substance abuse/dependence were predominantly young, single males with higher rates of criminal charges; however, there was no evidence of increased rates of suicide attempts, hospital admissions, or daily doses of antipsychotic drugs in these groups compared with subjects with no past or current diagnosis of substance abuse or dependence. Subjects with a current diagnosis of substance use were younger at first treatment and currently more symptomatic than those with no past or current substance use diagnosis. The picture emerging from this study replicates the high rate of substance abuse in persons with schizophrenia reported in North American studies but differs from the latter in finding a slightly different pattern of substances abused (i.e., absence of cocaine), reflecting relative differences in the availability of certain drugs.  相似文献   
78.
Manipulation of the genetic machinery of cells both in vitro and in vivo is becoming an ever more important means of elucidating pathways of molecular and cellular biochemistry. In addition, gene therapy has been proposed as a novel and potentially powerful treatment for both inherited and acquired diseases. Successful gene transfer and gene blockade generally depend on high efficiency delivery of exogenous DNA or RNA into living cells, and much effort has therefore been focused on the development of methods for achieving this delivery in a safe and effective manner. We describe here our application of fusigenic Sendai virus (HVJ)-liposome technology toward the effective delivery of DNA into vascular smooth muscle cells (VSMC) in cell culture. Cellular uptake and intracellular distribution of oligodeoxynucleotide (ODN) after transfection with HVJ-liposome complexes was characterized using fluorescent (FITC)-labeled ODN, and the biologic effect of HVJ-liposome mediated transfection was demonstrated via inhibition of DNA synthesis in cultured VSMC using antisense ODN against basic fibroblast growth factor.  相似文献   
79.
Forty-five calves with artificial and pasture-acquired nematode infections were medicated with albendazole at dose levels of 0, 2.5, 5.0, or 10 mg/kg of body weight. A dose level of 2.5 mg/kg removed at least 99% of adult Trichostrongylus axei, Trichostrongylus colubriformis, Cooperia oncophora, and Bunostomum phlebotomum. Burdens of Haemonchus contortus, Strongyloides papillosus, and Ostertagia ostertagi were reduced 79, 88, and 97%, respectively. At a dose level of 5.0 mg/kg, at least 95% of all adult nematodes were removed; at 10 mg/kg, at least 97% were removed. At least 99% of 4th-stage larvae of O ostertagi, T axei, C oncophora and T colubriformis and 96% of H contortus were expelled at a dose level of 2.5 mg/kg. At 5.0 and 10 mg/kg, 99 to 100% of all species of larvae were removed. Trichuris spp adults were slightly susceptible at all dose levels; larvae were susceptible (83%) only at 10 mg/kg.  相似文献   
80.
Interleukin-12 (IL-12) is a heterodimeric cytokine produced by antigen-presenting cells that has the ability to induce gamma interferon (IFN-gamma) secretion by T and natural killer cells and to generate normal Th1 responses. These properties suggest that IL-12 may play an important role in the immune response to many viruses, including hepatitis B virus (HBV). Recently, we have shown that HBV-specific cytotoxic T lymphocytes inhibit HBV replication in the livers of transgenic mice by a noncytolytic process that is mediated in part by IFN-gamma. In the current study, we demonstrated that the same antiviral response can be initiated by recombinant murine IL-12 and we showed that the antiviral effect of IL-12 extends to extrahepatic sites such as the kidney. Southern blot analyses revealed the complete disappearance of HBV replicative intermediates from liver and kidney tissues at IL-12 doses that induce little or no inflammation in these tissues. In addition, immunohistochemical analysis demonstrated the disappearance of cytoplasmic hepatitis B core antigen from both tissues after IL-12 treatment, suggesting that IL-12 either prevents the assembly or triggers the degradation of the nucleocapsid particles within which HBV replication occurs. Importantly, we demonstrated that although IFN-gamma, tumor necrosis factor alpha, and IFN-alpha/beta mRNA are induced in the liver and kidney after IL-12 administration, the antiviral effect of IL-12 is mediated principally by its ability to induce IFN-gamma production in this model. These results suggest that IL-12, through its ability to induce IFN-gamma, probably plays an important role in the antiviral immune response to HBV during natural infection. Further, since relatively nontoxic doses of recombinant IL-12 profoundly inhibit HBV replication in the liver and extrahepatic sites in this model, IL-12 may have therapeutic value as an antiviral agent for the treatment of chronic HBV infection.  相似文献   
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