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71.
Abstract. Since the advent of a nondegradable controlled local delivery of antibiotics in 1979, several second generation systems have been developed. Second generation systems have attempted to improve on the early system. Chlorhexidine has been used effectively for over 30 years as an antiseptic. In the early 1970s, chlorhexidine gluconate was incorporated at 0.2% into mouthrinses in Europe and in 1986 it was incorporated at 0.12%, in a mouthrinse in the United States. Since these mouthrinses were effective in reducing the supragingival flora, had a high safety margin, and had no reported bacterial resistance, chlorhexidine offered a therapeutic advantage for a local delivery system. This system was developed and studied. This report will discuss this new biodegradable system containing chlorhexidine gluconate as the active agent (PerioChip®). Parmacokinetics of the system and a review of the multicenter studies in Europe and the United States are discussed. In these randomized clinical trials the chlorhexidine chip has been shown to enhance the effects of scaling and root planing. Chlorhexidine chip in conjunction with scaling and root planing, when compared to scaling and root planing alone, has shown significant improvement in probing pocket depth reduction, probing attachment level and bleeding on probing. This delivery system, in combination with scaling and root planing, has also resulted in significantly more probing depth reductions of 2 mm or more. The system is safe and efficacious. Placement of the chip is usually done in less than 1 min, it requires no retention system, biodegrades, and does not require a follow-up dental appointment.  相似文献   
72.
Abstract: In 1982 the IGCI CLL cooperative group decided to investigate the usefulness of treating, at diagnosis B-cell chronic lymphocytic leukemia (CLL) in early and stable phase of the disease. From January 1982 to December 1986, 148 patients were randomized either to receive immediate treatment with chlorambucil (CLB) or to defer therapy to the time of progression. The early and stable phase of the disease was defined by a total tumor mass (TTM) score < 9, the absence of anemia or thrombocytopenia and a doubling time > 12 months. The main end-point of the study was survival. At the last evaluation in April 1993, after a median follow-up of 75 months, no significant difference was found in overall survival between early vs. deferred treatment patients from every cause of death as well as from death due to CLL-related causes only. The same results were obtained when the patients in more favorable stages, such as Binet stage A and TTM < 4.5, were considered. Interestingly, the incidence of epithelial cancer was similar in the two groups. Early treatment was associated with a significantly better response and a lower progression rate. From this long-term experience, it can be concluded that immediate chemotherapy with CLB is not beneficial for CLL patients in early and stable phase of the disease in terms of survival.  相似文献   
73.
From January 1986 to December 1989, 157 previously untreated patients, with Hodgkin's disease stage I or II without bulky disease, were enrolled in a clinical comparative study. The objectives of the study were to compare the efficacy and safety of using epirubicine or mitoxantrone instead of adriamycin in the combination chemotherapy regimen ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine). The complete response rate was better in the patients treated with the ABVD or EBVD regimens compared to the MBVD arm. Also, differences in overall survival and relapse-free survival were better in the patients who received ABVD or EBVD compared to the MBVD regimen. Hematological, gastrointestinal and cardiac toxicity were similar in the three groups. Dose intensity, delays and complications were also similar in the three groups. The mitoxantrone-containing regimen was found to have less efficacy in comparison to the other regimens tested in the present study in patients with favorable stage I or II Hodgkin's disease. © 1995 Wi1ey-Liss Inc.  相似文献   
74.
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
75.
We reviewed the records of 110 consecutive patients with advanced-stage epithelial ovarian carcinoma treated at the Soroka Medical Center, Beer-Sheva, Israel, from 1961-1987. Twenty patients (18.1%) had optimal debulking at initial laparotomy, 30 patients (27.2%) had nonoptimal debulking at initial laparotomy, 20 patients (18.1%) had an "inoperable" disease at initial laparotomy, and 40 patients (36.3%) had such poorly written records that no information about the degree of resectability at initial laparotomy could be obtained. Four patients, in whom the residual tumor left at initial laparotomy had responded to chemotherapy, had a second laparotomy. In all four patients optimal debulking surgery at second laparotomy was easy to perform and was successful. The value of a second laparotomy after a few cycles of chemotherapy in order to optimally debulk the residual tumor left at initial laparotomy is discussed. It is concluded that a second attempt of debulking surgery after chemotherapy has a respectable place in the management of patients with advanced-state epithelial ovarian carcinoma, but further research is needed.  相似文献   
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Fatigue is the most common side effect of chemotherapy for cancer. Not yet explored is the possibility that patients may develop conditioned fatigue responses to clinic cues as a result of the repeated pairing of the clinic environment (conditioned stimulus) with infusions of chemotherapy (unconditioned stimulus) that cause fatigue (unconditioned response). As a first critical test of this possibility, breast cancer patients (N = 82) were studied across their first four cycles of chemotherapy. Consistent with conditioning: (1) fatigue levels in the clinic environment significantly increased with repeated pairings of the clinic environment and chemotherapy administration; (2) fatigue responses in the clinic environment prior to the fourth infusion (CR) were predicted by patients’ previous experiences of post-infusion fatigue (UR) above and beyond effects of concurrent emotional distress. These results provide the first evidence in the literature that fatigue can be conditioned. Additional research is warranted to determine the clinical importance of this source of fatigue in chemotherapy patients.  相似文献   
79.
Testicular cancer is the most common neoplasia occurring in the young male population. The PEB (cisplatin, etoposide and bleomycin) adjuvant chemotherapy usually proposed after orchidectomy in non seminomatous tumours, and in metastatic seminomas, has improved the long-term survival of these patients. Following an azoospermic period, sperm cell recovery is generally observed after treatment delivery, but little is known about the genetic consequences on these new spermatozoa. To estimate the chromosomal consequences of this chemotherapy on sperm cells during the period of recovery of spermatogenesis, sperm cell aneuploidy was studied in testicular cancer patients, at 6-18 months after PEB adjuvant chemotherapy delivery, using fluorescence in-situ hybridization (FISH) of chromosomes 7, 16, 18, X and Y with specific DNA probes. A significant increase in the frequency of diploidy and disomy for chromosomes 16, 18 and XY was observed in treated patients compared with a healthy control group. Spermatozoa aneuploidy occurring during the spermatogenesis recovery period might be a possible side effect of the PEB regimen. Thus, practitioners should be advised to provide counselling about the need for an appropriate duration of contraception. Moreover, genetic counselling should be offered in cases of pregnancy occurring soon after the end of chemotherapy.  相似文献   
80.
Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant.  相似文献   
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