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11.
In order to investigate the clinical factors that might influence the diversity and the degree of Candida species carriage in saliva, we conducted a cross-sectional study with 133 patients with complaints of xerostomia. Anamnesis, oral examination and collection of chewing-stimulated whole saliva were performed. The samples of saliva were kept refrigerated until they were plated onto CHROMagar Candida; cfu were counted and Candida species were identified by standard methods. There was a high prevalence of mixed Candida colonization. No relationship was found between total Candida cfu counts and variables like gender, age, place of origin, underlying diseases, exposure to medications (except antibiotics), daily habits and salivary flow rates. Oral candidiasis, antibiotic exposure and dental prosthesis wearing were associated with relatively high Candida counts in saliva. Low salivary flow rates predisposed to intense colonization by C. albicans and C. parapsilosis.  相似文献   
12.
A case-control study was undertaken to identify risk factors for typhlitis in patients with hematological malignancies. A data base file with a total of 410 episodes of fever and neutropenia in patients cared for between May 1987 and 1996 was reviewed. Typhlitis was defined as a symptom complex of fever, intense abdominal pain and tenderness in the presence of neutropenia. Five cases of typhlitis were identified. Three controls for every patient were randomly selected from the same cohort. Diarrhea and jaundice were more frequent in patients than in controls (p=0.03). The presence of mucositis, prolonged duration of profound neutropenia and idarubicin treatment proved to be risk factors for typhlitis.  相似文献   
13.
To assess the efficacy of quinolones in the prophylaxis of infections in neutropenic patients with acute non-lymphocytic leukemia, and to evaluate the emergence of quinolone resistance in two University Hospitals in Brazil, we retrospectively compared 101 consecutive episodes of neutropenia managed with quinolone prophylaxis between 1989 and November 1993, and 26 previous episodes without prophylaxis, and reviewed the results of in vitro sensitivity of Gram-negative strains to quinolones in the same period. Prophylaxis with quinolones resulted in less episodes of bacteremias (21% vs. 69%, p=10(-7)), including Gram-negative bacteremias (6% vs. 38%, p=10(-5)), with no statistically significant difference in the death rate (18% vs. 31%, p=0.14, 95% confidence interval -6-32). The resistance of Gramnegative strains to quinolones rose from 7% to 18% between 1990 and 1993 (p=10(-5)). The resistance against ceftazidime and amikacin, the agents used in the empirical antibiotic therapy, increased in the same proportion as the quinolones. Given the limited benefit of quinolones as prophylaxis and the increasing number of quinolone-resistant Gram-negative strains observed in our hospitals, the use of quinolones as prophylaxis must be seriously questioned. A stricter control of the use of quinolones in these hospitals might decrease resistance.  相似文献   
14.
The resistance of cancer cells to anti-neoplastic agents is a major attribute of malignancy. Kinetic drug resistance develops as the tumor burden increases, and is reversible when the cell mass can be reduced. Genetic drug resistance, in contrast, results in the acquisition of possibly irreversible resistance by random cell mutation. The latter mechanism, and one of its corollaries, that rapidly alternating drug regimens could prevent the advent of new resistant cell lines, have been the subject of many studies in the last decade. The endpoint to evaluate in such studies should be an increase in failure-free survival, since such prevention cannot have any influence in the complete remission rates. A review of the clinical trials in Hodgkin's disease suggests that failure-free survival rates are in fact improved with the alternating schedules. On the other hand, dose-intensification is presently under study as a means of overcoming kinetic drug resistance, thereby increasing the complete remission rates, and has recently proved effective in the prolongation of survival in different malignancies. Further understanding of the mechanisms of drug resistance and the prospective appraisal of the combination of both high-dose therapy and alternating drug treatments should result in a better outcome, mostly for patients with large tumor burdens or other high risk factors.  相似文献   
15.
Two sets of benzotriazinone and benzoyltriazole derivatives were prepared and tested for local anaesthetic activity in comparison with lidocaine. Several of the prepared compounds exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an aromatic system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compounds of the series was also assessed. Compound 1b, which has an anaesthetic activity comparable to that of lidocaine, was also characterized by a more favourable therapeutic index. All compounds were tested in vitro to evaluate their negative chronotropic action in isolated rat right atria.  相似文献   
16.
Review article: cardiac adverse effects of gastrointestinal prokinetics   总被引:8,自引:0,他引:8  
Gastrointestinal prokinetics, such as metoclopramide, cisapride and levosulpiride, are widely used for the management of functional gut disorders. Recently, several studies have shown that cisapride (a partial 5-HT4 receptor agonist) can induce dose-dependent cardiac adverse effects, including lengthening of the electrocardiographic QT interval, syncopal episodes and ventricular dysrhythmias. Until recently, it was not clear whether these effects were dependent on 5-HT4 receptor activation or related to peculiar characteristics in the molecular structure of single agents within the benzamide class. Experimental evidence now favours the second hypothesis: cisapride possesses Class III antiarrhythmic properties and prolongs the action potential duration through blockade of distinct voltage-dependent K+ channels, thus delaying cardiac repolarization and prolonging the QT interval. Patients at risk of cardiac adverse effects are children, subjects with idiopathic, congenital or acquired long QT syndrome and, in particular, those receiving concomitant medication with Class III antiarrhythmic agents, some H1-receptor antagonists (e.g. terfenadine), or drugs such as azole antifungals (e.g. ketoconazole, itraconazole, miconazole and fluconazole) and macrolide antibacterials (e.g. erythromycin, clarithrod-mycin and troleandomycin), which can inhibit cisapride metabolism by interfering with the CYP3A4 isoenzyme.  相似文献   
17.
The epithelial cells of ovarian mucinous carcinomas may sometimes appear similar to those of gastrointestinal or endocervical mucinous carcinomas, but most are composed of cells that do not suggest any particular derivation. We report four cases of mucinous ovarian carcinoma in which the cells were entirely or almost entirely endocervical-like. The patients' ages were 34, 43, 44, and 50 years. Two patients had bilateral tumors confined to the ovaries at initial staging; both also had synchronous endometrial carcinomas of the mucinous type. The two other patients had unilateral tumors, both with invasive metastases in the pelvis and abdomen at initial staging. In one of the latter cases a mullerian (endocervical-like) mucinous borderline tumor (MMBT) of the opposite ovary had been removed 5 years earlier, and in this case and two other cases the ovarian carcinomas had foci resembling MMBT, suggesting that they may be an invasive counterpart to these tumors. The six tumors ranged from 4 to 19 cm; five were grossly cystic with papillary or solid areas, and one was entirely solid. They were composed of closely packed glands, cysts, and cysts containing complex papillae. There was abundant intraglandular and intracystic mucin. The epithelial cells were well differentiated with infrequent mitoses and most were tall with mucinous cytoplasm resembling normal endocervical glandular cells. In three tumors there also were round to polygonal cells with eosinophilic cytoplasm; endometrioid foci were present in three tumors and a squamous focus was present in one. One tumor had a focally infiltrative growth pattern with a desmoplastic stromal reaction; the remaining five tumors had an exclusively confluent (expansile) pattern of invasion. Endometriosis was present in residual ovarian tissue adjacent to four tumors in three patients and had marked epithelial proliferation in three. All patients were treated postoperatively with chemotherapy and were without clinical recurrence with follow-up intervals of 8 months, 1.2 years, 2.9 years, and 3.8 years. By immunohistochemical analysis the neoplastic epithelium was positive for estrogen and progesterone receptor proteins, vimentin, and cytokeratin 7, and negative or only focally positive for carcinoembryonic antigen and cytokeratin 20, a profile that differs from that of the usual mucinous ovarian carcinoma and is supportive of a mullerian derivation. As with MMBTs, there was a strong association with endometriosis, and these tumors likely arise from endometriosis, possibly through an MMBT precursor in some cases. To better understand their clinicopathologic features and pathogenesis, this uncommon variant should be separated from the usual type in future studies of mucinous carcinomas of the ovary.  相似文献   
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Objectives: The objective of this research was to evaluate the efficacy of a new antifungal imidazole, dapaconazole tosylate, in the treatment of Pityriasis versicolor (PV).

Design and methods: Sixty patients with clinical and mycological diagnosis of PV were randomly assigned to receive either 1 g dapaconazole tosylate 2% cream or 1 g ketoconazole 2% cream. Treatments were applied once a day for 28 days. A dermatologist evaluated efficacy and safety daily, and weekly laboratorial tests were performed. The primary end point was a clinical and mycological cure of lesions after 28 days of treatment. The secondary end point was the time to clinical healing assessed by Kaplan–Meier analysis and Log-rank testing.

Results: Fifty-three patients adhered to protocol rules. Clinical and mycological cure was achieved in 84.6% (22/26) and 92.6% (25/27) of patients treated with ketoconazole and dapaconazole, respectively (difference [effect size] = 8.0%, Standard error of difference: 8.69%, 95% CI: –6.3 to 22.3%). Median time to healing was 23.5 and 21 days for ketoconazole and dapaconazole, respectively (p = 0.126). Adverse events occurred only in ketoconazole-treated patients (13%; 4/30).

Conclusion: Dapaconazole tosylate is non-inferior to ketoconazole when used at a dose of 20 mg/day for 28 consecutive days for the treatment of PV. Dapaconazole also demonstrated a good safety profile.  相似文献   

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