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Summary Deaza-aminopterin is a folate analog which is transported more rapidly than methotrexate into cells and appears to be more active than methotrexate against human and animal tumor in vitro. Fifteen patients with advanced urothelial tract cancer were given deaza-aminopterin 30–37.5 mg/m2 IV QW. In responding patients drug was given QOW after 4–6 consecutive doses. Doses were escalated or de-escalated by 7.5 mg/m2 depending on toxicity. Twelve patients had received prior chemotherapy which included methotrexate in nine. Three patients achieved a partial remission lasting 1, 3, and 3 months respectively: all responders had previously failed methotrexate after an initial response to a methotrexate containing regimen. None of the six patients who were methotrexate naive responded to deaza-aminopterin; 3 subsequently received methotrexate without response. Mild mucositis was universal and in 5 was severe. Six patients had an increase in liver transaminases probably secondary to anti-folate hepatotoxicity. Other toxicities included diarrhea, nausea, skin rash and fever. Further studies are needed to define the precise efficacy of deaza-aminopterin in patients with urothelial tract cancers.  相似文献   
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The scope of our research is the development of polymer-based bioabsorbable stents for urologic applications and in vitro testing of tissue reactions of cultured ureteral and urethral segments induced by implanted polymer stent prototypes. For these purposes a tissue cultivation model was developed using selected techniques of tissue engineering. Essential advantages of degradable over nondegradable urethral stents are elimination of the adverse extraction of epithelialized stents and the potential for recovery of organ-specific functionality. Moreover, the biocompatibility of a degradable urethral stent could potentially reduce the risk of restenosis due to hyperplasia and could be used, even repeatedly, for the treatment of a number of subvesical obstructions. For the treatment of tumor-induced strictures, application of degradable polymer stents coated with cytostatic drugs may be possible. The mechanical effect of the drug-loaded stent as a “place holder” could be complemented by adjuvant or palliative approaches such as local chemotherapy. We have developed and tested in vitro a degradable urethral stent incorporated with the model drug methotrexate for local drug delivery (LDD) by diffusion and during stent degradation.  相似文献   
4.
Summary Twenty-three patients with advanced renal cell cancer were treated with Didemnin B. One partial response was achieved (5%) in 21 evaluable patients. An allergic reaction was noted in four patients including one patient with anaphylaxis. Didemnin B is not recommended in the treatment of renal cell carcinoma.  相似文献   
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Demonstration of malignant cells in blood specimens collected during transurethral resection of the prostate (TURP) has implicated TURP in the dissemination of prostatic cancer. Of 153 patients who underwent radiation therapy for prostate cancer between January 1977 and June 1990 and were retrospectively analyzed, 93 were evaluable. Fifty-nine patients required TURP before radiation therapy for prostatic obstruction (BPH and/or cancer); the remaining 34 patients underwent radiation therapy after fine-needle aspiration biopsy. No statistically significant difference in failure rate could be detected between these groups, with a failure rate of 47% (28 of 59 patients) at a median follow-up time of 49 months (range, 8 to 146 months) in the TURP group versus a failure rate of 47% (16 of 34 patients) at a median follow-up time of 50 months (range, 3 to 122 months) in the group who underwent biopsy only (Fisher's exact test, P = 0.23). Within the confines of this retrospective study, it appeared that TURP did not enhance the development of metastatic disease.  相似文献   
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We examined determinants of nonvertebral fracture in elderly men from six U.S. communities followed an average of 4.1 years. Six clinical risk factors predicted fracture risk independent of hip BMD: tricyclic antidepressant use, previous fracture, inability to complete a narrow walk trial, falls in previous year, age > or =80 years, and depressed mood. INTRODUCTION: There are few prospective studies of fracture determinants in men. We examined the associations between a comprehensive set of clinical risk factors and risk of nonspine fracture in older men and whether determinants of fracture risk were independent of total hip BMD. MATERIALS AND METHODS: A total of 5995 men > or =65 years of age were recruited from six communities in the Unites States and followed prospectively for an average of 4.1 years. Baseline assessments of demographic, lifestyle, medical history, functional status, anthropometry, and cognitive, visual, and neuromuscular function were assessed by questionnaire or examination. Triannual mailed questionnaires ascertained incident fracture; reported fractures were adjudicated by physicians using medical records and X-ray reports. Proportional hazards models were used to develop multivariable models, selecting variables and controlling for BMD. RESULTS: Of 5876 men, 4.7% (N = 275) reported an incident nonspine fracture during follow-up (11.46/1000 person-years). Tricyclic antidepressant use (hazard ratio [HR], 2.36; 95% CI, 1.25-4.46), history of fracture at or after age 50 (HR, 2.07; 95% CI, 1.62-2.65), inability to complete a narrow walk trial (HR, 1.70; 95% CI, 1.23-2.34), falls in previous year (HR, 1.59; 95% CI, 1.23-2.05), age > or =80 years (HR, 1.33; 95% CI, 1.01-1.76), depressed mood (HR, 1.72; 95% CI, 1.00-2.95), and decreased total hip BMD (HR, 1.53; 95% CI, 1.34-1.74) were independently related to increased risk. Compared with having none (48.0% of men), having three or more of the clinical risk factors (4.9% of men) increased fracture risk 5-fold, independent of BMD. Having three or more risk factors and being in the lowest tertile of BMD was associated with a 15-fold greater risk than having no risk factors and being in the highest BMD tertile. CONCLUSIONS: Several clinical risk factors were independently associated with nonspine fractures in elderly men. The combination of multiple risk factors and low BMD was a very powerful indicator of fracture risk.  相似文献   
7.
Serosorting (i.e., engaging in unprotected sex with partners known to be of the same serostatus) can be a difficult process for men who have sex with men (MSM) who frequently make assumptions about their partners' serostatus. This process can be further complicated by a partner's dishonesty as well as other individual and contextual factors. The present study specifically examined how assumptions of serostatus made about unknown serostatus partners impact on the sexual behavior of 110 alcohol-abusing HIV-positive MSM. Although previous research has shown that HIV-positive MSM are more likely to serosort with other known HIV-positive men than with known HIV-negative men, our data suggest that unprotected sex behavior may not be specifically driven by whether or not they made assumptions of seroconcordance or serodiscordance. The types of assumptions these HIV-positive MSM made about their unknown status sexual partners and the basis for such assumptions were also examined. Owing to the ambiguities involved in assumptions of a partner's serostatus in sexual encounters, the 'unknown status' partner category is analytically distinct from 'known status' categories, and needs to be more fully explored because of its impact on perceived serosorting, rather than actual serosorting, among HIV-positive men.  相似文献   
8.
Suffering is a phenomenon with physical and emotional components. Although several studies have drawn attention to the needs of, and demands placed on families who provide care for patients with a diagnosis of cancer at home, few have discussed the suffering which many of these caregivers experience. This paper will illustrate the phenomenon of suffering as seen in the responses made by family caregivers of patients with cancer. Eighty-three family caregivers drawn from a probability sample of patients with a diagnosis of cancer were interviewed in their homes to determine needs they encountered in their caregiving roles. The caregivers consisted of 43 males and 40 females, with mean ages of 53 and 54 years respectively. Families not only identified their needs, they also indicated several areas which were for them sources of suffering. The findings revealed that family suffering often stemmed from fear of loneliness; uncertainty about the future (their own and that of the patients); lifestyle disruption; communication breakdown; lack of support; and their sense of helplessness. These findings suggest that health professionals, particularly nurses, who work with families in their homes, must be alert and sensitive to cues and circumstances which could indicate suffering, and in so doing, take the necessary steps to ameliorate their situation.  相似文献   
9.
A case report of epithelioid adrenal angiosarcoma is presented. Tumor cells showed expression of cytokeratin, Factor VIII-related antigen, Ulex europaeus agglutinin-I, and vimentin. The patient also was found to have mesenteric fibromatosis (abdominal desmoid tumor) and an elevated serum level of estradiol. The authors discuss the unique appearance of these rare tumors, their relationship to hyperestrinism, and review the recent data in the literature showing cytokeratin expression by malignant epithelioid vascular tumors.  相似文献   
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