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301.
O bjectives : To evaluate the response of measurable canine mast cell tumours unsuitable for other treatment modalities to a chemotherapy protocol comprising chlorambucil and prednisolone.
M ethods : Dogs bearing measurable mast cell tumours, unsuitable for treatment by surgery or radiotherapy, were treated with orally administered prednisolone and chlorambucil, and their responses assessed.
R esults : Twenty-one dogs were enrolled in the study; 13 had intermediate-grade mast cell tumour, six were high grade and two were diagnosed by cytology alone. Eight dogs had multiple tumours and 13 dogs had single tumours, and six dogs had lymph node metastases and no dogs had visceral metastases detected. Three dogs achieved complete remission, five achieved partial remission (overall response rate 38 per cent), nine had static disease and four dogs had progressive disease. Median progression-free interval for the eight responders was 533 days, and median survival time for all dogs in the study was 140 days. Progression-free interval and median survival time were not influenced by the age, sex, weight or neutering status of the patient, by the grade or stage of the tumour or whether the patient had single or multiple tumours. No toxicity was detected.
C linical S ignificance : Response and survival rates of inoperable canine MCT to chlorambucil and prednisolone are comparable to previously described protocols, with no apparent toxicity. 相似文献
M ethods : Dogs bearing measurable mast cell tumours, unsuitable for treatment by surgery or radiotherapy, were treated with orally administered prednisolone and chlorambucil, and their responses assessed.
R esults : Twenty-one dogs were enrolled in the study; 13 had intermediate-grade mast cell tumour, six were high grade and two were diagnosed by cytology alone. Eight dogs had multiple tumours and 13 dogs had single tumours, and six dogs had lymph node metastases and no dogs had visceral metastases detected. Three dogs achieved complete remission, five achieved partial remission (overall response rate 38 per cent), nine had static disease and four dogs had progressive disease. Median progression-free interval for the eight responders was 533 days, and median survival time for all dogs in the study was 140 days. Progression-free interval and median survival time were not influenced by the age, sex, weight or neutering status of the patient, by the grade or stage of the tumour or whether the patient had single or multiple tumours. No toxicity was detected.
C linical S ignificance : Response and survival rates of inoperable canine MCT to chlorambucil and prednisolone are comparable to previously described protocols, with no apparent toxicity. 相似文献
302.
Abrupt shift in subsurface temperatures in the tropical pacific associated with changes in El Nino 总被引:1,自引:0,他引:1
Radiocarbon (14C) content of surface waters inferred from a coral record from the Galapagos Islands increased abruptly during the upwelling season (July through September) after the El Nino event of 1976. Sea-surface temperatures (SSTs) associated with the upwelling season also shifted after 1976. The synchroneity of the shift in both 14C and SST implies that the vertical thermal structure of the eastern tropical Pacific changed in 1976. This change may be responsible for the increase in frequency and intensity of El Nino events since 1976. 相似文献
303.
Studies were conducted to understand the relationship, if any, between the amount and pattern of milk yield and the occurrence of cystic ovarian disease (COD) in dairy cattle. More than 70 cows with cysts were compared with herd mates of similar lactation number. Total milk yield in lactations when cysts occurred and in the preceding lactations were not different from the corresponding lactations in control cows. Patterns of monthly milk yield did not differ between the two groups of cows. However, weekly analysis in early lactation revealed differences. Both groups of cows achieved peak yields at a similar time (5.4 +/- 1.2 vs 5.7 +/- 1.9 weeks post partum in normal vs cows with COD). However, owing to an early decline in yield of cows with COD, their duration of peak yield was significantly shorter (P less than 0.05) than in the control cows (3.2 +/- 2.2 vs 5.6 +/- 2.4 weeks). Both the attainment and the decline of peak yield occurred 5.6 (range = 2-15) weeks before the cysts were diagnosed. It is concluded that COD is not particularly a disease of higher yielding cows and that COD has no discernible effect on the milk yield or its pattern. It is speculated, however, that some cows in early lactation, while trying to meet the requirements of sustained peak milk production, are more susceptible to minor environmental changes (such as new social interactions, or changes in diet). These events may lead to a drop in milk production and disruption of events controlling normal ovulation, resulting in the formation of ovarian cysts. 相似文献