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The service life of herbicide-resistant varieties can be prolonged by identification of intercrossing-resistance of existing herbicide-resistant rapeseed and the screening of application of other safe herbicide in dosage forms. In this study7 a new germplasm PN19 and transgenic plants of Arabidopsis and tobacco resistant to SU herbicides were used as materials. Five classes of ALS inhibitory herbicides with five concentration gradients were sprayed at 3-5 leaf stage of rapeseed. The intercrossing-resistance of PN19 to five herbicides was determined by resistance identification. Results showed that plant intercrossing-resistance against SU and SCT class was the strongest' followed by IMI and TP class7 whereas that against PB class was the lowest. Evaluation of herbicide intercrossing-resistance in transgenic plants and analysis of in vitro activity of tobacco ALS enzymes revealed this resistance function to various herbicides was resulted from the decreased sensitivity of target ALS enzymes to herbicides. In addition' the expression of PN19 herbicide-resistance gene after treatment with five herbicides was higher than that of wild type. The study provides an opportunity by mixing use of ALS herbicides to integratedly control weeds in the field. [ABSTRACT FROM AUTHOR]

Objective: To study the nephrotoxicity induced by first oral administration of tacrolimus (FK506) and the prevention of diltiazem (Dil)., Methods: 24 Sprague-Dawley male rats were randomly divided into 4 equal groups: control (n = 6), cyclosporine A (CsA) group (receiving CsA 25 mg.kg(-1).d(-1) so as to develop CsA-induced nephropathy model), FK506 group (receiving FK506 0.8 mg.kg(-1).d(-1), the common renal transplantation therapeutic dose, so as to develop FK506-induced nephropathy model), FK506 + Dil group (receiving CsA 0.8 mg.kg(-1).d(-1) and Dil 8 mg.kg(-1).d(-1)), and control group. Four weeks later body weight was measured, blood samples were collected to examine the creatinine, urea nitrogen, and uric acid, and urine samples were collected to examine the 24 h urine protein, uric acid, and creatinine. Then the rats were killed with their kidneys taken out to undergo histopathological examination., Results: The urine creatinine levels of the CsA and FK506 groups were significantly lower than that of the control group (both P < 0.05), however, there was no significant difference in urine creatinine between the FK506 + Dil group and control group. The blood creatinine levels of both CsA and FK506 groups were significantly higher than those of the FK506 + Dil group and control group (all P < 0.05), however, there was no significant difference in blood creatinine between the FK506 + Dil group and control group. The urea nitrogen level of the CsA group was significantly higher than those of the other 3 groups (all P < 0.05). The creatinine clearance rates of the CsA and FK506 groups were both significantly lower than that of the control group (both P < 0.05), and the creatinine clearance rate of the FK506 + Dil group was between those of the FK506 group and control group, however, with significant differences with both of them. Histopathology examination showed cloudy swelling and vacuolization of the renal tubular epithelial cells in the CsA and FK506 groups. However, the pathological changes of the FK506 + Dil group were remarkably milder in comparison with these 2 groups., Conclusion: FK506 and CsA at the renal transplantation therapeutic dose induce nephrotoxicity. Diltiazem prevents FK506-induced nephrotoxicity.