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991.
In rats undergoing unilateral extirpation of the pelvic ganglion, the adrenergic innervation disappeared on the ipsilateral side of the urinary bladder. It had reappeared after 6--9 weeks. 相似文献
992.
Dopamine (DA) failed to stimulate the adenylate cyclase of the mesolimbic A10 DA nerve cell body area, in contrast to tis activating effect in the nigrostriatal A9 DA cell body area. The enzyme was stimulated by GMPPNP (a GTP analog) and NaF. This indicates the absence in the A 10 cell area of DA receptors with functional coupling on adenylate cyclase, in contrast to the A9 cell area where such DA receptors are believed to be located on afferent axon terminals. 相似文献
993.
Using the pH (buffered) sensitivity discs for the agar-diffusion bioassay of aminoglycoside antibiotics, characteristic response curves were obtained. Since the nature of the activities observed are structure-related, this method can serve as a useful aid for primary identification of members of this class of antibiotics. 相似文献
994.
The effect of gamma-rays on iron-free conalbumin was studied by isoelectric focusing technique. The results obtained can be interpreted on the basis of radiation-induced conformational changes of the macromolecules through a cleavage of disulphide bridges. Treatments with reagents acting on disulphide bridges lead to isoelectric focusing patterns that confirm this hypothesis. 相似文献
995.
The presence of hydrocortisone in virus-infected cell cultures leads to enhancement of the syncytia forming ability of Newcastle disease virus and to production of vescicular stomatitis virus particles which loose their infectivity upon storage below 0 degrees C. 相似文献
996.
The formation of lipofuscin pigment in the anterior horn cells of the cervical spinal cord has shown in the fetuses and neonates under the extrinsic influence of maternal protein deprivation during the gestation period in the squirrel monkeys. 相似文献
997.
Stimulation of the nucleus accumbens evokes a potent inhibition in neurons of the ventral tegmental area. GABA is likely to act as a transmitter in this descending inhibitory system. 相似文献
998.
Sister chromatid exchange was studied in lymphocyte and fibroblast cultures. Alcohol caused no disturbance under normal conditions but an acetaldehyde level above 40 muM inhibited cell multiplication and elevated SCE considerably. A high acetaldehyde level is thought to elicit the fetal alcohol syndrome, a view supported by clinical and experimental observations. 相似文献
999.
A new protein, of molecular weight 160,000, was isolated from the skin venom of the crested newt and partially characterized by bioassays and biochemical methods. This protein shows the same functional properties as the crude venom, which produces convulsions in mice and is cytotoxic. 相似文献
1000.