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991.
A series of (4,4-difluoro-1,2,3,4-tetrahydro-5H-1-benzazepin-5-ylidene)acetamide derivatives was synthesized, and their structure–activity relationships were examined in order to identify potent and selective arginine vasopressin V2 receptor agonists. Attempts to substitute other chemical groups in place of the 2-pyridilmethyl moiety of 1a led to the discovery that potent V2 binding affinity could be obtained with a wide range of functional groups. This structural tolerance allowed for the manipulation of other attributes, such as selectivity against V1a receptor affinity or avoidance of the undesirable inhibition of cytochrome P450 (CYP), without losing potent affinity for the V2 receptor. Some representative compounds obtained in this study were also found to decrease urine volume in awake rats.  相似文献   
992.
993.
Sleep and Biological Rhythms - Appropriate warming of the periocular or posterior cervical skin has been reported to induce autonomic or mental relaxation in humans. To clarify the effects of...  相似文献   
994.
 Several simple methods of DNA preparation from plant tissues were evaluated for PCR-RFLP analyses of SLG and SRK alleles, which can be used for the identification of S haplotypes of breeding lines in broccoli and cabbage (Brassica oleracea L.) and in purity tests of F1 hybrid seeds. On the five methods tested, the NaI method was found to be the most suitable for the amplification of the SLG and SRK alleles. This method enables the use of a single seed as testing material. Using this method, we identified S haplotypes of 31 broccoli and 31 cabbage cultivars. Ninety-four percent of the cultivars of broccoli and 97% of those of cabbage were-single cross F1 hybrids. Nine and 15 S haplotypes were found in broccoli and cabbage, respectively. The small number of S haplotypes in broccoli suggests the importance of incorporating new S haplotypes in the breeding program. Received: 18 February 1999 / Revision received: 4 May 1999 / Accepted: 14 May 1999  相似文献   
995.
Ultrastructural investigations on many isolates ofTetraselmis have revealed that the species have characteristic fine structural features of the pyrenoid and it was proposed (Horiet al., 1982) that the genus be subdivided into four subgenera. In the present study of this series, species of the subgenusPrasinocladia, includingTetraselmis marina, T. verrucosa andT. verrucosa f.rubens, are described in detail.  相似文献   
996.
Chloroplasts which were rapidly isolated from illuminated leaves showed activity of ATP hydrolysis at a level much higher than that of the dark control. Under the high-intensity illumination or under repetitive flash excitation, the activated chloroplasts synthesized more ATP than those with a low ATP hydrolysis activity. Δ\?gmH+ formed under repetitive flashes was smaller in the activated chloroplasts than in the inactive chloroplasts. The inhibition of ATP yield per flash by valinomycin or nigericin in the presence of K+ was stronger in the inactive chloroplasts than in the activated chloroplast. ATP synthesis in the activated chloroplasts seems to have a lower Δ\?gmH+ threshold.  相似文献   
997.
Two new species ofAcer fossil woods,A. momijiyamense andA. Watarianum, are described and a short review of fossil wood of this genus from the Tertiary of Japan is given. In the course of a study on three fossil wood species which have been described asAcer andAcernium from Japan, it is noticed thatAcernium iwatense Watari does not belong toAcer but toPrunus of the Rosaceae, and is therafore transferred intoPrunus asPrunus iwatense comb. nov.  相似文献   
998.
Pretreatment of pancreatic acini with vasoactive intestinal peptide (VIP) or secretin for 120 min reduced subsequent [125I-Tyr1]somatostatin binding to membranes prepared from these acini, with a maximally reduced binding being 79.2% or 77.4% of control, respectively. In addition, exogenously added cyclic AMP derivatives or a phosphodiesterase inhibitor mimicked the effect of VIP or secretin. Scatchard analysis of [125I-Tyr1]somatostatin binding demonstrated that the decrease in the labeled somatostatin binding induced by VIP or dibutyryl cyclic AMP (dbcAMP) pretreatment was due to the decrease in the maximum binding capacity without a significant change in the binding affinity. The effect of simultaneous pretreatment of acini with VIP and carbamylcholine (carbachol) on subsequent labeled somatostatin binding appeared to be almost equal to the calculated additive value for each peptide. Results obtained, therefore, indicate that the binding of somatostatin to its receptors in the pancreas may be regulated via two functionally distinct pathways.  相似文献   
999.
Improved fish lymphocyte culture for chromosome preparation   总被引:5,自引:0,他引:5  
Cytogenetic methodology is still underdeveloped in fishes compared with mammals. Culture condition for fish lymphocytes was optimized to improve chromosome preparation using the rainbow trout (Oncorhynchus mykiss) as a model after changing the combination of parameters such as mitogens, incubation periods, media, cell components, and freshness of blood. The optimized culture condition included isolation of lymphocytes from fresh blood by a stirring method, their culture in medium 199 supplemented with 10% FBS, 18g/ml of phytohemagglutinin (PHA-W) and 100g/ml of lipopolysaccharide (LPS) as mitogens, and harvested at 6 days after culture. This condition provided a notably increased mitotic index (MI) of 4.3–10.0% in rainbow trout lymphocytes. In addition, the condition was highly reproducible as shown by the similar level of MI in cultured lymphocytes from 181 individuals without failure. Applicability of this method in a wide range of fish groups was also proven with MI of 1.1–13.3% in cultured lymphocytes from other 16 freshwater species of Acipenseridae, Anguillidae, Salmonidae, Cyprinidae, and Centrarchidae, and five marine species of Sparidae, Kyphosidae, Paralichthyidae, and Scorpaenidae. Chromosome preparations of improved quality by the present method were successfully applied for the replication R-banding with incorporation of 5-bromo-2-deoxyuridine and direct R-banding fluorescence in situ hybridization.  相似文献   
1000.
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