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排序方式: 共有327条查询结果,搜索用时 15 毫秒
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W A Shearman 《BMJ (Clinical research ed.)》1984,288(6431):1691-1692
3.
Differential expression of multiple protein kinase C subspecies in rat central nervous tissue 总被引:16,自引:0,他引:16
M S Shearman Z Naor U Kikkawa Y Nishizuka 《Biochemical and biophysical research communications》1987,147(3):911-919
Protein kinase C from a number of areas of rat central nervous tissue was resolved into three distinct fractions upon hydroxyapatite column chromatography. One of the enzyme fractions, designated type II, could be further distinguished into two subspecies with polyclonal antisera, which were raised against synthetic peptides specific for the predicted amino acid sequences of two alternative cDNA clones encoding this enzyme type. Using a combination of these biochemical and immunological techniques, the relative activity of the multiple subspecies of protein kinase C was assessed for each brain area. A distinct regional pattern of expression was found, which per se may be an important factor in determining the response of different neuronal cell types to extracellular stimuli. 相似文献
4.
The heterogeneity and differential expression of protein kinase C in nervous tissues 总被引:1,自引:0,他引:1
5.
The in vitro activity of several new imidazoles, cloconazole, sulconazole, butoconazole, isoconazole and fenticonazole, were compared with those of amphothericin B, flucytosine, and three azoles: econazole, miconazole and ketoconazole against isolates of pathogenic Candida. A total of 186 clinical isolates of 10 species of the genus Candida and two culture collection strains were tested by an agar-dilution technique. Isoconazole was the most active azole, followed by butoconazole and sulconazole. Differences between some of the species in their susceptibility to the antifungal agents were noted. Sulconazole and cloconazole had the highest activity in vitro against 106 isolates of C. albicans. Butoconazole and isoconazole were also very active against isolates of C. albicans, and were the most active azole compounds against 80 isolates of Candida spp. 相似文献
6.
Fentanyl (FEN) and diprenorphine's (DIPR) potentials for analgesia and reinforcement were assayed using rats. Analgesia was measured by the classic tail-flick test. The test germane to opioid reinforcement involved measuring pressing rates for direct electrical stimulation of the lateral hypothalamus and ventral tegmental area. FEN, as does morphine and heroin, produced strong analgesia and enhanced pressing rates for brain stimulation. DIPR produced no analgesia and antagonized FEN's analgesia. DIPR, at doses antagonizing FEN's analgesia, enhanced pressing for brain stimulation. DIPR's enhancement of pressing was antagonized by naloxone (100 micrograms/kg). When FEN and DIPR were given concurrently, pressing for brain stimulation was not reduced and was greater than after FEN alone was given. These data support a conclusion that different types of receptors are associated with opioid analgesia and reinforcement. 相似文献
7.
This study examines the role of PGF2a (prostaglandin F2alpha) in increasing the secretion rate of human prolactin. 11 women (mean gestational period, 18 weeks) seeking pregnancy termination were divided into 4 groups: 1) Group 1 consisted of 6 women who received 30 mg initially of PGF2a injected intramuscularly and an additional 15 mg after 24 hours if abortion had not occured; mean induction to termination period was 38 hours; 2) Group 2 comprised of 3 women who received PGF2a (500-1500 ug) via the transcervical route at 1 to 2 hourly interval; average number of injections was 20; mean induction to termination period, 24 hours; 3) Group 3 had 2 women receiving hypertonic saline by intraamniotic injection; mean induction to termination period was 51 hours; 4) Group 4 had 4 women who served as controls; mean observation period, 20 hours. Venous blood samples were heparinized in tubes at intervals of 2 to 3 hours. A homologous radioimmunoassay using highly purified human prolactin (for iodination and standards) plus rabbit antihuman prolactin measured serum prolactin. Spikes of serum prolactin up to 550 ng/ml were observed at irregular intervals in 5 women in Group 1; the spikes were less frequent and of smaller amplitude in Groups 3 and 4. The increase in serum prolactin was dramatic and more sustained in Group 2 patients and peaked towards the end of the prostaglandin infusion. Serum prolactin of Group 2 patients were significantly higher than those of Groups 3 and 4 (p0.01). 5 of 9 women whose pregnancies were terminated by PGF2a lactated. However, there was no significant difference between the mean serum prolactin levels in women who lactated (136 ng/ml) and those who did not (120 ng/ml). Although PGF2a is not a lactogenic hormone, this study shows that PGF2a stimulates the secretion of human prolactin during second trimester pregnancy. The fact that the transcervical route caused a significant increase in serum prolactin and the intraamniotic route did not is attributed to the increased systemic absorption of PGF2a following transcervical administration. No correlation was seen between the presence or absence of lactation and the serum prolactin level following pregnancy termination with PGF2a. 相似文献
8.
A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)). 相似文献
9.
The Lactococcus lactis sex-factor aggregation gene cluA 总被引:4,自引:0,他引:4
Jean-Jacques Godon Karen Jury Claire A. Shearman Michael J. Gasson 《Molecular microbiology》1994,12(4):655-663
A gene, cluA, was cloned from the chromosomally located sex factor of Lactococcus lactis MG1363. Sequence analysis revealed significant homology with previously described aggregation proteins in Enterococcus and Streptococcus species. The possibility that cluA was an equivalent protein involved in cell aggregation between donor and recipient bacteria during lactococcal conjugation was confirmed by its expression under the control of a heterologous promoter in L. lactis. Analysis of the homology between the CluA protein and the related proteins of Enterococcus and Streptococcus allowed a common structure for these proteins to be postulated. This consisted of five domains. Functionally conserved domains I and V act respectively as a secretary leader and C-terminal membrane anchor. Domains II and IV are conserved at the amino acid level and probably have common structural roles whereas domain III is variable and may control binding specificity. 相似文献