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51.
52.
Nefazodone (2-[3-[4-(3-chlorophenyl)-1-piperazinyl]propyl]-5-ethyl- 2,4-dihydro-4-(2-phenoxyethyl)-3H-1,2,4-triazol-3-one) has been reported to be effective in the treatment of depression. Antagonism of serotonin type 2A (5HT2A) receptors, as well as inhibition of the serotonin (5HT) uptake carrier, has been suggested to contribute to the antidepressant action of nefazodone in vivo (Eison et al., 1990). Nefazodone weakly antagonized the quipazine-induced rise in rat serum corticosterone levels and the quipazine-induced increase in rat hypothalamic 3-methoxy-4-hydroxy-phenylglycol sulfate, suggesting blockade of 5HT2A receptors in vivo. Nefazodone, however, failed to antagonize the p-chloroamphetamine-induced depletion of mouse or rat brain 5HT, displaying a lack of effect on the 5HT uptake carrier. These data extend previous in vitro and in vivo data (Eison, et al. 1990) reporting nefazodone to be an antagonist at 5HT2A receptors, but fail to show inhibition of the 5HT uptake carrier in the same dose range. 相似文献
53.
R Kirchmair J Marksteiner J Troger SK Mahata M Mahata J Donnerer R Amann R Fischer-Colbrie H Winkler A Saria 《Canadian Metallurgical Quarterly》1994,6(5):861-868
Secretoneurin is a recently discovered neuropeptide derived from secretogranin II (SgII). Since this peptide could be detected in the dorsal horn of the spinal cord we studied whether it is localized in and released from primary afferent neurons. Secretoneurin was investigated with immunocytochemistry and radioimmunoassay in spinal cord, dorsal root ganglia and peripheral organs. SgII mRNA was determined in dorsal root ganglia. Normal rats and rats pre-treated neonatally with capsaicin to destroy selectively polymodal nociceptive (C-) fibres were used. Slices of dorsal spinal cord were perfused in vitro for release experiments. Immunocytochemistry showed a distinct distribution of secretoneurin-immunoreactivity (IR) in the spinal cord and, lower brainstem. A particularly high density of fibres was found in lamina I and outer lamina II of the caudal trigeminal nucleus and of the spinal cord. This distribution was qualitatively identical in rat and human post-mortem tissue. Numerous small diameter and some large dorsal root ganglia neurons were found to contain SgII mRNA. Capsaicin treatment led to a marked depletion of secretoneurin-IR in the substantia gelatinosa, but not in other immunopositive areas of the spinal cord and to a substantial loss of small (< 25 microns) SgII-mRNA-containing dorsal root ganglia neurons. Radioimmunoassay revealed a significant decrease of secretoneurin-IR in the dorsal spinal cord, the trachea, heart and urinary bladder of capsaicin-treated rats. Perfusion of spinal cord slices with capsaicin as well as with 60 mM potassium led to a release of secretoneurin-IR. In conclusion, secretoneurin is a neuropeptide which is stored in and released from capsaicin-sensitive, primary afferent (C-fibre) neurons.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
The fusion (F) protein of bovine respiratory syncytial virus (BRSV) was expressed by using a baculovirus vector. Antigenicity was tested by immunofluorescence analysis with F-specific monoclonal and polyclonal antibodies. Antibodies to recombinant F protein raised in a rabbit neutralized BRSV and human respiratory syncytial virus infectivity when tested in a plaque reduction assay. The recombinant F protein was evaluated as a source of antigen in an enzyme-linked immunosorbent assay (ELISA), and this ELISA was compared with the virus neutralization (VN) test for detecting BRSV antibodies in 10 consecutive serum samples from four calves vaccinated with a live modified BRSV vaccine and from two nonvaccinated control calves. The ELISA with the baculovirus-expressed F protein as an antigen compared favorably with the VN test and is a rapid, sensitive, and specific method for detecting serum antibodies to BRSV. 相似文献
55.
A new series of labdane-related diterpenes have been synthesized from (-)-sclareol and assayed in vitro cytotoxicity against mouse and human cancer cells. A key intermediate, homodrimane and furanolabdane derivatives show good in vitro cytotoxicity comparable to those of mitomycin C and adriamycin. 相似文献
56.
This paper calculates the mean duration of the postpartum amenorrhoea (PPA) and examines its demographic, and socioeconomic correlates in rural north India, using data collected through 'retrospective' (last but one child) as well as 'current status' (last child) reporting of the duration of PPA. The mean duration of PPA was higher in the current status than in the retrospective data; the difference being statistically significant. However, for the same mothers who gave PPA information in both the data sets, the difference in mean duration of PPA was not statistically significant. The correlates were identical in both the data sets. The current status data were more complete in terms of the coverage, and perhaps less distorted by reporting errors caused by recall lapse. A positive relationship of the mean duration of PPA was found with longer breast-feeding, higher parity and age of mother at the birth of the child, and the survival status of the child. An inverse relationship was found with higher education of a woman, higher education of her husband and higher socioeconomic status of her household, these variables possibly acting as proxies for women's better nutritional status. 相似文献
57.
58.
M Kumar R Prashad A Kumar R Sharma SK Acharya TK Chattopadhyay 《Canadian Metallurgical Quarterly》1998,45(24):2027-2032
Fifty consecutive patients with surgical obstructive jaundice were evaluated prospectively with ultrasonography (US), computed tomographic scans (CT scan) and cholangiography-percutaneous transhepatic cholangiography (PTC) or endoscopic retrograde cholangio-pancreaticography (ERCP). The diagnostic accuracy of ultrasound in defining the level of obstruction was 86% as compared to 86% and 94.8% for CT scan and cholangiography, respectively. To measure the etiology of the obstruction, the accuracy of ultrasound, CT scan and cholangiography were 84%, 86% and 75%, respectively. The sensitivity of CT scans and cholangiography in the diagnosis of choledocholithiasis was 100%, 81.8% and 90%, respectively, whereas specificity was 97%, 100% and 100%, respectively. Sensitivity for a diagnosis of malignant disease was 100% for both US and CT scans whereas specificity was 90% and 81%, respectively. Ultrasonography as a single radiological investigation is sufficient in the evaluation of the majority of patients with surgical obstructive jaundice. CT scan and cholangiography should be done only when US gives equivocal findings or if concomitant therapeutic procedures like basketing and stenting are also planned. 相似文献
59.
The effects of deprenyl on methamphetamine-induced dopamine depletions were studied in mice. Four SC injections of 12.5 mg/kg of methamphetamine at two-hour intervals caused substantial (72-82%) and long-lasting depletions of striatal dopamine. Pretreatment with either 25 or 40 mg/kg of deprenyl did not significantly alter the magnitude of this depletion. These results indicate that, unlike what is observed following MPTP, there is no protection afforded dopaminergic cells by deprenyl pretreatment in the methamphetamine model of parkinsonism. 相似文献
60.