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排序方式: 共有7207条查询结果,搜索用时 15 毫秒
51.
Y. Fukuda Yoshihisa Fukuta Raita Higashino Masayuki Ogishima Kenji Yoshida Hajime Tamaki Mineo Takei 《Naunyn-Schmiedeberg's archives of pharmacology》1999,359(6):433-438
The effects of Z-350, (S)-4-[3-(4-{1-(4-methylphenyl)-3-[4-(2-methoxyphenyl)piperazine-1-yl]propoxy} benzoyl)indole-1-yl]butyric
acid hydrochloride, a newly synthesized compound possessing α1-adrenoceptor antagonistic and steroid 5α-reductase inhibitory actions, were studied in vitro. In functional experiments,
Z-350 shifted the concentration/response curve for the phenylephrine-induced contraction of rabbit prostate, urethra and aorta
to the right with pA2 values of 8.04, 7.57 and 7.13, respectively. The binding affinity of Z-350 for α1-adrenoceptors in rabbit prostate, urethra and aorta were estimated by the displacement of [3H]prazosin. The pK
i values for this action of Z-350 were 7.53, 7.95 and 7.62 for the prostate, urethra and aorta, respectively. α1-Adrenoceptor subtype selectivities were studied in the submaxillary gland (α1A) and liver (α1B) of rat. Z-350 inhibited the specific binding of [3H]prazosin to α1A and α1B-adrenoceptors with pK
i values of 7.82 and 7.29, respectively. Z-350 inhibited rat prostatic steroid 5α-reductase non-competitively with a pIC50 of 8.42. These results indicate that Z-350 is a α1-adrenoceptor antagonist and is a steroid 5α-reductase inhibitor. It is expected that Z-350 will be a candidate drug for the
treatment of benign prostatic hyperplasia.
Received: 26 January 1999 / Accepted: 2 March 1999 相似文献
52.
M Kamberi N Hajime P Kamberi N Uemura K Nakamura S Nakano 《Therapeutic drug monitoring》1999,21(3):335-340
A specific and sensitive reversed-phase high-performance liquid chromatographic (HPLC) method has been developed and validated for the simultaneous determination of grepafloxacin, ciprofloxacin, and theophylline in human plasma and urine. This assay allows these drugs to elute and be resolved in a single chromatogram at 280 nm, using a linear gradient. The procedure involves liquid-liquid extraction. Separation was achieved on a C18 reversed-phase column. The quantification limits were 0.05 mg/L in plasma and 0.5 mg/L in urine for grepafloxacin and ciprofloxacin and 0.5 mg/L in plasma and urine for theophylline. Standard curves were linear (correlation coefficients >0.999) over the ranges 0.05 to 5 mg/L for grepafloxacin and ciprofloxacin in plasma, from 0.5 to 20 mg/L for theophylline in plasma, and from 0.5 to 500 mg/L for the three drugs in urine. The coefficients of variation for the three drugs were less than 10% for within- and between-day analyses. The recoveries averaged 94.5% for theophylline, 93% for ciprofloxacin, 93.7% for grepafloxacin, and 95.1% for the internal standard (IS). The assay can be used for pharmacokinetic studies of these drugs, to investigate the interaction of grepafloxacin and ciprofloxacin with theophylline, or for routine simultaneous monitoring of theophylline, grepafloxacin, and ciprofloxacin. 相似文献
53.
The ultrastructure of parapapillary chorioretinal atrophy in eyes with secondary angle closure glaucoma 总被引:4,自引:0,他引:4
Toshiaki Kubota Ursula M. Schlötzer-Schrehardt Gottfried O. H. Naumann Toshihiko Kohno Hajime Inomata 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(6):351-358
Background: The present study was performed to investigate the ultrastructure of deep retinal layers and choroid corresponding to the parapapillary chorioretinal atrophy in eyes with secondary angle-closure glaucoma. Methods: The glaucomatous eyes included two eyes enucleated due to iris ring melanoma with high intraocular pressure and one eye with neovascular glaucoma enucleated due to ocular pain. The control eyes included one eye enucleated due to choroidal malignant melanoma with normal intraocular pressure and one eye enucleated during surgery for supramandibular carcinoma. These eyes were studied with light and electron microscopy. Results: In the region of parapapillary chorioretinal atrophy of glaucomatous eyes, the retinal pigment epithelial cells showed degenerative changes, such as loss of basal in foldings and microvilli, degenerated mitochondria, vacuolar degeneration and irregular distribution of melanin granules. The photoreceptors were decreased in number in this area of glaucomatous eyes. The lumen of the choriocapillary vessels adjacent to the optic nerve was collapsed. Conclusion: These results elucidate the fine structures of deep retina and choroid in the region of parapapillary chorioretinal atrophy of glaucomatous eyes, and suggest that the reduced choroidal perfusion might be the pathogenetic mechanism of glaucomatous parapapillary chorioretinal atrophy. 相似文献
54.
Kouichirou Nishiyama Hajime Hirose Yoshiaki Iguchi Kazuhiro Yamamoto Takashi Masaki Takahiro Kamijo Takeshi Ino Jun Yamanaka Kazuo Yao Makito Okamoto 《Nihon Jibiinkoka Gakkai kaiho》2003,106(3):220-225
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases. 相似文献
55.
56.
We describe a rare case of medulloblastoma in an adult woman with histological findings suggesting an origin for this neoplasm
in the external granular layer or its remnants. The patient presented with cerebellar dysfunction, and neuroimaging revealed
a right cerebellar mass lesion. Pathological examination of the operative specimen revealed a medulloblastoma with occasional
areas of neuronal or glial differentiation. Zic protein was also detected immunohistochemically in the tumor cells. The tumor
cells were mainly distributed in the subarachnoid space and extended to the cerebellar parenchyma through the perivascular
space to form tumor nodules. A suggestive finding, as concerns the origin of this neoplasm, was that the tumor cells were
also spread evenly along the subpial zone of the molecular layer, reminiscent of the cellular architecture of the fetal external
granular layer. 相似文献
57.
58.
Junko Miyamoto Hiroshi Asanuma Hideo Nakai Tomonobu Hasegawa Hajime Nawata Yukihiro Hasegawa 《Clinical Pediatric Endocrinology》2006,15(4):151-162
The prevalence of abnormalities in androgen receptor gene (AR) among patients with
ambiguous genitalia is unknown. Moreover, endocrinological data from prepubertal patients
with AR mutation are very limited. Thus, the aim of this study was to examine the
prevalence of abnormalities in AR among patients with both ambiguous genitalia, which was
defined as a combination of two or more genital abnormalities (i.e. hypospadias,
microphallus (penile length < 25 mm), hypoplastic scrotum, bifid scrotum, undescended
testis) in this study, and normal to elevated T levels. We also compared the
endocrinological data of prepubertal patients with AR mutation and ambiguous genitalia
with that of those without the AR mutation. We screened 26 Japanese prepubertal 46,XY
patients (five from three families were included) with both ambiguous genitalia and normal
to elevated T levels. Mutations in AR were found in three (two of the three were related).
Among the 23 patients without mutation in AR, the steroid 5-alpha-reductase 2 gene
(SRD5A2) was also examined in eight patients with elevated T/dehydrotestosterone ratio
after the hCG (>10) or with undervirilized family members. No mutation in SRD5A2 was
found. Characteristics of the three patients with mutation in AR were compared with the 23
patients without mutation. In two patients, basal T levels (0.3, 0.2 ng/ml) and peak T
levels after the hCG tests (8.3, 8.5 ng/ml) tended to be higher, and the peak LH/ peak FSH
ratios after the GnRH tests (4.6, 4.0) were higher than in patients without mutation, at
the ages of 1 yr and 9 mo and 3 yr and 8 mo, respectively. In conclusion, an abnormality
in either AR or SRD5A2 was not common among patients with ambiguous genitalia and normal
testosterone secretion. Elevated peak LH/peak FSH ratio (≥4) after the GnRH test in
addition to detectable basal T levels and elevated peak T levels after the hCG test may
infer AR abnormality in prepubertal patients with ambiguous genitalia at the age of one
and over, although further study is needed, because our data were limited. 相似文献
59.
Ohno Ken; Araki Naohiro; Yanase Toshihiko; Nawata Hajime; Iida Mitsuru 《Toxicological sciences》2005,83(2):406
The following sentences should have read: Results, Reproducibility 相似文献
60.