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71.
Mielke H. Daniel W. Deicher H. Drommer W. Fischer M. Fritsch R. Mller-Vahl H. Sybrecht G. W. 《Clinical rheumatology》1987,6(2):26-34
Clinical Rheumatology - Rheumatoid arthritis (RA) as a systemic disease can attack many other organs in addition to the joints. A variety of pathological lesions of the blood vessels are... 相似文献
72.
Müllerian duct regression is first apparent in male pouch young of the tammar wallaby (Macropus eugenii) 6–7 days after birth and, as in eutherian mammals, is characterised by a condensation of the periductal mesenchyme into
a whorl around the ductal epithelial cells. A decrease in the density of the extracellular matrix was observed in the region
of the whorl. In contrast to eutherian mammals no changes were observed in the mean outer diameter of the Müllerian duct during
the early stages of regression. The time at which these mesenchymal changes occur corresponds to the period of Müllerian inhibiting
substance secretion in the postnatal tammar testis.
Accepted: 25 February 1997 相似文献
73.
Chretien Marie Francoise; Lebouvier Brigitte; Denis Alain; Chappard Daniel 《Human reproduction (Oxford, England)》1998,13(10):2767-2771
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments. 相似文献
74.
Marvin Rubenstein Robert Saffrin Michael Shaw Sergey Muchnik Patrick Guinan 《The Prostate》1995,27(3):148-153
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc. 相似文献
75.
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77.
Harold T. Kyriazi George E. Carvell Joshua C. Brumberg Daniel J. Simons 《Brain research》1996,712(2):325
Extracellular single-unit recordings were made in somatosensory cortical barrels of fentanyl-sedated rats. Whiskers were deflected singly or in paired combinations. lontophoretically-applied (−)-baclofen disproportionately reduced weak responses, and phaclofen disproportionately increased them, resulting in more tightly focused or more broadly focused receptive fields, respectively. Both drugs had only minor effects on surround inhibition. In light of previous findings, we conclude that GABAA and GABAB mechanisms both act to enhance spatial contrast, but that the former plays a much greater role in enhancing temporal resolution. 相似文献
78.
Summary The aim of this study was to investigate imipramine-induced alterations of cytochrome P-450 and to determine whether prolonged concomitant administration of imipramine and lithium results in a pharmacokinetic interaction.Male Wistar rats received imipramine (10 mg/kg i. p.) at 12 h intervals or lithium chloride (100 mg/kg in drinking water) or they were treated with the combination of these drugs for 2 weeks. The long term treatment with imipramine produced a very complex alteration of cytochrome P-450: imipramine increased the level of the cytochrome, but it decreased the rate of its own aromatic hydroxylation in position 2. The rate of N-demethylation in the side chain was not changed. Consequently, in the case of both hydroxylation and demethylation, calculated molecular activities were decreased to 48% and 70% respectively. This differential change in activities corresponded well to the observed decrease of absorption in difference spectra (type I) produced in microsomes by imipramine. Carbamazepine-induced type I difference spectra were also decreased by imipramine pretreatment, but to a lesser extent. In contrast, hexobarbital type I binding was increased by imipramine treatment while type II difference spectra produced by metyrapone were not affected. The preliminary SDS-PAGE analysis of cytochrome P-450 isoenzymes of control and imipramine treated rats showed that the investigated antidepressant markedly intensified a protein band at 50.11 kD while bands at 51.28 kD, 56.20 kD and 56.88 kD were less intensive. These results indicate that the alteration of cytochrome P-450 by imipramine treatment is not only of quantitative but also of qualitative character. Lithium alone given to rats affected neither the concentration of cytochrome P-450 in microsomal protein nor the rate of imipramine metabolism in vitro. Lithium given jointly with imipramine reduced imipramine-induced elevation of cytochrome P-450. This, however, did not cause any change in the rate of imipramine metabolism in vitro and accordingly in imipramine pharmacokinetics in vivo. The concentration of lithium in the blood plasma tended to increase by concurrent administration of imipramine.Send offprint requests to K. J. Netter at the above address 相似文献
79.
BACKGROUND: Telekid Care is a project that attempts to overcome the health and educational barriers faced by children in urban Kansas City, Kansas. Telemedicine units were placed in school nurses' offices and linked to physicians at the University of Kansas Medical Center (KUMC). This paper describes the development of this project, presents utilization data, and discuss the lessons learned from the application of telemedicine in a school setting. RESULTS: Project developers spent 11 months designing the protocol and procedures for a pilot test. Four elementary schools participated, and 187 consultations were conducted. The most common reason for consultation was ear, nose, and throat (ENT) problems, making up 28% of all consults. Mandatory school physical examinations and dermatology problems combined to make up an additional 40% of the consults. The average time that elapsed between the request for a consult and confirmation of an appointment was 23 minutes. When immediate service was requested, 85% of the consults occurred the day of the request. These results strongly demonstrate telemedicine's ability to offer immediate service to children in need. CONCLUSION: Telemedicine enabled underserved inner-city children to gain access to health services. This service was most effective when it was integrated into the delivery system. Furthermore, community groups strongly favored the project, positively influencing its acceptance as an innovative health care delivery system. 相似文献
80.
Daniel K. Howe Michael H. Vodkin Robert J. Novak Govinda Visvesvara G. L. McLaughlin 《Parasitology research》1997,83(4):345-348
Species-level identification of Acanthamoeba isolates is difficult and gives little or no indication of the isolate's pathogenicity. We identified two amplification-based genetic markers that were highly correlated with pathogenicity in Acanthamoeba spp. One marker, designed to amplify a 485-bp fragment of the small-subunit ribosomal RNA gene (ssrDNA), was preferentially amplified from the nonpathogenic strains; amplifications from the pathogenic strains yielded anomalous fragments of 650 and 900?bp. A second marker was developed on the basis of the anomalous 650-bp fragment. Primers to this sequence preferentially amplified a noncoding locus (called Ac6) only from the pathogenic strains. These two genetic markers may be useful for identification of pathogenic Acanthamoeba spp. strains. 相似文献