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1.
In the past few years, increased knowledge of the nature of transport proteins and their molecular regulation in the translocation of ions across kidney membranes has emerged. We are beginning to better understand the characteristics of the interaction of diuretics with these transport proteins. It is likely that this knowledge will permit further insight into nephron function regulation. 相似文献
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The morphological changes produced in the thyroid glands of albino rats following radiation with a 904 nm infrared laser were studied. Two different levels of radiation were applied: 46.8 J/cm2 and 140.4 J/cm2. Evaluation of the changes in the densities of the epithelial, colloidal and follicular volumes and of the activation index revealed that the laser beam produced changes in the thyroid parenchyma. It was observed that there was a direct relationship between the severity of the lesion and the radiation energy applied. 相似文献
4.
Alicia Gómez-Barrio David Montero-Pereira Juan J. Nogal-Ruiz José A. Escario Susana Muelas-Serrano Vladimir V. Kouznetsov Leonor Y. Vargas Méndez Juan M. Urbina Gonzáles Carmen Ochoa 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(1):73-78
A study of some antiparasitic properties of several homoallylamines and related tetrahydroquinolines and quinolines, previously
described, was carried out using in vitro activity assays against the epimastigote form of Trypanosoma cruzi and against Trichomonas vaginalis. Unspecific cytotoxicity against murine macrophages was also studied. Although the antichagasic and trichomonacidal activities
are not comparable to those of the standard drugs, nifurtimox and metronidazole, some of the compounds exhibit an interesting
specific antiparasitic activity. 相似文献
5.
Bradykinin-induced vasoconstriction of rat mesenteric arteries precontracted with noradrenaline. 总被引:4,自引:4,他引:0 下载免费PDF全文
1. Administration of bradykinin caused dose-dependent vasoconstriction in rat isolated perfused mesenteric arteries precontracted with noradrenaline. 2. The vasoconstrictor response was not mediated by BK1-bradykinin receptors. 3. Inhibition of cyclo-oxygenase with indomethacin, aspirin or meclofenamate abolished the vasoconstrictor effect of bradykinin, showing that a member of the arachidonic acid cascade may be involved. 4. Inhibitors of thromboxane synthesis (imidazole and UK 38485) did not affect or only reduced the bradykinin-induced vasoconstriction. 5. The endoperoxide H2/thromboxane A2 receptor antagonist SQ 29548 significantly reduced the vasoconstrictor effect of bradykinin, but did not affect the vasoconstrictor response to noradrenaline, adrenaline, vasopressin, 5-hydroxytryptamine or prostaglandins. 6. The eicosanoid(s) that mediate bradykinin-induced vasoconstriction appear to be synthesized outside the arterial endothelium. 7. The data suggest that the vasoconstrictor effect of bradykinin in the rat isolated mesenteric artery is mediated by vasoconstrictor arachidonic acid metabolites including the cyclic endoperoxides and/or the thromboxanes. 相似文献
6.
CONTEXT: The limited information available on the oral health status of rural children in the United States makes it difficult to devise policy strategies to address perceived problems. PURPOSE: To document the oral health status and dental care utilization of US children by place of residence, METHODS: Data from National Health Interview Surveys for 1995, 1997, and 1998, and from the third National Health and Nutrition Examination Survey (1988-1994) were analyzed. FINDINGS: Children residing in rural areas were more likely to be uninsured for dental care than were children from urban areas (41.1% versus 34.7%). A greater percentage of rural than urban children reported unmet dental needs (7.5% versus 5.6%); there was no difference in self-reported poor dental status. Urban children were more likely than rural children to have visited the dentist in the past year (73.6% versus 69.9%) and were also more likely to be regular users of dental care (61.7% versus 51.4%). Differences in percentage of rural and urban children with caries lesions and caries experience were not significant. CONCLUSIONS: Children residing in rural areas have less access to and utilization of dental care compared to children residing in urban areas. Moreover, poor rural children display less utilization of dental services than poor urban children. Differences in the sum of decayed and filled primary teeth and the sum of decayed, missing, and filled permanent teeth were not significant. 相似文献
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Fernando Regla Vargas Jos Carlos Cabral de Almeida Juan Clinton Llerena Dimas Fagundes Reis 《American journal of medical genetics. Part A》1992,44(6):716-719
We report on a boy with severe radial hypoplasia, absent thumbs and patellae, short stature, persistent diarrhea, slender nose and normal intelligence as another example of the RAPADILINO syndrome. © 1992 Wiley-Liss, Inc. 相似文献
9.
A Nuvole P Sanna G Paglietti C Juliano S Zanetti P Cappuccinelli 《Il Farmaco; edizione pratica》1989,44(6):619-632
Some 6-ethyl-1(2)(3)-R-1(2)(3)H-triazolo[4,5-f]quinolin-9-one-8-carboxy lic acids were prepared as novel analogues of oxolinic acid in order to evaluate the effect on antibacterial activity of the isosteric replacement of the dioxolic moiety with the triazole ring substituted in position 1 or 2. In vitro tests showed a good and selective activity against Escherichia coli (MIC 12.5 micrograms/ml) of compound (XVI). 相似文献
10.
We have determined a critical period for vestibular development in zebrafish by using a bioreactor designed by NASA to simulate microgravity for cells in culture. A critical period is defined as the briefest period of time during development when stimulus deprivation results in long lasting or permanent sensory deficits. Zebrafish eggs were collected within 3 hours of being laid and fertilized. In experiment 1, eggs were placed in the bioreactor at 3, 24, 30, 36, 48, or 72 hours postfertilization (hPF) and maintained in the bioreactor until 96 hPF. In experiment 2, eggs were placed in the bioreactor immediately after they were collected and maintained in the bioreactor until 24, 36, 48, 60, 66, 72, or 96 hPF. Beginning at 96 hPF, all larvae had their vestibulo-ocular reflexes (VOR) evaluated once each day for 5 days. Only larvae that hatched from eggs that were placed in the bioreactor before 30 hPF in experiment 1 or removed from the bioreactor later than 66 hPF in experiment 2 had VOR deficits that persisted for at least 5 days. These data suggest a critical period for vestibular development in the zebrafish that begins before 30 hPF and ends after 66 hPF. To confirm this, zebrafish eggs were placed in the bioreactor at 24 hPF and removed at 72 hPF. VORs were evaluated in these larvae once each day for 5 days beginning at 96 hPF. These larvae had VOR deficits that persisted for at least 5 days. In addition, larvae that had been maintained in the bioreactor from 24 to 66 hPF or from 30 to 72 hPF, had only temporary VOR deficits. In a final experiment, zebrafish eggs were placed in the bioreactor at 3 hPF and removed at 96 hPF but the bioreactor was turned off from 24 hPF to 72 hPF. These larvae had normal VORs when they were removed from the bioreactor at 96 hPF. Taken as a whole, these data support the idea that there is a critical period for functional maturation of the zebrafish vestibular system. The developmental period identified includes the timeframe during which the vestibular primary afferent neurons are born, innervate their central and peripheral targets, and remodel their central projections. 相似文献