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S Biver S Scohy J Szpirer C Szpirer B André A-M Marini 《Transfusion Clinique et Biologique》2006,13(1-2):167-168
Ammonium excretion into urine is a major process essential to the regulation of acid-base homeostasis. We have shown that Rh-type proteins, including renal RhCG, belong to the Mep/Amt family of ammonium transporters and promote bi-directional ammonium transport upon heterologous expression in yeast. To study the physiological role of RhCG and to test a potential function in ammonium excretion, we have generated mice bearing an invalidation of the corresponding gene. 相似文献
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J-P Lefaucheur J-J Labat G Amarenco A-G Herbaut D Prat-Pradal J Benaim B Aranda M-C Arne-Bes V Bonniaud P-M Boohs K Charvier F Daemgen P Dumas J-P Galaup S Sheikh Ismael J Kerdraon P Lacroix D Lagauche E Lapeyre M Lefort A-M Leroi R-J Opsomer B Parratte J-G Prévinaire P Raibaut J-Y Salle M-C Scheiber-Nogueira J-M Soler M-F Testut C Thomas 《Clinical neurophysiology》2007,37(4):223-228
Entrapment of the pudendal nerve may be at the origin of chronic perineal pain. This syndrome must be diagnosed because this can result in the indication of surgical decompression of the entrapped nerve for pain relief. Electroneuromyographic (ENMG) investigation is often performed in this context, based on needle electromyography and the study of sacral reflex and pudendal nerve motor latencies. The limits of ENMG investigation, owing to various pathophysiological and technical considerations, should be known. The employed techniques do not assess directly the pathophysiological mechanisms of pain but rather correlate to structural alterations of the pudendal nerve (demyelination or axonal loss). In addition, only direct or reflex motor innervation is investigated, whereas sensory nerve conduction studies should be more sensitive to detect nerve compression. Finally, ENMG cannot differentiate entrapment from other causes of pudendal nerve lesion (stretch induced by surgical procedures, obstetrical damage, chronic constipation...). Thus, perineal ENMG has a limited sensitivity and specificity in the diagnosis of pudendal nerve entrapment syndrome and does not give direct information about pain mechanisms. Pudendal neuralgia related to nerve entrapment is mainly suspected on specific clinical features and perineal ENMG examination provides additional, but no definitive clues, for the diagnosis or the localization of the site of compression. In fact, the main value of ENMG is to assess objectively pudendal motor innervation when a surgical decompression is considered. Perineal ENMG might predict the outcome of surgery but is of no value for intraoperative monitoring. 相似文献
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This article presents normal EEG characteristics and their maturational pattern in premature infants of 24-30 weeks gestational age. Although the very premature infants with a normal outcome are not that numerous, their normal EEG pattern should be known, as EEG constitutes a basis for neurological prognosis. Background activity is first discontinuous but the discontinuity gradually decreases and the activity is completely continuous at 30 weeks of age, during active sleep. At the same time, interburst intervals become shorter so that the proportion of time without EEG activity decreases. Based on EEG activity and eyes movements, a rough sleep state differentiation appears as early as 25 weeks of gestational age and is complete at 30 weeks. The main EEG figures are high-voltage delta waves, whose frequency is slower and amplitude higher in younger infants. Temporal delta waves occur in sequences and are characteristic of the very premature infant; they progressively become smaller and less numerous and disappear around 27-28 weeks. In contrast, occipital delta waves remain numerous; they are of high voltage and usually bilaterally superimposed with fast rhythms. Both types of frontal delta waves that are seen in 24-27 weeks premature babies disappear with maturation. Bursts of synchronized delta waves, which are less numerous than localized delta waves, also disappear before 28 weeks of gestational age. Finally, diffuse theta bursts which are mainly recorded at 26-27 weeks, progressively focus on temporal areas with maturation. At 30 weeks, they are observed on temporal areas, mainly during slow-wave sleep. 相似文献
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R. Kalra A-M. Jones J. Kirk G. E. Adams I. J. Stratford 《International journal of cancer. Journal international du cancer》1993,54(4):650-655
Prolonged hypoxia induced transient drug resistance in Chinese hamster lung fibroblasts. Previously hypoxic cells were resistant to adriamycin and resistant to etoposide. Complete recovery of etoposide sensitivity was observed following re-aeration for 24 hr. A change in P-glycoprotein expression was unlikely to contribute to the resistance caused by hypoxia, since adriamycin resistance was not reversed by verapamil. However, alteration in the plasma membrane structure may be involved, since previously hypoxic cells were resistant to extracellular superoxide radical generated by the addition of xanthine/ xanthine oxidase. In contrast, adriamycin sensitivity was not altered by hypoxia in 3 human breast-cancer cell lines. MDA-468 and MCF-7/Adr differed in their response to EGF, independent of the presence of hypoxia. These results suggest that hypoxic-stress-induced drug resistance is not generalized. 相似文献
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F. Scheutz M.I.N. Mates L. Andsager A-M. Holm J. Moshi C. Kagoma N. Mpemba 《Journal of clinical periodontology》1997,24(8):580-587
Abstract Individuals in Tanzania who have limited access to medical and dental treatment provide an opportunity to study the natural association between periodontal condition and HIV infection and the stage of infection. 119 HIV infected adult individuals and 73 individuals with AIDS from the AIDS Clinical Trial Clinic at Muhimbili Medical Centre (MMC) in DaresSalaam participated as cases. Mean age was 35.3 and 35.1 years, respectively. 156 individuals with a mean age of 28.3 years, confirmed as HIV seronegative, served as controls. There were no significant differences in bleeding on probing, pocket formation or attachment loss among the HIV seronegative individuals. HIV seropositive and AIDS patients. We applied multiple logistic regression to calculate odds ratios for presence of periodontal conditions adjusting for age, gender and DMFT. Our odds ratios did not reveal any significant associations between bleeding on probing, pocket formation or attachment loss with regard to lymphocyte and CD4+ T cell counts among the HIV infected individuals and AIDS patients. When associations were investigated with regard to HIV serostatus (HIV seronegative. HIV seropositive or AIDS), our adjusted odds ratios were insignificant, too. In fact, most odds ratios were close to 1. Thus, our study supports recent views that the presence, extent and severity of periodontal disease among HIV infected individuals, may be less that hitherto thought. 相似文献
10.
van Dongen YC Deniau JM Pennartz CM Galis-de Graaf Y Voorn P Thierry AM Groenewegen HJ 《Neuroscience》2005,136(4):1049-1071
The nucleus accumbens is thought to subserve different aspects of adaptive and emotional behaviors. The anatomical substrates for such actions are multiple, parallel ventral striatopallidal output circuits originating in the nucleus accumbens shell and core subregions. Several indirect ways of interaction between the two subregions and their associated circuitry have been proposed, in particular through striato-pallido-thalamic and dopaminergic pathways. In this study, using anterograde neuroanatomical tracing with Phaseolus vulgaris-leucoagglutinin and biotinylated dextran amine as well as single-cell juxtacellular filling with neurobiotin, we investigated the intra-accumbens distribution of local axon collaterals for the identification of possible direct connections between the shell and core subregions. Our results show widespread intra-accumbens projection patterns, including reciprocal projections between specific parts of the shell and core. However, fibers originating in the core reach more distant areas of the shell, including the rostral pole (i.e. the calbindin-poor part of the shell anterior to the core) and striatal parts of the olfactory tubercle, than those arising in the shell and projecting to the core. The latter projections are more restricted to the border region between the shell and core. The density of the fiber labeling within both the shell and core was very similar. Moreover, specific intrinsic projections within shell and core were identified, including a relatively strong projection from the rostral pole to the rostral shell, reciprocal projections between the rostral and caudal shell, as well as projections within the core that have a caudal-to-rostral predominance. The results of the juxtacellular filling experiments show that medium-sized spiny projection neurons and medium-sized aspiny neurons (most likely fast-spiking) contribute to these intra-accumbens projections. While such neurons are GABAergic, the intrastriatal projection patterns indicate the existence of lateral inhibitory interactions within, as well as between, shell and core subregions of the nucleus accumbens. 相似文献