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81.
MHC-G is a class Ib (non-classical) major histocompatibility complex (MHC) whose functional and evolutionary characteristics are still under scrutiny. The study of noncoding sequences in the MHC genes may provide important phylogenetic information. In this work we have sequenced the MHC-G exon 8, which encodes for the 3'UT region, in different species of primates. It has been shown that: (1) a previously described 14 base pair (bp) deletion polymorphism is human-specific and the HLA-G alleles may be classified according to its absence or presence; (2) another newly described 3 bp deletion/insertion polymorphism is also human-specific; and (3) another newly described 51 bp deletion polymorphism is common to Pongidae and humans, but is not found in other primates belonging to the Cercopithecinae family. A hypothesis on the evolutionary pathway of this gene is put forward in the light of these findings.  相似文献   
82.
83.
The aim of this study was to determine whether an intrapleural injection of barium sulphate would produce pleurodesis in rats. Additionally, respiratory mechanics and pleural remodelling were analysed. Single intrapleural injection of barium sulphate (100%) or saline was given to Wistar rats. Respiratory system, lung, and chest wall elastic, resistive and viscoelastic/inhomogeneous pressures were measured by the end-inflation occlusion method at 2 and 30 days after injection. The pleura were examined for gross and histopathological evidence of pleural inflammation and fibrosis, and the underlying lungs were also studied by morphometry. All pulmonary mechanical parameters increased at day 2, but were not different from control at 30 days after injection. Chest wall mechanical parameters did not change. Macroscopic evaluation demonstrated pleural adherence without haemothorax. Histopathologic analysis showed pleural inflammation and fibrosis. There was no alveolar inflammation or fibrosis in both groups. In conclusion, barium sulphate induced pleurodesis with either no changes in respiratory mechanics or lung lesion at day 30.  相似文献   
84.
This report describes a family with mental retardation in two brothers. The pedigree is consistent with either X-linked mental retardation or autosomal recessive inheritance. The clinical features consist of coarse face, prominent lower lip, large testes, and obesity. This same constellation of findings was observed in a family with X-linked mental retardation (XLMR) reported by Shashi et al. [2000: Am J Hum Genet 66:469-479]. Furthermore, haplotype analysis was consistent with localization of the Shashi XLMR syndrome in Xq26-q27. Thus, the family likely represents a second occurrence of the Shashi XLMR syndrome.  相似文献   
85.
As previously reported, unilateral pyramidotomy in newborn rats results in the development of an aberrant ipsilateral corticospinal tract that originates from the intact side. In the present study, limb preference after unilateral pyramidotomy in adult and neonatal rats was examined in search of differences that might correlate with this aberrant tract. However, no significant differences were observed between the two groups. Postoperatively, adult animals preferred the limb corresponding to the intact corticospinal tract in spite of a pre- and postoperative testing bias toward the opposite limb. Similarly, the animals that sustained neonatal lesion followed by testing at maturity also preferred the limb corresponding to the normal crossed corticospinal tract.  相似文献   
86.
AIM--To determine whether iron metabolism influences the incidence of systemic fungal infection in patients with haematological malignancies. METHODS--The study population comprised 74 patients who had undergone myeloablative chemotherapy. Systemic fungal infections were classified as confirmed (histological confirmation or characteristic septate hyphae) or possible (antibiotic resistant fever which resolved following administration of intravenous amphotericin B, together with either typical radiographic lesions or massive oropharyngeal candidiasis). Parameters of iron metabolism included serum iron concentrations, total iron binding capacity, serum transferrin, and ferritin concentrations and transferrin saturation values. RESULTS--Patients who developed a fungal infection had substantially increased transferrin saturation values and ferritin concentrations at diagnosis together with low serum transferrin and high serum iron concentrations. This profile was present in patients with a fungal infection regardless of the underlying haematological disorder. CONCLUSION--Increased transferrin saturation values and high ferritin concentrations may be additional risk factors for the development of systemic fungal infection in patients with haematological malignancies.  相似文献   
87.
88.
Candida albicans is an increasingly important fungal pathogen. Alveolar macrophages respond to fungal components such as zymosan by releasing arachidonic acid (AA) and AA metabolites. However, few studies hypothesized that macrophages respond to C. albicans by releasing AA and generating AA metabolites as a consequence of interaction of mannose and beta-glucan receptors with fungal cell wall components. [14C]AA-labeled rabbit alveolar macrophages released AA following stimulation with either live or heat-killed C. albicans. High-pressure liquid chromatography analysis revealed that 55% of the AA released was metabolized via cyclooxygenase and lipoxygenase pathways. The metabolites consisted of prostaglandin E2, prostaglandin F2 alpha, 6-ketoprostaglandin F1 alpha, thromboxane B2, and leukotrienes B4 and D4. We further examined the roles of alpha-mannan and beta-glucan components of C. albicans in mediating these alterations of eicosanoid metabolism. Prior work in our laboratory has shown that soluble alpha-mannan and beta-glucan inhibit macrophage mannose and beta-glucan receptors, respectively. Incubation of alveolar macrophages with soluble alpha-mannan derived from C. albicans (1 mg/ml) resulted in 49.8% +/- 2.6% inhibition of macrophage AA release during stimulation with intact C. albicans (P = 0.0001 versus control). Macrophage AA release in response to C. albicans was also inhibited to a significant but lesser degree by soluble beta-glucan (36.2% +/- 1.3%; P = 0.008 versus control). These results indicate that C. albicans stimulates macrophage AA metabolism and that these effects are partly mediated by alpha-mannan and beta-glucan constituents of the fungus.  相似文献   
89.
A comparative randomized trial was carried out on two intrauterine contraceptive devices: the Nova-T and the MLCu375. The IUDs were used by 1116 and 1237 women respectively, over a period of 2 years. The reasons for IUD removal were analyzed after one and two years using the life-table method. Statistically significant differences were found in the rates for pregnancy, expulsion and removal for bleeding and/or pain favoring the MLCu375 IUD.
Resumen Se hizo una prueba comparativa al azar de dos dispositivos anticonceptivos intrauterinos: el Nova-T y el MLCu375. Los DIU fueron usados por 1116 y 1237 mujeres respectivamente, durante un período de 2 años. Las razones para quitar un DIU fueron analizadas después de uno y dos años de uso empleando el método de tabla de vida. Se encontraron diferencias estadísticas significativas en las tasas de embarazo, expulsión y remoción por sangrado y/o dolor, siendo favorables para el MLCu375.

Resumé Une étude comparative randomisée a été effectuée sur deux dispositifs contraceptifs intrautérins: le Nova-T et le MLCu375. Ces stérilets ont été utilisés respectivement par 1116 et 1237 femmes sur une période de deux ans. On a analysé après un an et après duex ans, par la méthode des tables de survie, les raisons pour lesquelles ces DIU avaient été abandonnés. Des différences significatives du point de vue statistique ont été constatées dans les taux de grossesse, d'expulsion et de retrait pour cause de saignement et/ou de douleurs, et ces différences étaient favorables au dispositif MLCu375.
  相似文献   
90.
A comparative randomized trial was made of two intrauterine contraceptive devices: Nova-T and MLCu375. The IUDs were used by 637 and 606 women, respectively, for one year, unless the device was removed earlier. The reasons for IUD removal were analyzed after one year using the life-table method. Statistically significant differences were found in expulsion and removal for bleeding and/or pain rates.
Sumario Se hizo un estudio comparativo al azar de dos dispositivos anticonceptivos intrauterinos: el NOVA T y el MLCu375. Durante un año, a menos que el dispositivo hubiese sido quitado antes, los DIU fueron usados por 637 y 606 mujeres respectivamente. Las razones de la remoción de un DIU fueron analizadas después de un año usando el método de la tabla de vida. Se encontraron diferencias estadisticamente significativas en tasas de expulsión y de remoción por sangrado y/o dolor.

Resumé Une étude comparative randomisée a été effectuée sur deux dispositifs intrautérins contraceptifs: NOVA T et ML CU 375. Les DIU devaient être utilisés respectivement par 637 et 606 femmes, pendant une année, exception faite des cas où le stérilet a dû être retiré plus tôt. Les motifs du retrait ont été analysés une année plus tard grâce à la méthode des tables de survie. Les statistiques ont montré des différences significatives des taux d'expulsion et de retrait pour saignements ou douleurs.
  相似文献   
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