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The aim of this article is to provide clinicians and researchers a comprehensive overview of the development and functions of gesture in childhood and in select populations with developmental language impairments. Of significance is the growing body of evidence that gesture enhances, not hinders, language development. In both normal and impaired populations, gesture and language development parallel each other and share underlying symbolic abilities. Gesture serves several functions, including those of communication, compensation, and transition to spoken language. In clinical practice, gesture may play a valuable role in diagnosis, prognosis, goal selection, and intervention for children with language impairments. Where available, supporting evidence is presented. Needs for additional research on gesture are also highlighted.  相似文献   
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While two prophylactic HPV vaccines have been proven notably efficacious in clinical trials, the effectiveness of these vaccines at the population level remains to be evaluated. To lay the foundation for understanding the strengths and limitations of different endpoints for future effectiveness research, we present a comprehensive review of HPV-related clinical outcomes, including: (i) HPV type-specific positivity and persistence, (ii) Pap diagnoses (ASC-US, LSIL, and HSIL), (iii) histologic cervical cancer precursor lesions (i.e., CIN1, CIN2, and CIN3), (iv) invasive cervical cancer (ICC), (v) anogenital warts, (vi) recurrent respiratory papillomatosis (RRP), and (vii) other HPV-associated cancers (vulvar, vaginal, anal, penile, and oropharyngeal). While research on the vaccines’ effects on these HPV clinical outcomes in the general population is presently limited, numerous large trials will soon be completed, making a priori discussion of these potential outcomes especially urgent. Furthermore, population level systems to track HPV-associated clinical outcomes may need to be developed for HPV vaccine effectiveness evaluation.  相似文献   
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An oocentric view of folliculogenesis and embryogenesis   总被引:1,自引:0,他引:1  
The mammalian oocyte undertakes a highly complex journey to maturity during which it successively acquires a series of characteristics necessary for fertilization and the development of a healthy embryo. While the contribution of granulosa cells to oocyte development has been studied for many years, it has recently become apparent that the oocyte itself plays a key role in directing its own fate as well as the growth and differentiation of the follicle. This regulatory capacity is achieved through the synthesis and secretion of oocyte-specific factors, such as growth and differentiation factor 9 and bone morphogenetic protein 15, which act on granulosa cells to modify their proliferation, function and differentiation, as well as through direct physical contacts that occur at the granulosa cell-oocyte interface. This review describes key mechanisms by which the oocyte manipulates its own environment in order to achieve meiotic and developmental competence. The potential consequences of assisted reproductive technologies, such as in-vitro maturation and cryopreservation, on oocyte-granulosa cell interactions are also discussed, along with the impact of impaired oocyte development on early embryogenesis.  相似文献   
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OBJECTIVE: Type 2 diabetes mellitus is a well-known risk factor in patients with severe coronary artery disease undergoing coronary artery bypass grafting (CABG). The aim of the study was to analyze the endothelial dysfunction in these patients by evaluating postoperative soluble inflammatory cytokines. METHODS: Patients undergoing CABG without (n=15, group A) and with (n=14, group B) diabetes mellitus were analyzed for their release of E-selectin, interleukin-6 (IL-6), and tumor necrosis factor (TNF) up to 3 days postoperatively. A pharmacokinetic quantitative kinetic evaluation (Kinetica 2000) of maximum concentrations (c(max)), time to reach c(max) (t(max)), area under the curve (AUC(0-inf)), and terminal elimination half time (t(1/2)) was performed using a non-compartmental model. RESULTS: There was no difference in preoperative plasma concentrations of the cytokines and in the postoperative kinetic analyses of TNF when comparing both groups. However, the release of IL-6 was restricted with c(max) of 1055+/-543 pg/ml for group B versus 2112+/-1532 pg/ml for group A (p< or =0.05), paralleled by a decrease in the absolute amount (AUC(0-inf)) of IL-6. The t(1/2) remained unaffected (13.9+/-6.6h and 12.7+/-4.6h, respectively). The AUC(0-inf) of E-selectin decreased by a factor of 1.7 (p< or =0.05) with unchanged c(max) but reduced t(1/2) (12.9+/-10h for group B vs 33.1+/-20.4h for group A; p< or =0.01) referring to an augmented endothelial uptake and degradation of E-selectin. CONCLUSIONS: CABG with extracorporeal circulation could be used to verify a specific endothelial dysfunction in diabetic patients characterized by an impaired release of IL-6 and an increased turnover of E-selectin.  相似文献   
8.
The circulating concentration of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] is a physiologic index of enzymatic activity of the renal 1-hydroxylase of 25-hydroxychole-calciferol (25-OH-D3). Hydroxylation of 25-OH-D3 and circulating 1,25-(OH)2D3 are decreased in the streptozotocin diabetic rat. We previously found that activity of another redox enzyme system, cytosolic superoxide dismutase, also decreased in streptozotocin diabetes, can be restored by treatment with glutathione. In the present experiment we tested the effect of glutathione treatment on vitamin D metabolism in control and diabetic rats. Enteral glutathione increased circulating 1,25-(OH)2D3 and decreased 25-OH-D3 in both control and diabetic animals. These results suggest that exogenous glutathione increases 25-OH-D3 1-hydroxylation both under basal conditions in the normal animal and in diabetes-induced depression.  相似文献   
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Protoplasts of the pathogenic plant fungus, Crinipellis perniciosa, were transformed to hygromycin B resistance using the pAN7-1 plasmid, which contains the Escherichia coli hph gene under the control of Aspergillus nidulans regulatory sequences. The pAN7-1 plasmid was introduced by PEG/CaCl(2) treatment. Transformation frequencies of 1.6-2.5 transformants/microg of DNA were achieved. About 54% of the transformants were abortive and 40 analyzed transformants were mitotically stable and showed different hygromycin B resistance levels. The presence of the hph gene was checked by PCR in five transformants and the integration of multiple plasmid copies into different genome sites was observed by Southern analysis. This is the first report of a C. perniciosa transformation system and represents an important step for further research into genetic manipulation of this fungal plant pathogen.  相似文献   
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A/J and C57BL/6J mice behave differently in tests for alcohol preference, open-field activity, defecation in the open field, cricket attacking, and rope climbing. Chimeric mice, i.e., mice containing both A/J cells and C57BL/6J cells, were constructed and tested for these behaviors. Patterns of behavior among A/JC57BL/6J chimeras are such as to suggest that none of these behavior differences is controlled by a single cell or clone and that the same cell population that gives rise to the strain difference in alcohol preference also gives rise to the differences in open-field activity and defecation, while separate cell populations control cricket killing and rope climbing.This research was supported by Research Grants AA 00388 and HD 03015 to M. N. N. and MH 18996 to K. B. Computing assistance was obtained from the Health Sciences Computing Facility, UCLA, supported by NIH Special Research Resources Grant RR-3.  相似文献   
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