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991.
PURPOSE: Language acquisition is predictive of successful reading development, but the nature of this link is poorly understood. METHOD: A sample of 7,179 twin pairs was assessed on parent-report measures of syntax and vocabulary at ages 2, 3, and 4 years and on teacher assessments of reading achievement (RA) at ages 7, 9, and 10 years. These measures were used to construct latent factors of early language ability (LA) and RA in structural equation model-fitting analyses. RESULTS: The phenotypic correlation between LA and RA (r = .40) was primarily due to shared environmental influences that contribute to familial resemblance. These environmental influences on LA and RA overlapped substantially (rC = .62). Genetic influences made a significant but smaller contribution to the phenotypic correlation between LA and RA, and showed moderate overlap (rA = .36). There was also evidence for a direct causal influence of LA on RA. CONCLUSIONS: The association between early language and later reading is underpinned by common environmental and genetic influences. The effects of some risk factors on RA may be mediated by language. The results provide a foundation for more fine-grained studies that examine links between specific measures of language, reading, genes, and environments.  相似文献   
992.
993.
Two children with acute lymphoblastic leukaemia (ALL) taking daily 6-mercaptopurine as part of a national UK therapeutic trial repeatedly developed profound myelosuppression on 25% of the standard protocol dose. Both were found to have undetectable intracellular activity of thiopurine methyltransferase (TPMT), an enzyme controlling one of the major alternative catabolic pathways of 6-mercaptopurine, and both produced higher concentrations of cytotoxic drug metabolites at 10-25% of the protocol dose than other patients taking 100%. It is supposed that these patients represent the 0.33% of the normal population constitutionally lacking TPMT. It is important to recognise such individuals both to avoid fatal bone marrow failure through inadvertent overdosage, and to be reassured that an adequate drug effect can be achieved at around 10% of the standard dose.  相似文献   
994.
Purpose To evaluate the role of endometrial stromal cells and their secretory proteins in early embryo development, two-celled CB6F1 mouse embryos were cultured alone or cocultured with human endometrial stromal cells in various culture conditions.Results The percentage of embryo blastocyst formation, hatching, and outgrowth was significantly greater in (1) coculture with endometrial stromal cells than in a cell-free control when both coculture and control were carried out in protein-free medium or in RPMI 1640 plus 10% fetal calf serum; (2) coculture with hormone (i.e., progesterone plus relaxin)-treated cells than in coculture with hormone-nontreated cells; and (3) media supplemented with isolated endometrial secretory proteins than in media supplemented with BSA (0.35%). Embryo development was not found to be significantly different in coculture and in media supplemented with endometrial secretory protein.Conclusion Our data provides credence to the theory that endometrial stromal cells enhance embryo development by secreting specific proteins that are beneficial to embryo growth in vitro.Presented at the 48th Annual Meeting of the American Fertility Society, New Orleans, Louisiana, October 31–November 5, 1992.  相似文献   
995.
Purpose: Our purpose was to determine whether immature oocytes could be retrieved under local anesthesia, whether these oocytes would mature and fertilize in vitro, and whether adequate endometrium development could be obtained after hormonal supplementation. Methods: Ovum pick-up was performed under local anesthesia. Immature oocytes were cultured and inseminated. To prepare the endometrium, estradiolvalerate was administered in combination with micronized progesterone. Results: Immature oocytes were obtained in all cases. Fifty-six percent (n = 30) of the oocytes developed into metaphase II (MII) after 48 hr of culture, and another 20% reached the MII stage by 72 hr. Normal fertilization was observed in only 10% of oocytes inseminated. No embryonic development occurred, and therefore embryo transfer was not performed in any of the patients. Endometrial microbiopsy was performed in all subjects and endometrial development was considered sufficient in eight patients. Conclusions: We collected immature oocytes from patients with polycystic ovary syndrome without general anesthesia. In vitro maturation of these oocytes seemed adequate but fertilization rates were poor. Sufficient endometrial quality was obtained after hormonal substitution.  相似文献   
996.
Purpose: Caring for women with chronic pelvic pain (CPP) is challenging. There have been few studies on what factors patients consider to be important when being treated for their pelvic pain. This study sought to identify the key factors of the health care visit that contribute to patient’s overall satisfaction with their care in a CPP clinic.

Materials and methods: Between January 2015 and December 2016, new patients visiting a tertiary care CPP clinic were recruited to complete a patient satisfaction survey. Inductive thematic analysis was performed on response data regarding important factors that impact patient satisfaction with their visit/care.

Results: Five themes of patient satisfaction identified included: providers with a compassionate and caring attitude, being listened to, clear communication with collaboration when needed, quality time spent with patient, and having a plan of care with recommendations. The theme regarding provider’s compassion and listening skills was the most frequently identified. Pain relief was seldom mentioned as a source of patient satisfaction.

Conclusions: The data suggest that a focus on empathic communication may make a meaningful difference in meeting the needs of women with CPP as well as strengthening the provider/patient relationship.  相似文献   

997.
Biochemical and metabolic data have led to the conclusion that the enzyme phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32) contributes to a critical point of divergence in energy conservation pathways between mammals and nematodes. To facilitate the determination of the molecular basis for host vs parasite differences in PEPCK, we have cloned a cDNA encoding this enzyme from a parasitic nematode of ruminants, Haemonchus contortus. H. contortus PEPCK was cloned by functional complementation of a PEPCK, malic enzyme strain of Escherichia coli (E1786) using an egg stage H. contortus cDNA library in λZAPII. Selection was for growth on malate as the sole carbon source (malate phenotype). We isolated a plasmid, pPEPCK, which reproducibly confers a malate phenotype in E1786. The sequence of the 2.0-kb EcoRI insert of pPEPCK predicts a 612-amino acid protein which shows about 74% similarity to Drosophila melanogaster and chicken PEPCK. Extracts of E1786[pPEPCK], but not E1786, contain IDP- or GDP-dependent PEPCK enzyme activity. Sequence analysis revealed that the open reading frame (ORF) in pPEPCK lacked a 5′ initiation codon and was probably expressed as an in-frame fusion protein with β-galactosidase. A strategy combining library screening with PCR analysis of positive clones led to the identification of a clone encoding 6 additional NH2-terminal amino acids, including a Met, which, by comparison with known PEPCK amino acid sequences, is likely to be the translation initiation site.  相似文献   
998.
The sneeze reflex is a valuable tool for exploring the maturation of the respiratory control in the newborn as it alters both inspiratory and expiratory activities. Air puff stimulation of the superior nasal meatus innervated by ethmoidal afferents consistently evokes sneeze in adult cats. Such stimulation evokes only a reinforcement of expiratory activities in newborn kittens. This study demonstrates that the pattern of Fos-like immunoreactivity evoked by nasal stimulation changes during functional maturation of sneeze. Nasal stimulation evoked immunoreactivity (i) in the trigeminal sensory complex, at the levels where nasal afferents project, (ii) in the reticular formation, (iii) in the solitary complex and (iv) in the parabrachial area of mature kittens. The evoked immunoreactivity was the same in newborn kittens as in mature kittens in the projection areas of the nasal primary afferents. Fos response was less than half that in mature kittens in the reticular formation and absent in the solitary complex or the parabrachial area. Sneeze can be elicited from the time when evoked immunoreactivity in the solitary complex and the parabrachial area is above control levels. These data provide evidence that the maturation of sneeze is dependent on the development of central relays allowing peripheral inputs to be integrated by neurons engaged in respiratory control.  相似文献   
999.
We explored methods for kinship and linkage analysis in a Hutterite pedigree comprising 1,544 individuals, 72 of whom were diagnosed with asthma. Subpedigrees were selected by (a) identifying nuclear families containing asthmatics, (b) identifying couples with many asthmatic descendants in an ad hoc manner, and (c) finding the most recent common ancestors of all asthmatics. Markov chain Monte Carlo (MCMC) methods were used to estimate allele sharing in the larger subpedigrees and transmission/disequilibrium tests were performed on nuclear families. On chromosome 5q near the cytokine cluster, modest evidence for linkage to asthma was obtained. Using MCMC, we were able to evaluate the evidence for linkage in complex subpedigrees of several hundred individuals, and hence, incorporate some of the co‐ancestry of this founder population. © 2001 Wiley‐Liss, Inc.  相似文献   
1000.
 Approach responses, consummatory behaviors, and directed motor responses maintained by food reward resemble autoshaping CRs and are increased by lower doses of ethanol. This study evaluated the effects of presession IP injections of ethanol doses (0.00, 0.25, 0.50, 0.70, or 1.00 g/kg) on the acquisition of lever-press autoshaping CR performance in groups of male Long-Evans hooded rats. Paired groups received 15 daily sessions of Pavlovian autoshaping procedures, wherein the insertion of a retractable lever for 5 s (CS) was followed by the response-independent presentation of food (US). Ethanol facilitated lever-press autoshaping CR acquisition, as revealed by dose-related increases in the number of trials on which CRs were performed. The form of the dose-effect curve was inverted U-shaped with maximal responding induced during sessions 1–5 by the 0.70 g/kg ethanol dose. A similar dose-effect curve was observed during sessions 11–15, revealing that the effects of ethanol on autoshaping CR performance were relatively stable. A pseudoconditioning control group injected presession with 0.50 g/kg ethanol received training wherein the food US was presented randomly with respect to the lever CS. Few lever-presses were performed by the Random 0.50 group, indicating that ethanol’s effects on autoshaping CR acquisition and maintenance observed in the Paired 0.50 group were not due to its psychomotor activating effects. A non-injection control group performed more autoshaping CRs than did the control group injected presession with saline, indicating that daily presession IP injections per se suppress autoshaping CR performance. Results reveal that low doses of ethanol enhance Pavlovian conditioning of directed motor and consummatory-like responding maintained by food reward. Implications for autoshaping accounts of impulsivity and drug abuse are considered. Received: 15 December 1997 / Final version: 27 March 1998  相似文献   
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