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991.
Explores the problems and opportunities for professions allied to medicine (PAMS) in the new NHS internal market. Uses a mechanism from IT, namely outsourcing, to provide a new organizational model for the effective delivery of care by this group of professionals who are marginalized by the new role of the doctor as manager.  相似文献   
992.
The story of child and youth care is existential (Baizerman, 1992), developmental (Maier, 1987), and experiential (Fewster, 1990). It takes place in the here and now as workers weave care, learning, and counseling into daily interactions. At the foundation of these interactions is a series of moments of rhythm, presence, meaning, and atmosphere.  相似文献   
993.
PURPOSE: The goal of the present article is to provide information useful to clinical caseworkers and mental health professionals on the nature and correlates of psychological distress as well as high­risk factors related to the adaptation of mothers of Vietnamese Amerasians (MVAs) in the United States. METHODOLOGY: By using a series of psychological distress instruments, the psychological distress levels of MVAs were compared to that of Amerasian adolescents. PRINCIPAL FINDINGS: The data enabled us to identify possible high­risk factors related to the adaptation and adjustment of MVAs in the United States. The MVAs as a group were experienceing about equal levels of distress as the Amerasian adolescents. However, differences began to emerge when we used the clinical cutoff method and found that there were differences between the two groups in two of the measures. The MVAs had a significantly higher proportion who were in the clinical range as compared to the Amerasian adolescent group. The conditions that were found to put the MVAs at higher risk for psychological distress include: Feeling distant from Amerasian child, feeling close to Vietnamese child, having no relatives in the United States, higher number of years of schooling, lower income, higher number of times with serious illness, missing work due to serious illness, higher number of months at the resettlement camp, greater amount of knowledge about American husband, not being officially married to American husband, and lack of support from American husband. CONCLUSIONS: The psychological instruments used in this study were not refined enough to be used for diagnosis of specific psychological disorders. Differences between Amerasian adolescents and MVAs pointed out the importance of examining both the groups' level of distress and the propotions in each grouop who were experiencing clinical levels of distress. The high risk factors identified in the current study may be used to examine potential sources of psychological distress for MVAs. RELEVANCE TO ASIAN AMERICAN AND PACIFIC ISLANDER POPULATIONS: This article is particularly relevant to Vietnamese and Amerasian. KEY WORDS: Psychological distress, high risk factors, MVAs, Ameriasian adolescents.  相似文献   
994.
Purpose To evaluate biochemically and clinically a new formulation of modified Ham's F-10 medium made without the inclusion of hypoxanthine. The medium was formulated for long-term storage and use by separately preparing a stable liquid (basal) portion and a freeze-dried supplement containing the labile medium components.Results Following 18 months of storage the basal medium was biochemically analyzed for its amino acid (aa's) and vitamin content. Cysteine and tryptophan were decreased to less than 30% of their starting theoretical concentrations (STCs). Asparagine, serine, tyrosine, histidine and lysine were present at 50% to 70% of their STC. The remaining aa's were all within 90% of their STCs except arginine which was at 77%. All of the vitamins were present at 90% or more of their STCs except inositol, riboflavin and'thiamine which were present at 70% of their STCs. IVF with the new formulation resulted in 13 deliveries from 51 aspirations (25%) as compared with 10/39 (26%) in 1991, when standard medium preparation was used. Oocyte donation resulted in 30 deliveries from 84 cycles (36%) with the new formulation as compared with 21/65 (32%) in 1991.Conclusions (1) The new basal with lyophilized supplement formulation produces similar clinical results in the IVF laboratory as medium prepared in the standard fashion, (2) certain amino acids and vitamins are not stable in the liquid basal medium, and (3) the separate formulation of a liquid basal medium with lyophilized supplement is convenient, viable alternative to modified Ham's F-10 medium prepared in the standard manner (i.e., from powder) and may decrease the need for frequent medium preparation.Modified Ham's F-10 Medium, Irvine Scientific, Santa Ana, California.Presented at the 42nd Annual Meeting of the Pacific Coast Fertility Society, Indian Wells, California, April 20–24, 1994.  相似文献   
995.
Background: Transferrin and Fe concentrations increase in the intraocular fluids in pathological conditions and the lens accumulates Fe during ocular inflammation. Tissues take up Fe from transferrin by two mechanisms, receptor-medicated endocytosis of diferric transferrin and a process occurring at the cell membrane which may be mediated by an oxido-reductase. However, Fe metabolism, transport and storage have not been previously investigated in the lens. This study was designed to characterize the uptake of Fe from transferrin by lens epithelial cells in culture. Methods: Primary, secondary and tertiary cultures of canine lens epithelial cells and cultures obtained from cataractous lenses were studied. Uptake of 59Fe from transferrin by these cultured cells was measured. Transferrin receptor populations were determined in receptor-binding assays. Results: There was a distinct relationship between the amount of Fe-transferrin added and the amount of Fe taken up, which was linear for the primary cultures but significantly reduced for the secondary, tertiary and cataract cultures (252±21, 169±14, 153±14 and 96±2 ng Fe/mg protein, respectively).Transferring receptor expression in lens cell cultures was reduced 10-fold within 2 days of addition of serum to cells grown in low-Fe, serum-free medium for 1 week. Conclusions: The reduction of Fe uptake by the subcultured and cataract cell lines probably reflects a decrease in transferrin receptor expression and in the activity of an alternative pathway for Fe transferrin uptake occurring over time. This reduced Fe uptake may result from long-term exposure to relatively high Fe concentration in the media. A reduction in the expression of the transferrin receptor after incubation with high concentrations of Fe supports this conclusion.  相似文献   
996.
Summary PD153035 is a potent (Ki=6 pm) and specific inhibitor of the epidermal growth factor (EOF) receptor tyrosine kinase that suppresses tyrosine phosphorylation of the EGF receptor in A431 cells at nanomolar concentrations in cell culture. We have examined the pharmacokinetics of this compound and its ability to rapidly suppress phosphorylation of the EGF receptor in A431 human epidermoid tumors grown as xenografts in immunodeficient nude mice. Following a single i.p. dose of 80 mg/kg, the drug levels in the plasma and tumor rose to 50 and 22 M within 15 minutes. While the plasma levels of PD153035 fell below 1 M by 3 hours, in the tumors it remained at micromolar concentrations for at least 12 hours. The tyrosine phosphorylation of the EGF receptor was rapidly suppressed by 80–90% in the tumors. However receptor phosphorylation returned to control levels after 3 hours despite the continued presence of the drug at concentrations which, based on previousin vitro results, were predicted to maintain inhibition. EGF-stimulated tyrosine kinase activity in tumor extracts was decreased and recovered in parallel with the effects of PD153035 on receptor phosphorylation though the activity had reached only about half of the control activity after three hours. These results demonstrate the potential for using small molecule inhibitors to inhibit the EGF receptor tyrosine kinasein vivo, though a fair evaluation of their potential anti-cancer activity will have to wait for solutions to problems with sustained delivery which may allow us to maintain suppression of EGF receptor phosphorylation.  相似文献   
997.
Objective. To assess the utility of MR in detecting surgically induced Stener lesions (displaced thumb ulnar collateral ligaments) in cadaveric models. Design. Six cadaver thumbs had ulnar collateral ligament (UCL) tears created surgically. MR examinations (2D STIR and 3D GRASS) were performed identically on all specimens both before displacement (non-Stener) and after displacement (Stener lesion) of the UCL. The MR images were then randomly numbered. Each image was evaluated separately in blinded fashion by four musculoskeletal radiologists for the presence or absence of a Stener lesion. Each radiologist reinterpreted the images after an interval of several days. The interpretation was based on previously published criteria for Stener lesion diagnosis by MR. Results. The sensitivity of GRASS ranged from 0.17 to 0.67 with the most experienced reader scoring the lowest. The specificity of GRASS ranged from 0.33 to 1.0 (most experienced reader 0.67, 0.83). STIR had a sensitivity of 0.00–0.17 and a specificity of 0.53–0.83. The values for inter- and intraobserver agreement were measured. The intraobserver for GRASS was 0.27–0.75 (most experienced reader 0.75). Conclusions. 2D imaging is probably inadequate for the evaluation of Stener lesions. The most likely reason is that the STIR slice thickness of 3 mm limits resolution of small UCLs. The poor sensitivity and specificity of GRASS as well as poor interobserver agreement suggest that MR may not be sufficiently accurate for Stener lesion evaluation.  相似文献   
998.
Purpose To describe our preliminary experience with the addition of a GnRH antagonist (Nal-Glu) and exogenous gonadotropins (follicle stimulating hormone; FSH) to unstimulated IVF cycles.Method Seven spontaneously ovulatory women underwent eight unstimulated IVF cycles at our institution. They were treated with a single dose of Nal-Glu, 50 g/ kg, or with a combination of Nal-Glu, 50 g/kg, and exogenous FSH, 150–300 IU, during the late follicular phase of spontaneous cycles. They then received 10,000 IU of human chorionic gonadotropin (hCG) to time accurately follicle aspiration in unstimulated IVF cycles.Results Two women underwent three cycles with Nal-Glu alone on the day of hCG administration. One pregnancy resulted. Five women underwent five cycles with 3 to 6 days of daily Nal-Glu and FSH. Four of these cycles resulted in aspiration after the FSH dose was increased to 300 IU. Nal-Glu and FSH allowed continued development of the dominant follicle without the occurrence of luteinizing hormone (LH) surge.Conclusions (1) Nal-Glu alone given 18 hr prior to hCG did not interfere with continued follicle viability or with the attainment of pregnancy. (2) Simultaneous Nal-Glu and FSH allowed for continued growth and development of the dominant follicle without the occurrence of an LH surge. (3) This preliminary experience confirms the feasibility of this novel approach, which may ultimately enhance the efficacy of unstimulated IVF cycles by eliminating premature ovulation and maximizing control of gonadotropin delivery to the developing follicle.Presented at the 39th Meeting of The Society for Gynecologic Investigation, San Antonio, Texas, March 18–21, 1992.  相似文献   
999.
1000.
To determine the functions of retinoic acid receptors RAR and RXR, we have systematically knocked-out their genes by homologous recombination in the embryonic stem cells and generated null-mutant mice. This approach has allowed us to perform a genetic dissection of the retinoic acid signalling pathway.  相似文献   
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