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141.
PR de Jong RB Johanson P Baxen VD Adrians S van der Westhuisen PW Jones 《Canadian Metallurgical Quarterly》1997,104(5):567-571
OBJECTIVE: To assess the maternal and neonatal effects of upright compared with recumbent positions during delivery, in terms of defined outcome variables. DESIGN: A randomised controlled trial. SETTING: St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa. PARTICIPANTS: Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home. RESULTS: The trial showed that women who adopted the upright posture for delivery experienced less pain. perineal trauma and fewer episiotomies than those who delivered in the supine position. CONCLUSION: The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
142.
KL Childs FR Miller MM Cordonnier-Pratt LH Pratt PW Morgan JE Mullet 《Canadian Metallurgical Quarterly》1997,113(2):611-619
The Ma3 gene is one of six genes that regulate the photoperiodic sensitivity of flowering in sorghum (Sorghum bicolor [L.] Moench). The ma3R mutation of this gene causes a phenotype that is similar to plants that are known to lack phytochrome B, and ma3 sorghum lacks a 123-KD phytochrome that predominates in light-grown plants and that is present in non-ma3 plants. A population segregating for Ma3 and ma3 was created and used to identify two randomly amplified polymorphic DNA markers linked to Ma3. These two markers were cloned and mapped in a recombinant inbred population as restriction fragment length polymorphisms. cDNA clones of PHYA and PHYC were cloned and sequenced from a cDNA library prepared from green sorghum leaves. Using a genome-walking technique, a 7941-bp partial sequence of PHYB, was determined from genomic DNA from ma3 sorghum. PHYA, PHYB, and PHYC all mapped to the same linkage group. The Ma3-linked markers mapped with PHYB more than 121 centimorgans from PHYA and PHYC. A frameshift mutation resulting in a premature stop codon was found in the PHYB sequence from ma3 sorghum. Therefore, we conclude that the Ma3 locus in sorghum is a PHYB gene that encodes a 123-kD phytochrome. 相似文献
143.
144.
M Visser TB Harris J Langlois MT Hannan R Roubenoff DT Felson PW Wilson DP Kiel 《Canadian Metallurgical Quarterly》1998,53(3):M214-M221
BACKGROUND: Low muscle mass has been assumed to be associated with disability, but no studies confirming this association have been published. High body weight and high body mass index, both rough indicators of body fatness, have been shown to increase the risk for disability; however, the specific role of body fatness has not been studied. METHODS: The relations of skeletal muscle mass and percent body fat with self-reported physical disability were studied in 753 men and women aged 72 to 95 years. Cross-sectional data from biennial examination 22 (1992-1993) of the Framingham Heart Study were used. Body composition was assessed by dual-energy x-ray absorptiometry. Disability was scored as any versus none on a 9-item questionnaire. RESULTS: Total body and lower extremity muscle mass were not associated with disability in either men or women. However, a strong positive association between percent body fat and disability was observed. The odds ratio for disability in those in the highest tertile of body fatness was 2.69 (95% confidence interval 1.45-5.00) for women and 3.08 (1.22-7.81) for men compared to those in the lowest tertile. The increased risk could not be explained by age, education, physical activity, smoking, alcohol use, estrogen use (women only), muscle mass, and health status. Analyses restricting disability to mobility items gave similar results. CONCLUSIONS: In contrast to current assumptions, low skeletal muscle mass was not associated with self-reported physical disability. Persons with a high percent body fat had high levels of disability. Because it cannot be ruled out that persons with low skeletal muscle mass dropped out earlier in the study, prospective studies are needed to further assess the relationship between body composition and physical disability. 相似文献
145.
PW Kunst A Vonk Noordegraaf OS Hoekstra PE Postmus PM de Vries 《Canadian Metallurgical Quarterly》1998,19(4):481-490
Cytokine gene transfer into tumor cells has been shown to mediate tumor regression and antimetastatic effects in several animal models via immunomodulation. Therefore, clinical protocols have been developed to treat cancer patients with cytokine gene-modified tumor cells. We inserted the genes coding for the p35 and p40 chain of interleukin-12 (IL-12) in two independent eukaryotic expression vectors and transduced melanoma cells of 15 different primary tumor cultures with both plasmids by a ballistic gene transfer approach. Secreted IL-12 demonstrated strong bioactivity by inducing interferon-gamma release from peripheral blood lymphocytes upon coculture with cell culture supernatants after IL-12 gene transfer which could at least partly be blocked by IL-12-specific antisera. Further enrichment of transduced tumor cells by magnetic separation directly after gene transfer increased cytokine secretion from a mean of 119 pg in the unsorted to 507 pg IL-12 (24 h/10(8) cells) in the magnetically enriched cell fraction. Irradiation of these cells led to a further elevation of secreted IL-12 (mean 987 pg). Elevated IL-12 levels were detected over 7 days after irradiation in vitro. In a subsequent first clinical phase I study six patients with metastatic melanoma were vaccinated with autologous, interleukin-12 gene-modified tumor cells. Melanoma cells were expanded in vitro from surgically removed metastases, transduced by ballistic gene transfer, irradiated and were then injected subcutaneously (s.c.) at weekly intervals. Clinically, there was no major toxicity except for mild fever. All patients completed more than four s.c. vaccinations over 6 weeks and were eligible for immunological evaluation. Post-vaccination, peripheral mononuclear cells were found to contain an increased number of tumor-reactive proliferative as well as cytolytic cells as determined by a limiting dilution analysis in two patients. Two patients developed DTH reactivity against autologous melanoma cells and one had a minor clinical response. Biopsies taken from that patient's metastases revealed a heavy infiltration of CD4+ and CD8+ T lymphocytes. In conclusion, vaccination induced immunological changes even in a group of advanced, terminally ill patients. These changes can be interpreted as an increased antitumor immune response. 相似文献
146.
Asthma health status measurement in clinical practice: validity of a new short and simple instrument
Health status (Quality of Life) questionnaires for use in asthma are generally too long or complex for routine use. A new short and simple measure of health status in asthma has been developed for this purpose. There are two versions, one containing 30 items (AQ30) and the other 20 items (AQ20). This study examined their cross-sectional and longitudinal properties and compared them with those of two established measures--the St. George's Respiratory Questionnaire (SGRQ) and the Asthma Quality of Life Questionnaire (AQLQ). Ninety asthmatic patients (mean age 46 years) participated. Mean post-bronchodilator forced expiratory volume in one second (FEV1) was 73 +/- 25 (SD)% predicted at baseline. Questionnaire data were collected twice, 12 weeks apart. Diary records of peak expiratory flow rate (PEFR) and daily asthma were kept for 14 days. The new questionnaires each took 3 min or less to complete. At baseline they correlated well with the SGRQ and AQLQ and showed the same pattern of correlations with clinical measures of asthma. Change scores for the new questionnaires correlated with those for the established measures. There was no advantage of the AQ30 over the AQ20. The AQ20 provides a simple method for obtaining valid health status estimates of asthmatics in routine clinical practice and has properties similar to more complex research instruments. 相似文献
147.
PW Young DR Buckle BC Cantello H Chapman JC Clapham PJ Coyle D Haigh RM Hindley JC Holder H Kallender AJ Latter KW Lawrie D Mossakowska GJ Murphy L Roxbee Cox SA Smith 《Canadian Metallurgical Quarterly》1998,284(2):751-759
A radioiodinated ligand, [125I]SB-236636 [(S)-(-)3-[4-[2-[N-(2-benzoxazolyl)-N-methylamino]ethoxy]3-[125I]i odo phenyl]2-ethoxy propanoic acid], which is specific for the gamma isoform of the peroxisomal proliferator activated receptor (PPARgamma), was developed. [125I]SB-236636 binds with high affinity to full-length human recombinant PPARgamma1 and to a GST (glutathione S-transferase) fusion protein containing the ligand binding domain of human PPARgamma1 (KD = 70 nM). Using this ligand, we characterized binding sites in adipose-derived cells from rat, mouse and humans. In competition experiments, rosiglitazone (BRL-49653), a potent antihyperglycemic agent, binds with high affinity to sites in intact adipocytes (IC50 = 12, 4 and 9 nM for rat, 3T3-L1 and human adipocytes, respectively). Binding affinities (IC50) of other thiazolidinediones for the ligand binding domain of PPARgamma1 were comparable with those determined in adipocytes and reflected the rank order of potencies of these agents as stimulants of glucose transport in 3T3-L1 adipocytes and antihyperglycemic agents in vivo: rosiglitazone > pioglitazone > troglitazone. Competition of [125I]SB-236636 binding was stereoselective in that the IC50 value of SB-219994, the (S)-enantiomer of an alpha-trifluoroethoxy propanoic acid insulin sensitizer, was 770-fold lower than that of SB-219993 [(R)-enantiomer] at recombinant human PPARgamma1. The higher binding affinity of SB-219994 also was evident in intact adipocytes and reflected its 100-fold greater potency as an antidiabetic agent. The results strongly suggest that the high-affinity binding site for [125I]SB-236636 in intact adipocytes is PPARgamma and that the pharmacology of insulin-sensitizer binding in rodent and human adipocytes is very similar and, moreover, predictive of antihyperglycemic activity in vivo. 相似文献
148.
149.
Characterization of recombinant human fibroblast growth factor (FGF)-10 reveals functional similarities with keratinocyte growth factor (FGF-7) 总被引:1,自引:0,他引:1
A newly identified member of the fibroblast growth factor (FGF) family, designated FGF-10, is expressed during development and preferentially in adult lung. The predicted FGF-10 protein is most related to keratinocyte growth factor (KGF, or FGF-7). The latter is unique among FGFs in that it binds and signals only through the FGF receptor (FGFR2b) isoform KGF receptor (KGFR) expressed specifically by epithelial cells. In order to examine the biological and biochemical properties of human FGF-10, we isolated the cDNA and expressed its encoded protein in bacteria. The recombinant protein (rFGF-10) was a potent mitogen for Balb/MK mouse epidermal keratinocytes with activity detectable at 0.1 nM and maximal at around 5 nM. Within this concentration range, FGF-10 did not stimulate DNA synthesis in NIH/3T3 mouse fibroblasts. rFGF-10 bound the KGFR with high affinity comparable to that of KGF, and did not bind detectably to either the FGFR1c (Flg) or FGFR2c (Bek) receptor isoforms. The mitogenic activity of FGF-10 could be distinguished from that of KGF by its different sensitivity to heparin and lack of neutralization by a KGF monoclonal antibody. These results indicate that FGF-10 and KGF have similar receptor binding properties and target cell specificities, but are differentially regulated by components of the extracellular matrix. 相似文献
150.
We have seen a case of hyperventilation which appeared to have been caused by contact with an insecticide. Pathophysiology, epidemiology and treatment are discussed. Familiarity with the clinical symptoms greatly facilitate diagnosis, especially in emergency situations. 相似文献