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51.
OBJECTIVE--To assess the implementation of action protocols dictated by antenatal risk factors noted at the initial (booking) antenatal visit. DESIGN--Retrospective study of 2000 women delivered between 1 March 1990 and 29 March 1991. SETTING--Maternity department of a district general hospital supporting a multiethnic population in inner London. MAIN OUTCOME MEASURES--Comparison of clinical actions performed against those dictated by the department''s protocols. Analysis according to clinical importance, gestation at booking, maternal age, parity, birth order, ethnic origin, and certainty of gestational age. RESULTS--Interobserver agreement between the two auditors was good (kappa statistic for risk factors detected, 0.78; for actions generated, 0.80). Of the 15,658 actions dictated by department protocols, 3673 (23.5%) were actually performed by the clinicians. The 63 combinations of risk factors and actions believed by consultants to be of particular clinical importance had an action rate of 28.3% compared with 18.6% for those considered less important (p < 0.001). Mothers who first visited the hospital antenatal clinic at or before 24 weeks'' gestation had 25.2% of relevant protocols fulfilled (p < 0.001). Compliance was significantly improved in women aged 36 or over (32.4%), black women (24.9%), and cases of uncertain gestation (24.5%). Parity and birth order were not associated with an altered action rate. Ethnic origin deemed as "other" (than white, black, Asian, or oriental) or "unknown" was associated with poor compliance (19.3%). CONCLUSIONS--Compliance to a set of agreed protocols was poor even though a computer system was available and a protocol manual had been distributed. Protocols were more likely to be implemented in women who booked early and in some groups of women deemed at high risk including older mothers, black women, and those denoted as having uncertain gestational age. 相似文献
52.
Thousands of tonnes of dry oil palm trunks will be produced annually in Malaysia after about 1990. A project was initiated to study the feasibility of converting palm trunks into charcoal. Carbonisation was done at terminal temperatures of 400–550°C with holding times of 1–3 h and at two heating rates. From laboratory-scale pyrolysis studies, it was found that holding time does not affect the quantity and quality of the charcoal produced, while heating rate has a minor influence. However, as terminal temperature increases, both yield and volatile content decrease while the fixed carbon content increases. The calorific value and ash contents are independent of the parameters studied and their respective values are 4032 kcal/kg and 37.2%. Since the calorific value is low and the ash content high, it is concluded that oil palm trunks are not suitable for the production of charcoal fuel. 相似文献
53.
L V Krasheninnikova G V Rassadina S N Kirsanova L M Khromova V M Iusibov I r Pak Chun V M Andrianov E S Piruzian 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1991,(11):17-20
The genetic constructions based on integrative vector pGV3850 were used to introduce bacterial genes xyl and T-cyt into potato cells. The transformation was carried out using the leaf-disc method with modifications. A special system for obtaining regenerants from explants of potato in vitro plants or calli has been designed that permitted the selection of transgenic shoots. The presence of the genes in potato genome has been proved by testing the NPTII and glucoisomerase activities. The transgenic plants expressing T-cyt gene differed from the wild type in sharp decrease of the apical dominance. 相似文献
54.
55.
Kenneth H. Astrin Cecilia A. Warner Han-Wook Yoo Paul J. Goodfellow Shih-Feng Tsai Robert J. Desnick 《Human genetics》1991,87(1):18-22
Summary Uroporphyrinogen III synthase [UROS; hydroxymethylbilane hydro-lyase (cyclizing), EC 4.2.1.75] is the fourth enzyme in the human heme biosynthetic pathway. The recent isolation of the cDNA encoding human UROS facilitated its chromosomal localization. Human UROS sequences were specifically amplified by the polymerase chain reaction (PCR) from genomic DNA of two independent panels of human-rodent somatic cell hybrids. There was 100% concordance for the presence of the human UROS PCR product and human chromosome 10. For each of the other chromosomes, there was 19%–53% discordance with human UROS. The chromosomal assignment was confirmed by Southern hybridization analysis of DNA from somatic cell hybrids with the full-length UROS cDNA. Using human-rodent hybrids containing different portions of human chromosome 10, we assigned the UROS gene to the region 10q25.2 q26.3. 相似文献
56.
Lymphocyte activation and serine-esterase induction following recombinant interleukin-2 infusion for lymphomas and acute leukaemias 总被引:3,自引:0,他引:3
Seah H. Lim Colin Worman Andrew Jewell Chris Tsakona Frank J. Giles Anthony Goldstone 《Cancer immunology, immunotherapy : CII》1991,33(2):133-137
Summary C57BL mice inoculated with radiation leukemia virus (RadLV) develop preleukemic cells long before the onset of leukemia. These cells are potentially immunogenic but fail to elicit an immune response in the host because of the appearance of virus-specific suppressor T cells. We have studied the effect of polysaccharide K (PSK) on the generation of RadLV-specific cell-mediated immune responses in vitro. Long-term exposure to PSK in culture potentiated the ability of immunized T cells to respond to a RadLV-induced lymphoma. It also abrogated the suppressive activity of suppressor T cells and simultaneously boosted the ability of reactive T cells to respond. The dual immunostimulating activity of PSK resulted in the generation of T cytotoxic lymphocytes that could lyse lymphoma cells in vitro. The results suggest that PSK could be used as a prophylactic immune response modifier in preleukemia. 相似文献
57.
Reaction of pyruvate kinase with the new nucleotide affinity labels 8-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-diphosphate and 5'-triphosphate 总被引:1,自引:0,他引:1
Two new reactive nucleotides have been synthesized and characterized: 8-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-diphosphate and 5'-triphosphate (8-BDB-TADP and 8-BDB-TATP). ADP or ATP was converted to 8-thio-ADP (-ATP) via 8-bromo-ADP (-ATP), followed by condensation with 1,4-dibromobutanedione. Rabbit muscle pyruvate kinase is inactivated by both reagents in a biphasic manner with an initial rapid loss of 75% activity, followed by a slow total inactivation. The initial fast reaction with both compounds exhibits nonlinear dependence on reagent concentration, indicating formation of a reversible enzyme-reagent complex prior to covalent attachment. The presence of the gamma-phosphoryl group improves the performance of the affinity label: KI values for the fast phase are similar (about 100 microM), whereas kmax for 8-BDB-TATP is about three times greater than that of 8-BDB-TADP (0.286 min-1 vs 0.0835 min-1). After an 80-min incubation with 175 microM of either reagent, about 2 mol/mol of subunit is incorporated with 76% inactivation caused by 8-BDB-TADP and 97% inactivation by 8-BDB-TATP. Loss of activity is prevented by substrates, with the best protection afforded by a combination of ATP, Mn2+, K+, and phosphoenolpyruvate. Reaction of pyruvate kinase with either compound in the presence of protecting ligands leads to incorporation of about 1 mol of reagent/mol of subunit with only about 15% loss of activity. These results suggest that 8-BDB-TADP and 8-BDB-TATP react with two groups on the enzyme, one of which is at or near the active site.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
59.
Parulekar SJ Semones GB Rolf MJ Lievense JC Lim HC 《Biotechnology and bioengineering》1986,28(5):700-710
Continuous cultures of Saccharomyces cerevisiae are known to exhibit oscillatory behavior in the oxidative region. Important findings of a series of experiments conducted to identify the causes for initiation of and the means for elimination of oscillations in these cultures are reported in this paper. These oscillations are seen to be connected to the growth kinetics of the microorganism and are induced at very low glucose concentrations and at dissolved oxygen (DO) levels that are neither high nor low (DO values between 20 and 78% air saturation at a dilution rate of 0.2 h(-1) and pH of 5.5 at 30 degrees C). The oscillatory behavior is encountered over a range of dilution rates (0.09-0.25 h(-1) at 30 degrees C for pH = 5.5 and DO = 50% air saturation). The oscillations can be eliminated by raising the DO level above a critical value or by lowering the DO level below a critical value. 相似文献
60.
Single crystals have been prepared of Paracoccus denitrificans amicyanin, a blue copper protein that serves as an electron acceptor for methylamine dehydrogenase. The crystals belong to the monoclinic space group P2(1), and have unit cell parameters a = 20.90 A, b = 56.61 A, c = 27.55 A and beta = 96.41. There is one molecule in the asymmetric unit. The crystals diffract to beyond 1.5 A resolution. 相似文献