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71.
OBJECTIVE--To assess the quality of toilet facilities available for disabled people in a large provincial teaching hospital. DESIGN--Survey of toilet facilities for patients on the wards and in the outpatient department. SETTING--Teaching hospital in Leeds. RESULTS--Although the quality of toilet facilities varied, none met the standards recommended by the British Standards Institution. The worst facilities were found on a ward accommodating elderly patients, where the toilets were unsuitable for use by disabled people and bedside commodes had to be used instead. CONCLUSION--Toilet provision within a major hospital failed to meet standards required for disabled people. Admission to hospital may therefore result in loss of independence and dignity. If hospitals are to be centres of excellence, greater consideration must be given to the requirements of disabled people in the design of new wards, and current inadequate facilities should be upgraded.  相似文献   
72.
73.
The rate of fermentation of glucose by a polyploid strain of Saccharomyces cerevisiae growing in a defined salts medium depends on the availability of NH4++. Its decline after exhaustion of the nitrogen source corresponded with the ability of the cells to accumulate the glucose analogue 2-deoxyglucose. Addition of NH4++to a nitrogen-depleted culture stimulated both glucose utilization and 2-deoxyglucose uptake. Since stimulation was inhibited by cycloheximide, maintenance of glucose transport during fermentation is dependent on protein synthesis.  相似文献   
74.
Haptoglobin and transferrin (TF) types were determined for 134 patients with leukaemia of the four most common types: acute lymphocytic (ALL), chronic lymphocytic (CLL), acute myelocytic (AML) and chronic myelocytic leukaemia (CML). The phenotype HP1 was found to have an increased incidence in the total patient group due to an increased incidence in those with AML, ALL and CML compared with controls, but not in those with CLL. Although tests of association applied to each of the samples of the four common types of leukaemia produced no significant chi 2 values, they did indicate that the relative incidence (RI) was just under 2 for the groupings of the acute forms ALL and AML, the myelocytic forms AML and CML and for the combination of ALL, AML and CML, respectively. All these associations were statistically significant (p less than 0.05). Analysis of TF subtypes and leukaemia indicated a significantly increased frequency of TF C1C1 among leukaemia patients compared with controls (p less than 0.005). Analysis of the samples of each of the four common types suggested that while the RI was raised in all but ALL patients, the association was significant only in AML patients (p less than 0.05). However, when the two myelocytic types were combined the RI was 2.3 and the association was highly significant (p less than 0.005). No such association could be detected in the lymphocytic forms.  相似文献   
75.
Intact sediment cores were obtained from three New York lakes in May, July, and October 1981. Radioactive S (as 35SO 4 2− ) was added to the overlying water and cores were incubated without atmospheric exchange for one week near lake bottom temperatures. Headspace flux of 02 as an index of sediment respiration rates varied among lakes and seasonally within lakes. Acidic South Lake had the lowest respiration rate at all seasons and also the smallest net incorporation of the 35SO 4 2− . Summer net isotope transformation into ester sulfate and non-HI reducible S (pyrite and C-bonded S) constituents was 88.6%, 89.4%, and 59.7% of total sediment isotope for Oneida, Deer, and South, respectively. Seasonal variation of net isotope incorporation was observed in each lake as were differences in 35SO 4 2− partitioning into major S pools. Of the S constituents analyzed, HCl digestible S (volatile sulfides) was the smallest pool, while ester sulfate and non-HI reducible S together accounted for greater than 50% of S isotope transformation in all lakes. In addition, ester sulfate is the major product of dissolved SO 4 2− transformation and its formation results in less alkalinity generation than the formation of non-HI reducible S constituents. Thus ester sulfate transformation processes must be considered in calculating alkalinity generation by lake sediments. Financial support provided by Office of Water Research Technology (Project No. 13-096-NY). Financial support provided by Office of Water Research Technology (Project No. 13-096-NY).  相似文献   
76.
The attractive forces between polar lipid bilayers.   总被引:2,自引:2,他引:0       下载免费PDF全文
Long-range attractive forces between lipid bilayers are not well described by the Lifshitz theory of Van der Waals forces between macroscopic media. It is shown that when correlations between polar headgroups are taken into account, the predicted forces take a qualitatively different form consistent with the measured data.  相似文献   
77.
In this study, we compared the effects of 2,6-dideoxy-2,6-imino-7-O-(beta-D-glucopyranosyl)-D-glycero-L-gulohep titol (MDL) to those of the glucosidase I inhibitor, castanospermine, on the purified processing enzymes glucosidases I and II. WE also compared the effects of these two inhibitors on glycoprotein processing in cell culture using influenza virus-infected Madin-Darby canine kidney cells as a model system. With the purified processing enzymes, castanospermine was a better inhibitor of glucosidase I than of glucosidase II, whereas MDL is more effective against glucosidase II than glucosidase I. In cell culture at the appropriate dose, MDL also preferentially affected glucosidase II. Thus, at 250 micrograms/ml MDL, the major [3H]glucose-labeled (or [3H]mannose-labeled) glycopeptide from the viral hemagglutinin was susceptible to endoglucosaminidase H, and the oligosaccharide liberated by this treatment was characterized as a Glc2Man7-9GlcNAc on the basis of size, resistance to digestion by glucosidase I (but sensitivity to glucosidase II), methylation analysis, and Smith degradation studies. These data indicate that at appropriate concentrations of MDL (250 micrograms/ml), one can selectively inhibit glucosidase II in Madin-Darby canine kidney cells. However, at higher concentrations of inhibitor (500 micrograms/ml), both enzymes are apparently affected. Since MDL did not greatly inhibit the synthesis of lipid-linked saccharides or the synthesis of protein or RNA, it should be a useful tool for studies on the biosynthesis and role of N-linked oligosaccharides in glycoprotein function.  相似文献   
78.
Five lighthorse mares were actively immunized against gonadotropin releasing hormone (GnRH) to determine the relative importance of this hypothalamic hormone in the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Five mares immunized against the conjugation protein served as controls. Mares were initially immunized in November and received secondary immunizations 4 wk later, and then at 6-wk intervals until ovariectomy in June. All mares immunized against GnRH exhibited an increase (p less than 0.01) in the binding of tritiated GnRH by plasma, an indication that antibodies against this hormone had been elicited. Concentrations of LH, FSH and progesterone in weekly blood samples were lower (p less than 0.05) in GnRH-immunized mares than in controls after approximately 4 mo of immunization. However, the LH concentrations were affected to a greater degree than were FSH concentrations. All five control mares exhibited normal cycles of estrus and diestrus in spring, whereas no GnRH-immunized mare exhibited cyclic displays of estrus up to ovariectomy. All mares were injected intravenously with a GnRH analog (which cross-reacted less than 0.1% with the anti-GnRH antibodies) in May, after all control mares had displayed normal estrous cycles, to characterize the response of LH and FSH in these mares; two days later, the mares were injected with GnRH. The LH response to the analog, which was assessed by net area under the curve, was lower (p less than 0.01) by approximately 99% in mares immunized against GnRH than in control mares. In contrast, the FSH response to the analog was similar for both groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
Complementation was examined among various types of I-cell disease and pseudo-Hurler polydystrophy by monitoring N-acetylglucosaminylphosphotransferase activity in multinucleated cells produced by fusing pair combinations of cultured skin fibroblasts. Patients with the classical forms of these disorders (5 I-cell disease and 3 pseudo-Hurler polydystrophy cell lines) comprised one complementation group and 5 cell lines from patients with variant forms of pseudo-Hurler polydystrophy comprised a distinct complementation group. In the first group, total or partial deficiency of the transferase activity was demonstrated with both natural (lysosomal enzymes) and artificial (alpha-methylmannoside) acceptor substrates with low Vmax but apparently normal Km values for the donor (UDP-GlcNAc) and acceptor (alpha-methylmannoside) substrates. The activity toward artificial substrate could be inhibited by adding exogenous lysosomal enzyme preparations to the reaction mixture. In the second group, the cells demonstrated deficiency of the transferase activity toward lysosomal enzyme acceptors but had normal activity toward alpha-methylmannoside acceptor and this activity could not be inhibited by the addition of exogenous lysosomal enzyme preparations. These findings suggest that N-acetylglucosaminylphosphotransferase is composed of at least two distinct subunits, a catalytic subunit which is absent or defective in the first complementation group, and a recognition subunit which is altered or deficient in the second group.  相似文献   
80.
Localisation of light chain and actin binding sites on myosin   总被引:6,自引:0,他引:6  
A gel overlay technique has been used to identify a region of the myosin S-1 heavy chain that binds myosin light chains (regulatory and essential) and actin. The 125I-labelled myosin light chains and actin bound to intact vertebrate skeletal or smooth muscle myosin, S-1 prepared from these myosins and the C-terminal tryptic fragments from them (i.e. the 20-kDa or 24-kDa fragments of skeletal muscle myosin chymotryptic or Mg2+/papain S-1 respectively). MgATP abolished actin binding to myosin and to S-1 but had no effect on binding to the C-terminal tryptic fragments of S-1. The light chains and actin appeared to bind to specific and distinct regions on the S-1 heavy chain, as there was no marked competition in gel overlay experiments in the presence of 50-100 molar excess of unlabelled competing protein. The skeletal muscle C-terminal 24-kDa fragment was isolated from a tryptic digest of Mg2+/papain S-1 by CM-cellulose chromatography, in the presence of 8 M urea. This fragment was characterised by retention of the specific label (1,5-I-AEDANS) on the SH1 thiol residue, by its amino acid composition, and by N-terminal and C-terminal sequence analyses. Electron microscopical examination of this S-1 C-terminal fragment revealed that: it had a strong tendency to form aggregates with itself, appearing as small 'segment-like' structures that formed larger aggregates, and it bound actin, apparently bundling and severing actin filaments. Further digestion of this 24-kDa fragment with Staphylococcus aureus V-8 protease produced a 10-12-kDa peptide, which retained the ability to bind light chains and actin in gel overlay experiments. This 10-12-kDa peptide was derived from the region between the SH1 thiol residue and the C-terminus of S-1. It was further shown that the C-terminal portion, but not the N-terminal portion, of the DTNB regulatory light chain bound this heavy chain region. Although at present nothing can be said about the three-dimensional arrangement of the binding sites for the two kinds of light chain (regulatory and essential) and actin in S-1, it appears that these sites are all located within a length of the S-1 heavy chain of about 100 amino acid residues.  相似文献   
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