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1.
The ability of a number of heterocyclic metal chelators to deliver zinc into red cells, to release the liganded zinc to haemoglobin and thereby cause a left shift in the oxygen dissociation curve of intact red cells has been investigated. Incubation of neutrally charged zinc-pyrone and zinc-pyridin-2-one complexes with red cells led to the rapid accumulation of zinc within cells, whereas unliganded zinc in the form of zinc acetate, zinc chloride or zinc sulphate accumulated only slowly. The rate at which zinc was delivered to red cells by pyrone and pyridin-2-one ligands increased with increasing lipid solubility of the ligands. The uptake of zinc into both normal adult and sickle red cells was associated with a dose-dependent increase in the oxygen affinity of haemoglobin. The degree of left shift in the oxygen dissociation curve following the incubation of red cells with zinc-pyrone and -pyridin-2-one complexes suggests that these complexes may find application as agents to increase the oxygen affinity of haemoglobin in sickle cell disease and thereby decrease the probability of intravascular sickling at low tissue oxygen tensions. Ethylmaltol appears to be a particularly useful agent due to its known low toxicity.  相似文献   
2.
Proteins that enter the secretory pathway play important roles in virulence and pathogenesis in Candida albicans, but our understanding of the trafficking of these proteins is in its early stages. In Saccharomyces cerevisiae, dominant negative alleles of YPT1 and SEC4 interrupt secretory traffic at pre- and post-Golgi steps, respectively. We therefore used a dominant negative genetic approach to examine the intracellular trafficking of several proteins associated with virulence or azole resistance. When the dominant negative ypt1(N121I) allele of C. albicans was overexpressed, yellow-fluorescent protein (YFP) tagged forms of two plasma membrane transporters (Cdrlp and Ftrlp) and the vacuolar membrane ABC transporter Mltlp accumulated in intracellular structures that appeared related to the ER, but localization of Cdc10p and Int1p was unaffected. When the dominant negative sec4(S28N) allele of C. albicans was overexpressed, Cdrlp and Ftrlp accumulated intracellularly, and localization of Mltlp, Cdc10p and Int1p was unaffected. These results imply that (i) Cdrlp and Ftrlp are transported to the plasma membrane by the general secretory pathway, (ii) Mlt1p enters the secretory pathway but is diverted to the vacuole at an early post-Golgi step, and (iii) like Cdc10p, Int1p does not enter the general secretory pathway.  相似文献   
3.
The new complaints procedures which local authority social services departments have been required to introduce represent an important mechanism for managing the change of culture associated with recent community care reforms. They also represent a new genre in mechanisms of redress for welfare recipients. This paper reports the findings of a study which has observed considerable diversity in the ways in which local authorities are interpreting the nature and purposes of the new procedures and, in particular, the functions of review panels established under those procedures. Variations in the composition of panels, in the style of review panel proceedings, in perceptions of the panels' powers, and in the ways that complaints and complainants are constituted are all discussed. Attention is drawn to four competing interpretations of the review panels' role and to the need for these to be clarified and prioritised.  相似文献   
4.
Infants living in an orphanage (n = 22) in Romania were assessed on the Test of Sensory Functions in Infants (TSFI). Testing of the institutionalized infants was done before and 6 months after an enriched caregiver intervention program. Results showed significant changes in areas of reactivity to tactile deep pressure, visual-tactile integration, oculomotor control, reactivity to vestibular stimulation and total test responses. No significant changes occurred in the area of adaptive motor functions. Effects of sensory deprivation resulting from institutional settings and changes that can occur from enriched caregiver environments are discussed.  相似文献   
5.
In the differential clinical diagnosis of mammary neoplasms, adenocarcinoma can safely be excluded only after biopsy and microscopic study.In a series of 177 cases of mammary cancer treated by surgery with x-ray therapy, 30.4 per cent of the patients are alive three years or more after treatment; 18 per cent five years or longer.Only one of every four patients presents herself with a lesion still within the breast. Exclusive of Group I this results in a cure in 86.1 per cent in Group II and 15.4 per cent in Group III. The mortality rate then increases five and one-half times as spread occurs beyond the breast.The results of irradiation therapy for curative purposes in recurrent or metastatic mammary adenocarcinoma are poor.
Percentage of cure by stages.
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In some patients with mental retardation, a Q-tip pap smear obtained blindly from the upper vagina may be the only cytologic smear obtainable without subjecting the patient to heavy sedation or to examination under anesthesia. The efficacy of blind Q-tip smears has not been previously determined. Of 31 Q-tip smears obtained from patients with CIN, the Q-tip smear identified the abnormality in 10 (32%) patients. For those patients who will not submit to examination without anesthesia or sedation, routine screening with multiple smears, obtained on an annual basis has the potential to identify many cases of CIN which otherwise would not be identified at all, and in certain patients, this method outweighs the risks of heavy sedation or general anesthesia. Because of the greatly reduced sensitivity of the Q-tip pap, every effort should be made to help the patient and/or her family or guardian to understand the implications and risks of this method. However, if an examination under anesthesia is performed for other indications, a complete gynecologic examination and a direct smear should be obtained at that time.  相似文献   
9.
Syntheses and relative cadmium mobilizing properties are described for three new monoaralkyl esters (HOOCCH(SH)CH(SH)COOR, where R = phenylethyl ((CH2)2C6H5), MPhEDMS; R = 3-phenylpropyl ((CH2)3C6H5), MPhPDMS; and R = 2-phenoxyethyl ((CH2)2OC6H5), MPhOEDMS) of meso-2,3-dimercaptusuccinic acid. These were prepared by the reaction of the corresponding alcohol with meso-2,3-dimercaptosuccinic acid (DMSA) in aqueous HCl. When administered intraperitoneally to cadmium-loaded mice at 0.50 mmol/kg/day for four consecutive days, all induced significant reductions in the whole body cadmium levels. MPhEDMS, 60%; MPhPDMS, 66%; and MPhOEDMS, 58% in comparison with control levels. At the same dosage monoisoamyl meso-2,3-dimercaptosuccinate (Mi-ADMS) and a dithiocarbamate, sodium N-benzyl-4-O-(β-D-galactopyranosyl)-d -glucamine-N-carbodithioate (BLDTC) induced reductions of 65% and 57%, respectively. Hepatic and renal cadmium were also depleted significantly, while brain cadmium levels were unchanged. These compounds induced a significant reduction in the cadmium levels of the spleen, and one, MPhOEDMS, produced a 10% decrease in pancreatic cadmium. The manner in which the later injections removed smaller fractions of the total body cadmium is consistent with a bodily distribution of these compounds by which they are concentrated primarily in the kidneys and the liver, with much smaller amounts reaching other organs. It is proposed that these compounds enter renal and hepatic cells through an anion transport system.  相似文献   
10.
We have previously reported a method for assessing functional deficits in rats after contusive spinal cord injury in which a Combined Behavioral Score (CBS) is calculated that is indicative of the overall percent deficit (Exp. Neurol., 88: 123-134, 1985). The test battery used includes several neurologic tests as well as the Motor Score in which use of the hindlimbs in locomotion is graded. In this report we present correction criteria in order to reduce potential interlaboratory variability in assessing functional deficit by the CBS. Groups of rats were subjected to contusive injury using a weight drop technique. The calculated CBS at 4 weeks was compared to that obtained if the Motor Score was over- or underestimated by 1 grade. The results indicated a considerable effect on the calculated CBS, especially when the Motor Score was underestimated in mildly injured animals. Behavioral test data were examined in terms of the distribution of the responses to the various other behavioral tests in relation to the Motor Score. The results were used to develop a set of correction criteria that minimized the effects on the CBS of subjective errors in the Motor Score.  相似文献   
StagePatients TreatedPer Cent Cures
I1100.0
II and IIa4086.1
III and IIIa13015.4
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