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21.
Between July 1985 and January 1990, pseudomonas scepticaemia occurred in 19 out of 584 patients with AIDS attending the Westminster and St Stephen's AIDS Unit, London, UK. Ten of these 19 were being treated for active cytomegalovirus infection. Fourteen of the 19 patients had a central venous catheter in situ, which was the source of infection in 11. Seven patients died. Mortality was significantly greater in those patients infected with Pseudomonas aeruginosa, in those patients whose source of infection was not the central venous line, and in those patients whose central line was not removed.  相似文献   
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The prognostic significance of the tumour activities of 2 steroid receptors, those for oestrogen (ER) and for progestogen (PgR), has been studied in 372 patients with breast cancer, in whom follow-up was available for 2-6 years (median 41 months). Of 252 patients with operable disease, 75.8 per cent had ER-positive tumours and 46.4 per cent had PgR-positive tumours, though a small additional fraction (6.3 per cent) had an equivocal PgR assay result. For the 236 patients with unequivocal receptor status, the relationships between disease-free interval or overall survival and receptor activity and other factors were evaluated by univariate and multivariate analyses. The latter revealed that only tumour size, node status, menstrual status and ER status related significantly to both disease-free interval and survival, though adjuvant therapy also related to disease-free interval, and tumour grade related to survival. It is concluded that measurements of PgR activity do not add to the prognostic significance of ER status.  相似文献   
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Many physiological variables known or thought to affect erythrocyte Na+,K+-cotransport are altered in pregnancy. The interrelationships of Na+,K+-cotransport and pregnancy were therefore examined. Values were elevated by more than 30% in both second and third trimesters with a return towards non-pregnant levels in the postpartum period. Although pregnancy was also associated with elevated plasma cholesterol, renin activity and aldosterone, there was no significant relationship within the pregnant group between Na+,K+-cotransport and any of these factors. No change could be demonstrated in Na+,K+-cotransport values after 7 days of either high (greater than 250 mmol/day) or low (less than 50 mmol/day) sodium intake and values for those who developed pregnancy-associated hypertension (PAH, pre-eclampsia) were not significantly different from those in continuously normotensive women in either the second or the third trimesters of pregnancy.  相似文献   
26.
Several systems have been developed to monitor and feedback information about a client's responses to psychotherapy as a method of enhancing client outcome. The current study divided 1020 clients into four groups (two experimental and two control) to determine if feedback regarding client progress, when provided to a therapist, affected client outcome and number of sessions attended. Results showed that feedback increased the duration of treatment and improved outcome for clients identified as potential treatment failures thereby replicating an earlier study using nearly identical methodology. Nearly twice as many clients in the feedback group achieved clinically significant or reliable change and fewer were classified as deteriorated by the time treatment ended. For those clients who were predicted to have a positive response to treatment, feedback to therapists resulted in an equal number of treatment sessions and equivalent outcomes compared to the no feedback controls. The results are discussed in terms of quality management in routine clinical practice and the need to base treatment decisions on clients' response to treatment rather than arbitrary session limits. Suggestions for additional research aimed at enhancing the effects of feedback on client outcome are made. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
27.
The exact opioid-sensitive receptors participating in EtOH-seeking behaviors remains unclear. Previous studies have reported higher densities of micro-opioid receptor binding in the nucleus accumbens (NACC) of P relative to NP rats; however, no differences were seen in delta-receptor binding. In contrast to the NACC, substantially lower levels of micro-receptor binding have been observed in the ventral tegmental area (VTA) of both P and NP rats, albeit no line differences have been observed. In the present study, opioid receptors in the NACC, VTA, and hippocampus were evaluated for their capacity to regulate both EtOH- and saccharin-motivated behaviors in the genetically selected alcohol-preferring (P) rat. To accomplish this, nalmefene, an opiate antagonist with preferential binding affinity for the micro-opioid receptor was unilaterally or bilaterally infused during concurrent availability of 1 h daily EtOH (10% v/v) and saccharin (0.025 or 0.050% w/v) solutions. Rats performed under a two-lever fixed ratio (FR) schedule in which four responses on one lever produced the EtOH solution, and four on a second lever produced the saccharin solution. The results demonstrated that when responding maintained by both EtOH and saccharin are matched at basal levels, unilateral (1-60 microg) or bilateral (0.5-10 microg) microinjections of nalmefene into the NACC produced selective dose-dependent reductions on responding maintained by EtOH. Unilateral (40, 60 microg) and bilateral (10 microg) VTA infusions were also observed to selectively reduced EtOH responding; however, greater nalmefene doses were required and the magnitude of suppression on EtOH responding was markedly less compared with the NACC. The greater sensitivity of nalmefene to suppress EtOH responding in the NACC is likely due to the greater number of opioid receptors in the NACC relative to the VTA. Only bilateral infusion of the 40 microg dose in the NACC and VTA suppressed responding maintained by both EtOH and saccharin. In contrast, intrahippocampal infusions dose dependently suppressed EtOH- and saccharin-maintained responding over a range of doses (1-20 microg). The present study provides evidence that nalmefene suppresses EtOH-motivated behaviors via blockade of opioid receptors within the NACC and VTA, and under various dose conditions both reinforcer and neuroanatomical specificity can be observed.  相似文献   
28.
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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The radiopacity of ingested medications   总被引:1,自引:0,他引:1  
We investigated prospectively the radiopacity of 312 pills found on a university hospital formulary by first radiographing them through 15 and 25 cm of water to duplicate the radiodensity of the human body. The pills that were radiodense through water were studied in a human cadaver model, and their densities were quantified by computed tomography (CT). Thirty-five of 312 pills were radiopaque in 15 cm or more of water, and 23 of these pills were radiopaque on a plain radiograph when placed in the stomach of a cadaver. Common mnemonics used to identify radiopaque pills were found to be incomplete and inadequate. Chloral hydrate, iron-containing preparations, calcium carbonate, iodinated compounds, acetazolamide, busulfan, and potassium preparations were consistently radiopaque. Antihistamines, phenothiazines, and tricyclic antidepressants demonstrated varying radiopacity. There was varying radiopacity among the same medications made by different manufacturers. The presence of an enteric coating did not assure that the pill would be radiopaque. Merely radiographing a pill that has been placed on a standard radiograph cassette will make pills that are actually radiolucent in the body appear radiopaque. This test cannot be used to predict radiopacity in vivo. Visibility when radiographed through 15 cm or more of water and a CT radiodensity of more than 1,300 Hounsfield units are predictors of the radiopacity of a pill in the stomach of a cadaver model on a standard KUB radiograph. Variables, such as the size of the patient, the arrangement of pills in the stomach, air contrasting a pill, and the specific composition of the enteric coating or the pillmatrix, affect the radiodensity of pills.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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