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41.
When children are ill enough to require admission to paediatric intensive care, parents may become distressed about their child's medical condition and this distress may be compounded by the unfamiliar nature of the highly technological environment Parents of children who are sick enough to warrant intubation are particularly likely to be exposed to a frightening array of technological equipment Seventy-one parents of intubated and non-intubated children completed the Parental Stressor Scale Paediatnc Intensive Care Unit (PSS PICU) Overall the findings suggest that parents were most distressed (a) by the painful procedures to which their children were subjected, (b) by the sights and sounds of the intensive care unit and (c) by their children's reactions to intensive care The behaviour of staff towards parents and the way that staff communicated with them caused the least distress When the levels of stress reported by parents of intubated children were compared with those reported by parents of non-intubated children, different patterns of stress were found Painful procedures were a source of greater stress to parents of intubated children whereas the behaviour of staff and the children's reactions to the intensive care experience caused greater stress to the parents of the non-intubated children In general the findings suggest that the needs of parents of non-intubated children are being overlooked, with staff focusing more of their attention on the parents of intubated children  相似文献   
42.
Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.  相似文献   
43.
44.
Hazard assessment is a basic tool used in the evaluation and regulation of chemicals, but in spite of this there are many different interpretations of the scope and function of a hazard assessment. Starting from a discussion of the essential elements and conceptual frames involved, an attempt is made to identify the sources of uncertainty that are inherent in a hazard assessment. Problems identified include unambiguous identification of the chemical source, the routes of exposure, and the possible targets to be considered. Inadequacies in effects data are frequent, but unlike many of the other sources of uncertainty, these are often compensated for by the use of safety factors when setting quantitative limits for human or environmental exposure. The inherent uncertainties in the process make periodic revisions of any hazard assessment process inevitable, as new knowledge on routes of exposure and targets becomes available.  相似文献   
45.
The duration of the late exteroceptive suppression period (ES2) of temporal muscle EMG activity has been reported to be reduced in patients suffering from chronic tension-type headache. Methods of recording and analysing ES2 have varied between centers and reproducibility of results within subjects , although insufficiently studied, has generally been poor. ES2 was investigated in 30 healthy subjects, using a computerized technique of recording, rectifying and averaging the EMG signals. Hour to hour and week to week variations of ES2 durations were calculated, and the influence of pain during a cold pressor test and of sustained muscle contraction on ES2 durations was investigated. The intra-individual variation of ES2 durations was 16.0% from hour to hour and 20.7% from week to week. The inter-individual variation was 36.7%. The present method for analysis of ES2 periods proved to be reliable, as the intra-observer variation was 4.2% and the inter-observer variation 4.6%. ES2 periods were significantly shorter on the first compared to the second day of examination ( p = 0.006) and during experimental pain ( p = 0.0005). We recommend the use of the computerized averaging technique in future studies and caution against the dependence of results upon factors such as conditioning and pain.  相似文献   
46.
A serous retinal detachment and choroidal hemorrhagic infiltration developed in a 17-year-old girl with acute lymphoblastic leukemia one year after cessation of therapy without concurrent bone marrow (BM) or central nervous system relapse. A choroidal biopsy through a sclerotomy with simultaneous release of subretinal fluid revealed no malignant cells. Accordingly, she was treated with prednisone, topical corticosteroid and atropine with normalisation of vision and clinical findings. Five months later the retinal detachment and choroidal infiltration recurred. In order to re-attach the retina once more and obtain a representative choroidal biopsy, a pars plana vitrectomy followed by a retinotomy with removal of subretinal tissue was done revealing leukemic infiltration of the choroid. Simultaneously a BM relapse was diagnosed.  相似文献   
47.
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
48.
Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants.  相似文献   
49.
The safety and efficacy of piezoelectric extracorporeal shockwave lithotripsy in the treatment of symptomatic gallbladder stones were evaluated in 53 consecutively treated patients. All treatments were performed as outpatients without anesthesia; over 95 per cent of 109 treatments were performed without analgesia or sedation. Ursodeoxycholic acid was administered post-treatment. Seventy per cent of patients had multiple sessions. Cumulative stone-free rates of 38 per cent at 6 months, 65 per cent at 12 months, and 75 per cent at 15 months were achieved. There was no difference in eventual stone clearance between patients with single stones less than 20 mm diameter, single stones greater than or equal to 20 mm diameter, or multiple (two or three) stones, although patients with single smaller stones required significantly fewer total shocks to become stone-free (P = .02). Stone clearance correlated with estimated stone volume. Biliary pain occurred in 62 per cent of patients after treatment but ceased in stone-free patients. Biliary complications of pancreatitis (7.5%) and choledocholithiasis (3.8%) were successfully treated by endoscopic papillotomy. Nonbiliary complications were virtually nonexistent. Three patients (5.7%) had elective cholecystectomy. Results indicate that piezoelectric lithotripsy is a safe, minimally painful treatment that, in conjunction with oral bile acids, can produce stone-free rates of 75 to 100 per cent in selected patients.  相似文献   
50.
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