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41.
18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour.  相似文献   
42.
Objective: The management of chronic vulvovaginal pain, not explicable on specific histologic grounds, presents a major problem in referral centers for lower genital tract diseases.Study design: This article reports on a two-step protocol in a sample of 175 medical nonresponders, drawn from a 2-year cohort of 725 women with vulvovaginal pain. The first maneuver was the use of a flashlamp-excited dye laser to selectively photocoagulate symptomatic subepithelial blood vessels in 168 women; the second was the microsurgical removal of chronically painful Bartholin's glands in 52 women not responsive or not suited to flashlamp-excited dye laser photothermolysis.Results: Dye laser response rates werer independent of whether patients manifested macroscopic focl of painful erythema (“vestibular adenitis”) or just colposcopically apparent hyperemia-ectasia of the individual blood vessels (“pruritic papillomatosis”) (55% vs 45% after a single surgical procedure; 76% vs 65% after serial retreatment; p not significant). Conversely, response rates were much lower among women in whom pressure on the Bartholin's glands produced sharp, lancinating pain (15% vs 66% after a single surgical procedure; 22% vs 93% after serial retreatment; p < 0.001). Forty-two (85%) of 50 patients with flashlamp-excited dye laser failure had deep pain; however, the impasse to progress was broken by gland removal. Final response rates were 92.5% (complete response 62%; partial response 30%) in the “surface-only” group and 80.3% in the “surface-plus-deep” group (χ2 = 14.9; p < 0.001). The major complication was acute bacterial cellulitis, occurring in the first postoperative week. Modification of the treatment protocol to include topical antibiotics with an occlusive dressing reduced the cellulitis rate from 17.2% to 2.5%. In four women (1.8%) Koebner-like exophytic condylomas also developed within 1 month of flashlamp-excited dye laser surgery.Conclusion: The availability of a safe, efficacious, and relatively noninvasive treatment should reduce the need for resective surgery in most patients with idiopathic vulvodynia. 1995; 172; 1684–1701.)  相似文献   
43.
We conducted a 56-day sub-chronic test on the effects of Cu on rainbow trout (Oncorhynchus mykiss) fry at a nominal water hardness of 100 mg l(-1) (as CaCO(3)). Response measures were growth, whole body Cu concentrations, and mortality. Significant mortality was observed in fish exposed to 54.1 microg Cu l(-1) (47.8%) and 35.7 microg Cu l(-1) (11.7%). Growth was dose-dependent over the range of Cu treatments (0-54 microg Cu l(-1)), and was modeled as a function of Cu exposure concentration and exposure duration. Calculated inhibition concentrations (based on change in wet weight through a 56-day Cu exposure) were IC(50)=54.0 microg Cu l(-1), IC(20)=21.6 microg Cu l(-1), IC(10)=10.8 microg Cu l(-1), and IC(01)=1.1 microg Cu l(-1). Measured whole body Cu was also dose-dependent, and growth of trout fry was readily modeled as a function of tissue Cu and exposure duration. This model was virtually identical to a model previously developed for rainbow trout exposed to Cu at a hardness of 25 mg l(-1). Following the 56-day exposure period, we performed a 96-h acute challenge to Cu and Cd to evaluate the effects of Cu acclimation on acute Cu and Cd toxicity. Sensitivity to Cu was dependent on the 'acclimation dose'; trout previously held in control aquaria (i.e. not acclimated to Cu) suffered over 80% mortality, whereas trout previously exposed to 35.7 microg Cu l(-1) for 56 day suffered 20% mortality. These fish also showed somewhat reduced sensitivity to Cd, suggesting acclimation to Cu can enhance tolerance to other metals. Finally, the relationship between growth response and hardness (derived from several studies) appeared to have a different slope than the hardness relationship previously observed for lethality responses.  相似文献   
44.
We present the study of colour duplex Doppler ultrasonography on Indian patients with non‐vasculogenic erectile dysfunction. Patients with a history suggestive of psychogenic impotence along with a normal clinical response to intracavernosal papaverine were presumed to have non‐vasculogenic erectile dysfunction. In our patients, the incidence of psychogenic impotence was much higher and the mean age of patients presenting with erectile dysfunction was lower as compared to patients from developed countries reported in research. The Doppler flowmetry showed much higher mean peak systolic velocities (PSVs) with a negative correlation between age and PSV. End diastolic velocity, resistive index and acceleration time values conformed to the literature.  相似文献   
45.
Paternal participation in postpartal activities may enhance the formation of affectional bonds between the father and the newborn. The father's expression of love, warmth, and compassion for his infant have often been inhibited by a heretofore limited definition of the paternal role by certain socioeconomic events and by gaps in our implementation of family-centered maternity care. Research is needed to investigate paternal needs postpartally and to identify alternatives that nursing can provide to best fulfill these needs. The focus of family-centered maternity care must be broadened in order to more directly reject the needs of the father.  相似文献   
46.

Background  

The early to intermediate stages of the majority of colorectal tumours are thought to be driven by aberrations in the Wnt (APC, CTNNB1) and Ras (K-ras) pathways. A smaller proportion of cancers shows mismatch repair deficiency. The aim of this study was to analyse the co-occurrence of these genetic alterations in relation to tumour and patient characteristics.  相似文献   
47.
BACKGROUND: Mechanical manipulation, pressure, and temperature increase can induce bone necrosis during intramedullary reaming. METHODS: In this study, the bone debris obtained after reaming 18 sheep tibiae was analyzed to investigate its vitality by measuring alkaline phosphatase activity. Two different reamer designs were used for the project. Bone cells were first cultivated in a specific growth medium, counted 3 weeks after the reaming procedure, and then cultivated for another 5 weeks. RESULTS: At the end of the project, qualitative evaluation showed positive alkaline phosphatase activity in most of the cases, and quantitative evaluation also showed enzyme activity. The positive alkaline phosphatase results were independent of the reamer sizes and reamer design. No significant results were obtained from a comparison of different reamer sizes and designs. This indicates that osteoblasts survive after correctly performed reaming. CONCLUSION: The results prove the vitality of the bone debris and confirm clinical observations.  相似文献   
48.
OBJECTIVE: Myocardial ischemia and reperfusion induced by cardioplegic arrest subjects the heart to free radical-mediated stress. The purpose of our study was to investigate the effect of cardioplegia-induced ischemia and reperfusion on myocardial formation and distribution of (1) nitrotyrosine as an indicator for peroxynitrite-mediated tissue injury resulting from increased nitric oxide release and (2) 8-isoprostane as an indicator for oxygen-derived free radical-mediated lipid peroxidation. METHODS: In 10 patients undergoing coronary artery operations (64 +/- 6 [mean +/- SD] years, 3 women and 7 men) subjected to cardiopulmonary bypass and intermittent cold blood cardioplegia, we collected transmural left ventricular biopsy specimens before and at the end of cardiopulmonary bypass. Specimens were cut at 10 micro m and subjected to immunocytochemical staining against the nitric oxide-producing enzyme constitutive nitric oxide synthase, cyclic guanosine monophosphate (intracellular second messenger of nitric oxide), nitrotyrosine, and 8-isoprostane by using polyclonal antibodies. For global left ventricular function determination, we measured the fractional area of contraction using transesophageal echocardiography. RESULTS: Nitric oxide synthase activity in cardiac myocytes increased from 34 +/- 10 gray units before cardiopulmonary bypass to 47 +/- 12 gray units at the end of bypass (P =.015), and all hearts showed increased cyclic guanosine monophosphate content in both myocytes and endothelial cells at the end of bypass. The number of nitrotyrosine-positive capillaries increased from 36 +/- 29/mm(2) before bypass to 82 +/- 47/mm(2) at the end of bypass (P =.012), and 8-isoprostane-positive capillaries increased from 92 +/- 72/mm(2) before bypass to 209 +/- 108/mm(2) at the end of bypass (P =.005). The fractional area of contraction was 53% +/- 12% before bypass and 56% +/- 12% after bypass (P =.47) but was slightly decreased to 45% +/- 14% at 4 hours after bypass (P =.121). CONCLUSIONS: Our data show that cardioplegia-induced myocardial ischemia and reperfusion is associated with nitrotyrosine and 8-isoprostane formation mainly in the coronary endothelium, indicating injury mediated by both peroxynitrite and oxygen-derived free radicals. Because nitric oxide synthase activation was accompanied with increased cyclic guanosine monophosphate, these data suggest that direct effects of nitric oxide on cardiac myocytes, as well as nitric oxide-mediated coronary endothelial injury, might contribute to injury associated with cardioplegia and cardiopulmonary bypass.  相似文献   
49.
Twenty-one children who had been diagnosed as having laryngomalacia by direct laryngoscopy in infancy were reviewed 7 to 12 years later. The natural history of the disease is documented. A wide variation in the time of onset and duration of the stridor was found and there was a high incidence of feeding difficulties. A previously reported association with mental retardation or cerebral palsy is not confirmed. 4 out of the 21 children had early speech problems.  相似文献   
50.
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