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1.
The percentage uptake of [123I]metaiodobenzylguanidine (MIBG) by tumors of the paraganglion system is compared with the number of neurosecretory granules (assessed by both light and electron microscopy) in the subsequently resected tumors in six patients. Iodine-123 MIBG was injected intravenously; the tumor uptake of [123I]MIBG varied between 0.001% and 0.14% of the injected dose per gram of tumor tissue at 22 hr. The number of neurosecretory granules in tissue sections was scored on a scale of I-III. A direct proportional correlation was found between the percentage uptake of [123I]MIBG by the tumor and the number of neurosecretory granules in the tissue sections but not with plasma or urinary catecholamines. This technique for imaging reflects the storage status of the tumor better than plasma and urinary catecholamine measurements.  相似文献   
2.
This study is a retrospective review of nine patients who sustained isolated fractures of the lateral process of the talus. The majority were caused by inversion or a combination of inversion and dorsiflexion of the foot. Following a review of the literature and anatomical dissections the authors recommend a classification based on anterior-posterior tomography of the talus, into intra- and extra-articular fractures.  相似文献   
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A 50-year-old patient with breast cancer was about to withdraw from her adjuvant chemotherapy regimen because of a long-standing phobia about being injected, which had been compounded by anxieties that were associated with the severe side-effects of adjuvant chemotherapy. She experienced a conditioned nausea response to hospital and medical situations. A psychological programme that incorporated relaxation training, systematic desensitization by way of the patient's visual imagination and videotape modelling, allowed her to complete the course of chemotherapy and to feel less anxious in hospital and medical settings.  相似文献   
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1. Responses to gamma-aminobutyric acid (GABA) were evoked in mouse fibroblast L-cells stably transfected with bovine, alpha 1, beta 1, gamma 2L sub-units of the GABAA receptor. Expression was stimulated via a steroid-inducible promoter system. 2. In near symmetrical intracellular and extracellular chloride concentrations, GABA evoked inward currents at negative holding potentials that reversed at +5 mV and displayed slight outward rectification. Concentration-response curves were fitted well by the logistic equation. GABA had a pEC50 = 5.1 +/- 0.1 and the curves had a slope of 1.9 +/- 0.1. 3. Responses to GABA were antagonized by bicuculline, picrotoxin and penicillin. The action of bicuculline was competitive (pA2 = 6.4) whilst the block by picrotoxin was uncompetitive and strongly agonist-dependent. 4. Benzodiazepine receptor agonists potentiated responses to 3 microM GABA. The rank order of potency was FG 8205 > flunitrazepam > zolpidem > C1218872. FG 8205 and C1218872 produced markedly lower maximal potentiations with efficacies 0.4 and 0.6 x that of flunitrazepam, respectively. The potencies of zolpidem and C1218872 observed are in agreement with the BZ1 type pharmacology of this sub-unit combination. The potentiation of GABA by flunitrazepam was antagonized by flumazenil with a Ki of 3.8 nM. 5. GABA responses were potentiated in the presence of pentobarbitone and alphaxalone. The response was also noticeably broadened by these compounds due to a decrease in the response decay rate. Concentrations of pentobarbitone of 100 microM and above evoked an inward current in the absence of GABA. Alphaxalone up to 10 microM did not evoke a direct response.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Recent studies from the United Kingdom and Sweden have demonstrated a dramatic rise in the number of people with hip fractures. It is our hypothesis that New Zealand is experiencing a similar rise in the number of hip fractures. The number of elderly people (over age 65 years) admitted to public hospitals in New Zealand over a 38-year period was reviewed. In people over age 75 years, we observed a disproportionate increase in the number of fractures compared with the increase in population. The highest risk group was women over age 85 years. Because of the differing age-specific fracture rates, the proportion of females over age 85 increased from 17% in 1950 to 40% by 1987. Through weighted regression analysis of fracture rate and population predictions, the projected number of fractures in the year 2001 and 2011 was predicted. By 2011 the number of people sustaining hip fractures will more than double. The proportion of the very elderly (85+) will increase from 40 to 65%.  相似文献   
8.
Previous research has shown that caffeine and a<15-min nap effectively and separately reduce sleepiness in drivers for I hr. In the present study, we examined in 12 sleepy individuals the treatments combined, taken during a 30-min break, prior to a longer (2 hr) continuous monotonous afternoon drive in a car simulator. Nonnap comparisons were 200 mg caffeine only and placebo. For placebo, driving incidents. Subjective and electroencephalographic measures of sleepiness all reflected a mid-afternoon peak'. This peak was significantly reduced by caffeine and eliminated by the combined treatment, which reduced incidents to 9% of placebo levels versus 34% of placebo levels for caffeine alone. Naps comprising “nonsleep dozing” were still effective.  相似文献   
9.
Features of 111 mammary carcinomas derived from breast cancer screening were compared with those of 69 carcinomas presenting 'clinically'. Screen detected cancers were smaller, had less likelihood of nodal metastases, included a higher proportion of in situ tumours and if invasive, tended to be of lower grade. Using immunohistochemical methods, the expression of c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR) and cathepsin D were compared in the two groups. A similar proportion of screened and unscreened tumours expressed c-erbB-2 oncoprotein and EGFR but expression of the oestrogen regulated protein cathepsin D was significantly more frequent in the screened group (P less than 0.05). Although a relatively small series, the results suggest a biological difference between 'screened' and 'clinical' tumours.  相似文献   
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