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11.
Extranodal lymphomas presenting as soft tissue sarcomas to a sarcoma service over a two-year period.
J K O'Neill V Devaraj D A T Silver P Sarsfield C A Stone 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(6):646-654
Non-Hodgkin's lymphoma usually presents with lymphadenopathy at multiple sites but can also involve any part of the musculoskeletal system. Occasionally the presentation is with a soft tissue mass. The presentation of large, superficial lymphomatous masses is similar both clinically and radiologically to that of soft tissue sarcomas. The six cases of lymphoma presenting to the Exeter Sarcoma Service as suspected soft tissue sarcomas, over a two-year period (2002-2004), are presented. We describe the clinical and imaging characteristics of these tumours and their subsequent management. Our cases showed variability in presentation. Only one of the six cases presented with pain and one with tenderness. Four of the cases had no lymphadenopathy and the other two had lymphadenopathy restricted to one nodal basin. Overlying soft tissue swelling occurred in four cases and in distal limb swelling beyond the mass in one case. Radiologically, lymphomas are known to be likely to exhibit confluent lymphadenopathy that is rare in patients with soft tissue sarcoma. Confluent lymphadenopathy was demonstrated in only one case of this series of patients. It is thought that lymphomas infiltrate across anatomical fascial planes more readily than sarcomas and in four of our six cases this feature was present. Clinical history, examination and MRI are insufficient to differentiate between soft tissue sarcoma and lymphoma and the importance of obtaining a pathological diagnosis prior to surgery is clear. It is crucial to differentiate lymphoma from sarcoma in order to avoid unnecessary excisional procedures in lymphoma patients. 相似文献
12.
Defenses of the hamster lung against human neutrophil and porcine pancreatic elastase 总被引:2,自引:0,他引:2
P J Stone E C Lucey J D Calore M P McMahon G L Snider C Franzblau 《Respiration; international review of thoracic diseases》1988,54(1):1-15
Instillation of human neutrophil elastase (HNE) into hamster lungs produces milder emphysema but more pulmonary hemorrhage than an equivalent amount of porcine pancreatic elastase (PPE), whether equivalence is determined by elastolytic units or moles. We undertook a study of the mechanisms of these differences. 125I-HNE or 3H-PPE were instilled intratracheally into hamsters. The partitioning of radioactivity between bronchoalveolar lavage fluid (BAL) and lung tissue was similar for HNE and PPE as were the half-lives, 45 and 51 min, respectively, for uncomplexed, enzymatically active HNE and PPE. In BAL there was preferential binding and inactivation of HNE by the hamsters' alpha-1-protease inhibitor (a-1-PI) whereas PPE was preferentially bound by alpha-2-macroglobulin (a-2-M). This was also observed in vitro when HNE and PPE were incubated with plasma from untreated hamsters. Nevertheless, when the sum of the elastase binding capacity of a-1-PI and a-2-M was considered, hamster plasma had similar binding capacities for HNE and PPE. It is known that the enzymatic activity of elastases is inhibited by formation of a stable complex with a-1-PI. On the other hand, elastases bound to a-2-M are protected against a-1-PI inhibition but can free themselves by proteolysis and exhibit elastolytic activity. Preferential inactivation of HNE by a-1-PI may be one mechanism that accounts for the lesser emphysema-inducing potency of HNE than of PPE. 相似文献
13.
When administered systemically, glucose attenuates deficits in memory produced by several classes of drugs, including cholinergic antagonists and opiate agonists. Glucose also enhances memory in aged rats, mice, and humans. In addition, glucose ameliorates age-related reductions in paradoxical sleep. Because deficits in paradoxical sleep are most marked in those individual aged rats that also have deficits in memory, treatments which improve one of these functions may similarly improve the other. The present experiments show that glucose attenuates deficits in paradoxical sleep and memory after atropine administration, with similar dose-response curves for both actions. In the first experiment, rats received saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100, 250, and 500 mg/kg) 30 min before assessment on a spontaneous alternation task. In the second experiment, 3-h EEGs were assessed for spontaneous daytime sleep in rats administered saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100 and 250 mg/kg). In both experiments, glucose significantly attenuated deficits at an optimal dose of 100 mg/kg. A third experiment assessed blood glucose levels after injections of atropine + glucose (100 mg/kg) and determined that blood glucose levels were similar to those produced by other treatments which enhance memory. These results are consistent with the view that paradoxical sleep and at least one test of memory are similarly influenced by atropine and glucose. 相似文献
14.
Tracheal intubation is a skill that should be considered supplementary to other aspects of airway management which are of vital importance in resuscitation. Doctors involved in resuscitation should develop and retain such skills, and be aware of potential dangers. 相似文献
15.
Autosomal dominant neovascular inflammatory vitreoretinopathy 总被引:1,自引:0,他引:1
S R Bennett J C Folk A E Kimura S R Russell E M Stone E M Raphtis 《Ophthalmology》1990,97(9):1125-35; discussion 1135-6
Twenty-eight of 61 members of a six-generation family are affected by an autosomal dominant eye disease which has not been described previously. Affected patients are asymptomatic in early adulthood, but have vitreous cells and the selective loss of the b-wave on the electroretinogram. Later, peripheral retinal scarring and pigmentation, peripheral arteriolar closure, and neovascularization of the peripheral retina at the ora serrata or occasionally neovascularization of the optic disc develop. Cystoid macular edema, vitreous hemorrhage, tractional retinal detachment, and neovascular glaucoma can cause profound visual loss. Vitrectomy reduces traction on the retina and allows for retinal reattachment. The role of argon laser photocoagulation or cryopexy in reducing the neovascular complications remains uncertain. 相似文献
16.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
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19.
Direct excitatory effects of neuropeptide Y (NPY) on rat hippocampal neurones in vitro 总被引:3,自引:0,他引:3
Intracellular recordings from granule cells of the rat dentate gyrus show neuropeptide Y (NPY) applied by pressure ejection from pipettes containing 1.2-12 microM by pressures of less than 200 kPa for 1-5 s in duration to consistently evoke membrane depolarisations accompanied by a reduction in membrane resistance. The depolarisations were accompanied by an increase in excitability. Since the depolarisations evoked by NPY were not attenuated by either tetrodotoxin or kynurenic acid a direct excitatory action of NPY is postulated. 相似文献
20.
B O Cheng R P Trimble R J Illman B A Stone D L Topping 《The British journal of nutrition》1987,57(1):69-76
Adult male rats were fed on diets containing 100 g dietary fibre/kg either as alpha-cellulose or wheat bran or the pericarp-seed coat or aleurone layers prepared from that bran by sequential milling and air elutriation and electrostatic separation. After 10 d, concentrations of total volatile fatty acids (VFA) in caecal fluid were significantly different between groups and fell in the order: aleurone greater than wheat bran greater than pericarp-seed coat greater than cellulose. This ranking probably reflected the ease of fermentation of fibre polysaccharides by colonic bacteria which also resulted in a considerably higher faecal bacterial mass in the aleurone group. Because of the differences in the volume of caecal digesta, the mass of caecal VFA was considerably the highest in the aleurone group, intermediate with wheat bran and equally low in the pericarp-seed coat and cellulose groups. The diet based on aleurone gave a relatively higher proportion of propionate but with both pericarp-seed coat and wheat bran the contribution of butyrate was raised. VFA concentrations in hepatic portal venous plasma were proportional to caecal concentrations with very high (greater than 3 mM) values being recorded in the aleurone group. The findings are discussed in relation to the apparent susceptibility of the morphological components of wheat bran to fermentation by large bowel bacteria. 相似文献