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991.
A simple pneumoconiosis with lamellar birefringent crystals was observed in animals dying in the San Diego Zoo. We studied 100 autopsies from 11 mammalian and eight avian species. In mammals, mild pulmonary lesions comprised crystal-laden macrophages in alveoli and lymphatics. Interstitial fibrosis was present in 20% of cases. There were no nodules. In birds, dust retention produced large granulomas around tertiary bronchi without fibrosis. Mineralogic analysis using scanning and transmission electron microscopy showed most of the crystals to be silicates. Ninety percent were complex silicates, with aluminum-potassium silicates comprising 70% of the analyzed particles. Electron and x-ray diffraction showed the silicates to be muscovite mica and its hydrothermal degradation product, ie, illite clay. This mica was also present on filtration membranes of atmospheric air samples obtained from the San Diego Zoo. The amount of dust retention was related to the animal's age, anatomic or ecologic variances, and length of stay in the San Diego Zoo. Its semidesert atmosphere is rich in silicates, which are inhaled and deposited in the lungs. Similar mica-induced lesions are found in humans living in this region or the Southwest of the USA. This simple pneumoconiosis is likely to be widespread in human populations living in desert or semidesert climates.  相似文献   
992.
Riassunto Gli AA. rilevano che l'incidenza dell'ernia hiatale nei diabetici è maggiore che nei nondiabetici e ne discutono i possibili motivi patogenetici.
Summary The authors point out that the incidence of hiatus hernia in diabetic patients is higher than in non-diabetic subjects. They discuss the possible pathogenetic mechanism.
The authors have contributed in equal measure to the research reported in this paper.  相似文献   
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996.
PURPOSE: To investigate the impact of rectum motion on dose - volume histograms of the rectum including filling and of the wall (DVH and DWH, respectively), during 3D-conformal radiotherapy (3DCRT) for localized prostate cancer. MATERIALS AND METHODS: Ten patients received a planning CT scan (CT(0)) and 11-14 CT during 3DCRT for prostate cancer (total CT scans=126). CT images were 3D matched using bony anatomy. A single observer drew the external contours of rectum and rectum wall and the CTV (prostate + seminal vesicles) on CT(0). Patients were asked to empty their rectum before every CT, as generally performed at the Institute for Cancer Research and Treatment (IRCC) before treatment delivery. Bladder was kept full by drinking 500 cm(3) of water 60 min before the scan, according to our protocol. A 4-field box 3DCRT technique was planned and dose statistics/dose - volume histograms of the rectum were calculated for each contour referred to CT(0),CT(1),...,CT(n) for each patient. Average DVHs during treatment were calculated along with their standard deviation (SD(rand)) and compared to the planned DVH. The analyses on the patient population included the assessment of systematic deviation (average difference and SD, named SD(sys)) as well as the average SD(rand) value expressing the random component of organ motion. Rectum shifts were also assessed by anterior and lateral BEV projections. RESULTS: As to the rectum, 8/10 patients showed a "better" average DVH than DVH on CT(0). Wilcoxon test showed a statistically significant reduction when correlating the difference Delta between the average DVH during therapy and planning DVH at CT(0): for instance V(70)Delta = -3.6% and p = 0.022, V(50)Delta = -5.5% and p = 0.022, D(med)Delta = -3.2 Gy and p = 0.007. Average values of DVH systematic difference (average difference between planning scan and treatment), standard deviations (SD(sys)) and average standard deviations of the random fluctuation (SD(random)) were -4.0%, 4.7% and 6.6%, respectively. Whilst the fluctuation results were slightly smaller for DWH. Volume analysis showed a slight systematic variation of the rectal volume between planning and treatment BEV. The average rectal volume during therapy was larger than at the planning CT in 8/10 patients. The systematic shifts of the rectal wall between the planning phase and the treatment were rather small, both below and above the flexure. The larger random fluctuation of the rectum shape was found to be in the cranial half (1 SD=4.4 mm). CONCLUSIONS: The practice of carefully emptying the rectum during simulation and therapy for prostate cancer, which is a safe and simple procedure, reduces the impact of organ motion on dose - volume parameters of the rectum.  相似文献   
997.
This study was designed to evaluate the activity and tolerability of irinotecan and docetaxel in patients with previously treated non-small cell lung cancer (NSCLC). Eligibility included recurrent or progressive NSCLC, previous chemotherapy, age > or = 18 years, ECOG PS < or = 2. Treatment consisted of irinotecan (160 mg/m2 i.v.), followed by docetaxel (65 mg/m2 i.v.) on day 1 of a 21-day cycle, for a maximum of 6 cycles. Forty patients were enrolled. Median age was 60 years and median ECOG PS was 1. All patients were evaluable for toxicity and 31 (78%) were evaluable for response. A total of 125 cycles was administered (median, 3; range, 1-6). Most common grade 3-4 toxicities were neutropenia (62%), neutropenic fever (22%), and diarrhea (32%). Response rate was 10%; a further 40% of patients achieved stable disease. All responses were observed in patients with ECOG PS < or = 1, age <70 years, and who had received only one prior chemotherapy regimen. Median time to progression was 2.8 months and median survival was 7.4 months. Because of significant toxicity and limited activity, further investigation of irinotecan plus docetaxel in second line NSCLC is not recommended.  相似文献   
998.
BACKGROUND: The prevalence and the clinical impact of gastric Helicobacter pylori (Hp) infection, as well as its possible correlation with Chlamydia psittaci (Cps) infection and the lymphoma regression rate produced by Hp eradicating antibiotic therapy were investigated in patients with MALT-type lymphoma of the ocular adnexa (OAL). METHODS: During staging, the presence of gastric Hp infection was assessed by gastroscopy and multiple biopsies in 31 OAL patients. Immediately after, Hp-positive patients were treated with eradicating antibiotic therapy, alone or associated with other therapies. RESULTS: Gastric Hp infection was detected in 10 (32%) patients; this feature did not correlate with patients' characteristics and disease. Four Hp-positive patients were treated with Hp-eradicating antibiotics therapy as exclusive strategy (assessable for response), none of them showed lymphoma regression. Conversely, 6 Hp-positive patients were treated with antibiotic therapy concurrently with other therapies, achieving lymphoma regression in all cases.Three Hp-positive patients with Cps-positive lymphoma were treated with doxycycline at relapse, resulting in two CR and one PR, which lasted 24+, 20+, and 18+ months, respectively. One of these patients achieved a CR after doxycycline despite the chronic persistence of Hp infection, whereas Cps-eradication was confirmed in the analysis of PBMC samples. CONCLUSIONS: Gastric Hp infection, even if common among OAL patients, does not influence clinical presentation. Hp-eradicating antibiotic therapy is not active against OAL. Cps-eradicating antibiotic therapy with doxycycline induces lymphoma remission irrespectively of the persistence of Hp infection.  相似文献   
999.
Acute toxic exposures in childhood are quite a frequent event in Paediatric Emergency Medicine. Despite that, there are few papers about clinical toxicology in children, at least in Italy. This paper is the first that takes into account both epidemiological aspects and clinical features of acute poisoning in children on a national basis. Collected data show the increased use of activated charcoal as a treatment and the use of the short stay observation unit as an appropriate answer to the real clinical situation, although some aspects are still controversial. It will be necessary to reconsider the whole matter widening the number of participating centres, so that the most controversial aspects may be clarified.  相似文献   
1000.
Schwannoma is a peripheral nerve tumour,occasionally located in the genitourinary tract.We described anextremely rare case of intratesticular neurinoma in a 79-year-old patient.(Asian J Androl 2006 Jan;8:101-103)  相似文献   
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