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排序方式: 共有1313条查询结果,搜索用时 15 毫秒
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Parviz K Amid 《Hernia》2005,9(2):201; author reply 202-201; author reply 203
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Andreas Büttner Bilge Bavbek Peter A. Winkler Parviz Mehraein Serge Weis 《Neuropathology》1997,17(2):94-100
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial. 相似文献
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Farideh Nejat Parvin Tajik Mostafa El Khashab Syed Shuja Kazmi Ghamar Taj Khotaei Shahrzad Salahesh 《Journal of microbiology, immunology, and infection》2008,41(2):112-117
BACKGROUND AND PURPOSE: Shunt infection represents a particularly morbid condition, which can also result in mortality. In order to decrease the high morbidity and mortality rates, prevention is an essential step. The purpose of this study was to compare the prophylactic use of ceftriaxone and trimethoprim-sulfamethoxazole (SXT) for the prevention of ventriculoperitoneal (VP) shunt infection. METHODS: In this prospective, single-institution, randomized clinical trial, 107 children with hydrocephalus and an indication for shunting were randomly assigned to prophylaxis with ceftriaxone (n = 50) or SXT (55), each administered as a single dose during anesthesia and two divided doses postoperatively. Patients were followed up for at least one year. RESULTS: The mean age of patients was 15 months, and 85% were aged 6 months or younger. During the first postoperative year, meningitis occurred in 13.5% of patients receiving ceftriaxone and 14.5% of the SXT group, with no statistically significant difference between the groups. Younger age, presence of cerebrospinal fluid leakage and aqueductal stenosis as a cause of hydrocephalus showed significant correlation with meningitis occurrence on univariate analysis. However, only the latter 2 factors were associated with meningitis on multivariate analysis. The risk of shunt infection did not correlate with the gender of the patient, time of VP shunt surgery, or duration of hospitalization for shunting. CONCLUSION: Ceftriaxone and SXT showed similar efficacy in preventing shunt infection. Cerebrospinal fluid leakage before or after VP shunt placement and aqueductal stenosis were independent risk factors for meningitis after VP shunt. 相似文献
7.
Martin Griebe Michael Daffertshofer Mark Stroick Magdalena Syren Parviz Ahmad-Nejad Michael Neumaier Juergen Backhaus Michael G. Hennerici Marc Fatar 《Neuroscience letters》2007
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool. 相似文献
8.
Echocardiographically documented mitral-valve prolapse. Long-term follow-up of 237 patients 总被引:5,自引:0,他引:5
R A Nishimura M D McGoon C Shub F A Miller D M Ilstrup A J Tajik 《The New England journal of medicine》1985,313(21):1305-1309
We determined the long-term prognosis for patients with mitral-valve prolapse documented by echocardiography by following 237 minimally symptomatic or asymptomatic patients for a mean of 6.2 years (range, 1 to 10.4). The actuarial eight-year probability of survival was 88 per cent, which is not significantly different from that for a matched control population. An initial left ventricular diastolic dimension exceeding 60 mm was the best echocardiographic predictor of the subsequent need for mitral-valve replacement (17 patients). Of the 97 patients with redundant mitral-valve leaflets identified echocardiographically, 10 (10.3 per cent) had sudden death, infective endocarditis, or a cerebral embolic event; in contrast, of the 140 patients with nonredundant valves, only 1 (0.7 per cent) had such complications (P less than 0.001). Most patients with echocardiographic evidence of mitral-valve prolapse have a benign course, but subsets at high risk for the development of progressive mitral regurgitation, sudden death, cerebral embolic events, or infective endocarditis can be identified by echocardiography. 相似文献
9.
Birt Diane F.; Pelling Jill C.; Pour Parviz M.; Tibbels Michelle G.; Schweickert Lori; Bresnick Edward 《Carcinogenesis》1987,8(7):913-917
Studies were conduded to evaluate the ability of dietary driedcabbage supplements to inhibit pancreatic carcinogenesis inhamsters and skin tumorigenesis in mice. Pancreatic cancer wasinduced by treatment with 40 mg/kg body wt N-nitrosobis-(2oxopropyl)amine(BOP). Cabbage was fed from before carcinogen treatment in lowfat diet and, beginning 1 week after BOP treatment, cabbagewas given in low fat and high fat diets in comparison with therespective non-cabbage containing diets. Dried cabbage was incorporatedat 9 and 11% levels into the low and high fat diets. Feedingcabbage in the high fat diet elevated the yield of BOP-inducedpancreatic ductular cardnoma (1.6 carcinomas/effedive animal)in comparison with that observed in hamsters fed cabbage ina low fat diet or in those given a high fat diet without cabbage, 0.60.8 carcinomaa/effedive animal (P 0.05). Furthermore,the incidence of BOP-induced gall bladder adenocadnomm was elevatedin cabbage-fed hamsters irrespedve of dietary fat intake. Effetsof dietary fat and cabbage on food consumption, body weight,and serum T3 and T4 values are described. Skin tumorigenesiswas induced in SENCAR mice by 10 nmd 7,12 dlmethylbenz[a]anthracene(DMBA) and promoted beginning 1 week later with twice weeklyapplications of 2 µg 12-O-tetradecanoyl-13-phorbol acetate(TPA). Dried cabbage was incorporated into AIN semi-purifieddiets from before DMBA treatment and throughout TPA treatment.Skin papilloma yield was elevated in DMBA-initiated TPA-promotedmice that were fed diets containing 10% cabbage. Mice fed cabbagedeveloped an average of 8.45 papillomas per mouse following22 weeks of promotion while mice given control diet developed7.25 papillomas per mouse (P < 0.001). Cabbage feeding didnot influence survival, food consumption or body weight of themice. These results suggest the need for further research onthe use of cabbage as a chemopreventive measure. 相似文献
10.
Parviz Ghadirian PhD Bryna Shatenstein Maurice Verdy Pavel Hamet 《European journal of epidemiology》1995,11(3):275-281
Elevated levels of plasma uric acid have been linked to increased risk of cardiovascular diseases and their complications. As dairy proteins have been found to decrease plasma uric acid without increasing glomerular filtration rate, a sample of postmenopausal women living in Montreal was studied to investigate the nature of this relationship. Participants (158 Roman Catholic nuns) were randomly assigned to one of two test diets for a period of four weeks: the dairy foods group (n=81) consumed approximately 30 grams of dairy protein daily and the dairy-free diet group (n=77) ate no dairy foods at all. Subjects completed two one-day food records, a core questionnaire and a dairy foods diet history; blood specimens were obtained, and blood pressure, height and weight were measured. Average nutrient intakes differed as a consequence of the test diets, with significantly greater intakes of protein, fat, saturated fat, monounsaturated fat, potassium and calcium (p<0.01) in the dairy group after the study period, and lower dietary levels of protein, cholesterol, calcium and retinol (p<0.01) in the dairy-free group. Plasma uric acid was unchanged after the dietary intervention in the dairy group, but increased by 7.8 µmol/1 (p=0.03) in subjects on the dairy-free diet; however, diastolic blood pressure decreased in response to calcium (=–22.9, SE=10.0,p=0.02) among those whose diet included dairy foods. The study results suggest that proteins of dairy origin may play a role in stabilising or lowering plasma uric acid, and that calcium or other components found in milk products may also reduce diastolic blood pressure. While these findings have implications for dietary prevention to decrease cardiovascular risk in postmenopausal women, further investigations should examine these mechanisms in men over the age of 50 to ascertain whether a similar response would occur. 相似文献