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排序方式: 共有1992条查询结果,搜索用时 15 毫秒
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Computed tomography is currently the modality of choice in imaging acutely traumatized patients. This is based upon CT's documented ability to detect surgically significant lesions. Furthermore, the use of MRI is limited by a lack of bone detail, the degradation of MR images in frequently uncooperative patients, and a limited supply of nonferromagnetic monitoring equipments. CT and MRI are largely equivalent in their ability to diagnose epidural hematoma, but CT is readily available and quick. MRI provides information in addition to that obtained by CT in many instances, such as subacute and chronic subdural hematomas, contusions, and intracerebral hematomas. 相似文献
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MR imaging of neurocysticercosis 总被引:1,自引:0,他引:1
C S Zee H D Segall W Boswell J Ahmadi M Nelson P Colletti 《Journal of computer assisted tomography》1988,12(6):927-934
Magnetic resonance (MR) was performed in 50 patients with neurocysticercosis. Comparison was made with other neuroradiological imaging modalities including CT, myelography, CT ventriculography, and CT myelocisternography. Eighteen patients were found to have intraventricular cysts. In several patients, these were multiple and 22 intraventricular cysts were discovered. Although 4 of the 22 ventricular cysts were missed by MR, T1-weighted images can play a significant role in the early detection of intraventricular cysticercosis cysts, showing the cyst wall (9 of 22), a high intensity mural nodule (6 of 22), and increased signal intensity of the cyst fluid (5 of 22). Cisternal cysts (14 cysts in 10 patients) could be identified; they appear similar to intraventricular cysts, but mural nodules are infrequently seen (1 of 14). Twenty-nine patients had 69 parenchymal cysts. An attempt was made to assess the viability of these parenchymal lesions by matching the CT and MR findings with the Escobar pathologic staging system. Neuroimaging findings seemed compatible with early parenchymal lesions in the vesicular stage in 11 instances. Findings in cases with later stage cysts tend to support the concept that a dying larva provokes pronounced inflammatory reaction in the adjacent brain. Computed tomography remains the superior modality for depicting parenchymal calcifications within dead larvae. A case of a spinal cysticercosis cyst demonstrated with MR (in a patient with extensive intracranial cisternal cysts and a fourth ventricular cyst) is described. 相似文献
5.
Markus Golling Cosima Jahnke Hamidreza Fonouni Rezvan Ahmadi Renate Urbaschek Raoul Breitkreutz Peter Schemmer Thomas W Kraus Martha M Gebhard Markus W Büchler Arianeb Mehrabi 《Liver transplantation》2007,13(4):607-617
The liver function and perfusion following brain death is mainly influenced by the sympathetic nerves and hormones. We examined the specific influence of surgical liver denervation on systemic and hepatic perfusion parameters, bowel ischemia and oxidative stress in hemodynamically stable BD and control (living donor [LD]) pigs. Brain death was induced in 8 pigs via saline infusion into the balloon of an epidural Tieman-catheter (1 mL/15 minutes) and compared to the control group (n = 6) over 4 hours. At 2 hours postoperatively, complete liver denervation was initiated. We analyzed systemic cardiocirculatory parameters (mean arterial pressure, aortic flow, bowel ischemia (endotoxin, and endotoxin-neutralizing capacity) and oxidative stress (total glutathione in erythrocytes [tGSH(E)]) and compared them to local/hepatic perfusion parameters (hepatic artery and portal venous flow, liver blood flow index, and microperfusion), local bowel ischemia (intramucosal pH [pHi] of stomach [pHi(S)]/colon[pHi(C)]), and liver oxidative stress (glutathione [rGSH(L), GSSG(L)]). Following brain death, the parameters including mean arterial pressure, aortic flow, pHi, endotoxin, and tGSH(E) showed no significant changes at 2 hours. Portal venous flow and microperfusion were decreased significantly and hepatic arterial buffer response was ineffective. Hepatic oxidative stress was increased in BD animals (decrease rGSH(L), increase GSSG(L)). Surgical denervation/manipulation increased portal venous flow significantly, hepatic arterial buffer response became effective, and stomach pHi decreased (BD and LD groups). Hepatic oxidative stress was reduced in the BD group (increase rGSH(L)/GSSG(L); P < 0.001) while it was increased in the LD group (decrease rGSH(L)/GSSG(L); P < 0.001). In conclusion, denervation reduces hepatic oxidative stress in BD only in contrast to the LD. The reciprocal effect of denervation depends on the state of neural activation and postulates a potential benefit of surgical denervation before organ harvesting in brain death. 相似文献
6.
M.R. Ahmadi A. Khodakaram Tafti S. Nazifi H.R. Ghaisari 《Comparative clinical pathology》2005,14(2):90-94
Reproductive tract abnormalities especially in the uterus and ovaries of cows often results in infertility. The object of this study was to determine the relationship between the cytology of uterine and cervical mucosa and endometrial histopathology in normal and endometritic cows. In this study, the genital tracts of 131 slaughtered cows were collected. According to macroscopic appearances and histopathological evaluation, reproductive tracts were divided into normal and abnormal. Cytological samples were obtained from the discharges of cervical mucosa and uterine fluid that were collected by wet cotton swab and gentle aspiration. Differential cellular counts were carried on Giemsa stained smears of the mucosa. Comparison of cell densities of normal cows with endometritic cows showed significant differences (P<0.05) in the macrophage presence both by swab (0.00±0.00) and aspiration (0.16±0.55) methods. Comparison of cell densities in different grades of endometritis showed a significant difference (P<0.05) in the neutrophil percentage in cervical mucosa between the swabbing and aspiration methods. In this study, there were no significant differences in cell densities between the two collection methods in cows affected with either acute or chronic endometritis. However, there was significant difference in the neutrophil density in aspirated cervical mucosa compared to the swab collection in cows affected with subacute endometritis. Cytological methods can be useful for the diagnosis of clinical and subclinical endometritis of cows. 相似文献
7.
Pharmacological characterisation of a new potent and specific nonpolypeptidic cholecystokinin antagonist 总被引:5,自引:0,他引:5
I Setnikar M Bani R Cereda R Chisté F Makovec M A Pacini L Revel L C Rovati L A Rovati 《Arzneimittel-Forschung》1987,37(6):703-707
D,L-4-(3,4-Dichloro-benzoylamino)-5-(N-3-methoxypropyl- pentylamino)-5-oxo-pentanoic acid (CR 1505) belongs to a newly discovered class of agents with cholecystokinin (CCK) antagonistic activity. CR 1505 displaces CCK-8 from the central CCK receptors at concentrations of 9.1 mumol/l, and from the peripheral CCK receptors at concentrations of 0.33 mumol/l. CR 1505 antagonizes in vitro the contractant effects of CCK-8 on gall bladder strips of the guinea pig at 0.79 mumol/l and those on the small intestine at 1.6 mumol/l. These antagonistic effects are dose dependent and of competitive type. The antagonistic activities of CR 1505 against contractions of smooth muscles elicited by CCK-8 are at least 1000 times more potent than those against the contractions elicited by acetylcholine, BaCl2, histamine, serotonin, Substance P, bradykinin or dimethylphenylpiperazine. CR 1505 is also practically ineffective against the contractions of the small intestine of the guinea pig elicited by electrical field stimulations either as "cholinergic twich" (0.05 Hz), or as "cholinergic contractions" (trains of 10 min at 1 Hz), or as "non-cholinergic contractions" (200 impulses at 5 Hz in presence of atropine). CR 1505 is therefore a potent, specific, competitive and reversible CCK antagonist. 相似文献
8.
E Dejana I Martin-Padura D Lauri S Bernasconi M R Bani A Garofalo R Giavazzi J Magnani A Mantovani S Menard 《Laboratory investigation; a journal of technical methods and pathology》1992,66(3):324-330
Endothelial leukocyte adhesion molecule-1 (ELAM-1) has been determined to be the mediator of adhesion of colon carcinoma cells to interleukin-1 (IL-1)-activated endothelial cells. To identify ELAM-1 ligand in colon carcinoma cells, we have screened a series of 11 monoclonal antibodies directed to these cells and found that only one MBr8 was able to inhibit the IL-1-induced increment in adhesion of HT29 and of SW948 colon carcinoma lines to endothelial cells. In contrast, MBr8 did not bind to polymorphonuclear cells, monocytes, and lymphocytes and did not inhibit polymorphonuclear adhesion to IL-1-activated endothelial cells. As expected, an ELAM-1 monoclonal antibody strongly inhibited IL-1 induced increment of adhesion of HT29, SW948, and polymorphonuclear cells. As negative control, MG63 osteosarcoma cells were used. These cells adhere more efficiently to IL-1 activated endothelial cells but MBr8 and ELAM-1 monoclonal antibodies did not affect their adhesion. The effect of MBr8 was also tested in an experimental system in vivo. As described previously, radiolabeled HT29 cell retention in the lung of nude mice was increased in animals given IL-1. MBr8 administration to nude mice or pretreatment of tumor cells with it inhibited this effect. These data suggest that cell adhesion to ELAM-1 might be mediated by different, cell type specific, sugar ligands. 相似文献
9.
Preservation of hypervascularity in hepatocellular carcinoma after effective proton-beam radiotherapy--CT observation 总被引:1,自引:0,他引:1
AIM: The aim of this study was to describe persistence of hypervascularity in proton treated hepatocellular carcinoma at serial follow-up computed tomography (CT). METHODS: Four patients with unresectable solitary hypervascular hepatocellular carcinoma underwent 55-82 Gy proton-beam irradiation for a period of 15-47 days. Follow-up CT including plain, enhanced and dynamic imaging was performed for a period of 9-36 months. RESULTS: Good preservation of arterial blood supply while gradual decrease in tumour size was clearly depicted by dynamic CT. CONCLUSION: We believe that preservation of hypervascularity as judged by enhancement at CT and magnetic resonance imaging, does not necessarily mean that radiotherapy in hypervascular malignant tumours has been unsuccessful. 相似文献
10.
This study provides data about the extent of alcohol use disorders among general adult psychiatric inpatients. The accuracy of alcohol use disorder diagnoses given by the lay-administered Diagnostic Interview Schedule (DIS) and by staff psychiatrists, as compared to each other, was investigated. From consecutive admissions to a private psychiatric hospital, 55 patients with alcohol use disorders were identified by trained research assistants using the DIS (n = 162). A comparison of DIS diagnoses to clinicians' diagnoses revealed that 66 patients (40.7% of all admissions) were given an alcohol diagnosis by the DIS or clinician, 35 patients (21.6%) by DIS and clinician, 20 (12.3%) by DIS only, and 11 (6.8%) by clinician only. The two diagnostic approaches were also compared using several accuracy measures (sensitivity and specificity ratios, percentage of agreement, and kappa). With psychiatrists' diagnoses as reference, the DIS sensitivity ratio was 76 and specificity ratio 83. There were 12.3% false positive and 6.8% false negative diagnoses assigned by the DIS. Kappa was .56 and percentage of agreement 80.9%. Recomputing accuracy measures for the psychiatrist, using the DIS as the reference, clinician assessment sensitivity was 64 and specificity 90. Compared to each other, the DIS "overdiagnosed" and the staff psychiatrists "underdiagnosed" by about 1 in 20 cases. Among those alcohol use diagnoses upon which both clinician and DIS agreed, alcohol abuse was the predominant diagnosis. Among all patients with an alcohol diagnosis, the main nonsubstance abuse diagnoses (as assigned by the clinician) were: major depressive, dysthymic, bipolar, schizophrenic, and personality disorders. 相似文献