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991.
White RP Deane C Hindley C Bloomfield PM Cunningham VJ Vallance P Brooks DJ Markus HS 《Journal of the neurological sciences》2000,178(1):23-28
Despite their potential use as cerebral vasodilatory agents there are few studies of the effect of nitric oxide (NO) donors on the cerebral circulation in non-anaesthetised man. We determined the effect of the NO donor glyceryl trinitrate (GTN) at clinically relevant doses on global and regional cerebral blood flow (CBF) in healthy non-anaesthetised volunteers, using H(2)(15)O PET, ultrasonic colour velocity flow imaging of carotid artery flow, and transcranial Doppler (TCD) of middle cerebral artery velocities (MCAv). Three rates of GTN infusion (0.1, 0.4, 1.0 microg/kg/min) were used. There was no significant change in common or internal carotid artery flow following GTN administration although a dose dependent fall in MCAv post GTN was observed. There was no significant change in either global or regional CBF following GTN. Thus intravenous GTN at therapeutic doses in awake humans does not alter global or regional CBF. However it does produce basal cerebral artery vasodilatation as evidenced by a fall in MCAv in the absence of a change in internal carotid artery flow. 相似文献
992.
Preoperative Evaluation of Pancreatic Masses with Positron Emission Tomography Using 18F-fluorodeoxyglucose: Diagnostic Limitations 总被引:7,自引:0,他引:7
Sendler A Avril N Helmberger H Stollfuss J Weber W Bengel F Schwaiger M Roder JD Siewert JR 《World journal of surgery》2000,24(9):1121-1129
Identification of pancreatic cancer in patients presenting with an enlarged pancreatic mass is a major diagnostic problem.
Positron emission tomography (PET) using the radiolabeled glucose analogue 18F-fluorodeoxyglucose (FDG) has been suggested to provide excellent accuracy for noninvasive determination of suspicious pancreatic
masses. We conducted a prospective study to verify these results. Forty-two patients admitted for pancreatic surgery underwent
PET scanning. Image analysis was based on visual film evaluation and quantification of regional tracer uptake. PET imaging
was visually analyzed by three observers blinded for the results of other diagnostic tests; they qualitatively graded the
scans using a five-point scale (I = low to V = high) for the presence and intensity of focal FDG uptake. Diagnosis was proven
by histology (n= 38) or follow-up (n= 4). Furthermore, the results of PET were compared with helical computed tomography (CT) and conventional ultrasonography
(US), done during the routine diagnostic workup before pancreatic cancer surgery. Regarding only the results with scores of
IV and V as positive for representing definite malignancy yielded a sensitivity of 71% and a specificity of 64% for film reading.
Quantification of regional tracer uptake contributed no significant diagnostic advantage for differentiation between benign
and malignant tumors. Helical CT revealed a sensitivity of 74% and a specificity of 45.5% and abdominal US 56% and 50%, respectively.
We concluded that PET imaging provides only fair diagnostic accuracy (69%) for characterizing enlarged pancreatic masses.
PET does not allow exclusion of malignant tumors. In doubtful cases, the method must be combined with other imaging modalities,
such as helical CT. The results indicate that the number of invasive procedures is not significantly reduced by PET imaging. 相似文献
993.
Judy Mae Pascasio Susan Hammond Stephen J. Qualman 《Pediatric and developmental pathology》2003,6(3):209-214
The role of gastric biopsy in the diagnosis of Crohn disease (CD) in the pediatric population has not been well described. We assessed the use of gastric biopsies in the diagnosis of CD using specific histopathologic parameters: granulomata, focal gland injury with neutrophils (glandulitis or glandular abscesses), and/or focal concomitant eosinophilic infiltrates. Multiple (438) consecutive pediatric biopsies with inflammation spanning a 5-year period were identified from archival material in patients ages 2 months to 16 years. A total of 56 CD cases were confirmed using colon biopsies and clinical and radiologic data as the gold standards of diagnosis. Review of hematoxylin and eosin (H&E) slides and Diff-Quik stained slides (negative for Helicobacter pylori) isolated 53 cases which suggested CD on gastric biopsy: 20 cases with granulomata, 14 cases with focal glandulitis and glandular abscesses, and 19 cases of focal glandulitis/glandular abscesses with eosinophilic infiltrates. Seventy-seven percent (43/56) were correctly identified as patients with CD. Twenty-three percent (13/56) of CD cases were not identified primarily because of concurrent H. pylori infection identified on Diff-Quik stain with a superimposed nonspecific diffuse gastritis. The use of Diff-Quik stain to identify H. pylori cases after all other factors are considered was significant (P = 0.0145); a negative stain, combined with the identified histopathologic features indicative of CD, significantly increased the accuracy of CD diagnosis. CD was mimicked by other gastric granulomatous diseases (actinomyces, 1 case; chronic granulomatous disease of childhood, 1 case). Gastric biopsy can be used to identify or support the diagnosis of CD in children in the appropriate clinicopathologic setting. 相似文献
994.
Angelica Putnam Suzanne Yandow Cheryl M. Coffin 《Pediatric and developmental pathology》2003,6(2):173-178
Adamantinoma, a rare bone lesion of the tibia and fibula, has two distinct variants, classic adamantinoma and osteofibrous
dysplasia-like adamantinoma. Composite lesions have not been described. Aneurysmal bone cyst is a benign cystic lesion which
may also occur in the tibia and fibula. We report an unusual case of classic adamantinoma with osteofibrous dysplasia-like
areas and foci of secondary aneurysmal bone cyst with prominent giant cells. A lesion was diagnosed in a 17-year-old girl
with a 14-year history of a slowly enlarging left tibial mass and increasing deformity. Pathologically, the predominant pattern
was classic adamantinoma, with minor foci of osteofibrous dysplasia-like adamantinoma and areas of secondary aneurysmal bone
cyst with abundant multinucleated giant cells. We report the clinical, radiologic, and pathologic features of this case, and
summarize lesions associated with secondary aneurysmal bone cyst. To our knowledge, the association of adamantinoma with secondary
aneurysmal bone cyst has not been previously reported. 相似文献
995.
Unusual Hepatic Tumor with Features of Mesenchymal Hamartoma and Congenital Solitary Nonparasitic Cyst 总被引:2,自引:0,他引:2
We report a hepatic tumor in an adolescent that does not fit into any of the described categories of liver tumors. The patient presented with hepatomegaly, abdominal pain, and normal liver function test; the tumor was cystic in imaging studies. The resected specimen, result of a partial hepatectomy, measured 21 cm and was multicystic with solid areas. Microscopically, the cysts were lined by a mucous-producing or intestinal-type epithelium, associated with smooth muscle and small mucous-producing glands. The solid component contained fibrous and adipose tissue, smooth muscle and thick-walled vessels. Aneuploidy was demonstrated by flow cytometry. We interpreted the tumor as having features of a mesenchymal hamartoma and congenital solitary nonparasitic cyst. It is conceivable that the lesions originated with small peribiliary glands with dilatation and intestinal metaplasia. 相似文献
996.
Chao-Jung Lin Wan-Fu Su Chih-Hung Wang 《European archives of oto-rhino-laryngology》2003,260(5):277-279
Foreign bodies in a mobile tongue are rarely presented to the laryngologist, because such bodies are commonly lodged superficially and are easily removed by the patients themselves or by general practitioners. Thus, it is rare that a foreign body totally embedded in the mobile part of the tongue presents as an enlarged tongue mass. We have described a 64-year-old female with a 3-month history of an enlarged mass in the anterior right tongue. Physical examination showed a mass located in the anterior right tongue, with intact mucosa and normal color. A benign tongue neoplasm was considered first. However, a fish bone totally embedded in the mobile tongue with granuloma formation was encountered during the incisional biopsy operation. Complete removal of the foreign body with granuloma was achieved under local anesthesia. There was no neuromuscular or neurosensory deficit of the tongue in the follow-up period of 2 years. Although an embedded foreign body in the mobile tongue is a rare condition, it should be considered in the work-up of a patient with an enlarged tongue mass, with or without a history of swallowing a foreign body. 相似文献
997.
The effect on the middle-ear cavity of an absorbable gelatine sponge alone and with corticosteroids 总被引:2,自引:0,他引:2
Osman Bahadir Sevim Aydin Refik Caylan 《European archives of oto-rhino-laryngology》2003,260(1):19-23
The objectives of this study were to establish whether there is an obvious difference between intact mucosa and abraded mucosa of the middle-ear cavity in respect to the potential side effects from the application of absorbable gelatine sponge (Gelfoam) and to investigate if Gelfoam combined with corticosteroid ointment (cortimycine, sterile 1% hydrocortisone acetate) can reduce the occurrence of these effects. Twenty Albino rats were used in the study. These animals were divided into four groups, with ten ears in each group. In group A, the middle-ear mucosa was kept intact, and Gelfoam was inserted into the middle-ear cavity. In group B, the middle-ear mucosa was abraded, and Gelfoam was inserted. In group C, Gelfoam with corticosteroid was implanted over the intact mucosa, and in group D, the mucosa was abraded prior to the insertion of Gelfoam with corticosteroid. The changes were evaluated 8 weeks postoperatively. In group A, there was a minimal increase in fibroblastic activity, vascular proliferation with mild to moderate fibrosis and all but two tympanic membranes were perfectly normal. However, in group B, we encountered a significant increase in fibroblastic activity, vascular proliferation and fibrosis, and we observed that all tympanic membranes were moderately to severely thickened. These histopathologic changes related to Gelfoam were noted to be decreased in group C and especially in group D. As previously reported in the literature, Gelfoam was found to promote the formation of connective tissue in the middle-ear cavity regardless of the status of the mucosa. The unwanted effects of this material may be decreased if it is combined with corticosteroids in the middle-ear cavity. 相似文献
998.
Results of uvulopalatopharyngoplasty after diagnostic workup with polysomnography and sleep endoscopy: a report of 136 snoring patients 总被引:1,自引:0,他引:1
We subjectively and objectively evaluated 136 patients with socially unacceptable snoring (SUS) or obstructive sleep apnoea syndrome (OSAS) treated with uvulopalatopharyngoplasty (UPPP) after a diagnostic workup by sleep registration (polysomnography, PSG) and sleep endoscopy. Of the 136 patients, there were 88 with OSAS and 48 with SUS. The results of the procedure were considered subjectively to be an improvement in 38 (79%) of the SUS patients and in 74 (84%) of the patients with OSAS. In 36 (40%) of the 88 patients with OSAS, repeating PSG postoperatively was considered unnecessary because of obvious improvement. Of the 52 patients with a measurement after UPPP, a decrease in the apnoea hypopnoea index (AHI) was found in 38 (73%; median decrease: 48%), and AHI dropped below 20 in 32 (62%). The apnoea index (AI) was available in 49 (56%) patients and was reduced in 31 (63%; median decrease: 73%). An overall positive result in the 88 patients with OSAS (combining available data on subjective and objective results) was therefore found in 61 (69%; positive subjective result and AHI <15) or 71 (81%; positive subjective result and decrease in AHI), respectively, depending on the definition. We conclude that after diagnostic workup by sleep registration and sleep endoscopy, the success rate of UPPP increases as compared to historical controls. 相似文献
999.
Dana M. Hartl Stéphane Hans Jacqueline Vaissière Daniel F. Brasnu 《European archives of oto-rhino-laryngology》2003,260(4):175-182
This study was designed to determine which objective acoustic or aerodynamic parameters allowed a homogeneous group of patients with unilateral vocal fold paralysis (UVFP) to be distinguished from an age-matched and smoking-matched control group and to search for linear correlations between the objective parameters and the subjective breathiness ratings. Eight patients with recent-onset UVFP and 12 controls were prospectively studied. The acoustic parameters measured for the vowel /a/ at a comfortable frequency and intensity were: jitter, shimmer, harmonics-to-noise ratio, cepstral peak prominence, the difference between the levels of the first two harmonics and the relative energy above 6 kHz. Aerodynamic parameters included the mean flow rate during a sustained /a/ and intraoral pressure during the production of the phoneme /pi/. The long-term average spectrum was calculated for 40 s of text, and the relative average energies in four frequency bands were compared. Six judges rated a mid-/a/ sample using a five-parameter scale with four levels of severity. Nonparametric statistical analysis revealed significant differences ( P<.05) between the UVFP group and the control group for 14 of the 19 parameters studied. Correlations between the objective parameters and perceived breathiness differed in the two groups. Correlations were not always as expected as based on previous literature reports. These measurements provided an objective qualification of voice in patients with UVFP and successfully distinguished them from the normal controls. The objective acoustic and aerodynamic measurements had generally low linear correlations with breathiness ratings in the control group. Higher correlations were seen in the UVFP group, in which breathiness was best correlated with airflow measurements. 相似文献
1000.