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81.
Use of spiral and non-spiral computed tomography arterial portography in the detection of potentially malignant liver masses 总被引:2,自引:0,他引:2
NOEL YOUNG TOM SING KAI PING WONG MICHAEL HOLLANDS NOEL TAIT 《Journal of gastroenterology and hepatology》1997,12(5):385-391
The present study assesses the usefulness of computed tomography (CT) arterial portography (CTAP) in detecting and defining the number and anatomy of potentially malignant liver lesions. One hundred and one adults studied in 1993 and 1994 were retrospectively reviewed, including patients with primary or secondary tumours for possible resection and patients with non-hepatic malignancies in whom the detection of liver metastases would preclude surgery. Twenty-three patients underwent non-spiral CT studies and 78 had studies on a spiral unit, with 22 of these having single phase and 56 having dual phase studies to overcome artefact problems. The relationship between lesion size and detection sensitivity is critical. On non-spiral studies, the overall lesion detection sensitivity and positive predictive value was 69 and 90%, respectively. Detection sensitivity was 100 and 20% for lesions > 1 cm and < 1 cm, respectively. On single phase spiral CTAP the overall detection sensitivity and positive predictive value was 80 and 66%, respectively. Detection sensitivity for lesions > 1 cm and < 1 cm was 100 and 0%, respectively. On dual phase spiral CTAP the overall detection sensitivity and positive predictive value was 76 and 71%, respectively. For lesions > 1 cm and < 1 cm the sensitivity was 81 and 55%, respectively. Eighteen patients with non-hepatic malignancies with unsuspected metastatic spread did not proceed to major surgery because of liver metastases detected on CTAP. Perfusion artefacts occurred in 30 and 64% of non-spiral and of initial portal venous spiral CTAP studies, respectively. By using the double-phase technique, these artefacts were substantially diminished. In conclusion, CTAP is a valuable tool for assessing the presence, site and size of possible liver tumours and confers a benefit even when previous ultrasound and conventional CT have already been used. In addition, CTAP has a lower limit of useful resolution of approximately 1 cm. Perfusion artefacts can be reduced by a dual phase protocol. 相似文献
82.
Anthony BOERS Qiang LI Melinda WONG Marian MILLER Geoff LITTLEJOHN 《International journal of rheumatic diseases》2006,9(1):43-48
Aim: We performed a semiprospective and retrospective review of all admissions to a single institution of systemic lupus erythematosus (SLE) patients, admitted due to active disease. The aim was to describe differences in disease activity as a cause of hospital admissions between patients originating from South‐East Asia/China (SAC) and Caucasians. Method: There were 210 patients admitted for active disease, with a total of 567 admissions for active SLE over a 16‐year period. Allowing for patients who had left our database, there was a total of 3415 patient years of observation. Results: Patients from SAC with a flare requiring admission presented earlier in their disease course and with more active disease than did Caucasians (median SLE Disease Activity Index 13 vs. 8, P= 0.002). They had longer inpatient stays (7 vs. 5 days P = 0.03). There was a trend to higher rates of re‐presentation to hospital for flare (59% in SAC patients vs. 41% in Caucasians, P = 0.09) with more subsequent admissions (3 vs. 2 P = 0.06) despite a shorter period of observation. Conclusions: South‐East Asian/Chinese were more likely to be diagnosed with class III/IV glomerulonephritis and require cyclophosphamide both at presentation and subsequent admissions. More patients from SAC were readmitted to hospital for severe central nervous system disease after their first hospital admission. In this population, lupus patients had more severe flares and more frequently required admission for these than Caucasians. 相似文献
83.
The number of patients who suffer from vertigo or dizziness becomes greater during the sixth and seventh decades of life and is now increasing to total, which could be related to recent longer life expectancy. Pertinent medical care should be given to those patients to better obtain so-called quality of life (QOL), and this could be attained with the help of accurate diagnosis. In general,accurate diagnosis is made by thorough neurotological examinations. 相似文献
84.
GERALD J KOHN HENRY J SCHWARTZ BORIS H RUEBNER ANNA J WONG MICHAEL J LAWSON 《Journal of gastroenterology and hepatology》1997,12(3):198-203
Both suppressor oncogene and proliferative activity are believed to indicate colon cancer risk. The retinoblastoma (Rb) gene is a suppressor oncogene affecting cell differentiation. Retinoblastoma gene inactivation is associated with tumour development. However, the relation of the Rb protein to cell proliferation and colon tumour formation is unknown. Retinoblastoma protein quantity was correlated with proliferative activity in flat, unaffected mucosa specimens from 36 cancer patients, 21 non-cancer control subjects and in 29 tumour tissue samples from cancer patients. Nuclear Rb protein was measured by using automated CAS-200 image analysis of monoclonal antibody labelled frozen sections from fresh, surgically removed tissue. All colon cells within 15 whole crypts were imaged. Proliferative activity was also measured by using image analysis with Ki-67 monoclonal antibody. Retinoblastoma protein content correlated directly with proliferative activity in flat mucosa of non-cancer control subjects ( r = 0.63; P < 0.001; n = 21). A significant correlation was also found in flat mucosa specimens of non-metastatic (Duke's stages A and B) cancer patients ( r =0.52; P < 0.01; n = 22). However, Rb protein did not correlate with proliferation in flat mucosa from metastatic (Duke's stages C and D) cancer patients ( r =0.03; NS; n =14) or in cancer tissue ( r =0.068; NS; n =29). Mucosal Rb protein in the colon normally increases as proliferation increases. Dissociation between Rb protein and colon proliferation may occur in flat mucosa in patients with a higher risk of metastatic tumour growth. Future studies comparing Rb protein quantity and proliferative activity may help identify high-risk colon cancer patients. 相似文献
85.
C. J. KENYON R. V. NARDI D. WONG G. HOOPER I. R. WILDING & D. R. FRIEND 《Alimentary pharmacology & therapeutics》1997,11(1):205-213
Background: Colonic delivery of corticosteroids may reduce the side-effects commonly associated with their use. Therefore, we tested the ability of the naturally occurring polysaccharide guar gum to deliver a corticosteroid, dexamethasone, to the colon using pharmacoscintigraphy. Guar gum is metabolized in the colon by resident bacterial enzymes to trigger drug release. Materials: Each subject (eight per group, parallel study design) was administered one of four dexamethasone (9 mg) tablet formulations, radiolabelled with 153Sm using neutron activation, under fasted conditions. One formulation was designed to release drug rapidly following ingestion while the other three formulations were designed to delay release of dexamethasone to varying degrees. Progression of the formulations down the gastrointestinal tract was followed by gamma scintigraphy. Serum concentrations were measured over time to relate disintegration profiles of the tablets with pharmacokinetic observations. Results: The immediate release formulation disintegrated in the stomach, on average, within 20 min of dosing. One of the three delayed release preparations (CD1) began to disintegrate in the small intestine 1.7±1.0 h after dosing. The second and third delayed release preparations (CD2 and CD3) did not begin to disintegrate until 5.8±2.3 and 3.6±1.6 h after dosing, respectively. All three colonic delivery preparations completely disintegrated in the colon ranging from 7.8±2.7 h (CD1) to 12.4±3.2 h (CD2) following oral administration. Pharmacoscintigraphic data indicated that 72–82% of the dexamethasone was delivered into the colon although not all the dexamethasone delivered into the colon was absorbed. Conclusions: Simple guar gum formulations are capable of delivering the corticosteroid dexamethasone to the colon of normal subjects. Locally delivered corticosteroids may be useful in the treatment of ulcerative colitis and Crohn's disease. Pharmacoscintigraphic evaluation is a useful method to discriminate between the in vivo behaviour of colonic delivery systems. 相似文献
86.
CHI WAI CHENG SIU FOON PETER CHAN LUNG WAI CHAN CHI KWOK CHAN CHI FAI NG HO YUEN CHEUNG SHU YIN EDDIE CHAN WAI SANG WONG FERNAND MAC-MOUNE LAI KA FAI TO MIU LING LI 《International journal of urology》2005,12(5):449-455
AIM: To compare bacillus Calmette-Guerin (BCG) with epirubicin in adjuvant therapy of superficial bladder transitional cell carcinoma, with respect to recurrence, progression and survival. Prognostic factors are also evaluated. METHODS: Between October 1991 and September 1999, all patients harboring superficial bladder cancers (Ta or T1) with any of the relevant criteria (stage>a, grade>1, size>1 cm, multiple or recurrent tumors), after complete transurethral resection were randomized to receive either 81 mg Connaught strain BCG or 50 mg epirubicin. Patients with recurrences were eligible to crossover, even repeatedly, until progression. Recurrence, progression and survival were analyzed in relation to initial treatment, patient characteristics and tumor characteristics. RESULTS: There were 209 patients included in the study, 149 men and 60 women. The mean age was 69.9 years (range, 24-92). The BCG group consisted of 102 patients and the epirubicin group contained 107 patients. Final analysis was made at a median follow up of 23, 47 and 61 months for recurrence, progression and survival, respectively. The 10-year Kaplan-Meier estimates for recurrence-free, progression-free and disease-specific survival were 61%, 78% and 80%, respectively, for the BCG group. The corresponding figures were 32%, 74% and 92%, respectively, for the epirubicin group. Time to recurrence differed significantly between two treatment groups (P=0.0004). Multiplicity increased the risk of recurrence, while grading influenced recurrence, progression and disease specific survival. CONCLUSIONS: Bacillus Calmette-Guerin prolonged time to recurrence when compared with epirubicin. Grading was shown to be a universal prognostic factor for recurrence, progression and disease specific survival. 相似文献
87.
Dyschromatosis universalis with X-linked ocular albinism 总被引:4,自引:0,他引:4
A 10-year-old Chinese boy with the characteristic skin manifestations of dyschromatosis universalis is described. In addition, the patient had congenital nystagmus with poor visual acuity, and ophthalmological examination revealed foveal hypoplasia and albino-like fundi. Histopathology showed giant pigment granules in the skin. Based upon the finding of giant pigment granules in clinically normal skin of the patient's mother, the patient was diagnosed as a case of dyschromatosis universalis with X-linked ocular albinism. To the best of our knowledge, this is the first documented case of this combination. 相似文献
88.
After-hours radiological procedures are essential but expensive in any major teaching hospital. Using the criteria that radiological procedures performed after-hours should have a reasonable probability of influencing or changing patient management acutely, a study of the justification of after-hours radiological procedures was performed at the Princess Alexandra Hospital. Computer print-outs were used to select the patients based on the dates and times of the procedures. Their charts were then reviewed. The study found that most after-hours radiological procedures were justified. However, it also identified certain procedures that need not be performed or at least could be reduced after-hours. The procedures were: (i) computed tomography (CT) head – epilepsy, meningitis; (ii) CT abdomen – trauma (intubated) – unable to examine abdomen; (iii) CT spine – obvious unstable fractures; (iv) Ultrasound abdomen – biliary colic (afebrile); and (v) Ultrasound kidneys – renal failure (afebrile). 相似文献
89.
90.
Prague women's drinking before and after the 'velvet revolution' of 1989: a longitudinal study 总被引:1,自引:0,他引:1
Results are presented of a follow-up study in which a representative sample of 608 Prague women aged 20–49 years in 1987 at first interview was re-interviewed in 1992 3 years after the revolution that ended the 41 years of the Communist era in Czechoslovakia. The average yearly consumption of alcohol in the followed-up female sample increased between 1987–92 from a reported 3.6 litres to 4.8 litres. The percentage of heavier drinkers (with average daily consumption of over 20 g alcohol) increased from 7.2% to 14.0%. The women expressed increased tolerance of drunkenness in their attitudes to drinking. The consumption increase was mainly due to increased drinking frequency of spirits and to increased quantity of beer consumed per occasion. The consumption increase was largest in women working as free-lance and the newly emerging self-employed women; economically inactive women did not increase their consumption. Women who reported a positive impact of the socio-political changes on their personal lives and an expansion of social contacts also reported larger than average consumption increases. A coincidence of stressful, possibly self-inflicted, life events and increased alcohol use was observed and interpreted as probably a two-way influence. 相似文献