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41.
Alphafetoprotein (AFP), an oncofetal antigen, plays very important roles in the early embryonic life and oncogenesis. Under various physiological and pathological conditions AFP exhibits microheterogeneity, probably as a result of differential expression of its epitopes. To analyse the epitopes we have developed a panel of monoclonal antibodies against human AFP purified by a new and efficient method using an immunoadsorbent consisting of polyclonal antibodies immobilized on cyanogen bromide activated Sepharose. Clones producing antibodies of various isotypes, e.g. IgG1, IgG2a, IgG2b, IgA and IgM have been subcloned and characterized. The antibodies showed high avidity for AFP (with half-maximal binding concentrations between 0.012 and 3.87 nM). Mutual inhibition efficiencies of a panel of 14 monoclonal antibodies were determined by RIA. Based on these inhibition data a computer program was used to group these antibodies with respect to their "epitope specificity distance". As a result of this grouping, clones have been identified which can recognize at least five different epitopes on AFP. This panel of antibodies may be very useful for analysis of the epitopic variation of AFP under various physiological and pathological conditions. 相似文献
42.
Lissoni P Mandalà M Rovelli F Casu M Rocco F Tancini G Scardino E 《European urology》2000,37(5):569-572
OBJECTIVE: In addition to sex steroids, prolactin (PRL) may also stimulate prostate cancer growth. Abnormally high blood levels of PRL have been noted in metastatic prostate cancer patients. However, most studies have been limited to the evaluation of basal levels of PRL rather than to investigate its secretion in response to classical endocrine dynamic tests. This study was carried out to analyze PRL secretion in metastatic prostate cancer patients both at basal conditions and in response to L-Dopa and metoclopramide, which represents the most classical inhibitory and stimulatory tests for PRL secretion, respectively. METHODS: The study included 12 patients with metastatic prostate cancer. On separate occasions, PRL secretion was evaluated in response to L-Dopa (500 mg orally) and to metoclopramide (10 mg i.v. as a bolus). Serum levels of PRL were measured by RIA. RESULTS: Mean PRL concentrations significantly increased after metoclopramide administration, even though no PRL response occurred in 6 of 12 patients. L-Dopa was unable to reduce PRL levels, which, in contrast, paradoxically significantly increased in response to L-Dopa, with mean values comparable to those achieved after metoclopramide injection. CONCLUSION: By showing a paradoxical stimulatory effect of L-Dopa on PRL secretion and a lack of response to metoclopramide in some patients, this study would suggest the existence of evident alterations in the neuroendocrine regulation of PRL release in advanced prostate cancer. 相似文献
43.
M Mandalà G Curigliano P Bucciarelli G Ferretti P M Mannucci M Colleoni A Ventura G Peruzzotti G Severi P G Pelicci R Biffi F Orsi S Cinieri A Goldhirsch 《Annals of oncology》2004,15(4):590-593
BACKGROUND: To analyze the influence of the prothrombotic gene mutation factor V G1691A (factor V Leiden) and prothrombin G20210A on the risk of a first episode of catheter-related deep venous thrombosis (DVT) in a group of patients with breast cancer treated with chemotherapy. PATIENTS AND METHODS: Between January 1999 and February 2001, the occurrence of a first symptomatic DVT was investigated in a cohort of 300 consecutive patients with locally advanced or metastatic breast cancer treated at a single institution with fluorouracil-based chemotherapy, administered continuously through a totally implanted access port. A nested case-control study included 25 women (cases) with catheter-related DVT and 50 controls without DVT matched with cases for age, identical chemotherapy, stage of disease and prognostic features. The G1691A factor V and G20210A prothrombin mutation genotypes were analyzed. RESULTS: Five cases [20%; 95% confidence interval (CI) 9% to 39%)] and two controls (4%; 95% CI 1% to 14%) were heterozygous carriers of G1691A factor V (P = 0.04). The age-adjusted odds ratio for catheter-related DVT was 6.1 (95% CI 1.1-34.3). Only one patient (case) had the G20210A prothrombin gene mutation. Time from start of chemotherapy infusion to DVT was not significantly different between patients with (median 31 days) and without (median 43 days) G1691A factor V mutation (P = 0.6). CONCLUSIONS: Factor V Leiden carriers with locally advanced or metastatic breast cancer have an increased risk of developing catheter-related DVT during chemotherapy. 相似文献
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46.
We report a case of a 40-year-old man who had presented with a spontaneous suprapubic urinary leak from a well-healed suprapubic cystostomy tract scar, 20 years following a successful scrotal tube substitution urethroplasty done for a post-traumatic urethral stricture. Preoperative contrast studies suggested a recurrent bulbomembranous urethral stricture. Excision biopsy of the suprapubic fistulous tract revealed scar cancer infiltrating the bladder wall. Of 3 similar cases reported in the past, only 1 had bladder involvement. Ours is the second such case with bladder involvement. 相似文献
47.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
48.
Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis 相似文献
49.
Role of clinical, radiological, and neurophysiological changes in predicting the outcome of tuberculous meningitis: a multivariable analysis 下载免费PDF全文
Misra UK Kalita J Roy AK Mandal SK Srivastava M 《Journal of neurology, neurosurgery, and psychiatry》2000,68(3):300-303
OBJECTIVES: The role of EEG and evoked potentials has not been evaluated in predicting the prognosis of tuberculous (TB) meningitis. The present study was aimed at evaluating the prognostic significance of clinical, radiological, and neurophysiological variables using multi-variable analysis. METHODS: Patients with TB meningitis diagnosed on the basis of clinical, radiological, and CSF criteria have been prospectively evaluated. All the patients were subjected to a detailed neurological evaluation. The outcome was defined 6 months after starting treatment on the basis of the Barthel index (BI) score into poor (BI <12) and good recovery (BI> or =12). Death was included in the poor recovery group for statistical analysis. Thirteen clinical (age, sex, seizure, focal weakness, stage of meningitis, Glasgow coma scale score, methyl prednisolone therapy), CT (infarction, hydrocephalus, tuberculoma) and neurophysiological (EEG, motor and somatosensory evoked potentials) variables were evaluated employing single variable logistic regression followed by multivariable logistic regression analysis. The best set of predictors were obtained by stepdown logistic regression analysis. RESULTS: Fifty four patients were included in the present study. Their age ranged between 5 and 62 years, 11 were children younger than 12 years and 14 were female. Nine patients were in stage I meningitis, 12 in stage II, and 33 in stage III. On single variable logistic regression analysis the significant predictors of 6 months outcome of TB meningitis included focal weakness, Glasgow coma scale (GCS), motor evoked potential (MEP) and somatosensory evoked potential (SEP). On multivariable analysis the best set of predictors comprised focal weakness, GCS, and SEP. CONCLUSIONS: In patients with TB meningitis focal weakness, GCS, and SEP are the best predictors of 6 month outcome. 相似文献
50.