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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Fabio Piscaglia Valeria Camaggi Matteo Ravaioli Gian Luca Grazi Matteo Zanello Simona Leoni Giorgio Ballardini Giulia Cavrini Antonio Daniele Pinna Luigi Bolondi 《Liver transplantation》2007,13(6):857-866
The best prioritization of patients with hepatocellular carcinoma (HCC) waiting for liver transplantation under the model for end-stage liver disease (MELD) allocation system is still being debated. We analyzed the impact of a MELD adjustment for HCC, which consisted of the addition of an extra score (based on the HCC stage and waiting time) to the native MELD score. The outcome was analyzed for 301 patients with chronic liver disease listed for liver transplantation between March 1, 2001 and February 28, 2003 [United Network for Organ Sharing (UNOS)-Child-Turcotte-Pugh (CTP) era, 163 patients, 28.8% with HCC] and between March 1, 2003 and February 28, 2004 (HCC-MELD era, 138 patients, 29.7% with HCC). In the HCC-MELD era, the cumulative dropout risk at 6 months was 17.6% for patients with HCC versus 22.3% for those patients without HCC (P = NS), similar to that in the UNOS-CTP era. The cumulative probability of transplantation at 6 months was 70.3% versus 39.0% (P = 0.005), being higher than that in the UNOS-CTP era for patients with HCC (P = 0.02). At the end of the HCC-MELD era, 12 patients with HCC (29.3%) versus 57 without HCC (58.8%) were still on the list (P = 0.001). Both native and adjusted MELD scores were higher (P < 0.05) and progressed more in patients with HCC who dropped out than in those who underwent transplantation or remained on the list (the initial-final native MELD scores were 17.3-23.1, 15.5-15.6, and 12.8-14.1, respectively). The patients without HCC remaining on the list showed stable MELD scores (initial-final: 15.1-15.4). In conclusion, the present data support the strategy of including the native MELD scores in the allocation system for HCC. This model allows the timely transplantation of patients with HCC without severely affecting the outcome of patients without HCC. 相似文献
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94.
Emergency surgical procedure for failed methotrexate treatment of cervical pregnancy: a case report.
Andrea Tinelli Antonio Malvasi Daniele Vergara Sergio Casciaro 《The European journal of contraception & reproductive health care》2007,12(4):391-395
Cervical pregnancy (CP) is a rare and dangerous condition, which may cause a massive haemorrhage. Ultrasonographic diagnosis consists of the visualization of the gestational sac and trophoblastic invasion in an endocervical localization. CP treatment modalities include dilatation and curettage (D&C) usually followed by intracervical tamponade, cervicotomy, angiographic embolization, ligation of the uterine arteries, and chemotherapy with methotrexate (MTX). MTX administration is a very appealing therapeutic modality of CP in the first trimester because of its convenience and efficacy. We report a case of unsuccessful treatment of a CP with systemic MTX administration, which led to an emergency surgical procedure for a sudden massive vaginal haemorrhage. A vaginal ligation of the cervical branches of the uterine arteries was carried out, followed by suction curettage, D&C and insertion of an intrauterine sterile tampon that was removed after 48 hours. The patient did not require a blood transfusion. Histological examination of the specimen confirmed the CP. 相似文献
95.
Onelio Geatti Brahm Shapiro Pier Giuseppe Orsolon Gianni Proto Ugo Paolo Guerra Francesco Antonucci Daniele Gasparini 《European journal of nuclear medicine and molecular imaging》1994,21(1):17-22
Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial). 相似文献
96.
Deletion of the Major Proteolytic Site of the Helicobacter pylori Cytotoxin Does Not Influence Toxin Activity but Favors Assembly of the Toxin into Hexameric Structures 总被引:1,自引:0,他引:1
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Daniela Burroni Pietro Lupetti Cristina Pagliaccia Jean Marc Reyrat Romano Dallai Rino Rappuoli John L. Telford 《Infection and immunity》1998,66(11):5547-5550
The Helicobacter pylori cytotoxin is proteolytically cleaved at a flexible hydrophilic loop into two subunits. Deletion of the loop sequences had no effect on biological activity of the toxin in the HeLa cell vacuolation assay but favored the organization of the protein into hexameric rather than heptameric structures. 相似文献
97.
Antonella d’Arminio Monforte Paola Cinque Luca Vago Aleandro Rocca Antonella Castagna Cristina Gervasoni Maria Rosa Terreni Roberto Novati Andrea Gori Adriano Lazzarin Mauro Moroni 《Journal of neurology》1996,244(1):35-39
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination
to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents.
CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr
virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR
was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one
autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven
and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive)
were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma
therapy affected the sensitivity of both histological and CSF-PCR methods.
Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996 相似文献
98.
Josep Oriola Cristina Hernandez Rafael Simo Anna Barceló Roser Casamitjana Enric Vilardell & Francisca Rivera-Fillat 《Clinical endocrinology》1996,44(2):207-212
OBJECTIVE Genetic analysis is now essential for the accurate screening of families with multiple endocrine neoplasia type 2 (MEN2). We present the genetic analyses by both haplotype and direct RET proto-oncogene mutation analysis in seven Mediterranean MEN 2A families and have compared these results with biochemical screening tests and pathological examinations.
DESIGN Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A. 相似文献
DESIGN Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A. 相似文献
99.
100.
Giuseppe Micieli Marco Magri Giorgio Sandrini Cristina Tassorelli Giuseppe Nappi 《Cephalalgia : an international journal of headache》1988,8(3):193-201
In this study the variations in pupil diameter induced by different stimuli (dark-light adaptation, light reflex, electric stimulation of the sural nerve) were investigated in episodic (in the active or remission phases) and in chronic cluster headache (CH) patients. Pupil size monitoring was performed with a monocular, infrared TV pupillometer, and sural nerve stimuli were applied after the pain threshold had been measured as the flexion reflex threshold of the biceps femoris muscle (RIII reflex). The results were compared with those obtained in patients with "peripheral" (third neuron) Horner's syndrome and in healthy sex- and age-matched controls. On the symptomatic side we found an impairment of pupil response to light flashes and nociceptive stimuli; similar findings were sometimes evident on the pain-free side, too. These results substantiate previous observations that in cluster headache a dysfunction of the integrative central nervous system pathways also exists intercritically and mostly bilaterally, involving both autonomic regulation and pain perception mechanisms. 相似文献