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排序方式: 共有6422条查询结果,搜索用时 15 毫秒
41.
MD Cohen ST Auringer JL Grosfeld CA Galliani NA Heerema 《Canadian Metallurgical Quarterly》1993,23(6):463-466
The purpose of this study is to present three patients with multifocal primary neuroblastoma, to review the literature, and describe the radiographic findings. SUBJECTS AND METHODS: Three children with multifocal neuroblastoma have been identified. The case histories and imaging findings in these patients are reviewed. RESULTS: Two children had synchronous and one child had metachronous multifocal primary neuroblastoma. The primary tumors were both in the abdomen in one patient, both in the chest in another patient, and in the chest and abdomen in the third patient. Evidence for multifocal origin of these tumors, rather than metastatic spread, is presented. CONCLUSION: Multifocal primary neuroblastomas can occur. The tumors maybe synchronous or metachronous. Awareness of this disorder may prevent errors in diagnosis and staging. Although not identified in our patients there is a strong familial incidence of neuroblastomas in those patients with multifocal tumors. 相似文献
42.
C Tribouilloy V Ruiz R Roudaut JC Eicher B Denis JR Lusson JL Rey JL Schmit JP Lesbre 《Canadian Metallurgical Quarterly》1996,25(28):1276-1280
OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria. 相似文献
43.
Lipopeptide L-733,560 is a water-soluble derivative of pneumocandin B0 that exhibits enhanced anti-Candida activity. We investigated the in vitro activity of L-733,560 compared with those of amphotericin B, flucytosine, and itraconazole, against fluconazole-resistant (n = 44) and fluconazole-susceptible (n = 46) Candida albicans isolates. Tests were performed with a photometer-read broth microdilution method with RPMI-2% glucose and National Committee for Clinical Laboratory Standards reference strains. Except for those of itraconazole, MICs were not significantly different between the two groups of isolates, as expected for agents with different mechanisms of action. L-733,560 was the most active agent against C.albicans, with MICs for 50 and 90% of the strains tested of 0.01 and 0.06 microgram/ml, respectively. 相似文献
44.
RM Bionta G Blewitt CB Bratton D Casper A Ciocio R Claus M Crouch ST Dye S Errede GW Foster W Gajewski KS Ganezer M Goldhaber TJ Haines TW Jones D Kielczewska WR Kropp JG Learned JM LoSecco J Matthews HS Park LR Price F Reines J Schulz S Seidel E Shumard D Sinclair HW Sobel JL Stone L Sulak R Svoboda G Thornton van der Velde JC C Wuest 《Canadian Metallurgical Quarterly》1987,36(1):30-36
45.
JD Haag LA Shepel BD Kolman DM Monson ME Benton KT Watts JL Waller CC Lopez-Guajardo DJ Samuelson MN Gould 《Canadian Metallurgical Quarterly》2003,63(18):5808-5812
It has previously been shown that the Copenhagen (COP) rat contains several genetic loci that contribute to its mammary tumor-resistant phenotype after 7,12-dimethylbenz(a)anthracene (DMBA) administration. One of these loci, mammary carcinoma susceptibility 1 (Mcs1), is located on the centromeric end of chromosome 2 and appears to act in a semidominant fashion. To confirm the existence and independent action of this locus and also aid in the identification of the physical location of the Mcs1 gene, congenic lines were generated by transferring the Mcs1 COP allele onto a Wistar Furth (WF) genetic background. Male carriers were genotyped using microsatellite markers spanning 20-30 cM of the Mcs1 locus. One of the congenic lines minimally retained the COP allele at D2Mit29 on the centromeric end of chromosome 2 and extended distally to D2Rat201. Heterozygous Mcs1 carrier rats were interbred, and the female offspring were treated with DMBA. The female rats from the Mcs1 congenic line that carried one or two COP alleles of the Mcs1 region had a significantly reduced (65 and 85%, respectively) tumor development (P < 0.001) compared with rats carrying zero COP alleles at this locus. A WF.COP-D2Mit29/D2Rat201 homozygous congenic strain derived at the N10 generation was treated with DMBA, and the COP homozygous rats developed 1.5 +/- 0.3 carcinomas/rat versus 6.3 +/- 0.5 in WF control rats (P < 0.0001). Fine mapping of this congenic interval using several recombinant lines identified three genetic loci within the Mcs1 congenic region that independently supported a tumor resistance phenotype. These genetic loci have been termed Mcs1a, Mcs1b, and Mcs1c. In rats for which each locus was homozygous for the COP allele, tumor development was reduced by approximately 60% compared with littermate controls. The identification of these independent loci within the Mcs1 COP allele provide a model of the genetic complexity of cancer. 相似文献
46.
47.
JL Stringer 《Canadian Metallurgical Quarterly》1995,68(2):407-413
In a particular brain region specific changes in inhibition or excitation may be the basis of seizure initiation. Alternatively, changes in the balance of excitation and inhibition in the circuit, which may be detectable as polysynaptic responses may be more important indicators of epileptogenesis. That the appearance of polysynaptic responses precedes the initiation and, therefore, may be necessary for the onset of epileptiform activity in the hippocampal-parahippocampal circuit was tested using the chemical convulsant pentylenetetrazol. Excitation and paired-pulse inhibition were measured in CA1 and the dentate gyrus of the urethane-anaesthetized rat before and after administration of pentylenetetrazol. In addition, three polysynaptic responses were monitored. In both CA1 and the dentate gyrus, pentylenetetrazol, 100 mg/kg, caused a trend towards increased excitability and caused a relatively mild loss of inhibition. Two polysynaptic responses appeared in the dentate gyrus after the administration of pentylenetratrazol, both apparently mediated through the entorhinal cortex. A polysynaptic response of the CA1 pyramidal neurons to contralateral angular bundle stimulation was not observed. These experiments demonstrate that pentylenetetrazol will facilitate only the appearance of polysynaptic responses mediated through the entorhinal cortex. These results support the hypothesis that pentylenetetrazol has a specific action within the entorhinal cortex that may facilitate the synchronization and spread of epileptiform activity. These results are also consistent with the hypothesis that the appearance of polysynaptic responses may be necessary for the onset of epileptogenesis in the hippocampal-parahippocampal circuit. 相似文献
48.
49.
FM Scott AM Treston GL Shaw I Avis J Sorenson K Kelly EC Dempsey AB Cantor M Tockman JL Mulshine 《Canadian Metallurgical Quarterly》1996,14(2-3):239-251
Monitoring respiratory epithelial biology may reveal individuals with incipient lung cancer. The expression of neuroendocrine (NE) markers in pulmonary epithelium is thought to be central to lung development, repair of injury and may contribute to carcinogenesis. In this study, we evaluate several candidate NE markers to determine the feasibility of prospective analysis of clinical specimens. The potential NE markers include the enzyme L-DOPA decarboxylase (DDC), the neuropeptide gastrin releasing peptide (GRP), and peptidyl-glycine alpha-amidating monooxygenase (PAM), the bifunctional enzyme responsible for the final bioactivation step of many neuropeptides. A comparison of PAM activity and DDC levels in 30 lung cancer cell lines indicated that peptide amidating activity may be an indicator of NE status. Bronchoalveolar lavage (BAL) fluid from subjects at risk of developing second primary lung cancer and from volunteers was obtained. The activity of the first PAM enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), ranged from not detectable to 507 pmol/h/mg protein in 57 specimens. The second PAM enzyme, peptidylamidoglycolate lyase (PAL), ranged from not detectable to 414 pmol/h/mg protein in 56 specimens. Using cluster analysis by the average linkage method, a group of enzyme values with PHM greater than 230 pmol/h/mg protein was determined. Long-term follow-up of these patients for new second primary lung cancers may help to determine the potential predictive value of PAM detected in the BAL fluid. 相似文献
50.
E Darai F Filippini JL Benifla JN Guglielmina G Pennehouat B Deval P Madelenat 《Canadian Metallurgical Quarterly》1996,25(4):353-359
OBJECTIVE: Our objective was to determine the interest of laparoscopic assisted vaginal hysterectomy. STUDY DESIGN: Between January 1991 to december 1994, 80 patients had laparoscopically assisted vaginal hysterectomy. We reviewed with particular emphasis characteristic indications, complications. RESULTS: Eighty were performed as laparoscopically assisted vaginal hysterectomy. 14 patients (17.5%) had laparotomy conversion; because of size of uterus in 3 cases, suspected ovarian tumor in 3 cases. Pelvic adherences in 4 cases, urinary tract injuries in 1 case, hypercapnia in 1 case, hemorrhage in 2 cases. 9 patients experienced febrile morbidity and 1 urinary infection. 1 patient received 2 units of packed red blood cells. The hospital stay was 5 days for laparoscopically assisted vaginal hysterectomy versus 5.9 for laparotomic hysterectomy. CONCLUSION: Laparoscopically assisted vaginal hysterectomy offers a technique to convert certain abdominal hysterectomies into vaginal hysterectomies with a 17.5% laparoconversion rate. 相似文献