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991.
Correale P Caraglia M Pepe S Ricciardi B Barile C Montagnani S Pacelli R Bianco A Tagliaferri P 《International journal of oncology》1994,4(2):423-427
Human colon carcinoma LoVo/DX cells, which have been selected from parental LoVo for resistance to doxorubicin, express a typical multidrug resistant (MDR-1) phenotype. We have investigated whether phorbol 12-myristate 13-acetate (PMA) which often induces phenotypical changes in human tumor cells could, at the same time, modulate differentiation and sensitivity of LoVo/DX cells to doxorubicin. After 48 h exposure to 100 nM PMA, morphological changes became evident on LoVo/DX cells which showed elongated cytoplasm and dendritic-like structures: moreover immunocytochemical findings were suggestive of neuroendocrine-like differentiation. Under the same experimental conditions, LoVo/DX became sensitive to doxorubicin and showed enhanced intracellular drug-accumulation and reduced membrane expression of the 170 kD glycoprotein GP-170, which is the cellular product of the mdr1 gene. We conclude that pharmacological induction of tumor cell differentiation by PMA is paralleled by abrogation of drug resistance in a colon carcinoma MDR-1 cell line. 相似文献
992.
993.
Sex selection may be inadvertently performed in in-vitro fertilization--embryo transfer programmes 总被引:3,自引:2,他引:1
Tarin Juan J.; Bernabeu Rafael; Baviera Amparo; Bonada Maria; Cano Antonio 《Human reproduction (Oxford, England)》1995,10(11):2992-2998
The present study aims to ascertain whether sex selection maybe inadvertently performed in human in-vitro fertilization (IVF)and embryo transfer (IVF-embryo transfer) programmes when selectingfor high quality embryos (those with the fastest cleaving ratesand/or the best morphology) at the fresh transfer cycle. Allpatients entering into the study were treated with gonadotrophinsafter pituitary suppression with gonadotrophin-releasing hormoneagonists (GnRHa) and had intrauterine embryo transfer on day2 post-insemination. These patients were retrospectively dividedinto three groups according to whether the difference in meannumber of cells between embryos transferred and all embryosavailable for transfer in a given cycle was less than (negativeselection), equal to (no selection) or greater (positive selection)than zero. In cycles resulting in singleton births, the sexratio of the resulting babies was significantly (P 0.005) shiftedtoward the female (88.8%) and to the male (90.0%) in the negativeand positive selection groups respectively. No shift in sexratio was observed in cycles resulting in multiple births. Maternalage was another independent factor affecting sex ratio at birth.Sex ratio was significantly (P 0.05) skewed in favour of males(62.7%) and females (71.4%) in women <35 and 235 years ofage respectively. Maternal age, number of embryos transferredand the event of selecting or not selecting the slowest cleavingembryos for transfer were entered automatically in a three-groupdiscriminant model for distinguishing cycles resulting in onlyboys, both boys and girls, and only girls. These data suggestthat (i) sex selection may be inadvertently performed in IVF-embryotransfer programmes when selecting for high quality embryosat the fresh transfer cycles; (ii) human endometria may be favourable,indifferent or hostile to either fast cleaving or slow cleavingembryos depending on maternal age; and (iii) naturalsex selection may be performed for social, psychological ormedical reasons. 相似文献
994.
Athanasios Zahariou Maria Karamouti George Karagiannis Polyanthi Papaioannou 《Journal of neurology》1995,242(Z2):S61-S62
Poster Session 1
Child neurology 相似文献995.
Background: In the past 4 years we performed operations on 90 patients who suffered from morbid obesity. Five different operative
techniques were available, vertical banded gastroplasty (VBG), silastic ring vertical gastroplasty (SRVG), gastric banding
operation, adjustable silicone gastric banding (ASGB) and biliopancreatic diversion (BPD). Methods: Two of these operations
were mainly utilized. The ASGB was done routinely. The SRVG was used particularly for patients with hiatal hernia. Only one
patient, who had a deformed pylorus, underwent the BPD. Results: Eleven patients had to be reoperated due to complications
after the first operation of gastric restriction. They were divided into three groups depending on the type of complication:
reoperation due to lack of compliance, due to technical failure, or due to other complications. In the last group we observed
three patients with band perforation into the stomach without epigastric pain. This complication has, to our knowledge, only
been described in very few cases. Conclusion: In some patients it remained difficult to reach adequate compliance, although
we kept close contact with them after the operation. We do not yet know the reasons for the band perforation observed in three
patients. 相似文献
996.
Dr. Maurizio Vaglini MD Dr. Filiberto Belli MD Mario Santinami MD Flavio Arienti MD Giorgio Parmiani MD Laura Persiani MD Nicola Santoro MD Maria Grazia Inglese MD Fortunato D'Elia MD Natale Cascinelli MD 《Annals of surgical oncology》1995,2(1):61-70
Background: Therapies of advanced melanoma patients with interleukin-2 (IL-2) and cytotoxic lymphocytes have produced interesting results, but a larger diffusion of these treatments is limited by the severe side effects due to IL-2 systemic infusion. A strictly regional administration of IL-2 and cells by an isolation perfusion (IP) in extracorporeal circulation (ECC) for the treatment of regional melanoma metastases could improve tolerability and efficacy of this specific modality of immunotherapy.
Methods: Ten patients were submitted to adoptive immunotherapy with IL-2 and lymphokine-activated killer (LAK) cells by IP in ECC. The schedule of treatment included the first course of a 5-day systemic administration of IL-2 (Proleukin, EuroCetus 9–12 × 106 IU/M2/day continuous infusion); autologous LAK cells were obtained via leukapheresis and after in vitro activation were given (range 8–28 × 109) along with IL-2 (120-2,400 IU/ml of perfusion priming) to the affected limb by IP; IL-2 (9–12×106 IU/m2/day) was also administered by systemic continuous infusion for 5 days starting on the day after IP.
Results: All patients concluded the treatment without any major local or systemic toxicities. Clinical responses included one complete and six partial remissions; three patients had stable disease. All patients are alive. Follow-up after IP ranged from 12 to 35 months (median: 22). The analysis of circulating lymphocytes revealed the rapid disappearance of LAK cells, suggesting their extravasation and/or endothelial adhesion in perfused tissues.
Conclusions: IP with IL-2 and LAK cells is a new approach for the treatment of in-transit metastases due to cutaneous melanoma. The treatment appears to be feasible and reliable. Further biological and immunological studies should permit amelioration of the present modality of treatment. 相似文献
997.
Friedman D Cuneo S Valenzano M Marinari GM Adami GF Gianetta E Traverso E Scopinaro N 《Obesity surgery》1995,5(3):308-313
Background: 239 pregnancies occurred in 1136 women who had undergone biliopancreatic diversion (BPD). Methods: There were
73 abortions, and 14 pregnancies are presently in their course. The 152 term pregnancies (six twins) occurred in 129 women
2-173 months (mean 42.7) after BPD. Mean age and current excess weight were 31.4 years (20-42) and 29.1% (-6.9-78.2), and
mean excess weight loss was 72.9% (30.4-110.5). Results: Mean weight gain during pregnancy was 6.2 kg (-21-25). In 32 patients
(21%), parenteral nutritional support was needed. In all the other patients (79%), the usual supplementations were given.
Of the newborns, 122 were delivered at term (84.7%) with a mean weight of 2842.4 g (1760-4600 g) and a mean length of 48.5
cm (43-59 cm), while the 22 preterm babies (15.3%) weighed 2151.1 g (1400-3850 g) and had a length of 44.6 cm (33-56 cm).
Forty infants (27.8%) were small for gestational age but 17 of them weighed more than 2500 g. Eleven twins (one abortion at
26th week) were also delivered, with a mean weight of 2088.6 g (1200-3100 g) and a mean length of 45.6 cm (35-50 cm). Delivery
was spontaneous in 85 instances (56%), while vacuum extractor was used in one, and 66 cesarean sections were performed. There
were two birth malformations, one infant died after surgery for meconium obstruction and two died from unknown causes. Of
the 129 women, 35 had been infertile before BPD. Conclusions: Disappearance of infertility and decrease of pregnancy risk
are to be considered among the beneficial effects of weight reduction following BPD. 相似文献
998.
Peter J. Theuvenet Zbigniew Dunajski Maria J. Peters Jan M. van Ree 《Brain topography》1999,11(4):305-313
Somatosensory evoked magnetic fields and electrical potentials were measured in eight patients with unilateral neuropathic pain. After median nerve stimulation on the painful side, the amplitudes of the evoked responses were enhanced 2 to 3 times at a latency of about 100 ms compared to the responses of the contralateral, unaffected side. After posterior tibial nerve stimulation an enhancement was found at latencies around 110 ms and 150 ms. The scalp distribution of the magnetic field at the latencies of abnormal responses was dipolar and the responses could be ascribed to a current dipole. Three (of the eight) patients underwent spinal cord stimulation (SCS) for their pain. The enhancement of the evoked responses to stimulation of the painful side decreased after spinal cord stimulation. After a long period of spinal cord stimulation only (e.g., a year) during which the patient reported to be pain free, these abnormal responses were no longer observed. 相似文献
999.
Polito C La Manna A Mansi L Rambaldi PF Papale MR Marte A Di Toro R 《Pediatric nephrology (Berlin, Germany)》1999,13(9):876-879
Body growth was studied in 32 subjects with vesicoureteric reflux (VUR), diagnosed following the prenatal finding of urinary
tract dilatation, who had normal renal filtration function and who received antibacterial prophylaxis by the first few days
of life. They were followed for 1–5 years (mean 2.3 years). Most had persistent VUR during the 1st year of life. Body growth
performance was compared with that of 94 subjects with VUR diagnosed and treated by us after the neonatal period. During the
follow-up period, none of the patients with prenatally detected VUR had a height Z score below –2, nor a weight-for-height
index below 90%, and 1 had variations in height Z score ≥1. The difference in the percentage of patients with prenatally detected
VUR (1/32) and those with VUR diagnosed and treated after the neonatal period (20/94) who had variations in height Z score
≥1 was significant (P=0.035). Patients with prenatally detected VUR and normal renal filtration function, given antibacterial prophylaxis by the
first few days of life, have normal body growth, although VUR still persists.
Received: 19 March 1998 / Revised: 10 February 1999 / Accepted: 10 February 1999 相似文献
1000.
Dixit MP Cabansag MR Piscitelli J Greifer I Silverstein DM 《Pediatric nephrology (Berlin, Germany)》1999,13(2):139-142
Amyloidosis is a complication of long-term hemodialysis treatment. The major histological feature of hemodialysis-associated
amyloidosis (HAA) is the deposition of amyloid fibrils in the affected lesions, due, in part, to elevated serum β2-microglobulin (β2M) levels. In vitro studies reveal that serum immunoglobulin light and heavy chains co-deposit with β2M
in tissues affected by HAA. Only one study of HAA has been performed in young dialysis patients. We therefore assessed risk
factors for HAA in a group (n=30) of young (18.7±0.9 years) patients receiving chronic, uninterrupted hemodialysis using cellulose acetate membranes. All
patients initiated dialysis before reaching 18 years of age. The pre-dialysis serum β2M level was 49.7±3.9 mg/l (normal 0–2.4
mg/l). Since serum albumin was normal (4.3±0.1 mg/dl) and serum protein/albumin was elevated (1.7±0.0, normal 1.2–1.5), indicating
increased circulating protein, we assayed immunoglobulins in the same patients. The serum immunoglobulin levels (expressed
as a percentage of the total level of serum proteins) were elevated (21.3±0.9%, normal 11.1%–21.0%). The Kt/v was 1.37±0.03,
suggesting that the high levels of serum β2M and immunoglobulins were not due to inadequate dialysis in these patients. Patients
with residual renal function (Kr) did display significantly lower serum levels of β2M (33.2±2.3, P=0.03). Furthermore, improved clearance of β2M correlated with higher values of Kr (r=0.914). In contrast, serum levels of immunoglobulin (22.6±3.7, P=0.5) were unaffected by Kr. In addition, there was no correlation between older age at onset of dialysis and serum levels
of either β2M (r=0.107) or immunoglobulins (r=0.321). Finally, the length of time on dialysis had no effect on serum levels of either β2M (r=0.105) or immunoglobulins (r=0.092). Taken together, these results indicate that young hemodialysis patients may be at risk for HAA.
Received: 13 January 1998 / Revised: 1 June 1998 / Accepted: 2 June 1998 相似文献