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991.
A number of genes have altered activity in small-cell lung cancer (SCLC), but especially genes of the myc family (c-myc, L-myc and N-myc) are expressed at high levels in SCLC. Most studies have explored expression at the mRNA level, whereas studies of myc family oncoprotein expression are sparse. We examined the expression of myc proto-oncogenes at the mRNA and protein level in 23 cell lines or xenografts. In the cell lines, the doubling time and the cell-cycle distribution, as determined by flow-cytometric DNA analysis, were examined to establish whether the level of myc-gene-family expression correlated with proliferative parameters. All tumours expressed at least one myc family member at the mRNA level. Exclusive c-myc mRNA expression was demonstrated in 8 tumours, L-myc in 7 and N-myc in I. Five tumours expressed both c-myc and L-myc, and 2 tumours expressed both c-myc and N-myc. In general, the level of expression of c-myc and N-myc was similar at the mRNA and the protein level. Expression of c-myc was positively correlated with the proliferative index (sum of S and G2 + M phases) of cell lines, but not with the population doubling time. In general, L-myc-expressing cell lines had a low proliferative index. There was no systematic difference in myc expression between cell lines and xenografts of individual tumours.  相似文献   
992.
Objective To compare obstetric and perinatal outcome between two different expectant managements in women with prelabour rupture of the membranes (PROM).
Design A randomised study.
Participants One thousand three hundred and eighty-five women with rupture of the membranes at 34 to 42 weeks without contractions.
Interventions Women without contractions 2 h after admission were randomised to early induction the following morning after PROM (early induction group) or induction two days later (late induction group). Women with contractions starting within 2 h after admission were included in the calculations as a short latency group. Digital examinations of the cervix were avoided until onset of active labour. Labour was induced with oxytocin in both groups if no spontaneous contractions occurred or if chorioamnionitis or fetal distress was detected.
Main outcome measures The frequency of spontaneous deliveries, operative deliveries, maternal and neonatal infections.
Results In nulliparous women, a higher rate of spontaneous deliveries was found in the late induction group (89%) compared with the early induction group (81%) (   P < 0.05  ). The ventouse extraction rate was 7% and 14% respectively (   P < 0.05  ). A low (2–4%) caesarean section rate was recorded and did not differ between the groups. Endometritis was detected in six women after delivery. Sixty-one children were treated with antibiotics, and no difference could be detected between the groups.
Conclusions A higher rate of spontaneous deliveries was found among nulliparous women with prolonged latency as compared with brief latency prior to induction. A protocol of no digital examination before labour was associated with infrequent maternal and fetal morbidity, regardless of latency.  相似文献   
993.
Flow cytometric DNA analysis with assessment of S-phase fraction and DNA ploidy was compared to Nottingham histologic grade. The study population consisted of 654 patients who presented between 1987 and 1996 with primary operable breast cancer and whose tumours had been analysed for S-phase fraction and DNA ploidy at the time of surgery. Grade, tumour size, node status, steroid receptor status, age, S-phase fraction and DNA ploidy were analysed univariately and multi-variately in a Cox proportional hazard analysis. In the univariate analyses all parameters were statistically significantly associated with breast cancer mortality during the follow-up period of 2–11 years. The most powerful predictor of death from breast cancer in the multiple regression analysis was grade. Patients with grade 1 tumours have excellent prognosis. We conclude that tumour grade is a strong prognostic indicator applicable to all breast cancer patients, regardless of size and nodal status, and advocate its general use.  相似文献   
994.
The European Journal of Health Economics -  相似文献   
995.
996.
The blood flow in an experimental adenocarcinoma in the rat liver was determined with the 133Xe-washout technique before and after hepatic artery ligation (HAL). There was an initial reduction of the washout of 50%. This was further reduced after 1 day by 50%, which was maintained for 7 days. Seven days after HAL or sham procedures the 133Xe-washout was of similar magnitude in the liver tumours, although after the sham procedure the tumours were larger (3.4 g vs. 1.5 g). The estimated tumour blood flow was then approximately 0.04 ml x min-1 x g-1. The influence on normal liver parenchyma of HAL was a reduction at 30 minutes, which was maintained for 7 days. Postacton--a synthetic vasopressin--did not influence the 133Xe-washout in normal liver parenchyma in non-tumour, as well as in tumour-bearing animals. There was no influence of Postacton on the 133Xe-washout in the liver tumours. Thirty minutes after HAL Postacton gave a reduction of blood flow in normal liver parenchyma of tumour-bearing animals, which is thus only from the portal vein. In tumours Postacton did not significantly reduce the tumour blood flow immediately after HAL.  相似文献   
997.
Appraisal of caregiving and its relationship to family burden and experienced mental health problems in the relatives were investigated as part of a multi-centre study of the quality of mental health services in Sweden performed in 1997. The sample was drawn from relatives of involuntarily and voluntarily admitted patients to acute psychiatric wards. The instrument used was a semi-structured questionnaire, interviewing relatives about the burden, experience of mental health problems and appraisal of the caregiving situation. The results showed a high proportion of relatives engaged in caregiving activities on a daily basis the month before the patient's admission to hospital and a high proportion of relatives appraising the caregiving activities negatively. The burden was more extensive if the relative and the patient were living together, had a longer duration of their relationship, if the relative was rendering caregiving on a daily basis and if the relative appraised caregiving negatively. The relatives' psychological distress was not related to their negative appraisal of caregiving, nor was patient characteristics, such as diagnosis and level of psychosocial functioning. The only factor found to influence the relatives' psychological distress was the duration of relationship to the patient. Interventions reducing psychological distress for relatives who have known the patients for more than 20 years, who live with the patient, who give care on a daily basis and who appraise their caregiving negatively are suggested.  相似文献   
998.
Root surface texture after different scaling modalities   总被引:1,自引:0,他引:1  
Root surface texture after scaling with hand instruments, ultrasonic scalers (Amdent 830 and Cavi-Med 2000), and a sonic sealer (Titan-S) was assessed in vitro. The experimental material consisted of 48 extracted human teeth divided into six groups. Root surface texture was assessed with scanning electron microscopy (SEM). Hand and sonic instrumentation produced large grooves and removed cementum evident at a magnification of ×70. while the root surface alterations after ultrasonic instrumentation were not detectable below a magnification of ×500. The working principle of each scaling instrument in relation to its effect on the root surface was discussed.  相似文献   
999.
Correlation among sibling marker genotypes may invalidate the results of family‐based tests of association in the presence of linkage. We apply an empirical variance estimation method, which is implemented in the program package FBAT, on Caucasian families with asthma in the presence and absence of linkage and compare the results with those obtained using the TDT (TDTEX‐PAIRS) on the same data sets. Our results indicate that both tests generally perform comparably in either setting. © 2001 Wiley‐Liss, Inc.  相似文献   
1000.
The newly discovered peptide nociceptin/orphanin FQ has been found to increase reactivity to pain and to influence locomotor activity after intracerebroventricular administration. This study investigated the possible role of hippocampal nociceptin/orphanin FQ in spatial learning and in spontaneous locomotion. Male rats were trained in the Morris water task after microinjection of 10 nmol nociceptin/orphanin FQ or artificial cerebrospinal fluid (as control) into the CA3 region of the dorsal hippocampus. Nociceptin/orphanin FQ was found to severely impair spatial learning without interfering with swimming performance. Itrahippocampal injection of nociceptin/orphanin FQ markedly decreased exploratory locomotor activity including vertical movements (rearing). The data suggest that nociceptin/orphanin FQ is a potent modulator of synaptic plasticity within the hippocampus.  相似文献   
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