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991.
The Authors report the results based on 20 years of practice on obstetric psycho-prophylaxis (PPO). Data on presence at course, on frequency, on primipares/pluripares ratio, on labour, on timing and mode of delivery, are assembled. Moreover, neonatal status at birth and at 10th day of life, are investigated. The data obtained were compared with a control group, constituted by women without any treatment before delivery. The acquired experience confirm the utility of PPO in the ordinary clinical practice.  相似文献   
992.
It has been shown that a marked increase in the levels of Rlα sub-units and a decrease in RIIβ sub-unit levels correlate with neoplastic transformation or with the mitogenic response of normal cells to hormones and growth factors. The selective down-regulation of RIα and the following induction of RIIβ determine cell-growth arrest and differentiation of several cancer cells. To directly address the question whether the 2 protein-kinase-A(PKA) isoforms play different roles in the control of proliferation and cell-cycle distribution, we introduced and over-expressed the different PKA sub-units in Chinese-hamster-ovary (CHO) cells via retroviral-vector-mediated gene transfer. Whereas CHO cells treated with RIα anti-sense oligodeoxynucleotides were growth arrested and accumulated in the G0/G1 phases of the cell cycle, infection of CHO cells with a retroviral vector in order to over-express RIα determined growth advantages in monolayer conditions and substantially increased their cloning efficiency in soft agar. These events correlated with a sustained percentage of cells in S phase induced by RIα over-expression in the infected cells. In contrast, CHO cells infected with retroviral vectors over-expressing either a RIIβ sub-unit or a Cα catalytic sub-unit of PKA exhibited growth arrest within a few days of culture and accumulated in the G2-M phase of the cell cycle. The results of our study demonstrate that the different PKA sub-units play different and specific roles in the control of cell growth and cell-cycle distribution.  相似文献   
993.
Antigen 90K is produced by several tumor-cell lines and by patients with cancer. Its function has not yet been clarified, although recent reports suggest that it plays a role in the tumor—host relationship—for example by stimulation of natural killer and lymphokine-activated killer-cell activity. Previous studies have indicated that 90K expression may be under the influence of interferon-α. Here, we provide evidence that both interferon-α and -γ can enhance the secretion of 90K and augment the level of specific mRNA expression in 3 ovarian carcinoma cell lines (OVCAR-3, HTB-77 and SKOV-6). However, interferon-γ leads to depletion of cellular 90K whereas interferon-α increases both secreted and cellular 90K levels. In equimolar concentrations, Interferon-α was always superior to interferon-γ in augmenting 90K protein or mRNA levels. Combinations of TNF with interferon-γ were highly synergistic both in reducing cell proliferation and in increasing 90K secretion and mRNA expression. This synergism was seen to a lesser extent with interferon-α.  相似文献   
994.
Eight families with two or more first-degree relatives affected with ovarian carcinoma were identified among a series of 138 consecutive ovarian cancer patients. History of breast cancer was reported in six of the eight families. Five of 19 patients with familial cancer developed ovarian cancer as a second primary tumor following breast carcinoma, whereas only 6/130 sporadic cases had a previous history of breast cancer. No significant difference was detected in clinical and pathological features between sporadic and familial cases. However, in three high-risk families ovarian cancer tended to develop at a younger age compared with other familial cases and with sporadic occurrences, and nulliparity was less frequent in the familial group. These observations emphasize the need to take into account multiple factors-in addition to positive family history-for the evaluation of genetic predisposition to ovarian carcinoma.  相似文献   
995.
This study was undertaken to better comprehend the reasons for the scarcity of Hodgkin and Reed-Sternberg (H-RS) cells in Hodgkin's disease (HD) despite their expression of “proliferation-associated antigens”. To this end, we assessed the relative frequency of mitotic phases and nuclear damage (detected by in situ end-labeling of DNA strand breaks) in CD30+ large cells of nodular sclerosis and mixed cellularity HD. Our results show that a) most CD30+ cells in HD exhibit abortive mitoses, with a highly significant arrest at the metaphase-ana/telophase transition, and b) many of these elements, i.e. mainly H-RS cells, show fragmentation of nuclear DNA, suggesting imminent or actual death. Percentages of CD30+ cells that entered mitosis and those with DNA strand breaks were of a similar order of magnitude and correlated significantly in a linear fashion. These findings are consistent with the concept that cell deletion is the major cause of the paucity of H-RS cells in HD.  相似文献   
996.
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998.
OBJECTIVES: The aim of this study was to clarify the clinical relevance of ventricular tachyarrhythmias assessed by 24-h ambulatory electrocardiograms (ECG) in a large, unique, and prospectively evaluated athletic population. BACKGROUND: For athletes with ventricular tachyarrhythmias, the risk of sudden cardiac death associated with participation in competitive sports is unresolved. METHODS; We assessed 355 competitive athletes with ventricular arrhythmias (VAs) on a 24-h ambulatory (Holter) ECG that was obtained because of either palpitations, the presence of > or = 3 premature ventricular depolarizations (PVDs) on resting 12-lead ECG, or both. RESULTS: Athletes were segregated into three groups: Group A with > or = 2,000 PVDs/24 h (n = 71); Group B with > or = 100 <2,000 PVDs/24 h (n = 153); and Group C with only <100 PVDs/24 h (n = 131). Cardiac abnormalities were detected in 26 of the 355 study subjects (7%) and were significantly more common in Group A (21/71, 30%) than in Group B (5/153, 3%) or Group C athletes (0/131, 0% p < 0.001). Only the 71 athletes in Group A were excluded from competition. During follow-up (mean, 8 years), 70 of 71 athletes in Group A and each of the 284 athletes in Groups B and C have survived without cardiovascular events. The remaining Group A athlete died suddenly of arrhythmogenic right ventricular cardiomyopathy while participating in a field hockey game against medical advice.Frequent and complex ventricular tachyarrhythmias are common in trained athletes and are usually unassociated with underlying cardiovascular abnormalities. Such VAs (when unassociated with cardiovascular abnormalities) do not convey adverse clinical significance, appear to be an expression of "athlete's heart syndrome," and probably do not per se justify a disqualification from competitive sports.  相似文献   
999.
PURPOSE: The use of electrophysiologic studies (EPS) for the localization of accessory atrioventricular connections in Wolff-Parkinson-White syndrome (WPW) requires accurate evaluation of the site of bypass tract insertion. Doppler myocardial imaging (DMI) is a new ultrasound technique that allows the detection of abnormal and early regional myocardial depolarization. The purpose of this study was to identify an abnormal pathway site in WPW patients. METHODS: Twenty-one patients with ventricular preexcitation were studied by DMI. Two-dimensional color DMI, velocity maps, acceleration maps, and pulsed-wave applications were used. A subsequent diagnostic EPS was performed. The results of EPS were taken as the gold standard diagnostic procedure. Radiofrequency catheter ablation therapy was then performed on all patients. RESULTS: The anomalous pathway was detected by DMI in 16 (76%) of 21 patients (9 [90%] of 10 with left pathways and 7 [64%] of 11 with right pathways), with respect to results of the EPS. Pathway detection was better with pulsed-wave DMI (76%) with its higher temporal resolution as compared with M-mode velocity map (57%) and acceleration map (47%). In most of the patients with successful radiofrequency ablation, an immediate resolution of the abnormal ventricular depolarization occurred and was detectable by DMI. CONCLUSIONS: Our findings demonstrate the feasibility of DMI to assess the early ventricular contraction associated with atrioventricular accessory pathways. Therefore, DMI appears to be a clinically useful adjunct to noninvasive evaluation of abnormal myocardial depolarization in WPW and to evaluate the results after radiofrequency ablation, even though its accuracy is considerably better for left-sided accessory pathways than for right-sided ones.  相似文献   
1000.
Atrophic chronic gastritis and Helicobacter pylori infection are considered possible causes of iron deficiency anemia, and sideropenic anemia is also frequent after subtotal gastrectomy. In this study, thirty-three patients who underwent subtotal gastrectomy for primary adenocarcinoma of stomach were follow-up for at least 3 years, and included in this analysis. The presence of atrophic gastritis and H. pylori infection were detected by biopsy sampling and endoscopy every year after surgery. The iron status was evaluated by the assay of serum ferritin, serum iron and hemoglobin level. Statistical analysis revealed that atrophic gastritis was associated with lower iron serum levels, and gastric stump H. pylori infection was related to lower serum ferritin levels; on the contrary, no correlation of these factors with sex, age, malabsorption symptoms and stage of tumor was found. Atrophic chronic gastritis and Helicobacter pylori infection seem to play an important role as possible causes of post gastrectomy anaemia.  相似文献   
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