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991.
OBJECTIVE: Is there any correlation between follicular fluid (FF) steroid levels and the occurrence of cytogenetic abnormalities in unfertilized human oocytes? DESIGN: Cytogenetic analysis was carried out on 397 oocytes, and the steroid content of 104 corresponding FF was analyzed using high-pressure liquid chromatography. Ovarian stimulation was performed by clomiphene citrate and human menopausal gonadotropin (hMG) or by hMG combined with a gonadotropin-releasing hormone agonist (GnRH-a) pretreatment. RESULTS: Oocyte maturity was correlated with an increasing FF progestin content and a significant decrease of androstenedione (A) levels. Chromosomal analysis revealed 84 of all oocytes to be abnormal (polyploid or aneuploid and/or prematurely condensed chromosomes present). In this group, A levels and A to estradiol ratios were significantly higher. Although progestin levels were higher in GnRH-a/hMG cycles, the incidence of oocyte normality was not different between the two stimulation schemes. More abnormal oocytes were found in patients with good sperm morphology. CONCLUSIONS: Oocyte abnormality correlates with higher A levels in the corresponding FF. Oocyte fertilization is also determined by intrinsic oocytic factors other than maturity. 相似文献
992.
BACKGROUND: Intraarterial chemotherapy of oral and oropharyngeal cancer with cisplatin (cis-diamminedichloroplatinum [II]) has experienced a revival in the last decade. Side-effects of the therapy were very low with concomitant systemic infusion of the neutralizing agent sodium thiosulphate. The requisite dose of the chemotherapeutic agent which safely leads to apoptosis of oral cancer cells has not yet been assessed in vitro, nor has the combination of cisplatin and sodium thiosulphate been examined for the potential reduction of cytotoxicity in oral cancer cells. STUDY DESIGN: In a panel of two tongue squamous cancer cell lines and an oesophageal cancer cell line as control and comparison, cisplatin (0.2-10 microgram/ml) was combined with sodium thiosulphate (0-0.5 mg/ml). RESULTS: 10 microgram/ml of cisplatin proved to be 100% antiproliferative, while any additional concentration of sodium thiosulphate decreased this effect. At the maximum dose of cisplatin, a sodium thiosulphate/cisplatin concentration relation of less than 6:1 still effected cytotoxic activity of >80%. An increase of cisplatin concentration led to higher cytotoxicity irrespective of sodium thiosulphate concentration. The oesophageal cell line was more sensitive to cisplatin and to sodium thiosulphate than the tongue cell lines. CONCLUSIONS: In this study, it was found that high concentrations of cisplatin are necessary in oral cancer to reach cytotoxic levels which support high-dose intraarterial chemotherapy by which these levels might be reached. A sodium thiosulphate/cisplatin concentration ratio within the tumour of less than 6:1 may be allowed without compromising the cytotoxic activity of cisplatin. 相似文献
993.
Laparoscopic antireflux surgery. What is real progress? 总被引:4,自引:0,他引:4
OBJECTIVE: The authors aim to substantiate, with objective arguments, potential advantages of laparoscopic versus open antireflux surgery in the light of the recent crude experience of the Louvain Medical School Hospital. METHODS: Seventy-two consecutive patients with disabling gastroesophageal reflux disease ([GERD], n = 56), symptomatic hiatal hernia without GERD (n = 5), or unsatisfactory outcome after unsuccessful antireflux procedure (n = 11) were operated on by laparotomy (n = 28), laparoscopy (n = 39), or thoracotomy (n = 5). The antireflux procedure was a subdiaphragmatic Nissen fundoplication (n = 60), an intrathoracic Nissen fundoplication (short esophagus, n = 3), a subdiaphragmatic 240 degrees fundoplication (severe motility disorders, n = 3), a Lortat-Jacob repair (hiatal hernia without GERD, n = 5), and a duodenal diversion (delayed gastric emptying, n = 1). RESULTS: Major postoperative morbidity included two pulmonary embolisms (one laparoscopy patient and one laparotomy patient), and one hemothorax (one thoracotomy patient). Mean hospital stay was 6.4 days for laparoscopy, 7.8 days for laparotomy, and 12.5 days for thoracotomy. Postoperative morphine consumption (patient-controlled analgesia) averaged 47 mg/48 hrs (laparoscopy) versus 46 mg/48 hrs (laparotomy with primary antireflux surgery) (p > 0.05). Although 93% of the laparoscopy patients returned to work within 3 weeks after surgery, 92% of the laparotomy and thoracotomy patients resumed their activity after more than 6 weeks. At follow-up, 87.5% of the patients were asymptomatic or had inconsequential symptoms, 9.8% had disabling side effects, and 2.7% had persistent or recurring esophageal symptoms. There were four parietal herniations, i.e., one incisional hernia and one recurrence of a repaired umbilical hernia in the laparotomy group, and two herniations of the wrap into the chest--probably related to a premature return to manual work--in the laparoscopy group. Three laparoscopy patients were dissatisfied with the esthetics of their scars. Lower esophageal sphincter pressure and esophageal acid exposure in the laparoscopy patients who were investigated were normal in 100% and 95%, respectively. CONCLUSIONS: Laparoscopy is a good approach for achieving successful antireflux surgery in selected cases. However, its fails to substantially reduce postoperative complication rate and discomfort, duration of the hospital stay, and the risk of esthetic sequela. Early return to work is questionable for manual workers. The subdiaphragmatic Nissen fundoplication is not an all-purpose antireflux procedure. 相似文献
994.
G De Sanctis F Ascoli M Brunori 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(24):11507-11511
The acid unfolding pathway of apominimyoglobin (apo-mini-Mb), a 108-aa fragment (aa 32-139) of horse heart apomyoglobin has been studied by means of circular dichroism, in comparison with the native apoprotein. Similar to sperm whale apomyoglobin [Hughson, F. M., Wright, P. E. & Baldwin, R. L. (1990) Science 249, 1544-1548], a partly folded intermediate (alpha-helical content approximately 35%) is populated at pH 4.2 for horse heart apomyoglobin. For this intermediate, Hughson et al. proposed a structural model with a compact subdomain involving tertiary interactions between the folded A, G, and H helices, with the remainder of the protein essentially unfolded. As described in this paper, a folding intermediate with an alpha-helical content of approximately 33% is populated at pH 4.3-5.0 also in apo-mini-Mb. The acid unfolding pathway is similarly affected in both the native and the mini apoprotein by 15% trifluoroethanol, a helix-stabilizing compound. Thus, the folding of the apo-mini-Mb intermediate is similar to that observed for the native apoprotein, in spite of the absence in the miniprotein of the A helix and of a large part of the H helix, which are crucial for the stability of apo-Mb intermediate. Our results suggest that acquisition of a folded state in apo-mini-Mb occurs through an alternative pathway, which may or may not be shared also by apo-Mb. 相似文献
995.
The right gastroepiploic artery (GEA) was used as a pedicled conduit for direct coronary artery revascularization in 20 patients presenting with more or less exhausted saphenous vein resources. The early angiographic patency of the GEA conduit appears to be satisfactory when it is connected to the right coronary artery system. A distinct disadvantage of GEA grafting is the necessity to enter the abdominal cavity, which may lead to probably rare and as yet unrecognized morbidity. Future abdominal surgery may injure the GEA conduit unless its topographic relations to the prepyloric antrum, liver and diaphragm are properly recognized. The surgeon must then be prepared to encounter antegastric, retrogastric, antehepatic, transhepatic and retrohepatic routes of the redirected intraabdominal artery. The present paper addresses this problem. Preoperative angiography of the celiac trunk and superior mesenteric artery may be helpful in decision-making when a patient reports or records show that a graft has been harvested from the abdominal cavity. 相似文献
996.
I. C. Bennett A. Khan R. De Freitas M. A. Chaudary R. R. Millis 《ANZ journal of surgery》1992,62(8):628-633
Thirty cases of phyllodes tumour (cystosarcoma phyllodes) of the breast that presented to the Clinical Oncology Unit at Guy's Hospital were reviewed. Tumours were classified as benign, malignant or borderline according to the following histological criteria: mitotic rate, nuclear pleomorphism, stromal overgrowth and tumour margins. In 14 (46.5%) cases the tumours were considered histologically benign, in 11 (36.5%) malignant, and in five (17%) borderline. Recurrence was seen in a similar proportion of patients with tumours classified as benign (21 %) and malignant (18 %) according to histological criteria. Malignant lesions tended to recur earlier. Infiltrating tumour margins were noted in all patients and stromal overgrowth in all hut one in whom recurrence was observed. Risk of recurrence also appeared to he related to tumour size. Only one patient developed distant metastases and died of her disease. Because of treatment variation no conclusion can he made regarding optimal therapy but the importance of adequate clearance, either through wide excision or mastectomy, is emphasized for all phyllodes tumours irrespective of histological features. 相似文献
997.
F Armellini M Zamboni L Rigo I A Bergamo-Andreis R Robbi M De Marchi O Bosello 《International journal of obesity (2005)》1991,15(12):847-852
The aim of this study was to check the reliability of sonography in measuring small variations in quantities of subcutaneous and intra-abdominal fat. Twenty-six obese women (BMI 39 +/- 6) underwent a 15 day very low calorie diet. The study included, both before and after very low calorie diet, computed tomography measurements of total (AT), visceral (VAT) and subcutaneous (SAT) adipose tissue areas, visceral/subcutaneous area ratio (V/S), waist/hip circumference ratio measurements (W/H), and ultrasound measurements of abdominal subcutaneous skin-muscle thickness, intra-abdominal muscle-aorta thickness and intra-abdominal/subcutaneous thickness ratio. Weight reduction was from 101 +/- 17 to 95 +/- 16 kg (P less than 0.001). W/H dropped from 0.83 +/- 0.06 to 0.82 +/- 0.07 (n.s.). VAT dropped from 158 +/- 72 to 134 +/- 61 cm2 (P less than 0.005), SAT from 572 +/- 151 to 566 +/- 164 cm2 (n.s.) and V/S from 0.29 +/- 0.15 to 0.25 +/- 0.11 (P less than 0.01). Abdominal subcutaneous fat thickness decreased from 36 +/- 8 to 35 +/- 10 mm (n.s.), intra-abdominal thickness from 39 +/- 25 to 20 +/- 20 mm (P less than 0.001) and intra-abdominal/subcutaneous from 1.1 +/- 0.7 to 0.8 +/- 0.6 (P less than 0.005). VAT measurement accurately identified small intra-abdominal fat variations. W/H could not evaluate visceral fat loss, because of simultaneous decreases in waist and hip circumferences. Ultrasound was able to measure small reductions in intra-abdominal fat. 相似文献
998.
The natural killing of K 562 cells by whole blood from normal subjects was comparable with that shown by separated mononuclear cells. In order to establish the conditions for a reliable natural killer assay by using very small numbers of effector cells in whole blood, the isotope uptake of target cells was increased by a modified labelling method, which permitted the use of fewer target cells in the assay. The natural cytotoxicity of whole blood was augmented by interferon to the same extent as observed with separated mononuclear cells. The chemiluminescence of granulocytes in whole blood comparable with that of separated granulocytes. Taken together, these methods are considerably less tedious than the conventional methods, technique is also economical, and the results may reflect in vivo cytolytic processes much better. 相似文献
999.
Deep vein thrombosis is still an underestimated and often unrecognised diseases both in Italy and abroad despite being far from rare and in spite of its severe complications and often disabilitating sequelae. It is a disease which is becoming more frequent due to increased life expectation, the larger number of operations on elderly patients, and the increased frequency of limb injuries. General and specialised surgery is often hampered by this complication. This has raised interest in a more detailed knowledge of the mechanisms leading to DVT, and the correct employment of the latest equipment which enable diagnosis to be made and daily monitoring of the disease during its evolution. But the greatest efforts must be reserved for preventive measures in order to achieve a statistically significant reduction in the incidence of the disease in operated patients. It is to be hoped that a greater awareness of thromboembolic diseases will allow this to be achieved in the future. 相似文献
1000.
Thirteen unrelated patients with idiopathic haemochromatosis (eight men, five women) were studied. The diagnosis was based on clinical, biological, and histochemical findings. HLA typing was performed in all 13 and in all of their available first degree relatives (n = 31). HLA A3 was present in nine of 13 probands (69.2% compared with 18.8% in the group of 53 healthy blood donors and 22.4% in a selected Hungarian population (n = 1910). HLA B7 was present in five of 13 probands (38.4% compared with 11.3% and 14.6%). An A3B7 antigen association was found in five of 13 patients. The A3B7 haplotype was found in three, A2B12 and A2B38 haplotypes were found twice in 10 genotyped probands. Pedigree studies showed that there was one unaffected homozygote, 24 heterozygotes, and six non-carriers. Extended family and population studies are necessary to establish the prevalence of the gene in Hungary and an association with haplotypes other than A3B7. 相似文献