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31.
To examine the effects of transient hyperprolactinemia on in vitro fertilization and embryo transfer, 61 cycles in 50 euprolactinemic ovulatory women with irreparable tubal diseases were stimulated with clomiphene (CC) alone or CC and human menopausal gonadotropin followed by human chorionic gonadotropin (hCG). Serum prolactin (PRL) increased after hCG administration with peak values of 45.4 +/- 4.2 ng/ml on the day of laparoscopic oocyte aspiration. The highest serum estradiol (E2) concentration was found on the day before PRL peak and serum progesterone (P) began to increase after hCG injection concomitant with the PRL rise. The group having 50 ng/ml or more of PRL (34 cycles) had significantly higher levels of E2 during preovulatory and early luteal phase compared to those of the group having less than 50 ng/ml of PRL (27 cycles) but there was no significant difference between the P levels in the two groups. In the higher PRL group 72 (62.1%) of 116 collected oocytes were fertilized and 6 (20.0%) conceived. In the lower PRL group 45 oocytes (58.4%) of 77 were fertilized and 3 (12.5%) became pregnant. These data suggest that elevated serum PRL concentrations may have no effect on fertilization of oocytes in vitro or embryonic development.  相似文献   
32.
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination.  相似文献   
33.
Serial DWIs were performed in a patient with CJD who developed symptoms acutely and progressed rapidly. DWI discloed an increased signal in the frontal and parietal inner cortical areas, and in the caudate nuclei and putamina 20 days after the onset of symptoms. T2-weighted images showed only signal abnormality in the caudate nuclei and putamina, but not in the cerebral cortex. In the CSF obtained 15 days after the onset of symptoms, total tau protein was markedly elevated and 14-3-3 protein was positive. Measurement of these proteins are highly specific and sensitive for the diagnosis of CJD, but not available as a rapid routine examination at present. DWI is not specific, but useful for making the diagnosis of CJD in the early stage of the disease.  相似文献   
34.
Phosphatidylserine is known to significantly accelerate the blood coagulation reaction. In a previous communication submitted for publication, we demonstrated that phosphatidylcholine, phosphatidylethanolamine and lysophosphatidylcholine showed effects on the blood coagulation reaction using the factor Xa-prothrombin reaction system, and discuss a new function of membrane phospholipids. The present study examined the role of phospholipids in the blood coagulation regulatory reaction (anticoagulation system), by studying the effects of phospholipids on the protein C/protein S reaction. We have established quantitative methods for measuring activated protein C activity and protein S activity, and used them to measure their activity after the addition of liposomes with different phospholipid compositions. We found that phosphatidylcholine inhibited activated protein C and protein S activities in a dose-dependent manner, as in the factor Xa-prothrombin reaction system. On the other hand, phosphatidylethanolamine and lysophosphatidylcholine showed no effect on activated protein C activity. Phosphatidylethanolamine inhibited and lysophosphatidylcholine accelerated coagulation activity in the factor Xa-prothrombin system, but such effects were not observed in the protein C/protein S reaction system. The coagulation and anticoagulation reactions are exquisitely balanced by thrombin, with a role both as a procoagulant and anticoagulant. Therefore, it is understandable that phosphatidylethanolamine and lysophosphatidylcholine show different effects in the factor Xa-prothrombin and protein C/protein S reaction systems. It appears that coagulation and anticoagulation reactions are co-ordinated and controlled by changes in phospholipid composition of the cellular membrane where the coagulation reaction takes place.  相似文献   
35.
For intracavitary high dose-rate radiation therapy, a thermoluminescent [TL] sheet for in vivo measurement of spatial dose distribution around source has been recently developed. The TL sheet was found to have a linear response with a very wide dynamic range from at least 0.002 cGy to 5000 cGy for 60Co gamma-rays. This TL sheet (40 cm x 50 cm x 200 microns), which is composed of Teflon mixed with BaSO4:Eu doped powder, is very flexible and can be cut to the desired size. In addition, this sheet is easy to handle because of its insensitivity to room light. The spatial dose distribution is displayed in a color mode by using a newly developed TL sheet readout system. For a clinical application, the TL sheet was wrapped on an applicator for intracavitary radiation therapy of a rectal cancer and was inserted into the rectum. The location of the TL sheet could be confirmed with diagnostic X ray film. After irradiation with high dose-rate 60Co source, the in vivo relative dose distribution on the surface of the rectum was determined. This TL sheet provided a convenient means of measuring the relative dose distributions around 60Co sources of various patterns in intracavitary radiation therapy.  相似文献   
36.
37.
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
38.
目的 探讨胞嘧啶脱氨酶(cytimidine deaminase,CD)基因修饰神经干细胞及其基因表达。方法 通过构建真核表达质粒pCMVCD,限制性内切酶消化鉴定后,采用Lipofectamine 2000脂质体介导法转染新生大鼠室管膜下区神经干细胞(Neural stem cells,NSCs),G418筛选阳性克隆,加入不同浓度的5-氟胞嘧啶(5-Flourocytosine,5-FC),MTT比色法测定NSCs的生存率。结果 本实验成功地培养并鉴定了神经干细胞,并将CD基因成功地转染了神经干细胞,G418阳性NSCs对低浓度5-FC高度敏感。结论 CD基因修饰神经干细胞的离体实验研究为干细胞治疗研究提供依据。  相似文献   
39.
A 17-year-old male patient with Marfan syndrome was admitted due to recurrent bilateral pneumothorax which had recurred totally 11 times during the past 3 years. For the treatment of obstinately continuing right pneumothorax resection of bullae in combination with pleuropexy using OK 432 was effective. Two months thereafter Bentall operation with a composite graft consisting of a woven Dacron tube and a Bj?rk-Shiley 27 mm aortic valve prosthesis was performed for his anuloartic ectasia. Left pneumothorax recurred 2 weeks after Bentall operation. But it was treated successfully with OK 432 injection into the left pleural cavity. Now, he is doing well as a student.  相似文献   
40.
Primary leiomyosarcoma of the thyroid gland   总被引:1,自引:0,他引:1  
Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically, the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be essential in the treatment of this rare but rather aggressive malignancy.  相似文献   
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