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51.
Ito N Nomura S Iwase A Ito T Ino K Nagasaka T Tsujimoto M Kobayashi M Mizutani S 《Early human development》2003,71(1):29-37
AIMS: Membrane-bound aminopeptidases in human placenta are thought to be involved in maintaining homeostasis during pregnancy by metabolizing bioactive peptides such as oxytocin and angiotensin at the interface between the fetus and mother. Because determining the precise localization of these enzymes is required to support this notion, we investigated the ultrastructural localization of two principal enzymes, aminopeptidase A (APA; EC 3.4.11.7)/angiotensinase and placental leucine aminopeptidase (P-LAP; EC 3.4.11.3)/oxytocinase in human first trimester and full-term placenta. METHODS: Immunohistochemical analysis using anti-P-LAP and anti-APA antibodies was performed on ultrathin frozen sections of fixed human placental villi. RESULTS: Transmission immunoelectron microscopy revealed that both enzymes were expressed on the surface of apical microvilli of syncytiotrophoblast cells and, to a lesser extent, on the basal infoldings. The location of the two enzymes did not vary between the first trimester and full-term placenta sections, while the staining intensities were slightly enhanced in full-term villi. CONCLUSIONS: Our observation that P-LAP and APA are present on the microvilli, which is a site of interaction between the mother and fetus, suggests possible involvement of these enzymes in cleaving peptide hormones from the fetus and mother in order to regulate bioactivity. 相似文献
52.
Okamoto T Niu R Mizutani S Yamada S 《American journal of obstetrics and gynecology》2003,188(1):135-140
OBJECTIVE: The aim of the current study was to investigate levels of placenta growth factor in the tissues and sera of the patients with gestational trophoblastic disease and to determine its usefulness for the treatment of gestational trophoblastic disease. STUDY DESIGN: Placenta growth factor concentrations were measured in the tissue homogenates of 12 normal placentas, 33 complete hydatidiform moles, and 6 gestational choriocarcinomas. Serum placenta growth factor levels were determined in 59 women with normal pregnant course, in 30 women with complete hydatidiform mole, in 36 women with persistent gestational trophoblastic disease, and 100 nonpregnant healthy volunteers. RESULTS: Serum and tissue placenta growth factor levels in the patients with mole tended to be decreased compared with the levels in normal pregnancy; the levels were increased significantly in patients with choriocarcinoma. When serum placenta growth factor levels were >20 pg/mL (normal upper limit in nonpregnant women), placenta growth factor-to-human chorionic gonadotropin ratios were increased significantly in patients with persistent gestational trophoblastic disease. CONCLUSION: Serum placenta growth factor levels are not of any predictive value in patients with hydatidiform mole. However, elevated serum placenta growth factor levels with increased placenta growth factor-to-human chorionic gonadotropin ratios are suggestive of persistent gestational trophoblastic disease. 相似文献
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Mimura T Funatsu H Uchigata Y Kitano S Noma H Shimizu E Konno Y Amano S Araie M Yoshino O Iwamoto Y Hori S 《American journal of ophthalmology》2003,135(6):844-848
PURPOSE: To investigate the relationship between human leukocyte antigen (HLA) status and proliferative diabetic retinopathy (PDR) to assess the genetic basis of PDR in younger type 1 diabetic patients. DESIGN: Retrospective, nonrandomized, comparative trial. METHOD: Patients who were diagnosed with type 1 diabetes under 30 years of age (range, 13-28) and had a disease duration of more than 10 years were studied. The patients were divided into two groups: 30 patients who had undergone vitreous surgery younger than 40 years old (the PDR group) and 50 patients without retinopathy (the non-DR group). The duration of diabetes and the level of glycemic control were matched between the two groups. The control group consisted of 50 healthy patients. HLA-A, -B, -C, -DR, and -DQ typing of blood samples was done using the standard microcytotoxicity method. RESULTS: The frequency of HLA-B62, Cw4, and DQ4 was significantly higher in the PDR group than in the non-DR group (P =.0020, P =.048, and P =.0026, respectively). The Cw4-DR4-DQ4 haplotype frequency was significantly higher in the PDR group than in the control group and the non-DR group (P =.0059). CONCLUSIONS: Our results suggests that HLA-B62, Cw4, and DQ4 may be useful for predicting the prognosis of retinopathy in patients with younger-onset type 1 diabetes. 相似文献
55.
It is important that all images in a picture archiving and communication system (PACS) environment should be stored in the correct location, e.g., in the proper patient's folder. However, if patient information, such as identification number or patient name, has been entered incorrectly, the image may be stored in the wrong place. We are developing an automated patient recognition method for chest radiographs based on a template-matching technique to prevent such filing errors. To further improve the performance of our method, we investigated the usefulness of a new automated patient-recognition method based on a template-matching technique by using edge-enhanced and smoothed images. We found that the relationship between the correlation values obtained with and without the edge-enhancement technique tended to provide different criteria for identifying correct or incorrect patients. When we combined the two methods to distinguish the images by a rule-based method, 67.1% of wrongly identified patients in our database could be identified as wrongly identified, without any false warnings for correctly identified patients. We consider that this automated method for patient recognition based on edge-enhanced images would be useful in preventing "wrong" images from being stored in a PACS environment. 相似文献
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57.
Goto H Shimada Y Tanikawa K Sato S Hikiami H Sekiya N Terasawa K 《The American journal of Chinese medicine》2003,31(2):267-275
We studied the effect of traditional herbal medicines containing daio (Rhei Rhizoma) on the long-term progression of diabetic nephropathy with overt proteinuria in eight patients [mean age 60 (45-73) years; duration of diabetes 18 (7-36) years]. At the beginning of the study, mean HbA1c was 8.2% and mean serum creatinine was 1.0 +/- 0.3 mg/dl. Everypatient had diabetic neuropathy and retinopathy. Three of the patients had hypertension and four had ischemic heart disease. After 107 +/- 25 months, the mean serum creatinine level had significantly increased to 4.8 +/- 2.6 mg/dl. The mean serum creatinine levels of five patients not advancing to dialysis treatment increased from 1.2 +/- 0.3 to 3.2 +/- 1.0 mg/dl, and the three patients requiring dialysis increased from 0.8 +/- 0.1 to 7.5 +/- 2.1 mg/dl. In the control group, treated without traditional herbal medicines, the mean serum creatinine level had significantly increased from 1.0 +/- 0.3 to 9.5 +/- 1.9 mg/dl after 71 +/- 12 months. All of the control group required dialysis treatment. Diabetic nephropathy with overt proteinuria is reported to develop into renal failure after 6-7 years. In this retrospective study, traditional herbal medicines with Daio were considered to be effective in prolonging the pre-dialysis period of diabetic nephropathy. 相似文献
58.
Prepancreatic Postduodenal Portal Vein: Report of a Case 总被引:1,自引:0,他引:1
Inoue M Taenaka N Nishimura S Kawamura T Aki T Yamaki K Enomoto H Kosaka K Yoshikawa K 《Surgery today》2003,33(12):956-959
We report an unusual case of a prepancreatic postduodenal portal vein (PPPV), incidentally discovered during total gastrectomy. If it had not been noticed, this portal vein might have been ligated and divided with disastrous consequences. This anomaly was not diagnosed preoperatively, but it could have been. Although embryological anomalies of the portal venous system, such as PPPV and preduodenal portal vein, are rarely encountered in abdominal surgery, surgeons must be aware of their possibility and be able to recognize them to avoid major intraoperative injury. 相似文献
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