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71.
72.
Hysteroscopic findings of two cases with homologous type of malignant mixed müllerian tumor of the corpus uteri are described. On hysteroscopic examination, not only were nodular or polypoid lesions with fairly smooth surfaces found but also lesions with rough uneven surfaces and dilated vessels resembling the figures of endometrial carcinoma were observed. The blood vessels of lesions with fairly smooth surfaces were not dilated. Under hysteroscopy, each lesion with a smooth surface seemed to be more closely related to a benign lesion, such as an endometrial polyp or submucous myoma. The lesions with smooth surfaces corresponded to the histologically sarcoma-dominant areas and the lesions with uneven surfaces and dilated vessels were equivalent to the sites where adenocarcinoma was noted. Thus, hysteroscopic findings of this tumor well reflected the histology near the surface of the endometrium.  相似文献   
73.
Some techniques for the treatment of mandibular protrusion with consideration for aesthetic improvement of the face as a whole are described. The aesthetic inferiority complex in the mind of patients with masticatory disorders as the chief complaint should not be underestimated. Three techniques were used in this study; preoperative orthodontic treatment, preservation of the patient's self-image, and maintenance of beautiful relationship between the midfacial line and the nasolabial fold as well as the nasal ala.  相似文献   
74.
For the purpose of immunological study on small intestinal transplantation (SIT), rat SIT models using direct suture technique widely have been used, which requires at least several months of training for microsurgery. Alternatively, a simple cuff technique for SIT has been mainly used by us, which reduces warm-ischemic time and the training period, but the entire intestinal grafts usually obtain a limited blood supply. This report describes a modification of a combined cuff and suture technique for rat SIT to aid beginning microsurgical transplantation researchers. The advantages are 1) use of only arterial suturing, making it easier for beginners, with the cuff technique applied to the more difficult vein anastomosis; 2) achievement of better arterial inflow and graft survival than when the arterial cuff technique is used; and 3) doing only partial clamping of the aorta, which improves animal survival and success of the procedure. A very high successful rate in orthotopic whole SIT was achieved even by beginners.  相似文献   
75.
Multiple genetic and epigenetic alterations in oncogenes, tumor-suppressor genes, cell-cycle regulators, cell adhesion molecules and DNA repair genes, as well as genetic instability and telomerase activation, are responsible for tumor genesis and progression of gastric cancer. The scenario of these epigenetic alterations found in gastric cancer differs, depending on the two types of gastric cancer, indicating that there are at least two types of CpG (cytidine phosphate guanosine) island methylator phenotypes in the intestinal-type and diffuse-type of gastric cancer. In addition to promoter methylation, acetylated histone H4 is obviously reduced in a majority of gastric carcinoma. Histone H4 is progressively deacetylated from the early stage (precancerous lesions) to the late stage (invasion and metastasis) in gastric carcinogenesis. Since there is no difference in the level of acetylated histone H4 between the intestinal-type and diffuse-type of gastric cancer, histone H4 deacetylation may be involved in both types of gastric cancer. This article proposes histone acetylation and retinoic acid receptor beta DNA methylation as novel targets for gastric cancer therapy. (c) 2002 Prous Science. All rights reserved.  相似文献   
76.
Aged (27 months of age) and young (6 months of age) Fischer 344/DuCrj rats were exposed to gamma-ray irradiation, and their livers were compared for levels of oxidative DNA modifications and repair enzyme activities. The amounts of 8-oxo-2'-deoxyguanosine (8-oxodG) in the nuclear DNA of the livers of both young and aged rats increased immediately after irradiation, by 1.7-fold in the livers of young rats and 2.7-fold in the livers of the aged rats. Also, the rate of 8-oxodG decay was slower in the livers of the aged rats than in young rat liver, and remained above the baseline level even 1 week after irradiation. The activities of 8-oxodG-releasing enzymes peaked 2 and 6 h after irradiation in the livers of young and aged rats, respectively. The repair activity in the livers of the young rats was increased by sevenfold 2 h after irradiation, while the livers of the aged rats showed a twofold increase 6 h after irradiation. These results suggest that the ability to repair damaged DNA is lower in aged rats, and that the accumulation of oxidative DNA damage that takes place during aging may be related to this decline in repair activity.  相似文献   
77.
Cardiac lymphangioma is uncommon and constitutes one of the rare forms of cardiac diseases. A 6-year-old girl had an abnormal electrocardiogram in a screening test on admission to an elementary school. Echocardiogram, computed tomogram, and magnetic resonance imaging showed a mediastinal multicystic mass that was adjacent to the left ventricle of the heart. The tumor was found to be originated in myocardium by left thoracotomy and pericadiotomy. A partial resection of tumor and a pericardial window were done. This case, to the authors' knowledge, represents the sixth reported case of cardiac lymphangioma. J Pediatr Surg 37:E32.  相似文献   
78.
The peroxisome proliferator-activated receptor (PPAR) gamma is an important regulator of adipocyte differentiation and a modulator of intracellular insulin-signaling events. We examined the roles of the Pro12Ala variant of PPAR gamma2 in obesity and insulin resistance in 402 Japanese patients with type 2 diabetes and 116 control subjects. Among the diabetes subjects, the Pro12Pro homozygotes showed significantly higher body mass index (BMI) than those with the Pro12Ala variant (p = 0.020), while there was no association between genotype and BMI in the controls. Furthermore, diabetic subjects with Pro12Pro showed significantly higher fat body mass index (FBMI) than those with Pro12Ala (p = 0.016), while no association between genotype and lean body mass index (LBMI) was observed. Regarding insulin resistance, there was no difference in the HOMA index or in clamp index between Pro12Ala and Pro12Pro variants. These data suggest that the Pro12Ala polymorphism of PPAR gamma2 does not influence insulin resistance but body composition in Japanese diabetic subjects.  相似文献   
79.
OBJECTIVES: Appropriate management of renal trauma is still controversial. Many of the patients have minor injuries and conservative treatment can achieve excellent outcomes without any complications. For major injuries of deep lacerations or ruptures, we have been performing early surgical treatment to salvage the kidney in the selected cases after the precise evaluation of the injury. To obtain the optimal management options, we evaluated the clinical results of our procedures. PATIENTS AND METHODS: We conducted a retrospective study, which included 106 cases of blunt renal trauma with evident etiology over the past 22 years and 9 months. The severity of the injury was evaluated mainly by CT scanning. The indication of renal exploration included persistent renal bleeding, large hematoma around the kidney, dislocated fragments, nonviable tissue, massive urinary extravasation and vascular injury. With the patients who required an operation, we first controlled the bleeding by clamping the hilar vessels. Then, the final decision whether to repair or remove the kidney was made based on the direct inspection of the injured kidney after the complete removal of the hematoma. The severity of renal trauma was classified by the classifications found in The Organ Injury Committee of the American Association for the Surgery of Trauma. RESULTS: Sixty-three patients were managed conservatively without any interventions, while 22 surgical repairs and 21 nephrectomies were performed. Of the 63 patients, 35 patients (81.4%) were operated on within 2 days after the injury. Judging from systolic blood pressure, red cell count, blood loss during surgery and transfusion requirements, surgically treated patients were more severely injured than conservatively treated patients. And nephrectomized patients than surgically repaired patients. All the surgically repaired cases were confirmed to have preserved renal functions postoperatively. In all of the 50 patients with Grade I injuries, conservative treatment was successful. Eight out of the 19 Grade II and III cases, who were indicated for kidney exploration because of multiple lacerations or considerable bleeding, were also successfully repaired. Localized hematoma with no urine leakage, even when it was large, settled spontaneously without complication. For the 37 Grade IV and V injuries, including 4 cases with hilar injuries, we implemented conservative procedures on 2 patients, surgical repair on 14 patients and nephrectomy on 21 patients. In the conservatively treated cases, one deep laceration with relatively large, but localized, hematoma, and minimal urine extravasation healed spontaneously. Atrophy of the segment and hypertension developed in the other ruptured kidney with dislocated fragments, large hematoma and urine leakage. This kidney, which also required later surgical exploration, did have good parenchymal blood flow. Hilar injury cases were all resulted in nephrectomy. CONCLUSION: In most of our cases the indication for surgical exploration or nephrectomy based on our criteria seemed to be properly decided. Several cases, though, might have received overtreatment. Recent advances in evaluations and strategies of renal trauma have decreased the need for surgical exploration. This may have overreached the indication for conservative management. Severely injured kidneys may be managed conservatively because in most cases bleeding settles after the full formation of large hematoma within the Gerota's fascia. In such cases, though, no one can predict whether the injury will heal spontaneously or not, and, moreover, whether a complication will develop or not. We think that the optimal management of the patient requires an accurate evaluation of the injured kidney. Therefore the indication for surgical exploration should be made based on the degree of the injury.  相似文献   
80.
Background. Unlike the many chemotherapeutic agents that do not effectively stop blood flow or induce necrosis in hepatocellular carcinoma, AC-7700 has been shown to inhibit tubulin polymerization and selectively stop tumor blood flow. The aim of this study was to elucidate the antivascular and antitumor effects of AC-7700 on rat hepatoma. Methods. AH-130 cells, a rat hepatoma cell line, were solidified and implanted into the liver of Donryu rats. Vascularity of the liver tumor was directly identified by in-vivo fluorescence microscopy from 0 to 60 min after the injection of 10 mg/kg AC-7700. To observe the antivascular effect of AC-7700, the vascular density of the tumor was measured and assessed as the ratio of preinjection to postinjection values. The antitumor effects were evaluated with histopathologic findings and analysis of animal survival. Results. In-vivo microscopic observation showed that tumor perfusion diminished within 30 min after AC-7700 administration. Vascular density in the AC-7700 group was significantly less than that in the control group at 60 min (AC-7700, 26.3 ± 16.4%; control, 88.5 ± 9.2%; P < 0.001). After AC-7700 injection, marked necrosis of tumor cells was observed histologically, and tumor area was decreased significantly (AC-7700, 11.5 ± 15.4 mm2; control, 43.5 ± 18.3 mm2; P < 0.05). The survival rate (50%) of the AC-7700 group animals was better than that of the control group (0%; P < 0.01). Conclusion. Markedly decreased tumor perfusion was induced by AC-7700 within 30 min, and this decrease may have contributed to the tumor necrosis and favorable outcome in the treatment group. AC-7700 appears to be a promising agent for the treatment of hepatocellular carcinoma. Received: September 14, 2001 / Accepted: February 21, 2002  相似文献   
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