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991.
992.
Watanabe T Yamada H Morimura Y Abe M Motoyama T Sato A 《The journal of obstetrics and gynaecology research》2008,34(3):418-421
Ovarian Sertoli-Leydig cell tumors (SLCT) are rare sex cord stromal neoplasms. To date there have been approximately 25 case reports of ovarian SLCT expressing alpha-fetoprotein (AFP). In such cases, AFP was immunohistochemically detected in the Sertoli cells, Leydig cells, or hepatocytes. This case report confirms heterologous gastrointestinal epithelium expression of AFP. A 20-year-old woman presented with complaints of abdominal enlargement and irregular menstrual cycles over one year. A right ovarian tumor was detected and the patient's serum AFP was elevated. A right salpingo-oophorectomy was performed. On microscopic examination, the tumor was composed of a fibrosarcoma-like area and a poorly differentiated SLCT area with heterologous gastrointestinal epithelium. Immunohistochemical analysis detected AFP in the gastrointestinal epithelium only. Postoperatively, serum AFP levels fell to normal. A recurrent tumor was discovered in the omentum after adjuvant chemotherapy, but serum AFP remained normal. A second laparotomy was performed and the recurrent tumor showed only fibrosarcoma-like features. The patient received second line chemotherapy and is currently in remission. This is the first case of AFP production by heterologous gastrointestinal epithelium in SLCT. 相似文献
993.
994.
995.
Takahiko Sakuma Yuji Higashibata Hirohisa Kawahata Shuichi Yamada Masaru Okabe Yukihiko Kitamura Shintaro Nomura 《Journal of orthopaedic science》2003,8(3):361-366
Osteopontin is a sialoprotein that is expressed in various cells. It plays a variety of important roles in cell adhesion,
migration, signaling, calcification, and immunity. Its diverse functions indicate that the regulation of osteopontin may also
vary extensively among tissues. Although osteopontin promoter has been studied in vitro, in vivo analyses may be more appropriate
for elucidating osteopontin's functions. In an attempt to investigate osteopontin gene expression, we generated transgenic
mice in which the bacterial β-galactosidase reporter gene was conjugated downstream of osteopontin promoter. The osteopontin
promoter was a mouse −910 bp upstream fragment, which we had previously found functional in 3T3 cells. Among 34 transgenic
founders, 13 mice were transgenic, as determined with the polymerase chain reaction. Osteopontin and β-galactosidase signals
were evaluated with in situ hybridization. Among the 13 transgenic mice, 3 were β-galactosidase-positive. In these transgenic
mice, osteopontin signals were observed in bones and kidneys, whereas β-galactosidase message was detected only in bones.
This suggests that the −910 bp osteopontin promoter is active in bones but not in kidneys. These data imply that the promoter
region required for osteopontin expression in kidneys may differ from that in bones.
Received: March 22, 2002 / Accepted: December 5, 2002
RID="*"
ID="*" Offprint requests to: T. Sakuma
Acknowledgments. We greatly appreciate the excellent histotechnological assistance of Mr. Kenji Morihana. This work was supported in part
by a grant from The Ministry of Education, Science, and Culture, Japan (no. 12470056). 相似文献
996.
997.
V. Pathiraja V. Villani M. Tasaki A. J. Matar R. Duran‐Struuck R. Yamada S. G. Moran E. S. Clayman J. Hanekamp A. Shimizu D. H. Sachs C. A. Huang K. Yamada 《American journal of transplantation》2017,17(1):91-102
We previously reported that transplantation (Tx) of prevascularized donor islets as composite islet‐kidneys (IK) reversed diabetic hyperglycemia in both miniature swine and baboons. In order to enhance this strategy's potential clinical applicability, we have now combined this approach with hematopoietic stem cell (HSC) Tx in an attempt to induce tolerance in nonhuman primates. IKs were prepared by isolating islets from 70% partial pancreatectomies and injecting them beneath the autologous renal capsule of five rhesus monkey donors at least 3 months before allogeneic IK Tx. HSC Tx was performed after mobilization and leukapheresis of the donors and conditioning of the recipients with total body irradiation, T cell depletion, and cyclosporine. One IK was harvested for histologic analysis and four were transplanted into diabetic recipients. IK Tx was performed either 20–22 (n = 3) or 208 (n = 1) days after HSC Tx. All animals accepted IKs without rejection. All recipients required >20 U/day insulin before IK Tx to maintain <200 mg/dL, whereas after IK Tx, three animals required minimal doses of insulin (1–3 U/day) and one animal was insulin free. These results constitute a proof‐of‐principle that this IK tolerance strategy may provide a cure for both end‐stage renal disease and diabetes without the need for immunosuppression. 相似文献
998.
Pathogenesis of idiopathic scoliosis. Experimental study in rats. 总被引:19,自引:0,他引:19
STUDY DESIGN: A radiographic examination of pinealectomized rats to observe the development of scoliosis and halt the condition by administration of melatonin. OBJECTIVES: To discover whether pinealectomy has the same effect in mammals as shown in the chicken, and to determine whether the bipedal condition is important for development of scoliosis. SUMMARY OF BACKGROUND DATA: Pinealectomizing chickens shortly after hatching consistently resulted in scoliosis closely resembling human idiopathic scoliosis. It has not been determined whether this phenomenon is restricted solely to chickens, or if this experimental model is applicable to other animals, especially those more closely related to humans. METHODS: A sham operation in five bipedal rats served as the control in this study. Pinealectomy was performed in 10 quadrupedal rats, pinealectomy in 20 bipedal rats, and pinealectomy with implantation of melatonin pellet in 10 bipedal rats. Spinal radiographs were used to measure the degree of scoliosis at 3 months after surgery. RESULTS: Scoliosis developed only in pinealectomized bipedal rats and not in quadrupedal rats. It developed in none of the sham operation group and in only 1 of 10 pinealectomized bipedal rats with melatonin treatment. CONCLUSIONS: Melatonin deficiency secondary to pinealectomy alone does not produce scoliosis if the quadrupedal condition is maintained. The bipedal condition, such as that in chickens or humans, plays an important role in the development of scoliosis. The findings suggest a critical influence of a postural mechanism for the development of scoliosis. 相似文献
999.
Correlation between spinal cord blood flow and arterial diameter following acute spinal cord injury in rats 总被引:3,自引:0,他引:3
Summary Simultaneous measurements of spinal cord blood flow and arterial diameter at areas adjacent to a site of spinal cord injury were carried out to determine changes in CO2 reactivity and autoregulation. The spinal cord injury was made at T10 level by the epidural clip compression method. A spinal window was drilled at an area either 7 mm caudal or 7 mm rostral to the injury site for the measurement of spinal cord blood flow and arterial diameter at the same time. Spinal cord blood flow was decreased at both spinal windows, especially at the rostral window. Arterial diameter was also decreased significantly at both sites. The ischaemic zone evaluated histologically tended to expand more diffusely in the rostral direction than in the caudal direction.In the pre-injury stage, both CO2 reactivity and autoregulation were present in the spinal cord. Following the clip injury, CO2 reactivity and autoregulation were both impaired in the areas 7 mm adjacent to the impact site. Correlation coefficients suggested that the rostral spinal cord tended to sustain more injury than the caudal spinal cord.The histologically proven spinal cord ischaemia following the injury may have resulted from the decreased arterial diameter and impaired CO2 reactivity and dysautoregulation of the spinal cord. 相似文献
1000.
Mitsumasa Hata M. Shiono Y. Orime K. Nakata A. Sezai H. Yamada T. Saito Y. Sezai 《Artificial organs》1996,20(5):678-680
Abstract: To estimate coronary microcirculation during left heart bypass (LHB), we performed an experimental comparison study of LHB and intraaortic balloon pumping (1ABP). LHB was performed with a BioMedicus BP-80 pump supporting half of the flow of cardiac output whereas the IABP was pumped in a 1:1 mode for cardiogenic shock in a swine model. Coronary circulations were analyzed by electromagnetic flowmeter, pulsed Doppler velocimeter, and laser Doppler flowmeter. Left ventricular end-diastolic pressure (LVEDP) was reduced significantly by LHB. Although there was no significant difference in epicardial flow between the LHB and IABP groups, endocardial flow was increased significantly by LHB. In the LHB group, the systolic reverse wave of the coronary velocity called a myocardial invalid circulation was reduced remarkably. There was a significant inverse correlation between endocardial flow and LVEDP. These results suggested that LHB was more effective for myocardial microcirculation than was IABP. 相似文献