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961.
962.
Growth hormone (GH) is known to accelerate spermatogenesis and maintain gonadal function. In this study, we evaluated the effect of GH on recovery from testicular damage induced by cyclophosphamide (CP). Eleven- to fourteen-week-old GH-deficient Lewis rats (dw/dw) were divided into 4 groups (n = 10 each), with one group serving as controls. In the CP group, CP was intravenously administered in daily doses of 50 mg/kg for 2 days, followed by daily doses of 10 mg/kg for the next 3 days. In the GH group, rat GH was subcutaneously administered at a daily dose of 0.3 mg/kg until the rats were sacrificed. In the CP/GH group, GH and CP administration were started simultaneously. In the CP/preGH group, GH administration was started 14 days before CP administration. Five rats from each group were sacrificed at days 14 and 28 after administration of CP. Spermatogenesis was then evaluated morphometrically by counting numbers of cells at several stages of the spermatogenic cycle. On day 14, there were no significant differences in the numbers of the spermatocytes between CP and CP/GH group. On day 28, the numbers of spermatocytes and motility of spermatozoa in CP/GH group were greater than those of CP group were. In the CP/preGH group, these effects of GH administration were not observed. These results suggested that administration of GH improved testicular function damaged by CP under GH-deficient condition, when GH and CP administration are started simultaneously.  相似文献   
963.
Gitelman syndrome is a renal disorder characterized by hypokalemia, hypomagnesemia, metabolic alkalosis and hypocalciuria due to the defective tubular reabsorption of magnesium and potassium. This disease is caused by mutations of thiazide-sensitive Na-Cl cotransporter (TSC) gene. Gitelman syndrome is usually distinguished from Bartter syndrome by the presence of both hypomagnesemia and hypocalciuria. However, a phenotypic overlap is sometimes observed. We encountered two sporadic Japanese patients with Gitelman syndrome and analyzed their TSC gene. These patients were diagnosed as Gitelman syndrome by the typical clinical findings and biochemical abnormalities, such as mild muscular weakness, periodic paralysis, tetany, metabolic alkalosis, hypomagnesemia and hypocalciuria. In patient 1, a novel two base deletion (del TG at nucleotide 731 and 732) in exon 5 and a two base deletion (del TT at nucleotide 2543 and 2544) in exon 21 previously reported in a Japanese patient were identified. The patient 2 had a missense mutation (L623P), that was also identified in Japanese patients, and a novel in-frame 18 base insertion in exon 6 as a heterozygous state. Family analysis of two patients confirmed an autosomal recessive inheritance. In conclusion, we add two new mutations of the TSC gene in Japanese patients with Gitelman syndrome. Because the differential diagnosis between Bartter syndrome and Gitelman syndrome is sometimes difficult, molecular analysis would be a useful diagnostic tool, particularly in unusual cases with phenotypic overlapping.  相似文献   
964.
OBJECT: Although previous studies reported that late reperfusion might prevent left ventricular dilation after acute myocardial infarction (AMI), implication of persistent ischemic chest pain on admission remains to be investigated. This study was undertaken to assess the implication of persistent ischemic chest pain on in-hospital outcome and left ventricular function after late reperfused AMI. METHODS AND PATIENTS: We studied 63 patients with a first anterior AMI who underwent percutaneous coronary intervention 6 to 24 hours (11.2+/-4.5 hours) after the onset. Of 63 patients, 48 (76%) had persistent ischemic chest pain on admission. RESULTS: Incidence of in-hospital death, reinfarction or congestive heart failure was similar between the 2 groups. Pretreatment left ventricular ejection fraction and end-diastolic volume were similar between the 2 groups. Predischarge angiography was performed at 17+/-5 days after the onset. Late reperfusion prevented the dilation of left ventricular end-diastolic volume in patients with chest pain (78+/-12 to 75+/-17 ml/m2, p=0.15), but did not in those without (75+/-20 to 93+/-28 ml/m2, p=0.03). A multivariate analysis revealed that absence of persistent ischemic chest pain was an independent predictor of predischarge left ventricular end-diastolic volume >100 ml/m2 (odds ratio 0.10, p=0.04). CONCLUSIONS: Our data demonstrated that absence of persistent ischemic chest pain appears to be a simple and reliable marker which predicts left ventricular dilation after late reperfused AMI.  相似文献   
965.
966.
We have established a method for in situ tissue engineering of the stomach in a canine model using an acellular collagen scaffold graft. The current study was conducted to evaluate the functional aspects of the tissue-engineered stomach wall. The anterior wall of the stomach in beagle dogs was replaced with a collagen sponge scaffold measuring 4 x 4 cm. At 16 weeks after implantation, the animals were sacrificed and the stomach specimens were evaluated immunohistochemically and physiologically. Regeneration of the proton pump and thin muscle layer, which are essential for mechanical and chemical digestion by the stomach, was observed in the tissue-engineered gastric tissue. However, acetylcholine-induced contraction was not observed in the tissue-engineered stomach wall. Although there is still room for improvement, the tissue-engineered stomach wall had a highly organized structure, and it is anticipated that this approach could eventually become an alternative for stomach reconstruction after gastrectomy.  相似文献   
967.
This report concerns a series of 12 patients with simple bone cysts of the calcaneus, who were treated between 1988 and 2000 by a minimal surgical intervention of curettage, multiple drilling and continuous decompression through insertion of a cannulated screw. Inserted screws were made of titanium in 8 cases and ceramics in 4 cases. The mean operative time was 58.8 +/- 25.4 minutes, and complete healing was achieved in 11 cases after 9.2 +/- 6.4 months. One patient needed an additional surgery for replacement of a titanium screw. Final results were excellent after a mean follow up of 91 +/- 52.1 months. This series of patients represents one of the largest reported series of calcaneal simple bone cyst in conjunction with long-term follow-up. Our technique of minimal curettage, drilling and continuous decompression with a cannulated screw insertion is considered to be a good option for management of simple bone cysts of the calcaneus.  相似文献   
968.
OBJECTIVE: The employment of surgical microscopy in the field of neurosurgery has significantly contributed not only to the advancement of surgical technique, but also the operative outcome as well. This technology has allowed surgeons to meet the demands for increasingly difficult levels of surgery, which usually require a long operative time. However, the surgeon and the assistant are restricted in their posture for a long time, leading to excessive muscular and ocular stress. To solve these problems, we have developed and clinically applied a three dimensional video microscope system for surgery, using a two binocular camera method, that allows surgical procedures to be performed over a video monitor. METHOD: Two 3CCD cameras were installed on the assistant's lens attachment and the camera lens attachment of the microscope for neurosurgery, manufactured by Carl Zeiss Co., Ltd. The surgery was performed by viewing the three dimensional picture on the monitor, which was created by processing the images from the cameras by a time-division method. In November 1998, the prototype was completed and, with numerous modifications, its clinical application has become possible. Currently, we have used it in 42 clinical cases. RESULTS: 1) Instead of viewing the surgical field through a conventional surgical microscope, the surgeon and the assistant were able to perform microsurgery by viewing the stereoscopic vision on the video monitor, through polarized glasses. 2) The assistant is provided with a separate video monitor, so that the assistant can freely adjust the angle of vision 90-180 degrees, according to where he stands. 3) The nurses, resident surgeons and students can view the same three dimensional images displayed to the surgeon. This effectively contributes to the educational environment. CONCLUSION: Even during a long surgical procedure, the posture of surgeon and assistant became less restricted since there was no need to look through the eyepiece of the microscope and led to significant decrease in physical fatigue and ocular strain. In the 42 clinical trials, the operation proceeded uneventfully, without any serious complications.  相似文献   
969.
Aortic arch injections according to Theron's method have been performed in patients with cerebral ischemia. Digital subtraction angiograms with modified windowing (low and narrow) have been used for better visualization of cerebral parenchymal condition. This "cerebral parenchymography" allows much easier understanding of cerebral parenchymal vascularization on angiographic imaging. Although further study is necessary to estimate accurate cerebral blood flow, this technique can enable an easy and quick understanding of the overall cerebral hemodynamics.  相似文献   
970.
We report three cases of radiation-induced carotid arterial stenosis that underwent successful angioplasty with stenting. The patients had received radiation therapy for tongue or laryngeal cancers and developed minor completed strokes 6 to 14 years after irradiation. All patients had multiple and bilateral stenosis, measuring more than 50%, of the carotid arteries. The stenosis was located in the internal, external, and common carotid arteries. We performed percutaneous transluminal angioplasty with stenting. All interventions were successful and carotid stenosis decreased to less than 28%. No permanent complications occurred. During follow-up periods of up to 26 months, all of these cases were free from ischemic symptoms. Neither carotid angiography nor ultrasound sonography showed evidence of restenosis. The present results suggest the usefulness of angioplasty with stenting for radiation-induced carotid arterial stenosis.  相似文献   
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