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61.
PCNA immunostaining combined with AgNOR staining in esophageal squamous cell carcinoma to identify patients with a poor prognosis 总被引:6,自引:0,他引:6
Yoshihisa Morisaki Shingo Shima Yutaka Yoshizumi Yoshiaki Sugiura Susumu Tanaka Seiichi Tamai 《Surgery today》1995,25(5):389-395
Immunostaining of the proliferating cell nuclear antigen (PCNA) provides important information about cell kinetics and is easily performed on routinely obtained formalin-fixed, paraffin-embedded materials. We report herein the results of a retrospective study on PCNA staining in esophageal cancer undertaken to determine its significance. As this study indicated that immunoreactivity was preserved in specimens fixed within 24 h, only 31 specimens from surgical patients were available for this investigation. The mean PCNA index of the patients without invasion to the adventitia (35.7±17.9) was significantly lower than that of those with invasion to the adventitia or neighboring structures (49.7±14.5), while the PCNA index did not correlate with other clinicopathologic parameters such as histologic type, lymph node metastases, or prognosis. However, when an analysis of PCNA staining was combined with an analysis of argyrophilic nucleolar organizer region (AgNOR) staining, a correlation with prognosis was found. In fact, seven patients with a high PCNA index (44) and AgNOR count (6) had a significantly poorer prognosis than the remaining 22 (P=0.0014), and six of these seven patients died within 2 years. These results indicate that this combined evaluation may be useful for the identification of patients with a poor prognosis among those undergoing surgery for esophageal squamous cell carcinoma. 相似文献
62.
Purpose. To investigate the role of phospholipase A2 (PLA2) in reperfusion injury of the kidney in an in vivo animal model, renal mitochondrial PLA2 activity was measured under three different conditions.
Methods. Male Wistar rats (n = 72) anesthetized with pentobarbital underwent renal ischemia surgically for 45 min and were reperfused for the indicated
time (renal ischemia/reperfusion). Treatments included reperfusion for various predetermined periods (phase 1), exposure to
hyperbaric oxygen (phase 2), and administration of reactive oxygen species (ROS) scavenger (phase 3). Thereafter, each kidney
was harvested, and mitochondrial PLA2 activity was measured by a radioisotope technique.
Results. Ischemia/reperfusion resulted in time-related PLA2 activation in the renal mitochondria up to 48 h of reperfusion after renal ischemia. Renal mitochondrial PLA2 activity was further augmented by hyperbaric oxygen exposure prior to reperfusion, whereas administration of the ROS scavengers
suppressed mitochondrial PLA2 activity.
Conclusion. These data suggest that ROS may play an important role in the in vivo activation of PLA2 associated with renal ischemia/reperfusion.
Received for publication on July 6, 1998; accepted on November 30, 1998 相似文献
63.
Total Esophagectomy versus Proximal Esophagectomy for Esophageal Cancer at the Cervicothoracic Junction 总被引:1,自引:0,他引:1
Fujita H Kakegawa T Yamana H Sueyoshi S Hikita S Mine T Tanaka Y Ishikawa H Shirouzu K Mori K Inoue Y Tanabe HY Kiyokawa K Tai Y Inutsuka H 《World journal of surgery》1999,23(5):486-491
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic
junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two
groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy
with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy
resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy
compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy
(total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different
between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper
mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or
without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients. 相似文献
64.
Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma 总被引:2,自引:0,他引:2
Tomita G Niwa Y Shinohara H Hayashi N Yamamoto T Kitazawa Y 《International ophthalmology》1999,23(1):3-10
Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow.
Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve. 相似文献
65.
66.
Breast conserving surgery and radiation therapy (RT) can achieve a more favorable cosmetic outcome than mastectomy in patients with early breast cancer. However, it is widely recognized that RT is an impediment to improving the cosmetic outcome. Between 1985 and 1993, 113 patients were enrolled in a prospective randomized study to examine whether or not RT could be avoided following sector resection in patients with Stage I and II (UICC) invasive breast cancer. There was no significant difference in the 8 year local recurrence free survival rate between the RT and non-RT groups (92.3% versus 89.8% respectively). The characteristics of suitable patients would be negative nodes and microscopically negative resection margins. In conclusion, sector resection without RT is a reasonable option for some patients with early breast cancer. 相似文献
67.
Tetsuo Hadama Yoshiaki Mori Osamu Shigemitsu Tatsunori Kimura Shinji Miyamoto Hidenori Sako Tooru Soeda Toshihide Yoshimatsu Yuzo Uchida 《Surgery today》1996,26(1):60-63
We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system. 相似文献
68.
Makoto Komura Yoshiaki Tsuchida Toshiro Honna Yoshiyuki Kamii Shu-ichiro Kitahara Shin-pachi Ishizone 《Pediatric surgery international》1993,8(2):157-161
A case showing many of the typical visceral features of cloacal exstrophy is reported. The patient had fn imperforate anus, a cecal-cloacal fistula, dehiscence of the pubiic symphysis, and lumbosacral spina bifida with synsingomyelia, but the lower abdominal wall was intact without any visceral extroversion. The pertinent literature was reviewed, and it was found that this case corresponded to t typical case of completely covered cloacal exstrophy. Only six cases, including the present one, have so far been reported in the literature. From a clinical viewpoint, it apparently occupies an intermediate position in the wide spectrum of cloacal anomalies between classical cloacal exstrophy and imperforate anus with recto-cloacal fistula, but anatomatically and embryologically it is definitely a variant of cloacal exstrophy. In other words, it looks like an imperforate anus with recto-cloacal exstrophy, but should be treated as a variant of loacal exstrophy. The anatomy, classification, embryology, diagnosis, and management of this peculiar surgical condition are discussed, and recognition of this entity is urged. 相似文献
69.
Tomohiro Odaka Yoshiaki Watanabe Sunao Moriguchi Kouhei Akazawa Mituo Simada Maki Sakamoto Taturo Kamakura Yoshiaki Nose 《Journal of medical systems》1991,15(3):221-227
We constructed a micro-mainframe-link clinical research system for personal use (Personal Clinical Research System). This system was developed with both a mainframe computer and a personal computer (PC). The prepared programs included a database manager (on the mainframe computer), a user interface program (on the PC), and a communication control program that connected the mainframe computer with the PC. The database on the mainframe computer was constructed by two methods. The first method was to transmit data from the PC to the mainframe computer. The second method was to extract data from the patient information database. Using this system, a physician is able to construct a personal research database that contains interesting data for the physician. In addition, the physician is able to accumulate data on a special field using this system. A discharge summary system is now in operation as an example of this system. 相似文献
70.
Local blood flow of the bowel wall was measured by hydrogen clearance method both in the muscular and submucosal layers in the mongrel dog, separately and concurrently. A platinum wire electrode with a bare tip of 0.5 mm in length and 0.2 mm in diameter was inserted into each layer. About 10 per cent hydrogen gas was inhalated directly through the side hole attached to the endotracheal tube for 1–2 minutes and the obtained clearance curves were plotted on the semi-logarithmic scale, which was almost monoexponential. The results obtained were as follows:
- Mean basal perfusion rate of the muscular layer of the intestine was 0.81–0.92 ml/min/gm, whereas that of the submucosal layer was 1.29–1.31 ml/min/gm, respectively. There was little difference of perfusion rates between the small and the large intestine. The results showed good correlationship with those reported by other authors.
- The effect of vasoactive substances such as vasoconstrictor and vasodilator on the local blood flow in the bowel wall was confirmed.
- This method is repeatedly applicable for measurement and also renders the information on the distribution of blood flow in the splanchnic area.