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1.
Adrian Lim Justine Le Clerc 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2019,45(3):414-419
Taurodontism is a rare embryologic anomaly of teeth, defined by an apical displacement of the furcation of roots and enlarged pulp chambers. Taurodontism has been classified as hypo‐, meso‐ or hypertaurodontism according to the severity of the anomaly. The aim of this case report was to illustrate a clinical case with multiple bilateral taurodonts and to describe the endodontic management of the hypertaurodontic mandibular left second molar with a C‐shaped canal and extensive dental pulp calcifications. A healthy 20‐year‐old male patient was referred for the endodontic treatment of his lower left second molar. Cone beam computed tomography revealed a C‐shaped root canal configuration and several dental pulp calcifications in this tooth. The endodontic treatment was performed in two appointments under an operating dental microscope. A panoramic radiograph, made during the 18 months follow‐up appointment, revealed nine other taurodontic molars, most of them associated with dental pulp calcifications. 相似文献
2.
Martha A. Warpehoski Paul J. Buscemi David C. Osborn Birdwell Finlayson Eugene P. Goldberg 《Calcified tissue international》1981,33(1):211-222
Summary The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found
to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter
ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a “growth
front” on stone surfaces with migration of organic material from the “older” interior. The matrix distribution was not readily
correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations
were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich
surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates
as growth centers. 相似文献
3.
4.
K. Singh 《International urogynecology journal》2002,13(1):50-51
The author reports a complicated recurrence of genital tract fistula. The initial vesicovaginal fistula resulted from obstructed
labor, which was subsequently surgically managed without success. The patient had a recurrent vesicovaginal fistula that was
formed by the erosion of vesical stones through the anterior endopelvic fascia into the vagina. The stones eventually eroded
into the rectum, resulting in the formation of a complex vesicovaginal and rectovaginal fistula. 相似文献
5.
305例尿石成份分析及预防对策 总被引:13,自引:3,他引:10
目的研究一种快速、简便的方法对泌尿系结石进行分析,并探讨其防治方法。方法用化学常量法对305例患者的尿石标本进行化学成份测定,并结合临床资料进行分析。结果发现结石发病男性多于女性(比例为3.2∶1),20~50岁多发,上尿路结石多于下尿路结石(5.4∶1)。结石中草酸钙检出率达82%,尿酸盐55.2%,磷酸钙48.6%,磷酸镁铵与碳酸磷灰石则多见于泌尿系感染病例,胱氨酸结石少见。结论化学常量法分析泌尿系结石简便、快捷、准确。结石成份分析对于了解结石成因、预防结石复发具有一定的意义。 相似文献
6.
Summary It has been suggested that urinary sialidase may play a role in the formation of renal stones. The present study was therefore undertaken to compare spectrophotometrically the different types of sialic acid concentrations and sialidase activities in fresh first morning urine specimens of men (21–65 years) with (13) and without (9) calcium oxalate renal stones. Although the free urinary sialic acid concentrations of the two groups of men were statistically about the same (P=0.0614), the total (P=0.003) and bound (P=0.0012) urinary sialic acid concentrations differed significantly. Both the total and bound sialic acid concentrations were lower in the urine specimens of the stone patients than in their healthy counterparts. This decrease in urinary sialic acid concentrations was firstly thought to be the result of elevated breakdown enzymes of sialic acid, which would favour the production of pyruvate. However, spectrophotometric determinations of the endogenous pyruvate concentrations of the two types of urine specimens did not differ significantly (P=0.0708). Secondly, the decrease in total urinary total sialic acid concentration of stone patients, could be attributed to less sialic acid synthesis or less renal excretion. Therefore, the same experiments were repeated using serum of 13 patients and 9 healthy men. Conversely, the total (P=0.4425) and bound (P=0.2850) serum sialic acid concentrations were found to be similar in the two types of subjects. However, the free serum sialic acid concentration of stone patients was significantly lower than in the healthy subjects (P=0.0062). This phenomenon is also reflected in the average ratio for serum free: bound sialic acid in healthy and stone patients, 1:7.9 and 1:18.7 respectively (P=0.0009). The lower free serum sialic acid concentration may lead to lower renal excretions of sialic acid. This may explain the decrease in total urinary sialic acid concentration in stone patients. The lower bound urinary sialic acid concentrations in patients was also reflected in the urinary free: bound sialic acid ratio for healthy (1:2.3) and stone patients (1:1.3). The difference between these two groups of men was highly significant (P=0.0001). This phenomenon might be explained by the urinary sialidase activities, which was spectrophotometrically determined at 334 nm at 37°C of 11 patients with stones and 17 healthy men. The ages of both groups of men were the same (P=0.326). An increase in urinary sialidase activity was observed with the stone patients (P=0.00001) when compared to specimens of healthy men. This might explain the decrease in urinary bound sialic acid concentration of the stone group. It seems from these results that the urinary concentration of sialic acid and the activity of urinary sialidase, may play a role in the pathogenesis of the multifactorial disease, urolithiasis. 相似文献
7.
目的:探讨内镜治疗肝内外胆管残余结石的效果。方法:对1994年1月~2004年1月间306例胆道残余结石的治疗效果进行回顾性分析,采用十二指肠镜127例,胆道镜116例,经皮经肝胆道镜(PTCS)63例。结果:306例.1中有286例成功(93.46%)。十二指肠镜治疗127例成功125例;胆道镜经T管窦道治疗116例,成功109例;PTCS治疗肝内结石63例,成功52例。结论:内镜治疗肝内外胆道结石效果显著,可使绝大多数患者避免再次手术。 相似文献
8.
Hidekazu Mukai Hiroshi Yoshinaga Akihiko Watanabe Hitoshi Fujiwara Tsuyoshi Fujita 《Digestive endoscopy》2004,16(Z1):S58-S61
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting. 相似文献
9.
双频激光碎石在腔镜外科难取性胆管结石中的应用(附23例报告) 总被引:7,自引:3,他引:4
目的探讨双频激光碎石治疗腔镜外科难取性胆管结石的疗效及安全性. 方法 2002年1月~2004年6月,对23例难取性胆管结石进行双频激光碎石治疗.其中腹腔镜胆道探查术中应用14例,术后胆道镜取石中应用9例. 结果 19例取净胆管中结石,结石取净率为82.6%(19/23),无胆管损伤、窦道损伤等并发症. 结论双频激光碎石具有创伤小、效率高、并发症少的优点,对腔镜外科难取性胆管结石是一种可选择的有效方法. 相似文献
10.
E. Croce M. Golia M. Azzola R. Russo L. Crozzoli S. Olmi C. Pompa M. Borzio 《Surgical endoscopy》1996,10(11):1064-1068
Background: Thirty-three patients were candidates for laparoscopic choledochotomy. The indications for this operation are described.
Methods: The procedure was completed 32 times (97%). We had 29 successful common bile duct (CBD) clearances, three negative explorations,
and one failed clearance which needed to be converted to laparotomy. All the completed procedures ended with primary closure
of the main duct. Median duration of surgery was 180 min (range 100–300), including three associated laparoscopic procedures.
Results: There were three postoperative complications (9.4%), none major. Average postoperative hospital stay was 7.1 days (range
4–14). In May–June 1995 we controlled 31 out of the 32 consecutive patients (one patient was lost to follow-up) who had a
successful laparoscopic choledochotomy from October 1991 to December 1994. Median follow-up was 22 months (range 5–44). Besides
clinical control, 23 patients also had ultrasound (US) controls and 24 had blood tests. Eleven had intravenous cholangiotomography.
Two patients died 11 and 22 months after the operation for unrelated causes and without biliary symptoms. Two patients had
umbilical hernias. One had a small residual asymptomatic stone, which was removed endoscopically. None had signs of postoperative
CBD stricture. At US, CBD was ≤7 mm in 15 patients, 8–10 mm in four patients, and 10–12 mm in three patients. The last group
had preoperative CBD dilation, too. We could compare preoperative and postoperative CBD diameters in 22 patients: 11 had no
change; in nine it decreased; and two had a slight increase (8–10 mm).
Conclusions: We conclude that laparoscopic choledochotomy with primary closure is a very good operation: It has a high success rate and
low morbidity. Mortality is nil so far. Medium-term results are very positive: We had no CBD stricture and only one case of
asymptomatic residual stone, which could have been avoided. Our results suggest that intraductal biliary drainage is useless,
and its specific complications are well known.
Received: 20 October 1995/Accepted: 28 February 1996 相似文献