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Meckel's diverticulum, which is a remnant of the omphalomesenteric or vitelline duct, is the most common congenital abnormality of the gastrointestinal system. Urachal abnormalities, resulting from anomalous urogenital development, are not observed frequently and case reports are mainly represented in literature. The presence of these two congenital anomalies together is a very rare pathology. Complications arising from a Meckel's diverticulum or urachal remnant may clinically mimic acute appendicitis and other surgical pathologies. We report on a patient who underwent surgery for acute appendicitis when it was discovered that the symptoms were produced by a perforated Meckel's diverticulitis. In the course of the surgery, a urachal remnant was found to coexist with the diverticulum.  相似文献   
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Acutely increased intra-abdominal pressure (IAP) can lead to multiple organ failure. As blood flow to intra-abdominal organs is reduced by high venous resistance, ischemia-reperfusion (I/R) injury plays an important role in the pathogenesis of abdominal compartment syndrome (ACS) following IAP. Melatonin, a secretory product of the pineal gland, is known to have free radical scavenging and antioxidative properties in several oxidative processes. The objective of this study was to examine the potential protective properties of melatonin on the oxidative organ damage in a rat model of ACS. Under ketamine anesthesia, an arterial catheter was inserted intraperioneally (i.p.) and using an aneroid manometer connected to the catheter, IAP was kept at 20 mmHg (ischemia group; I) for 1 hr. In the ischemia/reperfusion (I/R) group, pressure applied for an hour was decompressed and a 1-hr reperfusion period was allowed. In another IR group, melatonin was administered (10 mg/kg, i.p.) immediately before the decompression of IAP. The results demonstrate that tissue levels of malondialdehyde (MDA) and myeloperoxidase activity (MPO; index of tissue neutrophil infiltration) were elevated, while glutathione (GSH; a key to antioxidant) levels were reduced in both I and I/R groups (P < 0.05-0.001). Melatonin treatment in I/R rats reversed these changes (P < 0.01-0.001). Moreover, melatonin given to the I/R group reduced the elevations in serum aspartate aminotransferase, alanine aminotransferase and blood urea nitrogen levels and abolished the increase in serum creatinine levels. Our results indicate that melatonin, because of antioxidant and free radical scavenging properties, ameliorates reperfusion-induced oxidative organ damage. In conclusion, the results of the present study suggest that the therapeutic value of melatonin as a 'reperfusion injury-limiting' agent must be considered in ACS.  相似文献   
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Infection by the intestinal nematode parasite Nematospiroides dubius was studied in seven different inbred mouse strains. Although there was some minor variation in the susceptibility of the different strains to a primary infection there were marked differences in their ability to develop resistance to infection following repeated exposure to infective larvae. The strains of mice which developed the best resistance also expelled adult worms arising from the previous infections. The adult worms resulting from a primary infection were slowly eliminated in two inbred strains studied whereas no loss occurred from outbred LACA mice. Although males and females of two strains, C3H/HeJ and CBA/H were equally susceptible to a primary infection, the females developed better resistance than the male mice following two oral administrations of third stage larvae. Infected mice of every strain and both sexes contained high levels of IgG1 in the serum.  相似文献   
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PURPOSE: This study evaluated the surface microhardness and flexural and compressive strengths of five luting cements and compared the degree of conversion of dual and autopolymerized forms of four resin-based luting cements. MATERIALS AND METHODS: Four resin composite luting cements-Panavia F, Variolink 2, RelyX Unicem Applicap, and RelyX ARC-and a polycarboxylate cement (Durelon, control group) were used in three-point bending, compression, and Vickers hardness tests following water storage for 1 week. Resin composite cements were additionally investigated with both dual and autopolymerization techniques under Fourier transformed infrared spectroscopy. Differences were analyzed using one-way ANOVA. RESULTS: The highest flexural strengths were obtained with Variolink 2 (90 MPa, SD 22), whereas the lowest were observed with Durelon (28 MPa, SD 4). RelyX Unicem showed the highest hardness values (44 HV, SD 5), whereas Variolink 2 gave the lowest (32 HV, SD 6). The highest compressive strengths were obtained with RelyX Unicem (145 MPa, SD 32), whereas the lowest were observed with Durelon (41 MPa, SD 17). For both dual and autopolymerized groups, RelyX ARC showed the highest degrees of conversion (81% and 61%, respectively) and RelyX Unicem had the lowest (56% and 26%, respectively). CONCLUSION: Resin composite luting cements of similar chemical characterizations differed in their physical properties, and polymerization method influenced their degree of conversion.  相似文献   
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PURPOSE: To evaluate our experience with the LithoTron lithotripter (Healthtronics, Atlanta, GA), a dry portable system that utilizes a spark-gap electrode as an energy source. PATIENTS AND METHODS: We prospectively evaluated the first 312 treatments performed on 199 men and 99 women with an average age of 43.5 years (range 4 months-80 years), over a 25-month period between May 1999 and June 2001. Of the 468 stones treated, 136 were located in the ureter, 52 in the renal pelvis or ureteropelvic junction, and 230 in the kidney; the sites of 50 were not specified in our database. The average stone size was 8.0 mm (range 1-40 mm). Follow-up included a plain (KUB) film, CT scan, or intravenous urogram (IVU) and was available for 256 patients. "Stone free" was defined as no fragments visible on postoperative images. The mean radiographic follow-up was 74 days (range 0-866 days). Data collection was initially done manually by data sheets, but a Web-based medical database application was developed in order to enter, store, retrieve, and analyze the data more efficiently. RESULTS: The average number of shocks delivered per renal unit was 2689 at 25.8 kV. Seventy-five percent of the procedures were performed with intravenous sedation. Two thirds (169/256) of the patients were rendered stone free with one treatment. According to size, 71% (209/294) of stones <1 cm, 57% (39/68) of stones between 1.0 and 1.5 cm, and 22% (8/36) of stones >1.5 cm were eliminated. There were 23 patients who required further treatment; from the available data, 18 of them are currently stone free. Perioperative complications occurred in 6 patients (2%). No patient had worsening renal function or new-onset hypertension. The effectiveness quotient was 59.3%. CONCLUSION: The LithoTron lithotripter is satisfactory for stones <1 cm.  相似文献   
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The purpose of this study was to determine the prevalence and correlates of attempted suicide among young injection drug users (IDUs) from six study sites in five US cities. Two thousand two hundred and nineteen participants 15-30 years of age underwent interviewer-administered questionnaires relating to self-reported drug use, sociodemographics, suicidal ideation and attempts, and exposure to violence. The 6-month prevalence of suicidal ideation and attempts was 35.8% (n = 795) and 7% (n = 156), respectively. Compared to those not reporting a recent (past 6 months) suicide attempt, those attempting suicide were more likely to have a lifetime history of mental health facility admission or sexual abuse. Participants receiving drug treatment at the time of the baseline interview (53.2% versus 37.1%, odds ratio [OR] = 1.93, 95% confidence interval [CI]: 1.39, 2.67) were also more likely to report a recent attempt; as were those reporting a history of experiencing violence. These associations persisted after adjusting for age, sex, race/ethnicity, study site, and other significant covariates by multiple logistic regression. These data suggest that increased access to drug treatment, community mental health, and violence prevention programs may decrease suicidal behavior among young injection drug users.  相似文献   
10.
骨骼肌缺血再灌注损伤及发病机制初探   总被引:4,自引:1,他引:3  
张俐  Seaber AV  Urbaniak JR 《中国骨伤》2001,14(11):667-670
目的:探讨骨骼肌缺血再灌注损伤过程的微循环变化。组织学改变以及多肽含量变化和意义。方法:42只雄性大鼠随机分为留伴行神经组和去伴行神经组,建立标准骨骼肌缺血再灌注模型,采用激光多谱勒及显微放大分析系统,组织学方法以及凝胶电泳方法等观察缺血再灌注损伤变化。结果:缺血再灌注损伤后的骨骼肌微血管管径在20分钟时恢复率基本达到高峰约60%,此后为平台期:90分钟最高峰,为75%,主干血管流速率亦在20分钟基本达到上限,病理检查显示:缺血的骨骼肌纤维呈空泡状,核形态增大,染色加深,红细胞严重聚集,凝胶蛋白电泳提示:缺血骨骼肌中分子量20KD左右的多肽显著增加。结论:骨骼肌缺血再灌注损伤发生后,骨骼肌的微循环发生不同程度的破坏,及因之导致骨骼结构损伤和异常的20KD多肽含量明显增加,以及红细胞凝聚,白细胞的改变,这些共同构成了缺血再灌注损伤机制。  相似文献   
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