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91.

Background

Evidence supporting routine surgery for asymptomatic tethered cord in patients with anorectal malformation (ARM) is, at best, speculative. The authors therefore examined whether untethering is indicated for asymptomatic tethered cord in patients with ARM.

Methods

A retrospective analysis of all patients with ARM (n = 223) between 1992 and 2002 was conducted. During the same period, 435 patients had surgery for tethered cord.

Results

Tethered cord was detected radiologically in 22 (9.8%); 8 patients with a low conus, and 14 with a low conus with and thickened filum. Seven of 22 patients underwent untethering; 3 prophylatic (14%) and 4 for neuro/motor function deficits (18%). All 4 symptomatic patients had significant clinical improvement in their neuro/motor functions after surgery. However, bowel and urinary functions remained unchanged in all 7 patients with a mean follow-up of 6.4 years (range, 4 to 8 years). Fifteen patients with radiologically diagnosed tethered cord remain asymptomatic with a mean follow-up of 2.7 years (range, 8 months to 10 years).

Conclusions

Neuro/motor functions clearly improved with surgery in symptomatic patients. However, bowel and urinary functions remained unchanged after surgery. Only 4 ARM patients with tethered cord required surgery, whereas prophylactic surgery appears to have minimal benefit. Expectant conservative approach in the management of asymptomatic tethered cord patient appears to be safe.  相似文献   
92.
PURPOSE: We describe our experience with transvaginal total pelvic reconstruction using a mesh with 4-point fixation for patients with genitourinary prolapse with or without stress urinary incontinence. MATERIALS AND METHODS: A total of 29 consecutive patients who underwent sacrospinous fixation using mesh material since March 1999 for genitourinary prolapse were analyzed retrospectively. In all patients defect specific repair was done, including hysterectomy (in 13). For isolated vault prolapse a rectangular mesh was interposed between the peritoneum and vaginal vault, with each corner anchored to the sacrospinous ligament using a suture-capturing device. For vault prolapse associated with anterior vaginal wall prolapse an "H" shaped, 1-piece sling was used to support both entities. Additionally, posterior and perineal repairs were done through separate incisions if needed. RESULTS: Of the 29 patients 19 (65.5%), 7 (26.92%) and 11 (39.29%) had associated symptoms of stress urinary incontinence, urgency and frequency, respectively, and 79.31% had associated anterior and 44.8% had associated posterior prolapse. Average operative time was 175.6 minutes, blood loss was 340 cc and hospital stay was 2.46 days. Early adverse events following the procedure were perineal pain, vaginal discharge and irritative voiding symptoms. At 6 month followup (mean 25.14 months) mild constipation and dyspareunia were encountered in a small subset of patients. Two patients (6.89%) have genital prolapse recurrence and none has reported erosion or nonhealing to date. CONCLUSIONS: Transvaginal technique of 4-point vaginal vault fixation using mesh is a safe and effective procedure at 2 years.  相似文献   
93.
Introduction: Recent studies of patients with colorectal cancer have suggested a shift towards the proximal colon and an increase in the incidence of right sided colon cancer. This study aimed to determine the anatomical distribution of colorectal cancer over a 10 year period in a district general hospital. Methods: Records of patients diagnosed with primary colorectal cancer from 1993 to 2002 were reviewed for demographic data, histology subtype, and anatomical location of the tumour. Tumours located at and proximal to the splenic flexure were defined as right sided cancer and tumours arising distal to the splenic flexure were defined as left sided cancer. Results: A total of 763 patients were included in the study, of whom all had adenocarcinoma and 99% were white. Sixty nine percent of cancers were left sided and 31% were right sided. Although there was a 4% increase in the proportion of right sided cancers, there was no statistically significant increase using logistic regression analysis. Mann-Whitney U test revealed no significant difference in age at diagnosis between the right and left sided cancers. Although a higher proportion of females were diagnosed with right sided cancer compared with left sided cancer, this was not statistically significant. Conclusion: The anatomical distribution of colorectal cancer has been fairly stable at this hospital with no evidence of a shift towards the proximal colon. No differences were identified in the tumour distribution with respect to gender and age at diagnosis. Our findings support the initial application of flexible sigmoidoscopy for investigating patients with suspected colorectal malignancy and follow up colonoscopy for selected patients to exclude right sided pathology.  相似文献   
94.
Recently, we found sesame to be a major cause of severe IgE-mediated food allergic reactions among infants and young children in Israel. The purpose of this study was to describe the different patterns of sesame sensitivity. We have identified three subgroups among our patients (n = 32). Group I (n = 23, M/F; 14/9) consisted of cases with IgE-mediated sesame allergy. The mean age of the first allergic reaction was 11.7 months. Although the main clinical manifestation was urticaria/angiedema (n = 14, 60%), anaphylaxis was the presenting symptom in seven (30%) patients; all of them were younger than 1 year. Sixteen (70%) were found to be allergic to other foods, and other atopic diseases were identified in 18 (78%) patients. Three patients 'outgrew' their allergy within 1–2 years. Group II (n = 2) included cases in whom sesame allergy was ruled out based on a negative skin prick test (SPT) together with a negative open oral challenge. Group III (n = 7) consisted of patients that were found to be SPT positive for sesame as part of a screening for other food allergies. Although sesame products have become fashionable in westernized countries, early exposure may cause sesame to share eventually the same 'noteriety and fate' as peanut – a major cause of severe food allergic reactions.  相似文献   
95.
The T cell antigen receptor complexes expressed on alphabeta and gammadelta T cells differ not only in their respective clonotypic heterodimers but also in the subunit composition of their CD3 complexes. The gammadelta T cell receptors (TCRs) expressed on ex vivo gammadelta T cells lack CD3delta, whereas alphabeta TCRs contain CD3delta. While this result correlates with the phenotype of CD3delta(-/-) mice, in which gammadelta T cell development is unaffected, it is inconsistent with the results of previous studies reporting that CD3delta is a component of the gammadelta TCR. Since earlier studies examined the subunit composition of gammadelta TCRs expressed on activated and expanded peripheral gammadelta T cells or gammadelta TCR(+) intestinal intraepithelial lymphocytes, we hypothesized that activation and expansion may lead to changes in the CD3 subunit composition of the gammadelta TCR. Here, we report that activation and expansion do in fact result in the inclusion of a protein, comparable in mass and mobility to CD3delta, in the gammadelta TCR. Further analyses revealed that this protein is not CD3delta, but instead is a differentially glycosylated form of CD3gamma. These results provide further evidence for a major difference in the subunit composition of alphabeta- and gammadelta TCR complexes and raise the possibility that modification of CD3gamma may have important functional consequences in activated gammadelta T cells.  相似文献   
96.
97.
PURPOSE: Unilateral ureteral obstruction (UUO) for 21 hours causes severe renal vasoconstriction. We examined the role of endothelin (ET)-A receptor in renal hemodynamic alterations induced by UUO. MATERIALS AND METHODS: Hemodynamic and clearance experiments were performed in 3 groups of anesthetized dogs. In group 1, 6 sham operated dogs received intrarenal infusion of the specific ET-A receptor antagonist BQ-610 (Peninsula Laboratories, Inc., Belmont, California), followed by infusion of the nitric oxide synthase substrate L-arginine. In the 7 group 2 dogs release of 21-hour UUO was followed by intrarenal infusion of BQ-610 and L-arginine. In the 5 group 3 dogs release of 21-hour UUO was followed by L-arginine infusion. RESULTS: UUO caused marked decreases in renal blood flow (RBF) and glomerular filtration rate (GFR) in groups 2 and 3 compared with group 1. In group 1 BQ-610 and L-arginine infusion did not alter RBF or GFR. In contrast, BQ-610 infusion in group 2 after UUO release led to a significant increase in RBF and GFR as well as additional increases after L-arginine infusion. After UUO release in group 3 L-arginine infusion alone did not change RBF or GFR. CONCLUSIONS: After UUO release blockade of the ET-A receptor ameliorates renal vasoconstriction. The addition of L-arginine, which is a substrate for nitric oxide synthase, superimposed on ET-A receptor blockade confers a further decrease in renal vascular resistance, suggesting that the ET and L-arginine-nitric oxide systems are involved in renal hemodynamic alterations caused by UUO.  相似文献   
98.
We describe the case of a 62-year-old man with recent onset of constitutional symptoms and vague intellectual deficit. The blood showed pancytopenia with blastemia, and bone marrow confirmed an extensive "vacuolated blast-like cell" infiltrate. Initial diagnosis of, and treatment for Burkitt's leukemia/lymphoma was questioned when the "blasts" typed as CD5+ mature B-cells; however, it was revised to intravascular lymphoma (IVL) only after the sinusoidal pattern was confirmed by immunocytochemistry. Literature review indicated that blood and bone marrow involvement in IVL appears to be rare, but a systematic search for this involvement is often not carried out. CD5 expression has been increasingly reported in this disease. The actual frequency and the significance of this expression are still to be defined.  相似文献   
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