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61.
Ionic currents in single smooth muscle cells of the human vas deferens   总被引:1,自引:0,他引:1  
PURPOSE: Smooth muscle cells of the vas deferens have an important role in carrying sperms to the exterior but little is known of their electrophysiological properties. We characterized the voltage-gated ion channel currents in single smooth muscle cells of the human vas deferens (HVSMCs). MATERIALS AND METHODS: We observed contractile responses of 8 circular smooth muscle strips of the human vas deferens to a high concentration (10 mM) of tetraethylammonium. HVSMCs were isolated using proteolytic enzymes (collagenase and papain), and were used for an electro-physiological study using whole cell and inside-out patch clamp configurations. RESULTS: The application of 10 mM tetraethylammonium induced rhythmic contractions of the strips. When HVSMCs were dialyzed with a KCl solution, step depolarizations of membrane potential evoked oscillatory outward K currents that were not inactivated. The large conductance Ca activated K (BKCa) and delayed rectifier components of the outward current were identified. The BKCa channel showed a large single channel conductance (162.7 +/- 13.2 pS with 5 mM K in the patch pipette). Two types of Ca currents were identified in the whole cell configuration. With a cell held at -50 mV an L-type Ca current was present during a depolarizing step pulse. From a holding potential of -90mV L-type and T-type Ca currents were elicited by depolarizing step pulses. CONCLUSIONS: HVSMCs have 2 (L and T) types of Ca channels and 2 types of K (BKCa and delayed rectifier) channels. Voltage dependent changes of these ion channels and their interactions may be important in regulating vas contractility.  相似文献   
62.
To validate the adverse effects of subluxation of the femoral head in Legg-Calve-Perthes disease, the authors made an experimental model of Perthes disease with subluxation in growing rabbits by interrupting the epiphyseal artery (devascularization) and immobilizing the knee in extension (immobilization). Seventy-two rabbits, 4 to 5 weeks old, were divided into three groups: group A with both devascularization and immobilization (25 rabbits), group B with devascularization only (25 rabbits), and group C with immobilization only (22 rabbits). In each experimental group, four to six rabbits each were killed at 1, 2, 4, 8, and 12 weeks. After reviewing the serial radiographs and gross specimens, the authors found six radiologic and six macroscopic abnormalities. The incidence and the severity of deformity in group A rabbits were higher than that of groups B or C in terms of the overall incidence of deformities (P <0.001), head deformity scores (P <0.001), and the incidence of a total collapse of the capital femoral epiphysis. In conclusion, subluxation of the immature femoral head with avascular necrosis in rabbits increased femoral head deformities.  相似文献   
63.

Background

Various techniques for endoscopic thyroidectomy have been introduced in the past decade, and the cosmetic superiority of these techniques has been universally acknowledged. We developed the endoscopic thyroidectomy via bilateral axillo-breast approach (BABA) and have performed more than 500 operations. The aims of this study are to analyze the surgical outcomes and to evaluate the effectiveness and safety of BABA endoscopic thyroidectomy.

Patients and methods

Between February 2004 and March 2008, 512 patients with thyroid diseases underwent BABA endoscopic thyroidectomy. The criteria analyzed were clinicopathologic characteristics, types of operation, operation time, tumor–node–metastasis (TNM) stage on the basis of the 7th edition of the American Joint Committee on Cancer (AJCC), results after radioactive ablation therapy, and recurrence of disease in these patients.

Results

Of 512 patients, 397 had a malignant tumor and 115 had benign thyroid disease. Eight patients were diagnosed with Graves’ disease, and nine patients underwent completion thyroidectomy. Three cases were subjected to open thyroidectomy due to uncontrolled bleeding. Mean operation time was 151.2?±?38.1?min for total and near-total thyroidectomy, and 141.7?±?50.1?min for subtotal thyroidectomy and lobectomy. Regarding postoperative complications, transient hypocalcemia occurred in 31.1% of patients and permanent hypoparathyroidism occurred in 4.2% of patients. Transient hoarseness occurred in 20.3% of patients, and permanent vocal cord palsy occurred in 1.7%. Mean hospital stay after operation was 3.34?±?0.8?days (range 3–7?days), and mean follow-up period was 57.1?±?17.6?months (range 38.5–71.7?months). There were eight cases of recurrent thyroid carcinoma, and no mortality has occurred up to the present time.

Conclusions

Endoscopic thyroidectomy via bilateral axillo-breast approach is a safe and effective method that gives good surgical completeness, a low rate of postoperative complications and recurrence, and an excellent cosmetic result. Therefore, this method is a good choice for patients with surgical thyroid diseases.  相似文献   
64.
Jeong O  Cho SB  Joo YE  Ryu SY  Park YK 《Surgical endoscopy》2012,26(6):1778-1783

Background

Knowledge of the intraoperative location of lesions is a prerequisite for deciding the proper extent of gastric resection or the choice of anastomosis technique during totally laparoscopic distal gastrectomy (TLDG) for early gastric cancer (EGC). In this study we introduce a novel tumor localization method for TLDG: endoscopic blood tattooing.

Methods

Twenty-three consecutive patients scheduled for TLDG for EGC were enrolled in this prospective study. The day before surgery, 2–3?ml of autologous blood was injected into the gastric muscle layer at 3–4?cm proximal to the lesion during endoscopy.

Results

The study subjects consisted of 15 males and 8 females with a mean age of 61?±?10.4?years. During surgery, the endoscopic blood tattooed sites were successfully identified in all 23 patients. No complications associated with the procedure occurred, and no patient had microscopic residual tumor cells at the proximal resection margin, with a mean proximal margin length of 3.3?±?2.7?cm. Eighteen patients underwent TLDG with Billroth II anastomosis, four patients with Roux-en-Y gastrojejunostomy, and one patient with laparoscopic total gastrectomy. At final pathologic examinations, 20 patients were of stage IA and 3 were of stage IB according to the UICC TNM classification (6th ed.).

Conclusions

Endoscopic blood tattooing provides a simple and useful means of localizing lesions during TLDG for EGC. Although the superiority of this technique over other localization methods needs to be evaluated further, the authors recommend endoscopic blood tattooing as an alternative to other intraoperative localization methods for laparoscopic surgery for EGC.  相似文献   
65.

Background

We evaluated vascular patency and potential changes in preserved spleens after laparoscopic spleen-preserving distal pancreatectomy (SPDP) with conservation of both splenic vessels.

Methods

We retrospectively analyzed the patency of conserved splenic vessels in patients who underwent laparoscopic or robotic splenic vessel-conserving SPDP from January 2006 to August 2010. The patency of the conserved splenic vessels was evaluated by abdominal computed tomography and classified into three grades according to the degree of severity.

Results

Among 30 patients with splenic vessel-conserving laparoscopic SPDP, 29 patients with complete follow-up data were included in this study. During the follow-up period (median: 13.2?months), grades 1 and 2 splenic arterial obliteration were observed in one patient each. A total of five patients (17.2%) showed grade 1 or 2 obliteration in conserved splenic veins. Most patients (82.8%) had patent conserved splenic vein. Four patients (13.8%) eventually developed collateral venous vessels around gastric fundus and reserved spleen, but no spleen infarction was found, and none presented clinical relevant symptoms, such as variceal bleeding. There was no statistical difference in vascular patency between the laparoscopic and robotic groups (P?>?0.05).

Conclusions

Most patients showed intact vascular patency in conserved splenic vessels and no secondary changes in the preserved spleen after laparoscopic splenic vessel-conserving SPDP.  相似文献   
66.

Purpose  

The clinical importance of intraductal papillary mucinous neoplasm of the pancreas (IPMN) has been increasing with a large number of newly diagnosed IPMN. This study was designed to explore the characteristics of resected IPMN and to determine the predictive factors for malignant and invasive IPMN.  相似文献   
67.
Lim BJ  Jeong JY  Chang YK  Na KR  Lee KW  Shin YT  Choi DE 《Renal failure》2012,34(7):892-900
Although cisplatin is a highly effective antineoplastic agent, nephrotoxicity is its major clinical problem. Recently, it was reported that Spirulina, a blue-green algae, has potent antioxidant properties. The aim of this study was to establish the possible protective role of C-phycocyanin (PC), one of the active ingredients of Spirulina, against cisplatin-induced nephrotoxicity. This study was carried out using human kidney-2 (HK-2) cells and male C57BL6 mice. Cells and mice were divided into four groups; untreated control group, PC-treated control group, cisplatin-treated group, and PC plus cisplatin-treated group. The molecular, functional, and structural parameters were measured. PC significantly attenuated blood urea nitrogen, serum creatinine, renal histological damages, and apoptotic cell death in cisplatin-treated mice. The cisplatin-induced cell death was significantly attenuated in cells pretreated with PC. PC also significantly attenuated the elevation of p-ERK, p-JNK, and p-p38 induced by cisplatin treatment. The expression of Bax, caspase-9, and caspase-3 in cisplatin-treated cells were also decreased by PC treatment. In conclusion, PC ameliorates cisplatin-induced nephrotoxicity and, at least in part, suppression of p-ERK, p-JNK, p-p38, Bax, caspase-9, and caspase-3 may be involved in this mechanism.  相似文献   
68.
Streptococcus dysgalactiae subspecies dysgalactiae (SDSD), Lancefield group C streptococcus, is an animal pathogen which often causes pyogenic infection in domestic animals. Human infection by SDSD has been reported as a cellulitis on the upper arm, but a prosthetic joint infection caused by SDSD after total knee arthroplasty (TKA) has not yet been reported in the literature demonstrating that its clinical manifestation and management have not been well established. In this case report, we aimed to present a case of SDSD prosthetic joint infection after TKA, which was successfully treated by two-stage re-implantation with an application of antibiotic-impregnated cement spacer.  相似文献   
69.
Perforation of the ureter is a rare condition that causes a series of problems including retroperitoneal urinoma, urosepsis, abscess formation, infection, and subsequent renal impairment. There are causative factors that induce ureteric rupture, including malignancy, urinary calculi, idiopathic retroperitoneal fibrosis, recent iatrogenic manipulation, external trauma, degenerative kidney conditions, urography with external compression, and spontaneous causes. We report a rare case of ureteric rupture caused by urinary retention. The patient was treated with temporary percutaneous drainage and antibiotics. The present case illustrates that urinary retention can induce not only bladder rupture, but also ureteric rupture. It is thus of paramount importance to effectively manage patients with voiding problems.  相似文献   
70.

Background

The purpose of this study was to investigate whether preoperative liver stiffness measurement (LSM) can predict recurrence after curative resection of hepatocellular carcinoma (HCC). LSM using FibroScan? can assess the severity of liver fibrosis, which is significantly associated with recurrence after curative resection of HCC.

Methods

Between February 2006 and March 2009, 133 patients who underwent preoperative LSM and curative resection for HCC were enrolled in this prospective study. LSM values were analyzed for association with recurrence, together with other clinical variables.

Results

The mean age of the patients (117 men and 16 women) was 57?years. During the follow-up period (median, 25.0 (range, 3.0?C54.6) months), HCC recurred in 62 (46.6?%) patients. In multivariate analysis, together with satellite nodule and Edmonson-Steiner grade III?CIV, LSM was selected as an independent predictor of recurrence (P?<?0.05; hazard ratio, 1.034; 95?% confidence interval, 1.007?C1.061). When the study population was stratified into two groups using the optimal cutoff value (13.4?kPa) that maximized the sum of sensitivity (64.7?%) and specificity (76.1?%) from time-dependent receiver operating characteristic curves (area under the receiver operating characteristic curve?=?0.676), patients with LSM values >13.4?kPa were at a significantly greater risk for recurrence with a hazard ratio of 1.925 (P?=?0.01; 95?% confidence interval, 1.17?C3.168) compared with those with LSM values ??13.4?kPa.

Conclusions

Our data suggest that LSM can be a useful predictor of recurrence after curative resection of HCC.  相似文献   
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