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51.
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53.
In an attempt to immortalize the gene products of single neurons, somatic cell hybrids were produced by fusion of embryonic rat dorsal root ganglion (DRG) neurons with mouse neuroblastoma cells. Embryonic day 13 rat DRGs were fused with mouse neuroblastoma cells deficient in hypoxanthine phosphoribosyltransferase (HPRT; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8). The hybrid cells were selected in medium with 100 microM hypoxanthine/1 microM aminopterin/12 microM thymidine to eliminate the neuroblastoma cells and with cis-hydroxyproline to retard fibroblast growth. Of the 17 lines derived, 4 manifested neuronal properties and were cloned. These lines retain both rat and mouse chromosomes and synthesize characteristic rat and mouse isoenzymes. Neuronal gangliosides, action potentials, and extensive neurite-like processes are exhibited by these hybrid cells, properties characteristic of DRG neurons but not of the neuroblastoma parent. Each line manifests a unique combination of action-potential properties and cell-surface markers, suggesting the selective expression of subsets of DRG neuronal genes. All of these neuronal properties are expressed constitutively, without the need for chemical induction or mitotic inhibition, and stably, without diminution after at least 5 months in culture. These lines may prove useful in the identification and isolation of gene products that characterize individual or small subsets of DRG neurons.  相似文献   
54.
The purpose of this meta-analysis was to identify if patient-specific instrumentation (PSI) could increase the accuracy of the correction in high tibial osteotomy (HTO) and to explore the assessment indices and the necessity of using a PSI in HTO. A systematic search was carried out using online databases. A total of 466 patients were included in 11 papers that matched the inclusion criteria. To evaluate the accuracy of PSI-assisted HTO, the weight bearing line ratio (WBL%), hip-knee-ankle angle (HKA), mechanical medial proximal tibial angle (mMPTA), and posterior tibial slope angle (PTSA) were measured preoperatively and postoperatively and compared to the designed target values. Statistical analysis was performed after strict data extraction with Review Manager (version 5.4). Significant differences were detected in WBL% (MD = −36.41; 95% CI: −42.30 to −30.53; p < 0.00001), HKA (MD = −9.95; 95% CI: –11.65 to –8.25; p < 0.00001), and mMPTA (MD = –8.40; 95% CI:−10.27 to −6.53; p < 0.00001) but not in PTSA (MD = 0.34; 95% CI: −0.59 to 1.27; p = 0.47) between preoperative and postoperative measurements. There was no significant difference between the designed target values and the postoperative correction values of HKA (MD = 0.14; 95% CI: −0.19 to 0.47; p = 0.41) or mMPTA (MD = 0.11; 95% CI −0.34 to 0.55; p = 0.64). The data show that 3D-based planning of PSI for HTO is both accurate and safe. WBL%, HKA, and mMPTA were the optimal evaluation indicators of coronal plane correction. Sagittal correction is best evaluated by the PTSA. The present study reports that PSI is accurate but not necessary in typical HTO.  相似文献   
55.

Purpose

Neoadjuvant chemotherapy (NAC) can downstage invasive bladder cancers prior to radical cystectomy (RC) and improve overall survival. However, the optimal management in patients with persistent non-organ confined disease (pT3–T4 and/or pN+) following RC has not been completely defined. The aim of this study was to describe outcomes associated with the use of adjuvant chemotherapy (AC) in patients with residual non-organ confined cancer at RC following NAC.

Materials and methods

Using data from a high-volume referral institution, pT3–T4 and/or pN+ patients who received NAC and then also RC were identified. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed with Kaplan–Meier analysis.

Results

From 2001 to 2013, 161 patients received NAC and then RC. Eighty-eight pT3–T4 and/or pN+ patients were identified. Twenty-nine (33 %) received AC. Adjuvant chemotherapy in the majority of patients was carboplatin-based (16), followed by cisplatin (8) and other, mainly taxane-containing regimens (5). The median RFS was 17.5 months in the AC and 13.7 months in the non-AC group (p = 0.78). AC remained an insignificant predictor for RFS after adjusting for pT, pN and margin status (HR 0.89, 95 % CI 0.48–1.68]). CSS was 23 and 22 months (p = 0.65) and remained insignificant after adjusting for pathologic confounders.

Conclusions

In our current study population, adjuvant conventional cytotoxic chemotherapy was not associated with significant improvements in RFS or CSS. The choice of AC regimens, and incorporation of newer treatments, may be the key for improving outcomes in this high-risk patient group.
  相似文献   
56.

Background/Purpose

Complications of open conversion, hypercarbia, and intestinal injury have plagued minimally invasive approaches to congenital diaphragmatic hernia (CDH) repair in neonates. To safely begin using minimally invasive techniques for neonatal CDH repair, we formulated preoperative selection criteria and operative techniques that would enhance chances for successful thoracoscopic primary diaphragm repair and uncomplicated outcome.

Methods

During the period from January 2003 to October 2004, neonates were selected for thoracoscopic CDH repair using anatomic and physiologic criteria. Anatomically, all patients were required to have stomach in the abdomen by radiography. Physiologically, all patients were required to be on minimal ventilator support with preoperative ventilator peak inspiratory pressures in the low 20s mm Hg. No patient could have clinical evidence of pulmonary hypertension at the time of surgery. Thoracoscopic CDH repair was performed using 3 trocars (3 and 5 mm). The hernia contents were reduced into the abdomen using 5-mm Hg insufflation, and the diaphragms were repaired primarily using interrupted 3-0 Ethibond simple sutures (Ethicon, Inc, Piscataway, NJ). Posterolateral diaphragm stitches were passed around the posterolateral ribs and tied extracorporeally.

Results

Thirty neonates with CDH were admitted to Children's Hospital Boston and Vanderbilt Children's Hospital during the study period. Eight patients (27%) met selection criteria and 7 underwent thoracoscopic CDH repair. Primary diaphragmatic repair was successfully accomplished thoracoscopically in all neonates without perioperative complication. Preoperative anatomic criteria correlated accurately with intact esophageal hiatus and primary diaphragm repair. Physiologically, each patient tolerated intrathoracic insufflation and CDH repair without clinical pulmonary hypertension or blood pressure lability. Three patients had intraoperative respiratory acidosis that was reversed with ventilator changes. Operative times averaged 152 minutes and ranged from 212 to 106 minutes. Postoperative mechanical ventilation ranged from 0 to 7 days, and the length of hospitalization ranged from 5 to 32 days. Longest follow-up has been 17 months. One patient required reoperation for recurrent CDH at 10 months after repair, but there have been no other long-term complications.

Conclusions

Neonatal thoracoscopic CDH repair is safe in selected patients who have good preoperative pulmonary function and anatomy amenable to primary diaphragmatic repair. A wider range of neonates may be acceptable for thoracoscopic CDH repair with increasing surgical experience.  相似文献   
57.
Extrahepatic portal vein thrombosis (EHPVT) may occur in children or adults and usually comes to clinical attention due to complications of portal hypertension such as variceal hemorrhage. A variety of standard surgical techniques exist to manage these patients, but when these fail surgical options are limited. We describe two novel portosystemic shunts that utilize the gonadal vein as an autologous conduit. Four patients were evaluated for EHPVT with variceal bleeding. None of the patients were candidates for a standard splenorenal shunt due to prior surgical procedures. The first patient underwent a left mesogonadal shunt and the remaining 3 patients underwent a right mesogonadal shunt. Postoperative ultrasound or computed tomography (CT) scan confirmed early patency of the shunt in each patient. There have been no further episodes of variceal hemorrhage with follow-up of 3.5 years in the child who underwent the left mesogonadal shunt, and 17, 19, and 20 months in the patients who underwent the right mesogonadal shunt. Three of the 4 shunts remain patent. One shunt thrombosis occurred in a patient homozygous for the Factor V Leiden mutation despite anticoagulation with coumadin. This is the first report of the successful use of the gonadal vein as an in situ conduit for constructing a portosystemic shunt. In conclusion, the right and left mesogonadal shunts may be useful as salvage operations for patients with EHPVT who have failed standard surgical shunt procedures.  相似文献   
58.
Transmesenteric hernia is a rare cause of intestinal obstruction most commonly affecting the small bowel. The mesenteric defect is usually 2 to 3 cm in diameter. The authors describe 2 cases of young pediatric patients presenting with bowel obstruction resulting from a congenital mesenteric defect. The initial patient had a 30-cm-wide congenital defect in the ileal mesentery through which the sigmoid colon and some loops of small bowel had herniated. The second patient is a newborn infant who presented with symptoms and radiographic evidence of proximal bowel obstruction initially thought to be resulting from malrotation with midgut volvulus but was found at surgical exploration to have a small defect in the ileal mesentery.  相似文献   
59.
OBJECTIVE: To investigate the age-stratified prevalence of erectile dysfunction (ED) and its comorbidities, and to assess the population's knowledge, utilization, and general attitude towards the treatment for ED. SUBJECTS AND METHODS: In all, 10 000 men received a 35-item questionnaire including the International Index of Erectile Function (IIEF) and sociodemographic questions regarding life style, comorbidities, quality of sexual life and knowledge or experience of ED therapy. In all, 3124 responses were included (31.2%), 2499 men lived in well established partnerships and were assessed as the basic study group. RESULTS: In the entire population the prevalence rate of ED was 40.1%. However, although known, medical treatment for ED is used only by a minority of affected men. The prevalence of ED was independently associated with age, peripheral arterial occlusive disease, hypertension, ischaemic heart disease, diabetes mellitus, and liver diseases. Correlations between sexual quality of life (QoL) and ED were statistically significant (P < 0.01) and moderate to strong (absolute values: Spearman's rho 0.35-0.76). Although 96% of the study population knew at least one phosphodiesterase type 5 (PDE5) inhibitor by name, only 53% considered taking the medication and only 9% of the men with ED had had experience with available PDE5 inhibitors. CONCLUSIONS: The sexual QoL was significantly reduced by ED. Despite high levels of awareness and general acceptance of oral medication for ED, experience with PDE5 inhibitors was low. Further investigation is required to evaluate the general impact of ED on sexual QoL and the need or wish for treatment.  相似文献   
60.
Binder DK  Dillon WP  Fishman RA  Schmidt MH 《Neurosurgery》2002,51(3):830-6; discussion 836-7
OBJECTIVE AND IMPORTANCE: Spontaneous intracranial hypotension is an increasingly recognized cause of postural headache. However, appropriate management of obtundation caused by intracranial hypotension is not well defined. CLINICAL PRESENTATION: A 43-year-old man presented with postural headache followed by rapid decline in mental status. Imaging findings were consistent with the diagnosis of spontaneous intracranial hypotension, with bilateral subdural hematomas, pachymeningeal enhancement, and caudal displacement of posterior fossa structures and optic chiasm. INTERVENTION: Despite treatment with lumbar epidural blood patch, worsening stupor necessitated intubation and mechanical ventilation. Contrast-enhanced magnetic resonance imaging and computed tomographic myelography of the spine failed to demonstrate the site of cerebrospinal fluid fistula. The enlarging subdural fluid collections were drained, and a ventriculostomy was performed. Postoperatively, the patient remained semicomatose. To restore intraspinal and intracranial pressures, intrathecal infusion of saline was initiated. After several hours of lumbar saline infusion, lumbar and intracranial pressures normalized, and the patient's stupor resolved rapidly. Repeat computed tomographic myelography accomplished via C1-C2 puncture demonstrated a large ventrolateral T1-T3 leak, which was treated successfully with a thoracic epidural blood patch. Follow-up magnetic resonance imaging demonstrated resolution of intracranial hypotension, and the patient was discharged in excellent condition. CONCLUSION: Spontaneous intracranial hypotension may cause a decline of mental status and require lumbar intrathecal saline infusion to arrest or reverse impending central (transtentorial) herniation. This case demonstrates the use of simultaneous monitoring of lumbar and intracranial pressures to appropriately titrate the infusion and document resolution of intracranial hypotension. Maneuvers aimed at sealing the cerebrospinal fluid fistula then can be performed in a less emergent fashion after the patient's mental status has stabilized.  相似文献   
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