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71.
PURPOSE: Pathological neovascularisation within the normally avascular cornea is a serious event that can interfere with normal vision. Upregulation of vascular endothelial growth factor (VEGF) has been associated with neovascularisation in the eye, suggesting that maintaining low levels of VEGF is important for corneal avascularity and intact vision. This study aims to determine the expression profile and possible contribution of sVEGFR-1 to the corneal avascular barrier. DESIGN: Experimental case series investigating VEGF and soluble fms-like tyrosine kinase (sFlt) levels in normal and neovascularised human corneas. PARTICIPANTS: Four normal human corneas, five human corneas with alkali burns, three human corneas with aniridia, one with ocular cicatricial pemphigoid and two with interstitial keratitis were examined. METHODS: Western blot and immunohistochemical analyses were performed to determine sFlt and VEGF levels in normal and neovascularised human corneas. Immunoprecipitation was utilised to demonstrate sFlt-VEGF binding. RESULTS: Normal human corneas strongly express sFlt in the corneal epithelium and weakly in the corneal stroma close to the limbus. VEGF is bound by sFlt in the normal human cornea. Neovascularised human corneas have greatly reduced expression of sFlt and significantly less VEGF bound by sFlt. CONCLUSIONS: sFlt is highly expressed in the human cornea and normally sequesters VEGF.  相似文献   
72.
Approximately 10%-20% of the cases of acute pancreatitis have acute necrotizing pancreatitis. The infection of pancreatic necrosis is typically associated with a prolonged course and poor prognosis. The multidisciplinary, minimally invasive “step-up” approach is the cornerstone of the management of infected pancreatic necrosis (IPN). Endosonography-guided transmural drainage and debridement is the preferred and minimally invasive technique for those with IPN. However, it is technically not feasible in patients with early pancreatic/peripancreatic fluid collections (PFC) (< 2-4 wk) where the wall has not formed; in PFC in paracolic gutters/pelvis; or in walled off pancreatic necrosis (WOPN) distant from the stomach/duodenum. Percutaneous drainage of these infected PFC or WOPN provides rapid infection control and patient stabilization. In a subset of patients where sepsis persists and necrosectomy is needed, the sinus drain tract between WOPN and skin-established after percutaneous drainage or surgical necrosectomy drain, can be used for percutaneous direct endoscopic necrosectomy (PDEN). There have been technical advances in PDEN over the last two decades. An esophageal fully covered self-expandable metal stent, like the lumen-apposing metal stent used in transmural direct endoscopic necrosectomy, keeps the drainage tract patent and allows easy and multiple passes of the flexible endoscope while performing PDEN. There are several advantages to the PDEN procedure. In expert hands, PDEN appears to be an effective, safe, and minimally invasive adjunct to the management of IPN and may particularly be considered when a conventional drain is in situ by virtue of previous percutaneous or surgical intervention. In this current review, we summarize the indications, techniques, advantages, and disadvantages of PDEN. In addition, we describe two cases of PDEN in distinct clinical situations, followed by a review of the most recent literature.  相似文献   
73.
We report a patient who presented with coronary cameral fistula from left main coronary artery (LCA), which had spontaneously closed by the presence of clots and debris at the distal end of the fistula, with associated severe aortic regurgitation and vegetations in aortic valve. The patient was successfully treated by evacuation of clots and debris, closure of the fistula and aortic valve replacement.  相似文献   
74.
Dermatofibrosarcoma protuberans is a low grade soft tissue tumour of skin and frequently recurs. It is a locally invasive tumour and hence wide excision is required to minimize recurrences. Tumours of low mitotic rate, less than 5 per 10 high power fields with a lesser degree of cellularity and anaplasia tend to follow a more indolent course than those with moderate to high grades with higher mitotic rates.  相似文献   
75.
Gastric pull-up with cervical oesophagogastric anastomosis is a common procedure after oesophageal resection. Contrast studies are used by many surgeons for detection of anastomotic leaks but may be unnecessary. A prospective study was undertaken to compare gastrografin study and test feeding using water for detection of cervical anastomotic leaks. In 25 patients. gastrografin study showed three leaks, two of which were clinically silent and patients did not have any problems. One patient had aspiration of contrast and the study could not be completed. Two of the leaks detected clinically were missed by contrast study (one because of an incomplete study and the other was a satisfactory study). Delayed leaks occurred in two patients. All leaks healed spontaneously. A contrast study may thus be unnecessary for evaluation of a cervical oesophagogastric anastomosis and can be replaced with the simpler and safer technique of ‘test feeding’ using water.  相似文献   
76.
BACKGROUND CONTEXT: Although autogenous bone is still considered to be the gold standard graft material for promoting spinal fusion, other bone graft substitutes have been developed in an attempt to improve arthrodesis rates and avoid the complications associated with the procurement of autograft. The bone morphogenetic proteins (BMPs) represent a family of osteoinductive growth factors that are known to stimulate the osteoblastic differentiation of stem cells. Osteogenic protein-1 (OP-1) Putty is a commercially available BMP preparation that is already approved for use in humans. Previous clinical studies involving patients with degenerative spondylolisthesis have reported that the efficacy and safety of OP-1 Putty is comparable to that of autograft at both 1- and 2-year follow-up. PURPOSE: The purpose of this study was to evaluate the intermediate-term efficacy and safety of OP-1 Putty as an alternative to autogenous bone by comparing the 4-year radiographic, clinical, and safety data of these same patients who underwent decompression and uninstrumented fusion with either OP-1 Putty or iliac crest autograft. STUDY DESIGN/SETTING: A prospective, randomized, controlled, multicenter clinical pilot study. PATIENT SAMPLE: Thirty-six patients undergoing decompressive laminectomy and single-level uninstrumented fusion for degenerative spondylolisthesis and symptomatic spinal stenosis were randomized in a 2:1 fashion to receive either OP-1 Putty (24 patients) or autogenous iliac crest bone graft (12 patients). OUTCOME MEASURES: Patient-reported outcome measures consisting of Oswestry Disability Index and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) scores were used to evaluate clinical efficacy. Perioperative data including operative time, estimated blood loss, and duration of hospital stay were also recorded for each surgery. Postoperatively, a neurological examination and an assessment of donor-site pain (if applicable) were performed at every follow-up visit. Radiographic fusion success was defined as the presence of continuous bridging bone formation between the transverse processes at the level of the spondylolisthesis with minimal motion evident on dynamic lateral x-ray films. The primary efficacy endpoint was the overall success rate, a composite measure derived from both radiographic and clinical parameters. The safety of OP-1 Putty was confirmed by comparing the nature and frequency of all adverse events and complications that were prospectively observed in either of the groups. METHODS: Thirty-six patients with degenerative spondylolisthesis and symptoms of neurogenic claudication underwent decompressive laminectomy and single-level uninstrumented fusion with either OP-1 Putty or autograft. All patients were evaluated at 6 weeks and 3, 6, 9, 12, and 24 months, after which time they were instructed to return on a yearly basis. Multiple neuroradiologists blinded to the assigned treatment reviewed static and dynamic X-ray films with digital calipers to assess fusion status according to the presence of continuous bridging bone across the transverse processes as well as the amount of residual motion evident at the level of interest. Oswestry Disability Index surveys and SF-36 questionnaires were used to assess clinical outcomes. RESULTS: At the 48-month time point, complete radiographic and clinical data were available for 22 of 36 patients (16 OP-1 Putty and 6 autograft) and 25 of 36 patients (18 OP-1 Putty and 7 autograft), respectively. Radiographic evidence of a solid arthrodesis was present in 11 of 16 OP-1 Putty patients (68.8%) and 3 of 6 autograft patients (50%). Clinically successful outcomes defined as at least a 20% improvement in preoperative Oswestry scores were experienced by 14 of 19 OP-1 Putty patients (73.7%) and 4 of 7 autograft patients (57.1%); these clinical findings were corroborated by similar increases in SF-36 scores. The respective overall success rates of the OP-1 Putty and autograft group were 62.5% and 33.3%. In this study, there were no incidents of local or systemic toxicity, ectopic bone production, or other adverse events directly related to the use of OP-1 Putty. CONCLUSION: Despite the challenges associated with obtaining a solid uninstrumented fusion in patients with degenerative spondylolisthesis, the rates of radiographic fusion, clinical improvement, and overall success associated with the use of OP-1 Putty were at least comparable to that of the autograft controls for at least 48 months after surgery. These results appear to validate the short-term results previously reported for OP-1 Putty and suggest that this material may potentially represent a viable bone graft substitute for certain fusion applications.  相似文献   
77.
It has been proposed previously that the metabolic defect in pseudohypoparathyroidism which accounts for parathyroid hormone unresponsiveness is an absence or abnormal form of the adenyl cyclase system in kidney and presumably in bone. To determine whether there is an associated defect in the response mechanism to cyclic adenosine 3',5'-monophosphate (cyclic AMP), the effects of parathyroid extract (PTE), and dibutyryl cyclic AMP were compared in patients with either surgical hypoparathyroidism or pseudohypoparathyroidism. PTE and dibutyryl cyclic AMP both increased serum and urinary calcium, lowered the serum phosphorus, and increased urinary phosphorus in patients with hypoparathyroidism. PTE also increased urinary cyclic AMP in these patients. PTE increased serum and urinary calcium and urinary phosphorus but did not alter serum phosphorus or urinary cyclic AMP in the patients with pseudohypoparathyroidism. Dibutyryl cyclic AMP increased the serum and urinary calcium, lowered the serum phosphorus, and increased urinary phosphorus in all the patients with pseudohypoparathyroidism. The results indicate that (a) dibutyryl cyclic AMP can reproduce the effects of parathyroid hormone on calcium and phosphorus metabolism in man, (b) the response mechanism to cyclic AMP appears to be intact in pseudohypoparathyroidism, and (c) PTE apparently produces some of its characteristic effects on calcium and phosphorus metabolism in pseudohypoparathyroidism in the absence of an increase in urinary cyclic AMP.  相似文献   
78.
PURPOSE: To examine the clinical consequences and/or potential need for postinterventional transposition after stent-graft occlusion of the left subclavian artery (LSA). METHODS: The records of 171 consecutive patients (128 men; mean age 60.2+/-13.2 years, range 20-83) undergoing elective stent-graft repair in the thoracic aorta were reviewed to identify intentional endograft coverage of the ostial LSA, as documented by transesophageal echocardiography and/or aortography. Patients were treated for subacute type B dissection, true aneurysm, pseudoaneurysm, or previously operated type A dissection with persistent false lumen flow in the descending aorta. Among the 171 cases, 22 (12.9%) patients were identified with stent-graft occlusion of the LSA. RESULTS: A systolic blood pressure differential existed between the right (138.4+/-14.0 mmHg) and the left (101.8+/-21.0 mmHg; p<0.05) arms after occlusion of the LSA. No patient showed a malperfusion syndrome during postinterventional hospitalization. During a mean follow-up of 24.0+/-15.8 months, 15 (68.2%) patients remained completely asymptomatic, with no functional deficit or temperature differential between the arms, while 7 patients reported mild symptoms of a subclavian steal syndrome. However, no patient required any secondary surgical intervention. CONCLUSIONS: Stent-graft-induced occlusion of the ostial LSA was tolerated by all patients without chronic functional deficit. In the absence of stenotic vertebral and/or carotid arteries and with a documented intact vertebrobasilar system, prophylactic transposition of the LSA is not required prior to intentional stent-graft occlusion of the LSA.  相似文献   
79.

Introduction

Access osteotomies provide direct exposure to inaccessible areas of the deep part of craniofacial skeleton for treating pathologies involving vital structures. The use of maxillary swing approach for gaining wide access to the nasopharynx, infratemporal fossa, parapharyngeal space, middle fossa of skull base. Though the maxillary swing requires transfacial incision for wide exposure but with careful handling the scar is minimum and this approach can be used in young people.

Materials and Methods

Surgical resection is carried out following preoperative embolization of the involved feeder vessels. Total 16 cases were considered for this study.

Results

This article highlights cases successfully treated in our institution, the mention of complications associated with the cases along with management.

Conclusion

Maxillary swing is a good approach for getting access to the deep pathologies like JNA.
  相似文献   
80.
The objective of the present investigation was to optimize extraction conditions for maximum recovery of bioactive phenolics from different parts of Saraca asoca. Extraction recovery was optimized using a mixture of methanol and water in different proportions. For identification and quantification of six analytes, a rapid reversed phase ultra-performance liquid chromatography (UPLC) photo diode array detection method was developed. UPLC separation was achieved in a gradient elution mode on a C18 column with acetonitrile and aqueous phosphoric acid (0.1%, pH = 2.5). Extraction solvent for maximum recovery of analytes varied depending on the nature of matrices. The developed UPLC method was validated in accordance with International Council for Harmonisation (ICH) guidelines. Wide linearity range, sensitivity, accuracy, short retention time, and simple mobile phase composition implied that the method could be suitable for routine analysis of all six analytes with high precision and accuracy. The uniqueness of this study is the determination of the distribution of these compounds in the various parts of S. asoca.  相似文献   
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