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1.
In spite of electrodiagnostic examinations, the determination of the precise localization of the injured site along the involved peripheral nerve may remain obscure or uncertain. Before starting the operation, a surgeon should have knowledge about the type of injury, the position of the proximal and distal nerve stumps, and the presence or absence of a neuroma and excessive perilesional scar tissue formation for orientation and planning of the surgical intervention. We hypothesized that real-time ultrasound could be helpful in the determination of the type of injury, the localisation of proximal and distal nerve stumps, as well as for diagnosing a neuroma. Fourteen patients with traumatic peripheral nerve injuries that were verified by neurological examinations and electrodiagnostic tests underwent surgical repair, and were examined by ultrasound before and during the surgical intervention. Visualisation of the injured site, the type of the injury, the position of the nerve stumps and the diagnosis of the neuroma were reliably feasible in all the patients by using ultrasonography. Axonal swelling of a nerve was diagnosed in 4 (29 %) patients, a stump neuroma was diagnosed in 3 (21 %) patients, a total nerve interruption (neurotmesis in the Seddon classification) was diagnosed in 9 (64 %) patients, and surrounding scar tissue was diagnosed in 5 (35 %) patients. Presurgical and intraoperative ultrasound-assisted neuroexamination is a useful diagnostic method in the determination of the precise localisation of the injured site, the type of injury, the position of stumps, and the diagnosis of a neuroma. The use of preoperative and intraoperative ultrasound can enhance the orientation of the surgeon to the surgical field. The application of our method to our patients shows that presurgical ultrasonographic neuroexamination can be used in the surgical repair of peripheral nerve injury.  相似文献   
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BACKGROUND: Most of our knowledge concerning obstructive uropathy has been derived mainly from surgically manipulated animal models, and the pathogenesis of congenital obstructive hydronephrosis is not fully elucidated. Nitric oxide (NO) acts as an important biological modulator with diverse physiological functions, which can be either toxic or protective depending on the situation. NO is synthesized from l-arginine by nitric oxide synthase, and in the kidney iNOS is expressed spontaneously. The aim of our study is to investigate the expression of iNOS protein and its relationship with tubulointerstitial fibrosis and tubular cell apoptosis in congenital hydronephrosis. METHODS: We conducted histological studies on 18 kidneys of six-week-old-rats from an inbred colony of congenital hydronephrosis with reference to the histological grading of the affected kidney, tubulointerstitial fibrosis, renal tubular atrophy, and tubular cell apoptosis. Renal transforming growth factor-beta1 (TGF-beta1) level was determined by a sandwich ELISA assay and the expression of iNOS was analyzed by western blotting. RESULTS: Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. Renal TGF-beta1 level was higher in hydronephrotic kidneys than normal control kidneys (364.81 +/- 52.60 vs. 221.19 +/- 22.53 pg/mg protein, P < 0.05). Tubular apoptotic score in hydronephrotic kidneys was also significantly higher than in the normal control kidneys (1.97 +/- 0.42 vs. 0.14 +/- 0.02/HPF, P < 0.01). The expression of iNOS protein was lower in the affected kidneys compared with the normal control kidneys (8.79 +/- 0.78 vs. 14.00 +/- 0.83 arbitrary unit, P < 0.01). There was a negative correlation between iNOS expression and histological grading in congenital hydronephrosis. The iNOS expression also correlated negatively with renal interstitial fibrosis, TGF-beta1 level and tubular cell apoptosis. CONCLUSION: Our study confirmed the down-regulation of iNOS expression in affected kidneys from rats with congenital hydronephrosis, in which the cytoprotective effect of NO may be lost or weakened.  相似文献   
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The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury.  相似文献   
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Enhancing effect of chitosan on peptide drug delivery across buccal mucosa   总被引:11,自引:0,他引:11  
Senel S  Kremer MJ  Kaş S  Wertz PW  Hincal AA  Squier CA 《Biomaterials》2000,21(20):2067-2071
The buccal mucosa represents a potentially important topical route for delivery of peptide or protein drugs with some unique advantages such as the avoidance of hepatic first-pass metabolism and the acidity and protease activity encountered in the gastrointestinal tract. However, the bioavailabilities or relative potencies of intraorally administered peptides are usually quite low, unless permeabilizers are employed. Chitosan, a mucopolysaccharide of marine origin, has been claimed to act both as a bioadhesive and permeabilizer, making it a candidate system for mucosal drug delivery. In this study, the enhancement effect of chitosan in gel form for oral mucosa was investigated with a large bioactive peptide, transforming growth factor-beta (TGF-beta). Chitosan gel was prepared at 2% concentration in dilute lactic acid and TGF-beta was incorporated into the gel. The effect of chitosan as a permeabilizer was determined by measuring the flux of TGF-beta across porcine oral mucosa in an in vitro system. The localization of TGF-beta within the oral mucosa was determined by horizontal sectioning and counting. Chitosan was found to exert a marked permeabilizing effect on buccal mucosa for peptide drug.  相似文献   
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反相高效液相色谱测定丹参注射剂的三种有效成分   总被引:22,自引:0,他引:22  
倪坤仪  张国清 《药学学报》1988,23(4):293-297
本文用反相高效液相色谱法,采用离子抑制技术分离了丹参注射剂中三种有效成分:丹参素、原儿茶醛、原儿茶酸。并用外标法测定了它们在丹参注射液和复方丹参注射液中的含量。考察了Waters公司分析柱(3.9×300 mm)和径向加压柱(8×100 mm),以及国产色谱柱(5×150mm)分析样品,均能获得满意的结果。比较了用多通道紫外吸收检测器和254nm固定波长紫外检测器测定样品时灵敏度的差异。  相似文献   
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The aim of this study was to evaluate the bone mineral density (BMD) in familial Mediterranean fever (FMF) and to search the effects of genetic factors, family history of FMF and types of clinical attacks on BMD. Forty-four attack-free patients with FMF and 36 healthy voluntary subjects were included in the study. BMD measurements of lumbar spine and left proximal femur were performed by dual energy X-ray absorptiometry (DEXA). There was no statistically significant difference between patient and control groups regarding median values of lumbar BMD (P?=?0.06), lumbar T (P?=?0.08) and Z (P?=?0.12) scores, femoral neck BMD (P?=?0.13), femoral T (P?=?0.22) and Z (P?=?0.16) scores and total femur BMD (P?=?0.14), T (P?=?0.19) and Z (P?=?0.27) scores. Patients with negative FMF family history had significantly lower femoral neck BMD (P?=?0.018), femoral neck T (P?=?0.009) and Z (P?=?0.01) scores and total femur BMD (P?=?0.033) than patients with positive FMF family history. There was no significant difference among the groups regarding mutation characteristic and types of attacks in lumbar BMD, T and Z scores, femoral neck BMD, T and Z scores and total femur BMD, T and Z scores (P?>?0.05). We found that the bone loss of patients with FMF is not different from that of the controls. The increased bone loss in the patients with negative family history for FMF should be further investigated with larger patient groups taking into consideration of the risk factors related to family history for osteoporosis.  相似文献   
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