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991.
992.
目的探讨基因重组碱性成纤维细胞生长因子(bFGF)对急性坏死性胰腺炎(ANP)犬肠道细菌移位的影响。方法杂种犬23只,分对照组(n=7)、ANP组(n=8)和bFGF组(n=8)。bFGF组犬复制ANP模型后,每日静脉注射bFGF(5μg/kg)。结果bFGF治疗后,ANP犬肠粘膜损伤明显减轻,脏器细菌培养阳性率下降50%,细菌移位数量减少93.3%-96.7%,肠粘膜蛋白质、DNA含量显著增加(P<0.05),丙二醛含量明显减少(P<0.05)。结论bFGF可显著减少ANP时肠道细菌移位,其机制可能是通过增加肠粘膜蛋白质合成,促进肠粘膜损伤修复。  相似文献   
993.
During a 2-year period, 34 patients of catatonic features in Chinese ethnic background Taiwanese were brought to the emergency unit of Chang Gung Memorial Hospital at Linkou. The ratios of the causes of catatonic features by schizophrenic disorders, mood disorders, neuroleptic-induced disorders, and general medical conditions were 26, 9, 24 and 41%, respectively. After the treatments of antipsychotics, benzodiazepam, or electroconvulsive therapy (ECT), 24 patients (70.6%) showed complete remission, seven patients (20.6%) showed partial remission, and three patients (8.8%) showed no response (two died). Additionally, a suggestive period is proposed in order to distinguish acute and insidious onset catatonic conditions to help clinicians in deciding on probability immediately. The patients were grouped into four diagnostic categories; namely, schizophrenic disorders, mood disorders, neuroleptic-induced disorders, and general medical conditions for comparison. One-way ANOVA and Duncan's multiple-range test were used for continuous variables, and the Chi-squared test was used for categorical variables. The mean duration of 'insidious onset catatonic condition' (including schizophrenic disorders and general medical conditions) before seeking medical help was longer than 3.33 weeks, while the mean duration of 'acute catatonic condition' (including mood disorders and neuroleptic-induced disorders) was shorter than 1.83 weeks. These findings suggest that 2-3 weeks would be a cut-off point for acute or insidious onsets of catatonic conditions.  相似文献   
994.
Intestinal cytokine response after gut ischemia: role of gut barrier failure   总被引:15,自引:0,他引:15  
OBJECTIVE: To investigate the effect of intestinal ischemia with and without a reperfusion injury on intestinal cytokine production and gut permeability. SUMMARY BACKGROUND DATA: In humans and in animal models, the gut has been implicated as a cytokine-producing organ after ischemia/reperfusion (I/R)-type injuries. Because of the limitations of in vivo models, it has been difficult to demonstrate directly that the gut releases cytokines after an I/R injury or whether there is a relation between the magnitude of the ischemic process and the cytokine response. METHODS: Ileal mucosal membranes from rats subjected to sham or 45 or 75 min of superior mesenteric occlusion (SMAO) or 45 minutes of SMAO and 30 minutes of reperfusion (SMAO 45/30) were mounted in the Ussing chamber system. Levels of tumor necrosis factor-alpha and interleukin-6 were serially measured in the mucosal and serosal reservoirs of the Ussing system, as was mucosal permeability as reflected by the passage of bacteria or phenol red across the ileal membrane. In a second group of experiments, Escherichia coli C25 was added to the mucosal reservoir to determine if the cytokine response would be increased. RESULTS: Mucosal and serosal levels of tumor necrosis factor-alpha were equally increased after SMAO, with the highest levels in the 75-minute SMAO group. The highest levels of interleukin-6 were found in rats subjected to 75 minutes of SMAO or SMAO 45/30; the serosal levels of interleukin-6 were four to sixfold higher than the mucosal levels. The addition of E. coli C25 resulted in a significant increase in the amount of interleukin-6 or tumor necrosis factor-alpha recovered from the mucosal reservoir. Increased ileal membrane permeability was observed only in rats subjected to 75 minutes of SMAO or SMAO 45/30. CONCLUSION: These results directly document that the levels of tumor necrosis factor-alpha and interleukin-6 released from the gut increase after an ischemic or I/R injury, such as SMAO, and that there is a relation between the magnitude of the gut ischemic or I/R insult and the cytokine response.  相似文献   
995.
Balloon angioplasty is a standard treatment for artherosclerotic coronary artery disease. However, its clinical value is reduced by a high restenosis rate. A new concept in preventing restenosis is the use of a liquid-filled balloon containing a beta-emitting radioisotope. In this study, we performed biodistribution studies of Re-188 perrhenate and Re-188 diethylenetriaminopentaacetate (DTPA) to assess the resulting organ dose values in the event of balloon rupture if these agents are used for the clinical inhibition of restenosis after percutaneous transluminal coronary angioplasty (PTCA). After injecting Re-188 preparations intravenously, rats were killed at 10 min, 30 min, 60 min, 2 h, and 6 h ( n =5 per group). Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (%ID/g or %ID/mL). In addition, urine excretion and thyroid gland uptake were evaluated in rats ( n=5 per group) with a gamma camera after administration of 37 MBq (1 mCi) of each agent. Our data showed that both agents were excreted primarily via urine. However, the excretion of Re-188 DTPA was much faster than that of Re-188 perrhenate via the urinary system. The biodistribution data revealed that radioactivity levels in the stomach and the thyroid gland were high in the perrhenate group but low in the Re-188 DTPA group. The concentration levels in other tissues including lung, liver, testis, muscle, and blood were low throughout this study for both agents. The thyroid radiation value in the Re-188 perrhenate group was 0.163 mGy/MBq, which was much higher than that of the Re-188 DTPA group (0.0167 mGy/MBq). The stomach radiation value was as high as 0.127 mGy/MBq for Re-188 perrhenate, compared with 0.013 mGy/MBq for Re-188 DTPA. In conclusion, in the event of balloon rupture, the release of Re-188 DTPA results in lower radiation doses than Re-188 perrhenate, especially to the thyroid gland and the stomach. Our data suggest that Re-188 DTPA is a useful radiopharmaceutical for endovascular irradiation.  相似文献   
996.
OBJECT: The purpose of this study was to analyze the change in carotid and middle cerebral artery (MCA) hemodynamics before and after endoscopic upper thoracic sympathectomy in patients with palmar hyperhidrosis (PH). METHODS: Sixty-eight patients with PH (35 males and 33 females) for whom the average age was 24.5+/-10.7 years (+/- standard deviation) were recruited into this study. These patients all underwent routine upper T-2 sympathectomy to treat their PH. Ultrasonography studies of the carotid arteries (CAs) and MCA were obtained in each patient before and after T-2 sympathectomy. The blood flow volume, flow velocity, and resistivity index (RI) in the bilateral common CAs (CCAs), internal CAs (ICAs), and external CAs (ECAs) were evaluated using duplex ultrasonography. The systolic peak velocity, mean velocity, diastolic peak velocity, pulsatility index, and RI of the bilateral MCAs were evaluated using transcranial Doppler ultrasonography. Blood pressure and heart rate were also recorded during this study. The Student paired t-test was used to analyze the differences between studies before and after bilateral T-2 sympathectomy. There was a significant reduction in diastolic pressure after T-2 sympathectomy (p = 0.003), but not in systolic pressure or heart rate. The vessel diameter was increased after sympathectomy in the left CAs and right CCA. The T-2 sympathectomy led to significant elevation of blood flow volume and RI in the left CCA, ICA, and ECA (p < 0.05). The authors found significant increases in maximum flow velocity and RI in the left MCA (p < 0.05). CONCLUSIONS: Patients who underwent T-2 sympathectomy demonstrated a significant increase in blood flow volume and flow velocities of the CAs and MCA, especially on the left side. Asymmetry of sympathetic influence on the hemodynamics of the CAs and MCA was noted. The usefulness of sympathectomy for the treatment of ischemic cardiovascular and cerebrovascular disease deserves further investigation.  相似文献   
997.
Osteoclasts are exposed to unusually high, millimolar, Ca2+ concentrations and can "sense" changes in their ambient Ca2+ concentration during resorption. This results in a sharp cystolic Ca2+ increase through both Ca2+ release and Ca2+ influx. The rise in cystolic Ca2+ is transduced finally into an inhibition of bone resorption. We have shown that a type 2 ryanodine receptor isoform, expressed uniquely in the osteoblast plasma membrane, functions as a Ca2+ influx channel, and possibly as a Ca2+ sensor. Ryanodine receptors are ordinarily microsomal membrane Ca2+ release channels. They have only recently been shown to be expressed a other sites, including nuclear membranes. At the latter site, ryanodine receptors gate nucleoplasmic Ca2+ influx. Nucleoplasmic Ca2+, in turn, regulates key nuclear processes, including gene expression and apoptosis. Here, we review potential mechanisms underlying the recognition, movement, and actions of Ca2+ in the osteoclast.  相似文献   
998.
脑出血并发肺部感染对神经功能恢复的影响   总被引:3,自引:1,他引:2  
对1995-1997年收治的64例脑出血病人进行回顾性分析,31例并发肺部感染,33例无肺部感染。两组病人入院,出院时,按卒中病人临床神经功能缺损程度评分标准(NDS)评定其神经功能恢复的差值。肺部感染组NDS差值为0.3±6.1,无肺部感染组DNS差值为6.1±2.9,两组DNS差值经秩和检验有显著性差异(P〈0.01),提示脑出血病人并发肺部感染可影响其神经功能恢复;预防和控制肺部感染可促进神  相似文献   
999.
Background: Sentinel lymph node (SLN) biopsy can accurately predict the presence of metastatic melanoma (MM) and has been used to identify patients with occult metastases. We present an analysis of the sensitivity and specificity of standard pathological techniques including intraoperative frozen section, permanent section, and immunohistochemistry in diagnosing MM within the SLN.Methods: Sixty-nine consecutive patients with primary malignant melanoma thickness of .1.0 mm or thinner lesions invading the reticular dermis (Clark level IV) who underwent SLN biopsy were reviewed. Lymph nodes were examined intraoperatively by frozen section (FS), permanent section (H&E), and by immunohistochemistry (IH) for S-100 protein and HMB45.Results: MM was found in 14 of 69 cases (20%). Permanent section H&E was performed in all cases, FS in 64 cases, and IH in 65 cases. FS analysis diagnosed MM in 4 of 14 cases (29%), was suspicious in 2 of 14 (14%), and falsely negative (FN) in 8 of 14 (57%) ultimately found to be positive with further workup. Within the FN group, MM was identified on review of the original FS slides in 3 of 8 cases (38%). Furthermore, within the FN group, the remaining 5 cases were identified as positive for MM by either permanent and/or deeper H&E sections and IH. IH alone with permanent H&E sections would have diagnosed MM in only 8 of 10 cases (80%) that were FS negative or suspicious. In no cases was MM identified by IH alone with the permanent and deeper H&E sections being negative. It is noteworthy that no false-positive cases were identified.Conclusions: Intraoperative FS has low sensitivity in identifying MM within the SLN. IH alone does not increase the diagnostic yield. A combination of permanent H&E sections with deeper levels and S-100 and HMB45 IH dramatically increases the overall diagnostic sensitivity of SLN biopsy. Definitive diagnosis should await permanent H&E sections and IH staining.  相似文献   
1000.
Primary subtalar arthritis is not common. In most cases, it is the late sequela of intra-articular calcaneal fracture. Subtalar arthrodesis is mostly used for the treatment of traumatic subtalar arthritis in our clinics. We have compared our early cases of in-situ subtalar fusion with our recent cases of fusion with sliding corrective osteotomy in this clinical report. From 1989 to 1992, 15 feet of 13 patients were treated with subtalar arthrodeses for subtalar arthritis caused by malunion of calcaneal fractures. Fusion in situ was done by Ollier's approach, and resection of bony protrusion was done if there was lateral entrapment syndrome. From 1992 to 1995, 13 feet of 12 patients also received subtalar arthrodeses to salvage their calcaneal fractures, but the subtalar fusion was done by wide lateral approach, calcaneal sliding corrective osteotomy, and sometimes (11 of 13 feet) with Achilles tendon lengthening to restore the calcaneal height and width. Patients of both groups experienced obvious clinical improvement in subtalar pain relief, but there was no difference with walking distance, running, or jumping. The group undergoing fusion with sliding corrective osteotomy was more satisfied with regard to cosmetic results and shoe wear. The overall satisfactory rate in the group who underwent fusion with sliding corrective osteotomy (92%) was superior to the group who underwent fusion in situ (77%). Though our method of sliding corrective osteotomy does not provide much improvement to the talus declination angle, it is suitable for those patients with a "banana"-shaped calcaneus malunion. If the patient has prominent anterior ankle pain caused by tibiotalar impingement, we believe that a distraction subtalar arthrodesis would be more appropriate.  相似文献   
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