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Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS).  相似文献   
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Objective: We compare the outcome of palliative pancreaticoduodenectomy and palliative surgical bypass in patients with advanced pancreatic carcinoma in our hospital. Recent published related articles are also reviewed. Methods: A respective analysis was performed comparing the perioperative parameters and outcome of 20 patients who underwent pancreaticoduodenectomy with a gross suspected cancer residue and 30 patients who underwent a surgical bypass, all of the patients were diagnosed as in advanced stages intra-operatively. Results: The two groups were comparable with patient characteristics, including age, gender, initial symptoms and concomitant major organ diseases. Tumors are similar in size and intra-operatively diagnosed as in advanced stages in both groups. All of the patients in the resection group were microscopically proved having cancer residue. One postoperative mortality occurred in the resection group (5%), zero in the bypass group (P > 0.05). Overall complications were significantly higher in the resection group (30% vs. 0, P < 0.01), including 2 patients developed Acute Respiratory Distress Syndrome (ARDS), zero in the bypass group (P < 0.01); hemorrhage and transfusions in the resection group were much more than that in the bypass group (P < 0.05). Hospital stay after resection was significantly longer than bypass (20 vs. 12 days, P < 0.01). Hospital fee after resection was 4 times more than after bypass (median 61.500 vs. 15. 300 yuan, P < 0.01). Survival was significantly longer after resection (median 12.2 vs. 7.1 months, P < 0.01). Conclusion: Our results show that palliative resection in advanced pancreatic carcinoma lengthens the survival time of the patients, but this is paid for significantly higher complications than bypass.  相似文献   
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Purpose: To evaluate the feasibility, reliability and analgesia effect of topical anesthesia combined with subconjunctival anesthesia in anti-glaucomatous surgery.Methods: Two hundred and four cases (357 eyes) underwent anti-glaucomatous surgeries under topical anesthesia with 0.5% Alcaine eye drops combined with subconjunctival anesthesia with 2% Lidocaine. The analgesic effect was analysed with visual analogue pain scale.Results: Among all of 357 eyes, 62 eyes underwent peripheral iridectomy, 67 eyes underwent simple trabeculectomy, 167 eyes underwent compound brabeculectomy and 12 eyes nonpenetrating trabecular surgery. The effects of anesthesia were as follows: 304 eyes (85.2%) were painless (Grade Ⅰ), 50 eyes (14.0%) were slight painful (Grade Ⅱ), and 3 eyes (0.8%) were more painful (Grade Ⅲ) during surgery. And no severe complications were observed in all the cases during surgery and postoperatively. Amaurosis fugax was not observed in the glaucoma patients at the late stage with narrow vi  相似文献   
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A combination of levonorgestrel 0.15mg and ethinyl estradiol 0.03mg, an ultra-low dose oral con traceptive in pellet form, was tried out in 9 Beijing clinics. A total of l,035 healthy women of reproduc tive age participated in 9,413 cycles of treatment. Only one pregnancy was attributed to medication failure which resulted in a corrected Pearl index of 0.13/100 women-year. The incidence of breakthrough bleeding and amenorrhea was 0.12% and 0.05% res pectively. Using the life-table method, the net cumulative rate of termination due to medical-related reasons at one year was only 5.93/100 women. The incidence of side effects was low. The most frequent complaints were nausea and drowsiness, which re duced with the increase of treatment cycles. Some metabolic changes were studied. In comparison with other OCs used in China, this formula has the advantages of ultra-low-dose steroids with higher contraceptive efficacy, better cycle control and fewer side effects.  相似文献   
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采用差示分光光度法测定伤风止咳露中盐酸异丙嗪的含量。以H2O2冰醋酸为氧化剂将盐酸异丙嗪氧化,测定氧化前后的吸收度差值。其△A值与盐酸异丙嗪在一定浓度范围内呈线性关系。该法操作简便、快速、结果准确。  相似文献   
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Eighteen trabeculectomy specimens of congenital glaucoma were examined by light and transimssion electron microscopy. The results showed that the primary anomalies in congenital glaucoma included the developmental defects of trabecular meshwork, excessive collagen fibrils in the trabecular matrix, shifting forward of ciliary muscle fibres and persistent mesenchymal tissues in the anterior-chamber angle. The authors also pointed out the importance of the secondary lesions of the trabecular meshwork in the pathogenesis of congenital glaucoma. Eye Science 1994; 10:50-56.  相似文献   
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Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs were abnortmal. Six eyes had the visual acuity from 0. 2 to 0. 4, in which the EOGs of 5 eyes were abnormal. Six eyes had the visual acuity more than 0. 5, a-mong which the EOGs of 4 eyes were abnormal. Based on the above observations, it may be considered that the circulatory disturbance resulting from RVO damages not only the internal layer but also the external layer of the retina. We suggest that EOG is a useful method for distingquishing lesions caused by RVO and may reflect the functional condition  相似文献   
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By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162.  相似文献   
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