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101.
目的了解初级护士资格考试通过情况。方法采用历史性研究方法,对我校近3年参加护士资格考试的188名学生考试情况进行调查。结果护士资格考试通过率低,其中基础知识通过率在4个科目中最低。结论有必要对参加考试的考生进一步强化基础知识的训练,从而提高护士资格考试的过线率。 相似文献
102.
103.
胸腰椎骨折术后内固定松动、断裂的原因及预防 总被引:14,自引:3,他引:11
目的 探讨椎弓根螺钉系统用于胸腰椎骨折术后出现松动、断裂的原因,并提出相应的预防对策。方法 12例胸腰椎骨折术后内固定失效病例,采用RF系统3例,AF系统9例。均未行植骨融合,AF系统中未按要求安装横连结3例,术后伤椎前缘高度平均恢复至正常的85.2%。结果 术后8—21个月出现棒断裂4例,螺钉断裂3例,钉帽松动5例。结论 内固定物的自身问题、术者的经验欠缺及操作不规范是胸腰椎骨折术后椎弓根螺钉系统松动、断裂的原因,但伤椎骨结构未能得到良好重建及术后椎间盘退变可能是其更重要的因素。因此重视内固定物的选择、加强规范操作,强调对损伤椎体及椎间盘的全面处理是预防内固定失效的有效措施。 相似文献
104.
The effect of p.o. administration of tea on nitrosamine-induced carcinogenesis was investigated. Female A/J mice were given N-nitrosodiethylamine (NDEA) (10 mg/kg) p.o. once a week for 8 weeks and were killed 16 weeks after the last dose. More than 90% of the mice had forestomach and lung tumors. The animals had an average of 8.3 forestomach and 2.5 lung tumors/mouse. With 0.63 or 1.25% green tea infusion (12.5 g green tea leaves brewed with 1 liter of boiling water) as the sole source of drinking water for the entire experimental period, the pulmonary tumor incidence was decreased by 18 or 44%, and the tumor multiplicity was reduced by 36 or 60%, respectively. The treatments also decreased the forestomach tumor incidence by 18 or 26% and tumor multiplicity by 59 or 63%, respectively. Administration of 0.63 or 1.25% green tea infusion, either during the NDEA treatment period only or starting 1 week after the completion of NDEA treatment, also decreased the pulmonary tumor incidence and multiplicity and the forestomach tumor multiplicity. The inhibitory effects of green tea infusion were also observed in a similar experiment using a higher dosage of NDEA (20 mg/kg). Treatment of female A/J mice with a single dose (103 mg/kg) of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) resulted in the formation of pulmonary adenomas in almost all of the animals with an average of 9.3 tumors/mouse after 16 weeks. When 0.6% decaffeinated green tea or black tea extract was given during the NNK-treatment period, tumor multiplicity was reduced by 67 or 65%, respectively. When the tea extract was given after the NNK-treatment period until the end of the experiment, 0.6% green tea extract decreased the tumor incidence and multiplicity by 30 and 85%, respectively. In this protocol, 0.6% black tea extract reduced tumor multiplicity by about 63% but did not significantly affect the tumor incidence. The results clearly demonstrated an inhibitory action of green tea and black tea on nitrosamine-induced tumorigenesis. 相似文献
105.
106.
Chun-Hsiung Huang Fang-Yuan Ho Hon-Ming Ma Chan-Tsung Yang Jiann-Jong Liau Hung-Chan Kao Tai-Horng Young Cheng-Kung Cheng 《Journal of orthopaedic research》2002,20(5):1038-1041
Osteolysis induced by ultrahigh molecular weight polyethylene wear debris has been recognized as the major cause of long-term failure in total joint arthroplasties. In a previous study, the prevalence of intraoperatively identified osteolysis during primary revision surgery was much higher in mobile bearing knee replacements (47%) than in fixed bearing knee replacements (13%). We postulated that mobile bearing knee implants tend to produce smaller sized particles. In our current study, we compared the particle size and morphology of polyethylene wear debris between failed mobile bearing and fixed bearing knees. Tissue specimens from interfacial and lytic regions were extracted during revision surgery of 10 mobile bearing knees (all of the low contact stress (LCS) design) and 17 fixed bearing knees (10 of the porous-coated anatomic (PCA) and 7 of the Miller/Galante design). Polyethylene particles were isolated from the tissue specimens and examined using both scanning electron microscopy and light-scattering analyses. The LCS mobile bearing knees produced smaller particulate debris (mean equivalent spherical diameter: 0.58 microm in LCS, 1.17 microm in PCA and 5.23 microm in M/G) and more granular debris (mean value: 93% in LCS, 77% in PCA and 15% in M/G). 相似文献
107.
Jing‐Long Huang Liang‐Shiou Ou Ching‐Hsiung Tsao Li‐Chen Chen Ming‐Ling Kuo 《Pediatric allergy and immunology》2002,13(6):426-433
T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69+, CD54+, and CD62L+ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3+ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69+ and CD54+ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy. 相似文献
108.
109.
Leo Sher Juan J Carballo Michael F Grunebaum Ainsley K Burke Gil Zalsman Yung-yu Huang J John Mann Maria A Oquendo 《Bipolar disorders》2006,8(5P2):543-550
Objectives: Bipolar disorder is a severe illness that is associated with suicidal behavior. A biological predictor of highly lethal suicide attempts in patients with bipolar disorder would be valuable. We hypothesized that cerebrospinal fluid (CSF) monoamine metabolite levels are related to lethality of suicide attempts in bipolar patients and examined the relation between CSF 5-hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) levels and maximum lethality of suicide attempts at baseline and during a 2-year follow up.
Methods: Twenty-seven bipolar depressed patients participated in the study. Demographic and clinical parameters were examined and recorded. Lumbar punctures were performed and CSF 5-HIAA, HVA, and MHPG were assayed by high-performance liquid chromatography with electrochemical detection. Following discharge, patients were evaluated after 3 months, 1 year, and 2 years. Each follow-up interview included an in-depth assessment of suicidal behavior during the intervening time period.
Results: Six subjects made suicide attempts during the 2-year follow-up. Bipolar patients who attempted suicide during the follow-up period had higher aggression and hostility scale scores compared to bipolar subjects who did not make a suicide attempt during the follow-up period. CSF 5-HIAA, HVA, and MHPG levels were negatively correlated with the maximum lethality of suicide attempts during the 2-year follow-up period.
Conclusions: Our finding is the first observation that CSF monoamine metabolite levels may be predictors of lethality of suicide attempts in patients with bipolar disorder. Further studies are necessary to answer the question whether CSF monoamine metabolite levels are clinically useful biochemical predictors of highly lethal suicide attempts or completed suicides. 相似文献
Methods: Twenty-seven bipolar depressed patients participated in the study. Demographic and clinical parameters were examined and recorded. Lumbar punctures were performed and CSF 5-HIAA, HVA, and MHPG were assayed by high-performance liquid chromatography with electrochemical detection. Following discharge, patients were evaluated after 3 months, 1 year, and 2 years. Each follow-up interview included an in-depth assessment of suicidal behavior during the intervening time period.
Results: Six subjects made suicide attempts during the 2-year follow-up. Bipolar patients who attempted suicide during the follow-up period had higher aggression and hostility scale scores compared to bipolar subjects who did not make a suicide attempt during the follow-up period. CSF 5-HIAA, HVA, and MHPG levels were negatively correlated with the maximum lethality of suicide attempts during the 2-year follow-up period.
Conclusions: Our finding is the first observation that CSF monoamine metabolite levels may be predictors of lethality of suicide attempts in patients with bipolar disorder. Further studies are necessary to answer the question whether CSF monoamine metabolite levels are clinically useful biochemical predictors of highly lethal suicide attempts or completed suicides. 相似文献
110.
H K Soong W C Parkinson S Bafna G L Sulik S C Huang 《Investigative ophthalmology & visual science》1990,31(11):2278-2282
The effects of an externally applied direct-current electric field on the movement of cultured rabbit corneal epithelial cells and stromal fibroblasts were studied. After a latency of approximately 20 minutes in an electric field, both epithelial cells and stromal fibroblasts became spindle shaped and underwent galvanotropism by aligning their long axes perpendicular to the applied electric field. The electric field stimulus thresholds for galvanotropic movements in epithelial cells and stromal fibroblasts were 4V/cm and 6 V/cm, respectively. After an additional latency of 30 minutes, both cell types manifested galvanotaxic movements: epithelial cells commenced migration in the cathodal (downfield) direction and stromal fibroblasts in the anodal (upfield) direction. For both types of cells, ruffled membranes and lamellipodia were abundant at the leading edges of migrating cells and cell processes underwent retraction at the trailing edges. At field strengths of above 10 V/cm, evidence of cellular damage (manifested by cellular rounding and detachment), attributable to the electric field treatment, was observed after 4 hours. These preliminary results suggest that galvanotaxic responses could be exploited clinically in the enhancement of corneal wound healing. 相似文献