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41.
本文对17例肾病综合征(NS)患儿和15例健康对照组儿童血红细胞磷脂过氧化氢谷胱甘肽过氧化物酶(PHGPx)活力,脂溶性荧光色素(LSFP)含量进行了研究。结果表明,NS急性期PHGPx活力明显降低.LSFP含量增加;恢复期PHGPx活力较急性期明显提高,但仍低于正常对照组,LSFP虽较急性期下降,但仍高于正常对照组。说明NS存在PHGPx和LSFP的改变,但可逐渐恢复。 相似文献
42.
M K Song W Y Shin N F Adham N V Costea 《The American journal of clinical nutrition》1989,49(4):701-707
The effects of different amounts of dietary zinc on the Zn absorption rate and on Zn, calcium and magnesium concentrations in tissues of MOPC 104E tumor-bearing Balb/c mice were determined. The Zn absorption rate was inversely related to the amounts of Zn in their diets and was lower than that of nontumor-bearing control mice fed a laboratory mice chow. Zn concentrations of tumor-bearing mice were also low compared with control mice but tumor Zn concentrations, regardless of the concentrations of Zn in the diets, were higher than those of normal tissues of the host other than the pancreas. Ca concentrations in tumor and tissues of tumor-bearing mice were higher than in control animals but Mg concentrations in tissues of tumor-bearing mice appeared to be similar to those of control mice. Results suggest that tumor-bearing mice have a lower intestinal Zn absorption capacity and a higher Zn uptake rate causing other tissues to become hypozincemic and hypercalcemic. 相似文献
43.
Detection of cell apoptosis by MTT assay.] 总被引:1,自引:0,他引:1
Chun-Qiong Feng Wen-Li Ma Yan-Bing Song Qiu-Ye Guo Qing-Hua Wu Wen-Ling Zheng 《第一军医大学学报》2002,22(3):262-263
OBJECTIVE: To study the feasibility of using MTT assay to detect cell apoptosis. METHODS: K562 cells were grown in RPMI 1640 medium supplemented with 10% calf serum and 4 micromol/L arsenic trioxide. Apoptosis was induced in the cultured cells by As2O3, and the cells were detected with optical microscope, DNA gel electrophoresis and MTT staining respectively. RESULT: MTT staining could also accurately detect cell apoptosis, by which the apoptotic cells were easily distinguished from normal cells and dead cells. CONCLUSION: MTT staining is simple, convenient and practical for detecting cell apoptosis. 相似文献
44.
In order to clarify the reported discrepancies in S100 alpha protein and mRNA distribution in rat tissues, a rat S100 alpha cDNA has been isolated and this species homologous probe along with a rat S100 beta cDNA probe has been used to examine S100 mRNA expression in rat tissues. Although the rat S100 alpha cDNA was missing approximately 30 nucleotides of coding sequence, only 4 conservative changes in amino acid sequence were observed when the deduced amino acid sequence was compared to the bovine S100 alpha amino acid sequence. Thus, S100 alpha proteins, like S100 beta proteins, are highly conserved among species. All nineteen of the tissues examined (including cerebrum and cerebellum) contained S100 alpha mRNA. In addition, S100 beta mRNA was detected in thirteen of the nineteen tissues examined. These results are in agreement with previous protein distribution studies and further demonstrate that S100 proteins are not brain-specific and are expressed in a large number of tissues. Although S100 alpha and S100 beta mRNAs were detected in rat tissues which had previously been reported to contain S100 alpha and S100 beta protein, a direct correlation between the protein and mRNA levels were not observed, suggesting that different mechanisms regulate S100 expression in various tissues. S100 alpha exhibited a single similar size mRNA species (0.5 Kb) in all tissues examined, as did S100 beta (1.5 Kb), suggesting that the individual S100 proteins are expressed as single mRNA and protein products in rat tissues. 相似文献
45.
Based on the experience of the author and an intensive study of the titles of English medical papers written by authors in English-speaking countries, the characteristics and styles of the titles were expounded with well-selected examples. The paper also introduces some practical skills to write good English titles and enumerates some frequently used structures and expressions, which might be helpful for potential Chinese contributors to medical journals. 相似文献
46.
Inhibition of the expression of lysyl oxidase and its substrates in cadmium-resistant rat fetal lung fibroblasts. 总被引:3,自引:0,他引:3
Yinzhi Zhao Song Gao Iih-Nan Chou Paul Toselli Phillip Stone Wande Li 《Toxicological sciences》2006,90(2):478-489
Copper (Cu)-dependent lysyl oxidase (LO) catalyzes crosslinking of collagen and elastin stabilizing the extracellular matrix (ECM). Chronic inhalation of cadmium (Cd), a toxic metal, induces emphysema. To probe mechanisms of Cd injury to the lung, we developed Cd-resistant (CdR) cells from rat fetal lung fibroblasts (RFL6) by chronic exposure to CdCl(2) from 1 to 40 microM and further examined their expressions of LO, LO substrates, and Cu-scavenging thiols. Levels of cellular thiols, metallothionein, and glutathione in CdR cells were elevated to 13.0- and 3.2-fold of parental controls, respectively, whereas LO mRNA and protein levels were markedly reduced in these cells, with catalytic activity declining to only 16% of the parental control. A conspicuous 52 kDa species rather then the normal 50 kDa proenzyme appeared in the CdR cell extract but not in the conditioned medium, which was codistributed with the endoplasmic reticulum marker [DiOC5(3)] within the cell, implying the Cd-induced 52 kDa species as a product of an abnormal LO-processing defect in secretion. Addition of Cu into CdR cell cultures enhanced the expression of LO mRNA, protein and catalytic activities reflecting limitation of Cu bioavailability for LO in these cells. With inhibition of LO, CdR cells also displayed downregulation of collagen and elastin, substrates of LO. Restoration of collagen synthesis by exposure of CdR cells to purified LO or Cu suggests that inhibition of LO and limitation of Cu cofactor by Cd, as key phenotype changes, accelerated collagen and elastin damage, a critical event pertinent to emphysema pathogenesis. 相似文献
47.
IC Uluibau Postgraduate Student T. Jaunay Registrar † AN Goss Professor Director ‡ 《Australian dental journal》2005,50(S2):S74-S81
Background : Severe odontogenic infections are serious potentially lethal conditions. Following the death of a patient in the authors' institution this study was initiated to determine the risk factors, management and outcome of a consecutive series of patients.
Methods : All patients admitted to the Royal Adelaide Hospital under the care of the Oral and Maxillofacial Surgery Unit with odontogenic infections in calendar year 2003 were investigated. Detailed information relative to their pre-presentation history, surgical and anaesthetic management and outcome was obtained and analysed.
Results : Forty-eight patients, 32M, 16F, average age 34.5, range 19 to 88 years were treated. All presented with pain and swelling, with 21 (44 per cent) having trismus. Forty-four (92 per cent) were as a result of dental neglect and four (8 per cent) were regular dental patients having endodontic treatment which failed. Of those known to have been treated prior to presentation, most had been on antibiotics. Most patients had aggressive surgical treatment with extraction, surgical drainage, high dose intravenous antibiotics and rehydration. The hospital stay was 3.3 (range 1–16) days. Patients requiring prolonged intubation and high dependency or intensive care (40 per cent) had longer hospitalization. No patient died and all fully recovered.
Conclusion : Severe odontogenic infections are a serious risk to the patient's health and life. Management is primarily surgical with skilled anaesthetic airway management. Antibiotics are required in high intravenous doses as an adjunct and not as a primary treatment. 相似文献
Methods : All patients admitted to the Royal Adelaide Hospital under the care of the Oral and Maxillofacial Surgery Unit with odontogenic infections in calendar year 2003 were investigated. Detailed information relative to their pre-presentation history, surgical and anaesthetic management and outcome was obtained and analysed.
Results : Forty-eight patients, 32M, 16F, average age 34.5, range 19 to 88 years were treated. All presented with pain and swelling, with 21 (44 per cent) having trismus. Forty-four (92 per cent) were as a result of dental neglect and four (8 per cent) were regular dental patients having endodontic treatment which failed. Of those known to have been treated prior to presentation, most had been on antibiotics. Most patients had aggressive surgical treatment with extraction, surgical drainage, high dose intravenous antibiotics and rehydration. The hospital stay was 3.3 (range 1–16) days. Patients requiring prolonged intubation and high dependency or intensive care (40 per cent) had longer hospitalization. No patient died and all fully recovered.
Conclusion : Severe odontogenic infections are a serious risk to the patient's health and life. Management is primarily surgical with skilled anaesthetic airway management. Antibiotics are required in high intravenous doses as an adjunct and not as a primary treatment. 相似文献
48.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献
49.
青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究 总被引:1,自引:0,他引:1
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。 相似文献
50.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献