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排序方式: 共有1498条查询结果,搜索用时 31 毫秒
21.
玻璃体切除术治疗外伤性眼内炎62例 总被引:3,自引:1,他引:2
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿… 相似文献
22.
RAJVIR BHALWAR HS SANDHU RC AHUJA GK SINGH RP MISRA 《Medical Journal Armed Forces India》1994,50(3):175-180
A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude 相似文献
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The prevalence of microalbuminuria was assessed in 50 patients of non-insulin dependent diabetes mellitus. The mean age of patients was 52.1 ± 11.6 years and the duration of diabetes was 8.3 ± 6.8 years. Twenty (40%) patients had microalbuminuria. Microalbuminuria was more common in patients with a longer duration of diabetes (more than 5 years), a poor glycaemic control, and higher systolic blood pressure.KEY WORDS: Microalbuminuria, Diabetes mellitus, Diabetic nephropathy, Chronic renal failure 相似文献
25.
Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation. 相似文献
26.
Adsorption/desorption of human serum albumin on hydroxyapatite: a critical analysis of the Langmuir model.
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M J Mura-Galelli J C Voegel S Behr E F Bres P Schaaf 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(13):5557-5561
We studied the adsorption of human albumin onto synthetic hydroxyapatite, using a radiotracer technique and a special flow cell. Adsorption was studied under various conditions corresponding to different thermodynamic paths. It appears that (i) as is the usual case, the isotherms obtained within a short time range (a few hours) do not correspond to a true equilibrium situation; (ii) when the adsorption process is followed for longer times, which is necessary at low bulk concentrations, one always reaches the plateau surface adsorption; (iii) this plateau value is independent of the "history" of the adsorption process and corresponds well to the jamming limit predicted by the random sequential adsorption model; and (iv) surface denaturation, leading to enhanced surface binding and thus decreasing desorption constants, is the important phenomenon that can partly and qualitatively explain our observations. Its time dependence, however, remains to be clarified. 相似文献
27.
Edgardo Rivera Vicente Valero Deborah Francis Aviva G Asnis Larry J Schaaf Barbara Duncan Gabriel N Hortobagyi 《Clinical cancer research》2004,10(6):1943-1948
PURPOSE: We conducted a pilot study assessing the effects of the selective estrogen receptor modulator, tamoxifen, on the pharmacokinetics, pharmacodynamics, and safety of the steroidal, irreversible aromatase inhibitor (AI), exemestane, when the two were coadministered in postmenopausal women with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients with documented or unknown hormone receptor sensitivity were eligible. Patients received oral exemestane at 25-mg once daily. Starting day 15, oral tamoxifen at 20-mg once daily, was added. We measured plasma concentrations of exemestane, estrone, estrone sulfate, and estradiol after 14 days of exemestane monotherapy and after approximately 4 weeks of combination therapy. The incidence and severity of adverse events were assessed by physical examination and patient reporting. RESULTS: We treated 18 patients. All had received prior chemotherapy and/or hormonal therapy, eight and six, respectively, with single-agent selective estrogen receptor modulators or irreversible aromatase inhibitors; no hormonal therapy was given within 30 days of study entry. Plasma exemestane concentrations and estrone, estrone sulfate, and estradiol suppression were unchanged after approximately 4 weeks of tamoxifen coadministration. All drug-related adverse events were grades 1 or 2; none was unexpected. Although not a formal study end point, antitumor activity was noted, with two partial responses and four cases of stable disease among 17 evaluable patients after a 9-month median follow-up (range, 2.5-19 months). CONCLUSIONS: This pilot study provides evidence that coadministration of tamoxifen does not affect exemestane pharmacokinetics or pharmacodynamics and that the combination is well-tolerated and active. Further clinical investigation is warranted. 相似文献
28.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
29.
B J Marais Susan van Zyl H S Schaaf M van Aardt R P Gie N Beyers 《Archives of disease in childhood》2006,91(9):762-765
BACKGROUND: Current international guidelines recommend 6-9 months of isoniazid (INH) preventive chemotherapy to prevent the development of active tuberculosis in children exposed to a susceptible strain of M tuberculosis. However, this is dependent on good adherence and retrospective studies have indicated that adherence to unsupervised INH preventive chemotherapy is poor. AIM: To prospectively document adherence to six months of unsupervised INH monotherapy and outcome in children with household exposure to an adult pulmonary tuberculosis index case. METHODS: From February 2003 to January 2005 in two suburbs of Cape Town, South Africa, all children <5 years old in household contact with an adult pulmonary tuberculosis index case were screened for tuberculosis and given unsupervised INH preventive chemotherapy once active tuberculosis was excluded. Adherence and outcome were monitored. RESULTS: In total, 217 index cases from 185 households were identified; 274 children <5 years old experienced household exposure, of whom 229 (84%) were fully evaluated. Thirty eight children were treated for tuberculosis and 180 received preventive chemotherapy. Of the children who received preventive chemotherapy, 36/180 (20%) completed > or =5 months of unsupervised INH monotherapy. During the subsequent surveillance period six children developed tuberculosis: two received no preventive chemotherapy, and four had very poor adherence. CONCLUSION: Adherence to six months of unsupervised INH preventive chemotherapy was poor. Strategies to improve adherence, such as using shorter duration multidrug regimens and/or supervision of preventive treatment require further evaluation, particularly in children who are at high risk to progress to disease following exposure. 相似文献
30.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献