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91.
由于病变和外伤等原因,使一些人眼球摘除,留下外现缺陷。医学上使用义眼台植入眼眶,在上面按装义眼以矫治外形。从前使用的义眼台用玻璃球或硅橡胶制作,使用中均有种类不同的缺点,即无生物活性、密度大等。医学界希望有新型医用材料临床应用。采用液态化学方法合成羟基磷灰石,使羟基磷灰石和微晶玻璃混匀,制成生物活性材料。生物材料和粘结剂、造孔剂,辅助剂一同制成生坯,以适当的温度焙烧成多孔结构义眼台。对材料进行了动物实验与临床应用。动物实验表明,材料具有优异的生物相容性和一定的生物活性。临床应用效果良好。本材料是制备义眼台的新材料。本文就材料研究、动物实验、义眼台的生产工艺进行了探讨。  相似文献   
92.
Ethanol-induced fatty liver in rats was attenuated by repeated running exercise, and the protective effect of exercise was associated with the synergistic expression of heat shock proteins (HSP72). Rats were placed in four groups of six. The two ethanol-fed groups of rats received a liquid diet (Lieber-DeCarli formulation) in which 36% of the calories were derived from ethanol. One group remained sedentary (S/E), whereas the other was trained to run on a rodent treadmill at a speed of 27 m/min, 1 hr/day, 5 days/week, for 7 weeks (R/E). Two other groups–one exercised as previously mentioned (R/C) and one sedentary (S/C)–received control-liquid diets in which the ethanol was isocalorically substituted with a dextran/maltose mixture. The degree of fatty infiltration in liver sections stained with hematoxylin and eosin was graded on a 0–4 scale and the data analyzed by ANOVA on ranks. Ethanol significantly induced fatty infiltration in the S/E group, whereas fatty infiltration in the livers of the R/E group was not different from the S/C group. Electrophoresis and Western blotting of liver homogenates demonstrated that HSP72 was not expressed in either the S/C or S/E groups and was only slightly expressed in the R/C group. The combination of exercise and ethanol, however, resulted in an elevated expression of HSP72 in the R/E group. The content of HSP73 was unaffected by any treatment.  相似文献   
93.
海口地区2000年临床分离菌耐药性监测   总被引:1,自引:1,他引:0  
目的:监测海口地区临床分离菌对抗菌药物的耐药状况。方法:采用VITEK微生物自动分析仪测定药敏。结果:2000年共收集临床分离菌1399株,革兰阳性球菌426株(30.5%),革兰阴性杆菌973株(69.5%),以铜绿假单胞菌、大肠杆菌、金黄色葡萄球菌、肺炎克雷伯杆菌最多见,所监测的细菌总体耐药率比国内其他地区偏高,且出现万古霉素耐药的表皮葡萄球菌和粪肠球菌。结论:海口地区的细菌耐药严重,控制细菌耐药成为当务之急。  相似文献   
94.
To evaluate the sensitivity of a polymerase chain reaction (PCR) assay using nested primers in detectingHelicobacter pylori, gastric tissue biopsy specimens were collected on endoscopy from 17 patients with a duodenal ulcer. DNA was extracted by phenol/chloroform treatment or boiling in water, and then subjected to a nested PCR using two primer pairs from the urease gene ofHelicobacter pylori. Fourteen of the 17 patients were positive forHelicobacter pylori using DNA samples extracted by either method. The PCR results correlated well with the results of an enzyme immunoassay to detect IgG antibody. However, there were two culture negative patients. The three PCR negative patients were both culture negative and serologically negative. DNA from 9 of the 14 patients was randomly selected and subjected to semiquantification by serial dilutions, and then PCR. The results showed that phenol/chloroform extraction yielded 10–1000 times more DNA than the boiling method. It is concluded that the PCR assay is a rapid and sensitive method for detectingHelicobacter pylori, and that phenol/chloroform extraction is superior to simple boiling in obtaining DNA samples for PCR.  相似文献   
95.
本文根据Svennerholm和蒋谷人等的方法略加改良,测定了蚌埠地区113例正常人,71例恶性肿瘤患者和82例非肿瘤疾病患者血清脂质结合唾液酸(LSA)的含量。正常值为12.4mg/dl(SD=±3.6mg/dl),71例不同肿瘤患者的平均值为28.2mg/dl(SD=±9.7mg/dl),阳性率为88.7%,82例非肿瘤疾病患者的平均值为16.82mg/dl(SD=±5.4mg/dl),假阳性率为17%。方法的灵敏度,重复性(平均CV=3.6%)和回收率(平均回收率=101.4%)测定结果是满意的。本研究的初步结果表明,血清LSA测定对肺癌、白血病、胃癌和食管癌具有一定的临床诊断价值。  相似文献   
96.
Osteoporosis and Coronary Atherosclerosis in Asymptomatic Postmenopausal Women   总被引:23,自引:9,他引:14  
Estrogen deficiency is a risk factor for osteoporosis and coronary artery disease. Osteoporosis can be evaluated by measuring bone mineral density (BMD). Coronary atherosclerotic burden can be evaluated by measuring coronary calcium using electron beam computed tomography (EBT) of the heart. We compared coronary calcium scores in 45 asymptomatic postmenopausal women with normal and low BMD. BMD of the lumbar spine and proximal femur was measured by dual X-ray absorptiometry (DXA), and coronary calcium was measured quantitatively by EBT. Women were divided into control, osteopenia, and osteoporosis groups based on the T score of the lumbar spine. Women were similar in age, years since menopause, height, weight, and body mass index (BMI). BMD ± SD (g/cm2) of L1–L4 was 0.96 ± 0.11, 0.83 ± 0.03, and 0.73 ± 0.05, in control, osteopenia, and osteoporosis group, respectively. The total coronary calcium score ± SD (relative units) was 41.9 ± 83.1, 115.1 ± 181.9, and 221.7 ± 355.4 for control, osteopenia, and osteoporosis group, respectively; the score was significantly higher in the osteoporosis than in the control group. This study provides initial data suggesting that women with osteoporosis may have a higher risk of developing coronary atherosclerosis.  相似文献   
97.
MK-679 (R(?)-3-((3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl)(3-(dimethylamino)-3-oxopropyl)thio)methyl)thio(propanoic acid) is a potent and specific LTD4-receptor antagonist. The disposition of MK-679 was investigated in a three-way crossover study in 12 healthy males receiving single intravenous doses of 75, 250, and 500 mg of MK-679. A greater than proportional increase in the area under the plasma concentration—time curve of MK-679 was observed with increase in dose. The plasma concentration data for each subject fitted well to the differential equations for a two-compartment model with linear tissue distribution and Michaelis-Menten elimination from the central compartment, indicating that the elimination of MK-679 in humans is saturable. In a previous study, the disposition of MK-679 in humans was also dose-dependent when given together with its S(+)-isomer, L-668,018. Thus, the disposition of MK-679 in humans is dose-dependent regardless of the presence of its stereoisomer. Also, the bioavailability of MK-679 was determined in six healthy males receiving simultaneously an oral dose of 250 mg of MK-679 and intravenous infusion of 1 mg 14C-MK-679. Results of this study indicate that the oral bioavailability of MK-679 is nearly quantitative.  相似文献   
98.
本文应用计算机辅助的角膜地形图系统TMS-1和角膜曲率计TOPCONOM-4同时测定了200例(278眼)的角膜地形图和中央角膜屈光状态。比较了角膜地形图的模拟角膜曲率SIMK值和角膜曲率计的垂直和水平屈光度。结果显示,白内障术前组116例150眼的SIMK平均值分别为44.22D(垂直轴)和44.26D(水平轴),角膜曲率计的中央屈光度垂直轴平均为44.16D,水平轴为44.23D。统计学处理表明,2种组方法的结果之间差异无显著性(P>0.05),第2种术后组67例90眼的SIMK平均值分别为46.37D(垂直轴)和43.06D(水平轴),角膜曲率计的中央屈光度垂直轴平均为46.09D,水平轴平均为42.88D,统计学处理二种方法的结果之间差异无显著性(P>0.05)。研究提示,角膜地形图系统的模拟角膜曲率SIMK值和角膜曲率计的屈光度无论在白内障手术前还是在手术后其结果是一致的,临床应用具有同等的价值。但是,当角膜中央屈光度异常范围小于3毫米,角膜混浊,角膜严重不规则散光时,角膜曲率计不能满足临床需要。而计算机辅助的角膜地形图系统则具有极大的诊断及检测价值。眼科学报 1994;10:85—89。  相似文献   
99.
报告14例后房型人工晶体植入术后继发青光眼患者,男性8例,女性6例。均为单眼发病,其中10例发生在术后1个月以内,另4例发生在1~3年以后。其中开角型8例,闭用型6例。7例经抗青光眼药物治疗可控制眼压,4例用激光治疗,另3例需行抗青光眼手术。治疗前矫正视力达0.5以上者为28%,治疗后矫止视力达0.5以上增加至50%。所有病例均眼压控制良好、视力不良原因为青光眼世视神经萎缩,提示早期发现的重要性。  相似文献   
100.
复治矽肺结核化疗效果观察   总被引:3,自引:0,他引:3  
我们自1980~1988年对79例复治矽肺结核进行化疗。其中绝大多数为慢性纤维化空洞性病例,均经细菌学证实,并由尘肺诊断组认定为矽肺合并结核。本组病例分别以KM、INH、RFP、PZA,或SM、INH、RFP、EB联合,分两阶段治疗18个月,获痰菌阴转79.2%,其中KHRZ与SHRE组分别为93.9%与68.2%(P<0.05)。自疗程结束追踪2~8年,其细菌复阳率分别为6.45%和10.0%(P>0.1)。并对影响其过去治疗失败的原因及对策进行了讨论。  相似文献   
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