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91.
Determination of the concentration of osteocalcin in rat serum is frequently performed using a commercially available radioimmunoassay
(RIA). However, this assay takes 3 days to complete, uses radioactive material, and has a narrow linear range. The limited
range of the RIA makes it necessary to test multiple dilutions of the sample which frequently results in values that differ,
depending on the dilution. In order to overcome these limitations, we have developed an ELISA that utilizes the same standards
and anti-rat osteocalcin antiserum, as is used in the RIA. The principle of the ELISA is that the osteocalcin in the sample
competes with osteocalcin previously immobilized on a microtiter plate to bind to the available anti-rat osteocalcin antibodies.
The amount of antibody bound to the immobilized osteocalcin is determined colorimetrically using a secondary antibody coupled
to alkaline phosphatase. This ELISA has a three-log linear response with a sensitivity of 0.1–0.15 ng/ml and intra- and interassay
coefficient of variance (CV) values of less than 10%. Most importantly, the assay is rapid and only requires a 2-hour incubation
of the sample with the antiserum. The incubation time is important since we and others have observed a significant decrease
in the osteocalcin level from serum samples incubated for long periods of time with the antiserum, presumably due to degradation
of the osteocalcin. In general, the commercially available RIA gives osteocalcin values that are one-half to one-fourth that
of the ELISA because the RIA requires a 48-hour incubation time.
Received: 14 November 1997 / Accepted: 9 July 1998 相似文献
92.
93.
1-N HAPA gentamicin B, a new aminoglycoside active against gentamicin resistant isolates--activity compared to other aminoglycosides. 总被引:1,自引:0,他引:1
1-N HAPA gentamicin B is a new aminoglycoside active against most Enterobacteriaceae, Pseudomonas aeruginosa and Staphylococcus aureus. Among 504 clinical isolates at a concentration of 12.5 microgram/ml all Staph. aureus, Escherichia coli, Klebsiella, Enterobacter, Proteus rettgeri, Providencia and 78% of Pseudomonas, 86% of Proteus morganii were inhibited. Like other aminoglycosides, the activity was greatest at an alkaline ph and reduced by high cations concentrations. 1-N HAPA gentamicin B was equal in activity to amikacin against both gentamicin-sensitive and resistant isolates. It inhibited bacteria containing many of the aminoglycoside inactivating enzymes. When combined with carbenicillin it inhibited in a synergistic manner many Gram-negative bacteria, particularly Pseudomonas and Serratia. 相似文献
94.
Cyclopenta-polycyclic aromatic hydrocarbons (cyclopenta-PAHs) are a group of compounds that have been detected as environmental pollutants. Perturbation molecular orbital (PMO) calculations on their presumed ultimate carcinogenic metabolites, the cyclopenta-PAH expoxides, predict that they may have a greater biological hazard than the classic PAHs. 相似文献
95.
Fourteen points superficial bloodflow (SBF) of the skin and tongue in 55 patients with acute myocardial infarction (AMI) were measured at 12, 24, 36, 48, 60 hours and 3, 5, 7, 10, 14, 21, 28 days after AMI by LDF (PF2). The dynamic study on multiple points SBF of 576 times showed that (1) The mean SBF of skin was 1.0 +/- 0.04 (V) at 12 hours after AMI. It occupied 70.5% in the normal control. After therapy at 48 hours of AMI, the mean SBF was increased to 1.20 +/- 0.03 (V), and approximated 85.9% of the control. (2) The mean SBF in patients with cardiogenic shock was 1.04 +/- 0.05 (V), and it was significantly lower than that without complications (P less than 0.01). The mean SBF showed a negative correlation with the nailfold microcirculatory values (P less than 0.0025). There was a negative correlation between "Tanzhong" SBF and cardiac muscle enzyme CPK, GOT, LDH (P less than 0.05). (3) The SBF of acupuncture point "Tanzhong, Erxin" related to the heart might more sensitively represent the cardiac condition in AMI. (4) The SBF of tongue was negatively correlated with GOT (P less than 0.05). (5) Continual peripheral microcirculatory observation and electrocardiographic monitoring would be helpful in the diagnosis and treatment of earlier complications of AMI in order to reduce the mortality. 相似文献
96.
In our series of 256 nonepithelial tumors involving the nasal cavity, paranasal sinuses and nasopharynx, 21 were apparently primary malignant lymphomas, including 17 ordinary lymphomas and 4 cases of "midline malignant reticulosis." Of the 15 patients who had ordinary lymphomas and had adequate follow-up, 8 died of lymphoma, 4 were living with disseminated disease, 1 died of other causes with persistent lymphoma and only 2 (13%) had no evidence of recurrence at 8 and 9 years after diagnosis. The tumor was controlled in its primary site by radiotherapy in 13 of 14 patients; however, all but 2 of these patients eventually developed disseminated disease. Of the 3 patients who had midline malignant reticulosis (MMR) and had adequate follow-up, all died of disease. MMR represents an unusual variant of malignant lymphoma and often produces the clinical picture of lethal midline granuloma. 相似文献
97.
目的 研究可溶性血管细胞黏附分子 1(solublevascularcelladhesionmolecule - 1,sVCAM - 1)在妊高征发病中的作用。方法 用酶联免疫吸附法 (ELISA)测定 6 7例孕妇血清中sVCAM - 1水平 ,其中正常妊娠组 15例 ,妊高征组 5 2例。结果 中、重度妊高征患者血中sV CAM - 1水平显著高于正常妊娠组 (P <0 .0 1) ;轻度妊高征患者与正常妊娠组相比 ,虽无统计学差异 ,但有升高趋势 ;妊高征组产后该指标下降 ,与正常妊娠组比较无显著性差异 (P >0 0 5 )。sVCAM - 1浓度与平均动脉压呈正相关 (r =0 .5 4 2 ,P <0 .0 1)。结论 妊高征患者血中sVCAM - 1水平升高 ,表明内皮细胞损伤在妊高征的发病中起重要作用。 相似文献
98.
目的:探索上海地区农民人群中α-雌激素受体基因(ER-α)及芳香烃受体基因(Ahr)不同基因形态和老年痴呆症高发风险的可能联系.方法:分别以PCR—RFLP和AS—PCR方法分析一组老年痴呆症患者(n=52)ER-α基因及Ahr基因的多态位点,同一地区的健康人群(n=125)为对照.结果:Alzheimer症病人ER-α基因两个位点突变形态频率显著高于对照人群(Pvu Ⅱ位点:P=0.023,OR=2.94,95%CI 1.13—7.71;Xba I位点:P=0.046,0R=2.28,95% CI 1.003—5.17).Ahr G1721A位点基因型频率在病人组和对照组间无显著差异.结论:ER-α基因多态性可能与Alzheimer症易感性个体差异有关,本工作不支持Ahr基因多态性与老年痴呆症高发风险间的可能关联. 相似文献
99.
Objective Discussion of diagnosis, treatment and prognosis of non-palpable TO breast cancer.
Methods Between 1978 and 1997, 9,980 female patients with operable breast cancer were treated surgically, of which 276 were determined
to have TO breast cancer. Most TO breast cancers could be detected promptly with careful examination of presenting symptoms,
such as nipple discharge, local thickening of the breast, nipple erosion, nipple retraction and postmenopausal mastalgia,
while 12 cases were detected by routine mammography of the contralateral breast.
Results All patients were treated surgically and their tissue subjected to histopathological examination. Most cases (73.0%) were
noninvasive or early invasive carcinoma. Axillary lymph nodes metastases were found in 7.69% of 234 mastectomy cases.
Conclusion The survival rate was significantly increased if the tumor was in an early stage. The 5-, 10-, 15-years survival rates were
98.1%, 94.6% and 90.3%, respectively. 相似文献