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151.
RW Nims RA Lubet SD Fox CR Jones PE Thomas AB Reddy TA Kocarek 《Canadian Metallurgical Quarterly》1998,53(6):455-477
In this study the pharmacodynamics were characterized of rat hepatic cytochrome P-450 2B (CYP2B) induction by the pesticide DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] and its metabolites DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], which is bioretained, and DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane], which is metabolized further and therefore less prone to bioaccumulate. DDT, DDE, and DDD were each found to be pure phenobarbital-type cytochrome P-450 inducers in the male F344/NCr rat, causing induction of hepatic CYP2B and CYP3A, but not CYP1A. The ED50 values for CYP2B induction (benzyloxyresorufin O-dealkylation) by DDT, DDE, and DDD were, respectively, 103, 88, and > or = 620 ppm in diet (14 d of exposure). The efficacies (Emax values) for induction of benzyloxyresorufin O-dealkylation by DDT, DDE, and DDD were 24-, 22-, and > or = 1-fold, respectively, compared to control values. The potencies of the three congeners for CYP2B induction appeared also to be similar, with EC50 values (based on total serum DDT equivalents) of 1.5, 1.8, and > or = 0.51 microM, respectively. The EC50 values based on DDT equivalents in hepatic tissue were 15, 16, and > or = 5.9 micromol/kg liver tissue, respectively. In primary cultures of adult rat hepatocytes, DDT, DDE, and DDD each displayed ability to induce total cellular RNA coding for CYP2B (ED50 values of 0.98, 0.83, and > or = 2.7 microM, respectively). These results suggest that DDT, DDE, and DDD each possess a high degree of intrinsic CYP2B-inducing ability for rat liver, despite marked differences in bioretention among the congeners. 相似文献
152.
The serine protease thrombin is a key enzyme in the control of blood coagulation and displays numerous other effects on platelet, endothelial and smooth muscle cell function. The pre-eminence of thrombin in the coagulation cascade has made the enzyme a popular drug target in the search for more clinically acceptable and safe anti-coagulants. This concept has been particularly strengthened by the demonstration that direct inhibitors of thrombin such as Revasc are clinically effective. A number of low molecular weight thrombin inhibitors have now been described in the literature although to date because of their inherent low bioavailability compounds have been limited to the parenteral route of administration. The introduction of appropriate pharmacokinetic properties into these first generation thrombin inhibitors has been problematic despite intensive research in this area. However, the first pre clinical examples of direct thrombin inhibitors possessing good oral bioavailability is now emerging. This review updates current developments in the progress towards the discovery of orally available thrombin inhibitors and suggests that the first clinical validation of drugs from this field is imminent. 相似文献
153.
154.
OBJECTIVE: To determine the limits of agreement between the cardiac output and volumetric data estimated by impedance cardiography with the cardiac output determined by thermodilution and the left ventricular ejection fraction and end-diastolic volume estimated from left ventriculography. DESIGN: A prospective study. SETTING: The cardiac catheterization laboratory of a university-affiliated teaching hospital. PATIENTS: Twenty-four patients with coronary artery disease undergoing elective left- and right heart catheterization. INTERVENTIONS: Cardiac output was measured by the thermodilution method and the ejection fraction and left ventricular volumetric data were determined by ventriculography. These same measurements were obtained by simultaneously performed impedance cardiography using a commercially available bioimpedance device. MEASUREMENTS AND MAIN RESULTS: The patients' mean cardiac output was 4.6 +/- 1.7 L/min by bioimpedance and 5.0 +/- 1.1 L/min by thermodilution. The limits of agreement between the two methods was -4.1 to 3.5 L/min. The 95% confidence intervals for the lower and upper limits of agreement were -2.7 to -5.5 L/min and 2.1 to 4.9 L/min, respectively. The mean ejection fraction was 63 +/- 8% by bioimpedance and 53 +/- 15% by ventriculography. The limits of agreement between the ejection fraction estimated by bioimpedance and ventriculography was -35% to 37%. The 95% confidence intervals for the lower and upper limits of agreement were -22% to -48% and 24% to 50%, respectively. The mean left ventricular end-diastolic volume was 108 +/- 47 mL, as estimated by bioimpedance, and 121 +/- 35 mL, as estimated by ventriculography. The limits of agreement between the left ventricular end-diastolic volume as estimated by bioimpedance and ventriculography was -139 to 113 mL. The 95% confidence intervals for the lower and upper limits of agreement were -184 to -94 mL and 68 to 158 mL, respectively. CONCLUSIONS: The 95% confidence range defining the limits of agreement between cardiac output and volumetric data estimated by bioimpedance, with the cardiac output measurement by thermodilution and the volumetric data estimated from left ventriculography, were wide, making the degree of agreement clinically unacceptable. In the opinion of the authors, impedance cardiography should not replace invasive hemodynamic monitoring at this time. 相似文献
155.
R García-Miralles Grávalos J Benejam Gual PE Moneva J Oliva Encina LA Rioja Sanz 《Canadian Metallurgical Quarterly》1998,22(6):542-545
Castleman's disease (angiofollicular hyperplasia of the lymphatic nodes) can exceptionally appear as a retroperitoneal mass of difficult differential diagnosis relative to other malignant retroperitoneal masses. Because of its rarity, one case report of a retroperitoneal mass with histologic study corresponding to Castleman's disease is contributed. A revision of the different histologic varieties of Castleman's disease, specific treatment and prognosis is included. 相似文献
156.
PE Alonso E Bescansa J Salas J de Haro A Redondo LF Rioja 《Canadian Metallurgical Quarterly》1995,48(8):564-568
This paper reports two cases of orbital apex syndrome. The most salient clinical signs, ophthalmoplegia and eyelid ptosis, arose from perineural spread of facial squamous cell carcinomas that were previously excised with tumour-free surgical margins and exhibited no signs of local or other regional recurrence. The interest of these two cases lies in the fairly rare occurrence of this type of tumour spread and the highly aggressive nature of the tumour, unequivocal diagnosis of which usually arrives too late for a surgical solution. Awareness of the possibility of such perineural spread may allow the clinician to establish an early diagnosis and thus undertake radical surgery, thereby increasing the likelihood of success in combination with postoperative radiotherapy. 相似文献
157.
158.
Amplification of human papillomavirus (HPV) DNA by L1 consensus primer systems (e.g., MY09/11 or GP5(+)/6(+)) can detect as few as 10 to 100 molecules of HPV targets from a genital sample. However, genotype determination by dot blot hybridization is laborious and requires at least 27 separate hybridizations for substantive HPV-type discrimination. A reverse blot method was developed which employs a biotin-labeled PCR product hybridized to an array of immobilized oligonucleotide probes. By the reverse blot strip analysis, genotype discrimination of multiple HPV types can be accomplished in a single hybridization and wash cycle. Twenty-seven HPV probe mixes, two control probe concentrations, and a single reference line were immobilized to 75- by 6-mm nylon strips. Each individual probe line contained a mixture of two bovine serum albumin-conjugated oligonucleotide probes specific to a unique HPV genotype. The genotype spectrum discriminated on this strip includes the high-risk, or cancer-associated, HPV genotypes 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 55, 56, 58, 59, 68 (ME180), MM4 (W13B), MM7 (P291), and MM9 (P238A) and the low-risk, or non-cancer-associated, genotypes 6, 11, 40, 42, 53, 54, 57, 66, and MM8 (P155). In addition, two concentrations of beta-globin probes allowed for assessment of individual specimen adequacy following amplification. We have evaluated the performance of the strip method relative to that of a previously reported dot blot format (H. M. Bauer et al., p. 132-152, in C. S. Herrington and J. O. D. McGee (ed.), Diagnostic Molecular Pathology: a Practical Approach, (1992), by testing 328 cervical swab samples collected in Digene specimen transport medium (Digene Diagnostics, Silver Spring, Md.). We show excellent agreement between the two detection formats, with 92% concordance for HPV positivity (kappa = 0.78, P < 0.001). Nearly all of the discrepant HPV-positive samples resulted from weak signals and can be attributed to sampling error from specimens with low concentrations (<1 copy/microliter) of HPV DNA. The primary advantage of the strip-based detection system is the ability to rapidly genotype HPVs present in genital samples with high sensitivity and specificity, minimizing the likelihood of misclassification. 相似文献
159.
PE Verweij Z Erjavec W Sluiters W Goessens M Rozenberg-Arska YJ Debets-Ossenkopp HF Guiot JF Meis 《Canadian Metallurgical Quarterly》1998,36(6):1612-1616
The intra- and interlaboratory reproducibilities of a commercial sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of Aspergillus galactomannan in serum (Platelia Aspergillus; Sanofi Diagnostics Pasteur, Marnes-La-Coquette, France) were evaluated in six laboratories of university hospitals. Twenty serum samples were obtained from 12 neutropenic patients including 6 with invasive aspergillosis. These samples were blinded and sent to each center together with eight blinded ELISA-negative serum samples spiked with known concentrations of galactomannan. The centers were provided with ELISA microtiter plates from a single batch and a detailed protocol. Ten clinical samples showed ELISA reactivity, while 10 samples were ELISA negative. The mean coefficient of variation (CV) of the optical density values was 4.24% within a single assay and 25.6% between runs. The interassay CV of the ratios for the serum samples tested was 18.6%. Analysis of ordinal interpretation of the ELISA result (i.e., negative, gray zone, or positive) showed excellent reproducibility. Recalculation of the cutoff values for positive and negative samples suggested that the cutoff level recommended by the manufacturer could be lowered from 1.0 to 0.8 for negative samples and from 1.5 to 1.0 for positive samples. The intra- and interlaboratory reproducibilities were excellent when the ELISA results were interpreted as ordinal data, but considerable variation in optical density values and, to a lesser extent, in the ratios for the serum samples tested, was observed between runs. High assay variability was also found for serum samples spiked with known concentrations of galactomannan. Therefore, antigen titers in serum samples from a single patient, measured in different runs, should be compared with caution. 相似文献
160.
MJ Borel PE Williams K Jabbour D Levenhagen E Kaizer PJ Flakoll 《Canadian Metallurgical Quarterly》1998,22(5):280-285
There is no consensus of opinion on the treatment of hypertensive putaminal hemorrhage (HPH), especially in patients older than 65 years. The purpose of this study was to study the surgical outcome of HPH in patients older than 65 years while considering mortality and activity of daily life. Among eighty-three patients aged 65 or older with HPH, fifty-one patients received only medical treatment and 32 were operated upon to remove the hematoma. Each patient was measured by the intracerebral hemorrhage-intracranial hemorrhage grading scale (ICH Grade) which used the sum of eye opening and motor response scores derived from Glasgow Coma Scale. The cubic content of the HPH was calculated from measurement of maximum width (X), length (Y) and height (Z), and the hematoma volume taken as 1/2 that volume (X. Y. Z/2). The acute mortality in surgically treated group was 40.6% and three patients died during the follow-up period from one to six months after the operation. Determinant for the prognosis was the ICH grade and the volume of the hematoma. Patients who returned to ADL 1 and 2 (good recovery) after surgical treatment were 40.0% in ICH Grade I, 16.7% in ICH Grade II, and 20.0% in ICH Grade III. Among those patients who were in ICH Grade IV, none had good recovery. The acute mortality was zero in ICH Grade I, 16.7% in ICH Grade II, 40.0% in ICH Grade III, and 62.5% in ICH Grade IV. The crucial size was 60 ml with a mortality of 77.8% for hematomas larger and 39.1% for hematomas smaller than that. From our lim ited experience, we learned that operation in elderly patients with HPH was considered only in patients with hematomas between 20 to 60 ml, with a high operative mortality and only one-fourth having a good recovery postoperatively. 相似文献