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BACKGROUND: To compare the efficacy of intravenous (iv) nicardipine with nitroglycerin for the treatment for patients with perioperative hypertension. METHODS: Forty patients with perioperative hypertension randomly divided into two groups were treated with intravenous calcium entry blocker, nicardipine, or vasodilator, nitroglycerin. Haemodynamic measurements including mean arterial and pulmonary arterial pressure, central venous and pulmonary capillary wedge pressure, and cardiac output were recorded; peripheral and pulmonary vascular resistance were calculated. RESULTS: Both medications were effective in reducing blood pressure and controlling haemodynamics. During the maintenance by continuous iv infusion, nicardipine controlled hypertension more rapidly than nitroglycerin (nicardipine 10.5 +/- 2.5 min and nitroglycerin 18.7 +/- 2.8 min, p < 0.05) without significant alteration in heart rate. The total frequency of dose adjustments required to achieve therapeutic response was significantly less in the nicardipine-treated group (2.5 +/- 0.3 for nicardipine and 6.2 +/- 1.4 for nitroglycerin, p < 0.05). Incidence of hypotensive episodes during the infusion were observed in both groups [nicardipine 5% (1/20) and nitroglycerin 30% (6/20), p < 0.05]. CONCLUSIONS: Intravenous nicardipine is as effective as nitroglycerin in the treatment of perioperative hypertension. Specific advantages have been identified such as stable dose-response effect, less hypotensive and tachycardial effects during the use of iv nicardipine in treatment of hypertensive patients. 相似文献
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94.
DA Lashkari JL DeRisi JH McCusker AF Namath C Gentile SY Hwang PO Brown RW Davis 《Canadian Metallurgical Quarterly》1997,94(24):13057-13062
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In order to develop an ELISA system for the antibody detection of HIV-1 or HIV-2 infections, MAPs for HIV-1 gp41(584-618) and HIV-2 gp36(574-602) corresponding to the immunodominant regions of HIV-1 gp41 and HIV-2 gp36 were used as coating antigens in the ELISA. The MAPs were synthesized by the solid phase method using Fmoc-Lys(Fmoc)-OH and their molecular weights were confirmed by tricine gel electrophoresis. The MAPs reacted with all HIV positive sera (64 samples), but did not react with HIV negative sera (48 samples) obtained from healthy blood donors. The MAPs showed high sensitivity and specificity in anti-HIV 1/2 combo panel and anti-HIV-1 seroconversion panels. The results indicated that the ELISA system using synthetic MAPs of gp41(584-618) and gp36(574-602) as coating antigens can be used as an analytical system for the immunodiagnosis of HIV-1 or HIV-2 infections. 相似文献
97.
INTRODUCTION: A costovertebral paraganglioma with a long history of recurrences and metastases is reported. MATERIAL AND METHODS: The lesion is documented on histological ground and with immunocytochemistry and electron microscopy. RESULTS: The patient is a 42 year old man which presented with a 5 cm axillary mass and enlarged mediastinal lymph nodes. The former lesion has been interpreted as a metastasis of paraganglioma. The patient underwent surgery because of a costovertebral paraganglioma at the age of 19 and showed locoregional metastases and a recurrence over a period of 23 years. Twenty-seven years from removal of the primitive tumor, the patient is alive and well. All the neoplasms showed identical histological features as they were composed of neoplastic elements arranged in nests surrounded by dendritic cells. Neoplastic cells immunoreacted with anti-chromogranin antiserum whereas sustentacolar cells were positive with S-100 antiserum. DISCUSSION: The differential diagnosis between a multicentric paraganglioma a metastasis has been particularly taken into consideration. In addition, axillary tumor was distinguished from a metastatic renal cell carcinoma and melanoma. The literature regarding costovertebral paraganglioma has been also revised. 相似文献
98.
To functionalize the surface of nanoparticles with phenyl groups for subsequent cross-linking with aromatic molecules by mutual interactions, we prepared functional nanoparticles (d = 3 nm) by silanization with phenyl-triethoxysilane. The nanoparticles had Fe(2)O(3) cores conjugated to phenyl groups; this was confirmed by Fourier transform infrared (FT-IR) spectroscopy and absorption spectrophotometry. The typical C-H and C-C peaks and the absorption at 240 nm, which corresponds to aromatic rings, were detected in the spectroscopic results for the phenyl group-modified nanoparticles. The nanoparticles could ionize aromatic (colchicine, reserpine, and bradykinin peptide) and nonaromatic (L-α-phosphatidylethanolamine,dioleoyl, and polyethylene glycol) molecules by nanoparticle-assisted laser desorption/ionization mass spectrometry. The nanoparticles worked as a selective trap and an ionization-assisting reagent in mass spectrometry for the aromatic molecular targets. 相似文献
99.
K Saoulli SY Lee JL Cannons WC Yeh A Santana MD Goldstein N Bangia MA DeBenedette TW Mak Y Choi TH Watts 《Canadian Metallurgical Quarterly》1998,187(11):1849-1862
4-1BB ligand (4-1BBL) is a member of the tumor necrosis factor (TNF) family expressed on activated antigen-presenting cells. Its receptor, 4-1BB, is a member of the TNF receptor family expressed on activated CD4 and CD8 T cells. We have produced a soluble form of 4-1BBL using the baculovirus expression system. When coimmobilized on plastic with anti-CD3, soluble 4-1BBL induces interleukin (IL)-2 production by resting CD28+ or CD28- T cells, indicating that 4-1BBL can function independently of other cell surface molecules, including CD28, in costimulation of resting T cell activation. At low concentrations of anti-CD3, 4-1BBL is inferior to anti-CD28 in T cell activation. However, when 4-1BB ligand is provided together with strong TCR signals, then 4-1BBL and anti-CD28 are equally potent in stimulation of IL-2 production by resting T cells. We find that TNF receptor-associated factor (TRAF)1 or TRAF2 associate with a glutathione S-transferase-4-1BB cytoplasmic domain fusion protein in vitro. In T cells, we find that association of TRAF1 and TRAF2 with 4-1BB requires 4-1BB cross-linking. In support of a functional role for TRAF2 in 4-1BB signaling, we find that resting T cells isolated from TRAF2-deficient mice or from mice expressing a dominant negative form of TRAF2 fail to augment IL-2 production in response to soluble 4-1BBL. Thus 4-1BB, via the TRAF2 molecule, can provide CD28-independent costimulatory signals to resting T cells. 相似文献
100.
SY Gauthier CM Kay BD Sykes VK Walker PL Davies 《Canadian Metallurgical Quarterly》1998,258(2):445-453
We have previously reported that bryostation 1 (Bryo 1) induces differentiation of chronic lymphocytic leukemia (CLL) in vitro to a hairy cell (HC) stage. This study tests the hypothesis that Bryo 1-differentiated CLL cells are more susceptible to 2-chlorodeoxyadenosine (2-CdA) than parent CLL cells. A recently established EBV-negative CLL line (WSU-CLL) from a patient resistant to chemotherapy including fludarabine was used to test this hypothesis. Both Bryo 1 (10-1000 nM) and 2-CdA (5.6-22.4 microM) exhibited a dose-dependent growth inhibitory effect on the WSU-CLL cell line. In vitro, the sequential exposure to Bryo 1 (100 nM for 72 h) followed by 2-CdA (11.2 microM) resulted in significantly higher rates of growth inhibition than either agent alone. Changes in immunophenotype, enzymes, lipids, proteins, and the DNA of WSU-CLL cells were studied before and after Bryo 1 treatment. Bryo 1 induced a positive tartrate-resistant acid phosphatase reaction and two important markers, CD11c and CD25, after 72 h of culture, confirming the differentiation of CLL to HC. The Fourier transformation infrared spectroscopic analysis showed that the amount of membrane lipids significantly increased in Bryo 1-treated cells compared to controls after 24 h, whereas the protein content, as well as the DNA content, decreased. This finding supports the change of CLL to HC. To evaluate the in vivo efficacy of Bryo 1 and 2-CdA, we used a xenograft model of CLL in WSU-CLL-bearing mice with severe combined immune deficiency. s.c. tumors were developed by injection of 10(7) WSU-CLL cells, and fragments were then transplanted into a new batch of severe combined immunodeficient mice. Bryo 1 and 2-CdA at the maximum tolerated doses (75 micrograms/kg i.p. and 30 mg/kg s.c., respectively) were administered to the mice at different combinations and schedules. The survival in days, the tumor growth inhibition ratio, the tumor growth delay, and the log10 kill of the mice treated with Bryo 1 followed by 2-CdA were significantly better than the control and other groups. We conclude that the sequential treatment with Bryo 1 followed by 2-CdA resulted in higher antitumor activity and improved animal survival. 相似文献