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61.
A mathematical multiple dosing model was designed so that human plasma concentration-versus-time curves of beta-lactams are reproduced in mouse plasma. The pharmacokinetic parameters of FK037, a new injective cephalosporin, in volunteers and in the mice model were 6,966 and 6,894 ml, respectively, for Vc, 2.592 and 2.698/h for alpha, 0.2875 and 0.3027/h for beta, and 0.9079 and 1.0506 for K21. Therefore, real pharmacokinetics of humans were reproduced in mice by this method. The 8-hour therapeutic efficacy (the decrease of the viable counts in the lung) against pneumonia with Staphylococcus aureus and Pseudomonas aeruginosa in mice was well correlated with the time above MIC value, but not with AUC, Cmax or AUC above MIC. These results indicate that this model was valuable to evaluate the beta-lactam antibiotics for predicting their clinical efficacy and that the time above MIC is an important factor in selecting beta-lactam agents and determining dosage in pulmonary infection. 相似文献
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VN Vecherko PP Konoplia FA Gredzhev AD Zubov NV Momot 《Canadian Metallurgical Quarterly》1995,154(3):42-44
Under analysis is an experience with examining and treatment of 167 patients with focal lesions of the liver using computed tomography. Percutaneous transhepatic puncture and draining the hepatic abscesses and cysts under control of computed tomography is an independent method of treatment used in 53 patients. The technique of performing the puncture and drainage is described. Specific features of surgical treatment of focal lesions of the liver are described. Decompression of bile ducts in the postoperative period is shown to be necessary. A conclusion is made about high efficiency of computed tomography in diagnosis and treatment of focal lesions of the liver. 相似文献
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We report a case of a 63-year-old woman who presented with pseudoaneurysm of the free wall of the left ventricle secondary to myocardial infarction, in the presence of angiographically normal major coronary arteries. This is the only such case we know of, in which the patient underwent successful surgical correction. At last follow-up, the patient was in good condition with no evidence of cardiac disease, at 9 years after surgery. 相似文献
64.
PG Tarazov VK Ryzhkov VN Polysalov KV Prozorovski? AA Polikarpov 《Canadian Metallurgical Quarterly》1998,11(1):55-9; discussion 59-60
BACKGROUND: We evaluated the safety and efficacy of transurethral electrovaporization of the prostate (TVP) as a new alternative treatment for patients with benign prostatic hyperplasia. METHODS: A total of 22 patients with symptomatic benign prostatic hyperplasia, including 4 with urinary retention, underwent TVP. If enough of a cavity was not created after 60 minutes of vaporization, transurethral resection of the prostate (TURP) was performed successively. International Prostate Symptom Score (I-PSS) with quality-of-life index, maximum flow rate, and postvoid residual volume were measured at baseline and at 2 weeks, 1, 3, and 6 months. A pressure-flow study was performed at baseline and at 3 or 6 months after surgery. RESULTS: TURP was required in 10 of 22 patients. At 6 months, mean I-PSS decreased from 20.0 to 5.2, quality-of-life index decreased from 4.6 to 1.1, mean maximum flow rate increased from 6.9 to 16.7 mL/s, and postvoid residual volume decreased from 152 to 32 mL. Detrusor pressure at maximum flow decreased from 108 to 39 cm H2O, with a significant relief of bladder outlet obstruction in 93% of the patients. Mean decrease in hematocrit was 4.4%, and in serum sodium, 4.8 mEq/L. None of the patients required transfusions or had TUR syndrome. A urethral stricture and a severe stress incontinence developed in 1 patient. CONCLUSION: TVP seems to be a safe and effective alternative to a standard TURP associated with fewer intraoperative complications. Although preliminary clinical results have been promising, further study is necessary to establish long-term efficacy and safety of this procedure. 相似文献
65.
VN Malashkevich DC Chan CT Chutkowski PS Kim 《Canadian Metallurgical Quarterly》1998,95(16):9134-9139
The gp41 subunit of the envelope protein complex from human and simian immunodeficiency viruses (HIV and SIV) mediates membrane fusion during viral entry. The crystal structure of the HIV-1 gp41 ectodomain core in its proposed fusion-active state is a six-helix bundle. Here we have reconstituted the core of the SIV gp41 ectodomain with two synthetic peptides called SIV N36 and SIV C34, which form a highly helical trimer of heterodimers. The 2.2 A resolution crystal structure of this SIV N36/C34 complex is very similar to the analogous structure in HIV-1 gp41. In both structures, three N36 helices form a central trimeric coiled coil. Three C34 helices pack in an antiparallel orientation into highly conserved, hydrophobic grooves along the surface of this coiled coil. The conserved nature of the N36-C34 interface suggests that the HIV-1 and SIV peptides are functionally interchangeable. Indeed, a heterotypic complex between HIV-1 N36 and SIV C34 peptides is highly helical and stable. Moreover, as with HIV-1 C34, the SIV C34 peptide is a potent inhibitor of HIV-1 infection. These results identify conserved packing interactions between the N and C helices of gp41 and have implications for the development of C peptide analogs with broad inhibitory activity. 相似文献
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MF Chan A Kois EJ Verner BG Raju RS Castillo C Wu I Okun FD Stavros VN Balaji 《Canadian Metallurgical Quarterly》1998,6(12):2301-2316
The systematic modification of the ETA selective N-(5-isoxazolyl)benzene-sulfonamide endothelin antagonists to give ETB selective antagonists is reported. The reversal in selectivity was brought about by substitution of the 4-position with aryl and substituted aryl groups. Of all the aromatic substituents studied, the para-tolyl group gave rise to the most active and selective ETB antagonist. Larger substituents caused a decrease in both ETB activity and selectivity. A similar trend was observed by substitution at the 5-position of the N-(5-isoxazolyl)-2-thiophenesulfonamide ETA receptor antagonists. The para-tolyl group was again found to be optimal for the ETB activity and selectivity. The structural features that were found to be favorable for binding to the ETB receptor, that is, the presence of a linear, conjugated pi-system of definite shape and size, have been successfully incorporated into the design of ETB selective polycyclic aromatic sulfonamides antagonists. 相似文献
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