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71.
Franklin G. King Robert L. Dedrick 《Journal of pharmacokinetics and pharmacodynamics》1981,9(5):519-534
A flow-limited physiologic mathematical model has been developed to describe the time course of 2deoxycoformycin (2dCF) concentrations in the plasma and tissues of mice following iv and ip doses. Urinary excretion is modeled as a linear process involving filtration and secretion, since kidney clearance exceeded estimated glomerular filtration rate. Intracellular binding is described as the sum of linear nonspecific binding plus strong saturable binding to adenosine deaminase. Pharmacokinetic parameters are determined by a sequential optimization scheme in which each tissue is studied by means of a hybrid model. The model has been used to predict pharmacokinetic behaviour of 2dCF in both normal and leukemic mice, and model simulations are compared with published data. 相似文献
72.
The use of microvascular techniques in the replantation of one partially amputated penis is presented. The advantages of these techniques are discussed. A review of the literature is included; penis-replantation results prior to the introduction of microvascular techniques are compared to results achieved since the advent of these techniques. The superior results associated with microsurgical techniques are demonstrated, and it is concluded that microsurgical replantation is the procedure of choice in the repair of penis amputations. 相似文献
73.
Sui Wang Dylan P Hartley Suzanne L Ciccotto Stella H Vincent Ronald B Franklin Mi-Sook Kim 《Drug metabolism and disposition》2003,31(6):773-775
The purpose of the present study was to evaluate the effect of 1,7-phenanthroline (PH), which has been proposed to be a selective phase II enzyme inducer, on the gene expression of xenobiotic transporters, as well as hepatic and renal drug-metabolizing enzymes. After oral administration of PH for 3 days to male Sprague-Dawley rats, mRNA levels in liver (75 and 150 mg/kg doses) and kidney (75 mg/kg dose only) were determined using real-time quantitative polymerase chain reaction. At 150 mg/kg/day, PH treatment resulted in significant increases in hepatic mRNA levels of Mrp3 (36-fold), UGT1A6 (20-fold), UGT2B1 (4-fold), and quinone reductase (QR, 5-fold), compared with the vehicle-treated group. Similar increases in Mrp3 (99-fold), UGT1A6 (17-fold), UGT2B1 (3-fold), and QR (11-fold) mRNA levels were observed in the liver after PH treatment of rats at 75 mg/kg/day. In contrast, the expression levels of CYP2C11 and Oatp2 were decreased by approximately 80 and 50%, respectively. In addition, PH (75 mg/kg/day) elicited statistically significant changes in renal gene expression of CYP3A1, UGT1A6, QR, and Mrp3, but the magnitude of renal Mrp3 induction was less than 2-fold over control. Although PH is known to modulate hepatic glucuronidation in vivo, these data indicated that PH induced mRNA levels of the efflux transporter, Mrp3, which may also affect the disposition of xenobiotics. 相似文献
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77.
Sheila A Prindiville Tim Byers Fred R Hirsch Wilbur A Franklin York E Miller Kieu O Vu Holly J Wolf Anna E Barón Kenneth R Shroyer Chan Zeng Tim C Kennedy Paul A Bunn 《Cancer epidemiology, biomarkers & prevention》2003,12(10):987-993
Individuals with cytological atypia in sputum may be at increased risk for lung cancer. We conducted a longitudinal analysis of the association between lung cancer incidence and cytological atypia in sputum samples collected prospectively from an ongoing cohort of adults at high risk for lung cancer. Cohort members had a smoking history of > or = 30 pack-years and chronic obstructive pulmonary disease documented by pulmonary airflow testing. Sputum samples collected at baseline and periodically thereafter were examined by standard cytological methods. From the cohort of 2,006 people, there were 83 incident lung cancers over 4,469 person-years of observation. At baseline, the association between personal and behavioral characteristics, and sputum cytological atypia was assessed by multiple logistic regression. The association between sputum cytological atypia and incident lung cancer was then assessed by hazard ratios using proportional hazards regression analysis, adjusting for potential confounding factors. Cytological atypia graded as moderate or worse was associated with continuing cigarette smoking (adjusted odds ratio, 2.5; 95% confidence interval, 1.5-4.1), and with lower levels of intake of fruits and vegetables (P for trend = 0.04). Atypia was not associated with several other factors, including the degree of airflow obstruction, the use of vitamin supplements, nonsteroidal anti-inflammatory drugs, or metered-dose steroid inhalers. Incident lung cancer was increased among those with moderate or worse cytological atypia (adjusted hazards ratio, 2.8; 95% confidence interval, 1.4-5.5). This association was not confounded by other risk factors. We conclude that in this high-risk cohort, cytological atypia is associated with continuing smoking and low intake of fruits and vegetables, but that independent of these and other factors, the risk of incident lung cancer is increased among those with moderate or worse grades of cytological atypia in their sputum. 相似文献
78.
William H. Lippy John M. Burkey Arnold G. Schuring Franklin M. Rizer 《The Laryngoscope》1997,107(7):919-922
Controversy exists concerning stapedectomy for patients with small air-bone gaps. The purpose of this study was to examine the results for patients who had a stapedectomy to correct a small (10 dB or less) air-bone gap. One hundred fifty-four patients with suspected otosclerosis were explored and a stapedectomy was performed in 136 (88.3%) of these cases. The mean pure-tone average (PTA) improved 16.7 dB and overclosed the preoperative bone conduction PTA by 8.1 dB. The majority of the stapedectomy patients (89.7%) had a PTA closure greater than or equal to 0 dB. These results showed that stapedectomy can be an effective procedure for eliminating and overclosing even small air-bone gaps due to otosclerosis. 相似文献
79.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
80.
Steinar Aamdal Uta Bruntsch Jean Kerger Jaap Verweij Wim Bokkel Huinink Jantien Wanders Ram Rastogi Hillary R. Franklin Stan B. Kaye 《Cancer chemotherapy and pharmacology》1997,40(5):439-443
The antitumor activity of zeniplatin, a third-generation, water-soluble platinum compound that has shown broad preclinical
antitumor activity and no significant nephrotoxicity in phase I trials, was tested in patients with advanced malignant melanoma
and advanced renal cancer. Patients who had not previously been treated, except with local limb perfusion and immunotherapy,
were given zeniplatin as bolus injections at 125 mg/m2 every 3 weeks. The main hematological toxicity was leukopenia (7/30 patients, WHO grade ≥ 3) and the main nonhematological
toxicity was nausea and vomiting (21/30 patients, WHO grade ≥ 2). Serious nephrotoxicity was observed early in the renal cancer
study and, later, also in the melanoma study. Hyperhydration did not prevent the nephrotoxicity, and the studies were stopped
after 6 renal cancer patients and 24 malignant melanoma patients had been included. Zeniplatin gave objective responses in
3 of the 21 evaluable malignant melanoma patients [2 complete responses (CRs) in patients with lymph-node metastases lasted
5 and 14 months, respectively; 1 partial response (PR) in a patient with lymph-node and liver metastases lasted 6 months].
In the renal cancer study, only four patients were evaluable for response and none responded. The results show that zeniplatin
has some activity (14%) in patients with advanced malignant melanoma, but no conclusion can be drawn regarding the activity
of zeniplatin in renal cancer as the number of patients was too low. The main toxicities were leukopenia and nausea and vomiting.
Unexpected and serious nephrotoxicity was observed, and for this reason the studies were terminated before the planned number
of patients had been included. A possible explanation for the nephrotoxicity may be drug interactions, but no firm conclusion
can yet be drawn.
Received: 16 March 1996 / Accepted: 25 March 1997 相似文献