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101.
Some novel 6-fluoro-7-substituted-1,4-dihydro-4-oxoquinoline-3-carboxylic acids have been prepared. At the N-1 position "standard" substitution was employed with the ethyl, cyclopropyl, and p-fluorophenyl groups being used. At C-7 the introduction of some novel piperazines was made. Most notably, 2-(fluoromethyl)piperazine (10) and hexahydro-6-fluoro-1H-1,4-diazepine (16, fluorohomopiperazine) at the quinolone C-7 position produced products with similar in vitro antibacterial activity as the ciprofloxacin reference. The in vivo efficacy of 1-cyclopropyl-6-fluoro-7-[3-(fluoromethyl)piperazinyl]-1,4-dihydro-4- oxoquinoline-3-carboxylic acid (20) was excellent with better oral absorption than ciprofloxacin (2).  相似文献   
102.
Prevention of high-risk behaviors in adolescent women.   总被引:1,自引:0,他引:1  
PURPOSE: To better delineate the impact of health risk behaviors on adolescent women's current and future health and development. METHOD: The Commonwealth Fund Survey of Adolescent Health, a national survey of adolescents in Grades 5-12 designed to better understand their health and health care needs, was used as the basis for this study. Survey data were collected in 1997 from a total of 6730 adolescents (3568 females, 3162 males). Areas examined include smoking, drinking, use of other drugs, violence, safety, reproductive risks, and the prevention of risk behaviors in adolescent women. RESULTS: Adolescent women are almost equally likely to smoke, drink, and engage in other substance use as their male counterparts, but with increased health risks. Different motivations for engaging in risk behavior also are evident. Adolescent women are also more likely than adolescent men to experience physical abuse, and they are twice as likely to be sexually abused. CONCLUSIONS: Effective prevention programs need to recognize that the motivations for engaging in risk behaviors may differ by gender. Developmental awareness, proper assessment, and pivotal institutions can provide and shape what is needed for healthy development.  相似文献   
103.
Normative data were presented that defined the upper and lower standards for deciding if cognitive abilities show reliable change over 2 or more testing occasions when retesting occurs at 1- to 2-year intervals. The Mayo Cognitive Factor Scores (MCFS; G. E. Smith et al., 1994) were analyzed because they permit the quantitation of overall functioning in 5 clinically important cognitive domains: established verbal knowledge, nonverbal reasoning, attention and concentration, new learning, and delayed memory. To the authors' knowledge, this is the first report of both group-level and individual-level data analyses derived from a respectably sized sample of normal persons who have been tested 3 or more times at clinically common test-retest intervals.  相似文献   
104.
Blood supply of the tibialis anterior tendon   总被引:3,自引:1,他引:2  
Injection techniques and immunohistochemical methods (antibodies against laminin) were performed to uncover the vascular pattern of the human tibialis anterior tendon with regard to spontaneous rupture of this tendon. Proximally, the blood supply of the tibialis anterior tendon mainly arises from the anterior tibial artery. Distally, the tendon is supplied by branches of the medial tarsal artery. Blood vessels enter the peritenon via vinculae from the posterior side. From the peritenon, the blood vessels penetrate the tendon and anastomose with a longitudinally orientated intratendinous network. Compared with the surrounding peritenon, the number of vessels in the tendon substance is greatly reduced. The distribution of blood vessels within the anterior tibial tendon is not homogenous. The posterior part of the tendon has a complete vascular network that extends from the musculotendinous junction to the insertion at the bone. In the anterior half of the tendon, there is an avascular zone between 45 and 67 mm in length. The location of the avascular zone correlates well with the location of the most frequent site of spontaneous rupture of the tibialis anterior tendon reported in the literature. Hypovascularity has to be considered as an etiological cofactor for spontaneous rupture of the tibialis anterior tendon.  相似文献   
105.
PURPOSE: We clarify the impact of removal of the tumor bearing testis on semen quality and reproductive hormones in men with testicular cancer. MATERIALS AND METHODS: Semen quality and levels of reproductive hormones were investigated in 48 men before and after orchiectomy for testicular cancer. Semen analysis was done in 35 of these men and hormone analyses were done in 47. The hormone data of patients with (14) or without (33) elevated values of human chorionic gonadotropin (HCG) were analyzed separately. RESULTS: Median sperm concentration and total sperm count decreased from 17 x 10(6)/ml. (range 0 to 117) and 39 x 10(6) (0 to 433), respectively, before to 7 x 10(6)/ml. (0 to 69) and 30 x 10(6) (0 to 200), respectively, after orchiectomy. After orchiectomy sperm concentration was decreased in 30 of 35 men (p = 0.001) and azoospermia developed in 3 (9%). In men without detectable HCG median follicle-stimulating hormone levels increased (p <0.001) from 5.7 IU/l. (range 0.01 to 30) before to 10.0 IU/l. (4.6 to 48) after orchiectomy in 33 of 33 patients. Median inhibin B significantly decreased (p = 0.003) from 108 pg./l. (range 60 to 193) before to 95 pg./l. (less than 20 to 141) after orchiectomy. Median luteinizing hormone increased significantly from 3.1 IU/l. (range 1.1 to 9.9) before to 5.2 IU/l. (2.1 to 27) after treatment (p <0.001). Testosterone and sex hormone-binding globulin did not change significantly after orchiectomy. Patients with detectable serum HCG before orchiectomy had a considerable increase in follicle-stimulating hormone after orchiectomy, and a concomitant decrease in testosterone and estradiol. CONCLUSIONS: Semen quality was poor at diagnosis and deteriorated further after orchiectomy compared with pretreatment values. Our findings indicate that in some patients the most appropriate time for cryopreservation of semen is before orchiectomy. Androgen production was maintained by increased luteinizing hormone stimulation after orchiectomy.  相似文献   
106.
PURPOSE: To evaluate possible changes in aetiology and frequency of bulbar eviscerations and enucleations. METHODS: A total of 1028 cases from three two-year periods: 1975-76, 1985-86 and 1995-96 collected by the Eye Pathology Institute were reviewed. RESULTS: A significant decrease (p<0.001) in number of enucleations was observed from 358 in 1975-76 to 214 in 1995-96, corresponding to an almost equivalent increase in number of eviscerations from 5 in 1975-76 to 83 in 1995-96. The total number of eye removals decreased significantly (p<0.01) over the last two periods from 368 in 1985-86 to 296 in 1995-96. This was primarily caused by a decrease in the number of glaucoma-related enucleations from 32.7% in 1975-76 to 15.0% in 1995-96. The reduction in number was not fully balanced by the increase in glaucoma-related eviscerations. CONCLUSION: Over the last 20 years there has been a change in choice of operation from enucleation to evisceration.  相似文献   
107.
The effect of salbutamol on performance in endurance cyclists   总被引:3,自引:0,他引:3  
The effect of salbutamol (S) on cycling performance was examined in 15 highly trained non-asthmatic male cyclists. A double-blind, randomized cross-over design was used with S or placebo (P) administered using a metered-dose inhaler and a spacer device 20 min before each testing session. The S dose was 400 μg (four puffs), which is twice the normal therapeutic level. Subjects were habituated to all the laboratory procedures in the week prior to actual data collection. The subjects performed four tests under S and P conditions on separate days over 2 weeks. These included measurement of maximal O2 uptake (cycle ergometry) with assessment of pulmonary function before and after, a submaximal (90% of ventilatory threshold) square-wave work transition from a base of unloaded cycling, a 60-s modified Wingate test, and a simulated 20 km time trial. No significant differences were observed in any of the dependent variables related to aerobic endurance or cycling performance between the S and P conditions. These results support other findings that an acute dose (400 μg) of S has no performance-enhancing properties.  相似文献   
108.
Summary Pharmacokinetic analysis of epirubicin and its metabolites epirubicinol and 7-deoxy-13-dihydro-epirubicinol aglycone during the first and the fourth courses of treatment was performed in 78 patients with metastatic breast cancer. The patients were treated every 3 weeks with epirubicin given as 10-min i.v. infusions at four different dose levels: 40, 60, 90 and 135 mg/m2. In most cases (76 of 78 cases), plasma concentration-time curves fitted to a three-compartmental pharmacokinetic model. The terminal half-life of epirubicin was independent of dose and duration of treatment. Large interindividual differences were demonstrated (meant 1/2, 21.6±7.9 h; range, 10.6–69 h;n=110). In two subjects, extremely long half-lives and high serum bilirubin concentrations indicated impaired liver function. No correlation was found between the half-life and levels of liver alanine aminotransferase (ALAT) or serum creatinine. The metabolite epirubicinol appeared quickly after epirubicin administration and its half-lives were shorter than that of the parent compound (meant 1/2, 18.1±4.8 h; range, 8.2–38.4 h;n=105).Formation of the aglycone metabolite was delayed and the half-life of this metabolite was shorter than that of epirubicin (meant 1/2, 13±4.6 h; range, 2.7–29 h;n=104). The AUC of epirubicin and the total AUC (drug and metabolites) were linearly proportional to the dose, with the former value constituting two-thirds of the latter. A correlation was found between AUC and the plasma concentration of epirubicin at two time points (2 and 24 h after administration). The proposed model was AUC=9.44×c 2+62.5×c 24+157.7 (r=0.953).This work was supported by the Lundbeck Foundation, the Michaelsen Foundation and Farmitalia Carlo Erba Ltd.  相似文献   
109.
Brigham and Women's Hospital initiated a study of the quality of care centering on self-reporting of potential medical injuries by providers. The goal of the study is to decrease the incidence of such injuries through a continuous quality methodology that integrates providers into the identification phase and incorporates all hospital employees in the development of new practices. This article provides an overview of the investigation methodology and discusses the conceptual relationships between clinical epidemiological analyses and industrial quality improvement.  相似文献   
110.
Steady-state kinetics of imipramine in patients   总被引:1,自引:0,他引:1  
Steady-state plasma level kinetics were studied in 76 patients given imipramine (IP) 150 to 225 mg/day for 2–5 weeks. IP was given in three divided doses at 8.00 a.m., 1.00 p.m. and 5.00 p.m. Plasma concentrations of IP and its active metabolite desipramine (DMI) were determined by quantitative in situ thin-layer chromatography. The plasma levels of IP and DMI showed pronounced flucutations throughout the day with a ratio of about 2 between highest and lowest level. Patients with steady-state levels of IP and/or DMI below 50 g/l reached this within 1 week of treatment. Patients with higher steady-state levels reached steady-state concentrations within 2–3 weeks. There were some intraindividual fluctuations in plasma levels from week to week after steady state had been reached (coefficient of variation: 10–20%). Interindividually, the steady-state levels corrected to a dose of 3.5 mg/kg per day varied considerably: IP: 6–356 g/l, DMI: 24–659 g/l and IP+DMI: 58–809 g/l. The steady-state plasma levels showed a skew distribution that became normal by logarithmic transformation. The IP/DMI ratio ranged from 0.07 to 5.5 with a median value of 0.47. Compared to data from amitriptyline treated patients the IP/DMI ratios had significantly lower median value and larger variation than the corresponding plasma level ratios of amitriptyline/nortriptyline. Several statistically significant differences in steady-state levels between age groups were found. For IP: Women aged 30–39 had lower levels than women aged 20–29, 40–49, and 50–59, and men aged 50–59 and 60–65; men aged 30–39 had lower levels than men aged 60–65. For DMI: Women aged 30–39 had lower levels than women aged 50–59.  相似文献   
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