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71.
72.
Responses of rat isolated vas deferens to electrical stimulation through field electrodes (400 mA, 1 ms duration, single shocks at 5 min intervals) were potentiated by meptazinol (10 to 300 microM) in whole tissues and also in the separated prostatic and epididymal portions. The effect was fast in onset, reproducible and easily reversed by washing. Prazosin (0.1 microM) practically abolished the response of the epididymal portion to electrical stimulation while the response of the prostatic portion was only slightly reduced (less than 20%). In the presence of prazosin, meptazinol still produced potentiation of the response of the prostatic portion. Nifedipine (2 microM) practically abolished the response of the prostatic portion to electrical stimulation while the response of the epididymal portion was only slightly reduced (less than 20%). In the presence of nifedipine, meptazinol no longer produced potentiation of the response of the epididymal portion. Exogenous ATP (5 microM to 1 mM) and phenylephrine (1 to 50 microM) produced a contractile response which was potentiated in the presence of meptazinol (100 microM) but in the presence of meptazinol (100 microM) and nifedipine (5 mM) together, potentiation of phenylephrine no longer occurred. It is suggested that potentiation by meptazinol of electrically induced responses in this tissue is due to a direct action on the smooth muscle.  相似文献   
73.
Prevalence of tobacco dependence and withdrawal   总被引:3,自引:0,他引:3  
In a sample of 1,006 middle-aged male smokers drawn from the general population, 90% (N = 905) fulfilled DSM-III criteria and 36% (N = 362) fulfilled Fagerstrom's criteria for tobacco dependence. Among the 875 who had stopped smoking in the past for at least 24 hours, 21% (N = 184) fulfilled DSM-III criteria and 46% (N = 403) fulfilled the authors' own criteria for tobacco withdrawal. Concordance of results among the criteria for diagnosing tobacco dependence and withdrawal was low. These results suggest that the DSM-III criteria for tobacco dependence are overinclusive and that there is little consensus among the definitions of tobacco dependence and withdrawal.  相似文献   
74.
75.
Antibiotic therapy of pleural empyema.   总被引:1,自引:0,他引:1  
Most empyemas occur as a complication of pneumonia or lung abscess, but 15% to 30% occur after thoracic surgery and 10% occur in association with an intraabdominal infection. The bacteriology of empyemas that occur in association with lung infections is often polymicrobial and mixed, containing multiple species of both aerobic and anaerobic bacteria, the latter found in up to 75% of cases. In contrast, empyema following thoracic surgery is more likely to be monomicrobial and caused by common nosocomial pathogens such as Staphylococcus aureus and aerobic gram-negative bacilli. Diffusion of antibiotics into both infected and uninfected pleural fluid is good, but certain agents (aminoglycosides and some beta-lactams) may be inactivated in the presence of pus, low pH, and beta-lactamase enzymes. Single antibiotic agents that are likely to be active against the wide spectrum of potential pathogens include imipenem-cilastatin and ticarcillin-clavulanic acid. Combinations of antibiotics should include an effective agent against anaerobic bacteria (clindamycin, metronidazole) coupled with an agent active against aerobic gram-positive cocci and gram-negative bacilli.  相似文献   
76.
In the pursuit of gains in muscle size and strength, body-builders may mistakenly use illicit drugs believing them to be anabolic steroids. The case described illustrates the physical and psychological dangers of such behaviour.  相似文献   
77.
Interleukin-6: effects on and production by rat granulosa cells in vitro.   总被引:5,自引:0,他引:5  
Treatment of FSH-stimulated granulosa cells with increasing amounts of interleukin-6 (IL-6) caused a significant concentration-dependent suppression of progesterone biosynthesis. However, basal progesterone production in non-FSH-stimulated cells remained unresponsive to the cytokine. Quantitation of IL-6 in the conditioned media from untreated granulosa cells by the 7TD1 hybridoma cell bioassay revealed detectable levels of IL-6. Further, FSH treatment caused a significant concentration-dependent increase in IL-6 release. In contrast, both basal and FSH-stimulated IL-6 release could be significantly suppressed by interferon gamma (INF-gamma). The results of the present study suggest: 1) a role for IL-6 in the regulation of progesterone production, 2) that the granulosa cell is a source of IL-6 and 3) that the release of IL-6 by the granulosa cell is a regulated event.  相似文献   
78.
Alternative treatments such as troleandomycin methotrexate, gold, and intravenous gamma globulin are sometimes considered for severe asthmatics to minimize the need for systemic corticosteroids and reduce adverse effects. These alternative therapies may also be associated with significant toxicity and expense. The ability to reduce corticosteroid use and the need for alternative treatment interventions in 125 pediatric patients at our institution were reviewed. Because corticosteroid requirements were reduced significantly, only 23 of 125 children evaluated were considered for treatment alternatives with only 10 receiving such therapy. This study emphasizes the importance of a thorough and comprehensive review of corticosteroid requirements and usage prior to initiating alternative approaches to treatment in moderate to severe asthmatics as well as in patients thought to be “steroid-dependent.”  相似文献   
79.
To determine the utility of the lateral view of the chest in emergency department patients, records of all patients who had had 2-view chest x-rays ordered in the emergency department were reviewed retrospectively. A study radiologist recorded a reading of the posteroanterior (PA) radiograph alone. The lateral radiograph was then provided, along with the PA view, and a second reading was recorded. A comparison was then made between the first and second readings.A total of 417 sets of x-rays were included. The PA view alone successfully diagnosed or suspected 92% of pulmonary nodules, 95% of effusions, 97% of cases of emphysema, 98% of pneumonias, and 100% of cases of cardiomegaly, pulmonary edema, interstitial pulmonary disease, and atelectasis.In the emergency department patient population, lateral views of the chest have minimal diagnostic yield and therefore may be used selectively to safely decrease the amount of breast radiation exposure to young women.  相似文献   
80.
The present conventional methods for determination of Hemoglobin (Hb) concentration in whole blood depend on the direct colorimetric measurement of chemically modified Hb following its release from red cells by lysis. This paper examines an alternative, indirect method which does not require initial red cell lysis, corrects for the falsely elevated Hb due to the lipemic plasma and determines whether elevated WBC count effects a change in the Hb value, without the tedious laboratory manipulations currently required to correct for these artifacts. The method is simple, uncomplicated and is based on the observation of a constant ratio (2.98) between the Mean Corpuscular Volume (MCV) and the Mean Corpuscular Hemoglobin (MCH) indices obtained from standard electronic counters in use in most laboratories. The Hb concentration is calculated by the equation: [formula: see text]. The resultant Hb measurements show an acceptable degree of accuracy and precision when compared with the direct measurements obtained from a Coulter Model S + I, even in the presence of a high WBC or lipid.  相似文献   
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