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991.
In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed.  相似文献   
992.
Mechanical properties of post and core systems   总被引:1,自引:0,他引:1  
  相似文献   
993.
994.
Of 299 patients who presented with superficial bladder cancer (Ta, T1), 60 were treated by intravesical chemotherapy (Epodyl, methotrexate or mitomycin C). The rate of tumour progression to muscle invasion or metastases was identical for each intravesical regime. There was no evidence that mitomycin C promoted tumour progression. Carcinoma in situ in non-tumour-bearing urothelium was the most significant predictive factor for progression to muscle invasion or metastases.  相似文献   
995.
Five studies were conducted to examine the degree of variability to be expected during the use of the non-imaging nuclear probe (BIOS Inc.) under a variety of clinical conditions. Comparison of the ejection fraction (EF) readings between the nuclear probe and a gamma camera showed good agreement, with the nuclear probe tending to underestimate lower, and overestimate higher camera EF values [mean (S.D.) difference, 0.84% (6.06)]. A comparison of two nuclear probes showed a small mean (S.D.) difference of EF readings of 0.063% (2.26). EF readings obtained in normal subjects 6 weeks apart were reproducible and differed by a mean (S.D.) of 0.23% (4.42). The administration of placebo to 10 normal subjects followed by sequential measurements for 4 h produced EF changes large enough to mimic a clinical effect, the largest hourly change observed being 5.4%, indicating the need for strict placebo control in interventional experiments. Data on four patients with heart failure showed small non-significant EF changes in the 1 h after placebo administration but a wide intra-subject range of ejection time and time to peak filling measurements. This highlights the problem of accurate, reproducible cursor placement in such patients. The nuclear probe is a portable, low cost instrument which produces accurate EF measurements when compared with the gamma camera.  相似文献   
996.
Bilateral simultaneous Achilles tendon ruptures are rare, with only ten cases reported in the English literature. Our case is that of a 44-year-old woman, along with a review of the literature. Affected persons usually are on chronic steroid treatment and in the fifth to seventh decades of life. The patient may have concomitant systemic disease, and the injury occurs with relatively mild trauma. The goals of treatment are mainly preventative, i.e., cessation of steroids as soon as possible and protective bracing of the remaining intact Achilles tendon.  相似文献   
997.
Pepsinogen II (PG II) is a gastric proenzyme which has previously been found in both human seminal fluid and the prostate gland. However, no regional distribution of PG II has been noted within the prostate nor has it been found in the seminal vesicle. Bouins-fixed sections of central zone, peripheral zone and seminal vesicle, taken from 10 prostates removed at radical prostatectomy or cystectomy, were exposed to antibody against PG II and stained using the A-B-C immunoperoxidase technique. Formalin-fixed tissue from autopsy prostates of four men in the third decade, and six cases with BPH nodules, were also examined for PG II activity. In nine of 10 seminal vesicles, and seven of 10 central zone samples, more than 50 per cent of the cells stained positive for PG II. By contrast, in nine of 10 peripheral zone samples staining was present in five per cent or less of the epithelial cells. Similarly, PG II activity in the four autopsy prostates occurred almost entirely within the central zone and ended abruptly at the boundary between the peripheral and central zones. BPH nodules contained no PG II activity. These findings provide the first evidence that the central and peripheral zones may serve different biological functions. Embryologically it is currently thought that the prostate is of endodermal origin and the seminal vesicle of mesodermal origin. The presence of large amounts of PG II in both the seminal vesicle and central zone lends support to the hypothesis of a common mesodermal origin for these two structures.  相似文献   
998.
The clinical and serological findings and computer tomographic (CT) appearances of a case of secondary cerebral amebiasis due to Entamoeba histolytica are presented. The effect of therapy on the neurological symptoms as well as on the CT findings are described in detail. The multiple intracerebral lesions resolved almost completely and the patient survived without any neurological sequelae.  相似文献   
999.
It is commonly accepted that there are physiological and morphological gender differences. These differences become evident in the specific responses or magnitude of response to various training regimens. Very little difference is seen in the response to different modes of progressive resistance strength training. Men and women experience similar relative strength gains when training under the same programme. The evidence on body composition changes that occur with strength training is equivocal at this point. Researchers, however, suggest that there appears to be less muscle hypertrophy with strength improvement in women when compared to men. The data suggest that there are no differences between genders in central or peripheral cardiovascular adaptations to aerobic training. However, women in general have a reduced O2 carrying capacity. Another factor that may be responsible for the sex differences seen in the metabolic responses to exercise may be the greater, essential sex specific fat of women. Sparling and Cureton (1983) have shown that differences in similarly trained male and female distance runners are due largely to percentage body fat, less to cardiorespiratory fitness and least to running economy. Pate et al. (1985) determined that men and women who are capable of similar performances, in this case a 15 mile race, do not differ in body composition, cardiorespiratory response or metabolic response. There appear to be no differences in relative increases in VO2max for men and women when they are trained under the same intensity, frequency and duration. Mode of training also appears to elicit no sex difference. Hormonal factors lead to greater initial levels of high density lipoproteins in women. This appears to cause a smaller change in the total cholesterol-high density lipoprotein ratio than occurs with aerobic training in men. Generally, the menstrual cycle phase makes no difference to performance in women. The special cases of exercise in hot and cold environments present conflicting evidence. When men and women are matched for surface area:mass, VO2max and percentage body fat, the major disadvantages women have in the heat disappear. The question of gender differences in the cold has yet to be fully explored. When the general population is compared, men appear to have an advantage over women.  相似文献   
1000.
Pseudomonas aeruginosa ribosomal vaccines were tested for their ability to protect rats subjected to a 20% total body surface burn against the lethal effects of infection with homologous organisms. When administered prior to burning, the vaccines provided 100% protection. When administered postburning, the vaccine from one strain also provided 100% protection when the time interval between vaccination and infection was 3 days. When this time interval was reduced to 1 or 2 days, approximately 50% protection was obtained with the same vaccine. The vaccine from a second strain tested provided about 50% protection with a 3-day time interval. In addition, passive immunization using antiserum to a ribosomal vaccine was also demonstrated to be effective in protecting burned and infected rats, especially when multiple doses of antiserum were used. In this case, 80% protection was obtained (with no protection observed using multiple doses of normal serum). Finally, a comparison of ribosomal and lipopolysaccharide vaccines and antisera was also performed.  相似文献   
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