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991.
We conducted a double-blind, randomized, placebo-controlled study to investigate the effectiveness of P6 acupuncture on postoperative vomiting in children undergoing strabismus surgery. Acupuncture was performed by laser stimulation with a low-level laser. Laser stimulation of P6 was administered 15 min before induction of anaesthesia and 15 min after arriving in the recovery room. In the laser stimulation group, the incidence of vomiting was significantly lower (25%) than that in the placebo group (85%).  相似文献   
992.
A 61-year-old women receiving warfarin after mitral valve replacement experienced extensive ecchymoses after starting tramadol therapy. Laboratory values revealed critical elevations of prothrombin time and international normalized ratio. The patient's coagulation values returned to acceptable levels after discontinuing tramadol and temporarily stopping warfarin. The mechanism for this interaction is unknown. Practitioners should be aware of the possibility of such a interaction and exercise caution when tramadol is prescribed for a patient receiving warfarin.  相似文献   
993.
994.
One hundred seven freshman student athletes in 17 different women's and men's intercollegiate sports were required to attend evening study sessions. The student athletes completed academic assignments and studied for tests primarily in cooperative learning groups. As gauges of the program's impact on the participants, 3 questionnaires were administered to a sample of 50 (25 women and 25 men). The respondents reported that (a) they worked cooperatively on academic assignments, (b) the program staff provided both academic and personal support while structuring and facilitating cooperative learning groups, and (c) they themselves were highly task oriented, confident of their academic ability, and involved in positive and supportive relationships with their fellow participants.  相似文献   
995.
Conceptuses from several mammalian species prior to implantation secrete proteins belonging to the family of interferons. The main species of interferons known to be secreted by the pig blastocyst is interferon gamma (IFNgamma), the precise role of which is unclear. We decided to explore its effects on corpus luteum (CL) function using the novel microdialysis technique in vivo. Six cycling miniature pigs were monitored for estrus by daily plasma progesterone analysis and visual symptoms. On day nine of the cycle (day zero being the day of ovulation) the animals underwent surgery, and microdialysis tubing (vitafiber, Amicon U.S.A, cut off mol. wt. 1 million) were implanted in 17 corpora lutea. The inlets and outlets of all tubings were exteriorized and the entry and exit points of tubings in the CLs sealed with tissue glue. The afferent extension tubings were connected to a fraction collector and the system was continuously flushed with Ringer at a flow rate of 2.4 ml/h. After an initial flushout phase of 8 h, fractions were collected every half hour over 3 days. On days 10, 11 and 12 post estrus 12 CLs were stimulated for 4 h with 10(-7) M, 2 x 10(7) M and 4 x 10(-7) M human recombinant IFNgamma (Pharma Biotechnologie) respectively. Simultaneously, fractions were also collected from the remaining five unstimulated corpora lutea which served as controls. Progesterone concentrations in the dialysates were estimated by a sensitive enzymeimmunoassay (EIA). A significant increase (P < 0.01) in progesterone release was observed in all 3 days following stimulation. The progesterone increase was more marked on the first day of stimulation (1 x 10[-7] M) with the hormone levels rising further even after the end of stimulation. The overall increase in progesterone concentration was 2-fold on day 10 in comparison to 15-30% on subsequent days even though IFN concentrations for stimulation were 2- and 4-fold higher. In the unstimulated CLs, a gradual decline (P < 0.01) in progesterone levels were observed over days. In conclusion, these data provide evidence that the early conceptus signals its presence by way of IFNgamma to maintain the CL in pigs.  相似文献   
996.
OBJECTIVE: To investigate the association of polyarthritis and chromosome 22q11.2 deletions. METHODS: Eighty patients with chromosome 22q11.2 deletion syndrome followed up at The Children's Hospital of Philadelphia were examined for evidence of arthropathy or arthritis. Patients with chromosome 22q11.2 deletion syndrome and polyarthritis underwent laboratory evaluations of immunologic function to determine the relationship of their immunodeficiency to the polyarthritis. RESULTS: The prevalence of polyarthritis in patients with chromosome 22q11.2 deletion syndrome was markedly increased over the prevalence of polyarticular juvenile rheumatoid arthritis (JRA) in the general population. All 3 patients with polyarthritis had evidence of impaired T cell function. Two of the patients with polyarthritis also had IgA deficiency. CONCLUSION: The chromosome 22q11.2 deletion syndrome represents a primary T cell disorder which can be associated with a JRA-like polyarthritis. All 3 patients with polyarthritis had evidence of more extensive immunoregulatory derangements than those typically seen in patients with chromosome 22q11.2 deletion, and these derangements may have predisposed to the development of polyarthritis.  相似文献   
997.
The short-term tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol), were compared with that to amalgam using a previously devised experimental model. In 24 premolar teeth of beagle dogs (47 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periradicular lesions. On each root, an apicoectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 2 weeks (23 roots) and 1 week (24 roots); they were then prepared for histological examination. The tissue response to amalgam fillings after 2 weeks and 1 week was marked by moderate or severe inflammation on all roots, and extended to < or = 0.5 mm or > 0.5 mm in 15 out of 16 roots. In contrast, after 2 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation, while the tissue response to Vitrebond was the best of the three materials, and was also the least extensive. After 1 week, the overall best tissue response was with Vitrebond, followed by Kalzinol. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were not statistically significant (P < 0.02). However, the differences between materials for both time periods with no inflammation or inflammation extending < 0.2 mm when compared with that with inflammation extending > 0.2 mm (< or = 0.5 mm or > 0.5 mm) were statistically significant (P < 0.01). Apart from amalgam, in which healing was marked by the persistence of a localized focus of inflammation adjacent to the root-end filling, even though there were intersample variations, there was little overall difference in the temporal and qualitative healing response to Vitrebond and Kalzinol. Both Vitrebond and Kalzinol have potential as root-end filling materials, as the tissue response was considerably more favourable than that to amalgam even in the short-term.  相似文献   
998.
BACKGROUND: The authors report observed 10-year brachytherapy results in the treatment of 152 consecutive patients with clinically organ-confined prostate carcinoma. METHODS: One hundred and fifty-two consecutive patients with T1-T3, low to high Gleason grade, prostate carcinoma were treated between January 1987 and June 1988 at Northwest Hospital in Seattle, Washington. Their median age was 70 years (range, 53-92 years). Of these 152 patients, 98 (64%) received an iodine-125 implant alone (Group 1), and the remaining 54 patients (36%), who were judged to have a higher risk of extraprostatic extension, also were treated with 45 gray (Gy) of external beam irradiation to the pelvis (Group 2). No patient underwent lymph node sampling, and none received androgen ablation therapy. Multivariate regression and the Mann-Whitney rank sum test were used for statistical analysis. Preoperative patient data with associated success or failure outcomes at 10 years after treatment were used for training and validating a back-propagation neural network prediction program. RESULTS: The average preoperative prostate specific antigen (PSA) value, clinical stage, and Gleason grade were 11.0 ng/mL, T2, and 5, respectively. The median posttreatment follow-up was 119 months (range, 3-134 months). Overall survival 10 years after treatment was 65%. At last follow-up only 3 of the 152 patients (2%) had died of prostate carcinoma. Ninety-seven patients (64%) remained clinically and biochemically free of disease at 10 years of follow-up and had an average PSA value of 0.18 ng/mL (range, 0.01-0.5 ng/mL). In these patients a period of 42 months was required to reach the average PSA (0.5 ng/mL). The median to last PSA follow-up was 95 months (range, 3-134 months). Postoperative needle biopsies were negative in 56% of patients, positive in 15% of patients, and not available in 29% of patients. Only 6% of patients developed bone metastasis. At 10 years there was no statistically significant difference in treatment outcome between patients who received iodine-125 alone, and those who received iodine-125 with 45-Gy external beam irradiation (P = 0.08). Nevertheless, in these two groups preoperative PSA, stage, and Gleason grade were significantly different (P < 0.01). In the artificial neural network analysis, pretreatment serum PSA was the most accurate predictor of disease-free survival. CONCLUSIONS: Percutaneous prostate brachytherapy is a valid and efficient option for treating patients with clinically organ-confined, low to high Gleason grade, prostate carcinoma. Observed 10-year follow-up documents serum PSA levels superior to those reported in several published external beam irradiation series, and comparable to those published in a number of published radical prostatectomy series.  相似文献   
999.
Newcastle disease virus [NDV (avian paramyxovirus type 1 [APMV1])] isolates were recovered from imported exotic birds confiscated following importation into the United States, from waterbirds in the United States, and from poultry. The exotic birds probably originated from Central and South America, Asia, and Africa. The NDV isolates were initially characterized as highly virulent because of a short mean death time in embryonated chicken eggs. The isolates were typed as neurotropic or viscerotropic velogenic by intracloacal inoculation of adult chickens. Intracerebral pathogenicity index values for the virulent NDV isolates ranged from 1.54 to 1.90, compared to a possible maximum value of 2.0. These isolates had a dibasic amino acid motif in the fusion protein cleavage site sequence required for host systemic replication. Sequence differences were detected surrounding the fusion protein cleavage site and the matrix protein nuclear localization signal, indicating evolution of highly virulent NDV. Phylogenetically, these isolates were categorized with other highly virulent NDV strains that caused outbreaks in southern California poultry during 1972 and in cormorants in the north central United States and southern Canada during 1990 and 1992. These isolates are related to NDV that may have the APMV1 strain chicken/Australia/AV/32 or a related virus as a possible progenitor. Recent virulent NDV isolates and those recovered during disease outbreaks since the 1970s are phylogenetically distinct from current vaccine viruses and standard challenge strains.  相似文献   
1000.
The purpose of this study was to determine how chronic exertional fatigue and sleep deprivation coupled with negative energy balance affect thermoregulation during cold exposure. Eight men wearing only shorts and socks sat quietly during 4-h cold air exposure (10 degreesC) immediately after (<2 h, A) they completed 61 days of strenuous military training (energy expenditure approximately 4,150 kcal/day, energy intake approximately 3,300 kcal/day, sleep approximately 4 h/day) and again after short (48 h, SR) and long (109 days, LR) recovery. Body weight decreased 7.4 kg from before training to A, then increased 6.4 kg by SR, with an additional 6.4 kg increase by LR. Body fat averaged 12% during A and SR and increased to 21% during LR. Rectal temperature (Tre) was lower before and during cold air exposure for A than for SR and LR. Tre declined during cold exposure in A and SR but not LR. Mean weighted skin temperature (Tsk) during cold exposure was higher in A and SR than in LR. Metabolic rate increased during all cold exposures, but it was lower during A and LR than SR. The mean body temperature (0.67 Tre + 0.33 Tsk) threshold for increasing metabolism was lower during A than SR and LR. Thus chronic exertional fatigue and sleep loss, combined with underfeeding, reduced tissue insulation and blunted metabolic heat production, which compromised maintenance of body temperature. A short period of rest, sleep, and refeeding restored the thermogenic response to cold, but thermal balance in the cold remained compromised until after several weeks of recovery when tissue insulation had been restored.  相似文献   
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