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991.
The present study determined the effect of chronic PPA infusion and withdrawal on weight regulation. Male Sprague-Dawley rats received PPA (0, 90 or 180 mg/kg) via miniosmotic pumps for 2 weeks. Body weight and food and water consumption were measured daily before, during, and for 2 weeks after PPA infusion. Additionally, body weight was measured once 6 weeks after the last day of drug administration. PPA infusion produced dose-dependent reductions in body weight and food consumption throughout drug administration. During the first week of PPA termination, food consumption returned to control levels; however, body weights of drug-treated animals remained below those of controls throughout the 6-week post-drug period. PPA depressed water intake during the first week of drug administration, but tolerance to this effect developed by the second week of administration. These results suggest chronic PPA infusion produces persistent appetite suppression and weight loss and that discontinuation of PPA does not result in hyperphagia or rapid weight gain. These findings may have clinical significance for the many individuals who wish to lose weight but have difficulty reducing intake without pharmacologic assistance.  相似文献   
992.
Forty-five patients were prospectively studied during the first 100 days after allogeneic marrow transplant to determine the relationship between cytomegalovirus-specific gamma-interferon and interleukin 2 production by peripheral blood mononuclear cells and CMV infection. IL-2 production was significantly lower than normal throughout the study period (P = 0.0001). In contrast, mitogen-induced gamma-interferon production was in the normal range by days 41-60 while CMV antigen induced gamma-interferon production by PBMC was normal by 81-100 days after transplant. Antibody- and complement-depletion studies showed that T4 helper cells were capable of gamma-interferon production in response to CMV antigen despite deficient IL-2 production. Neither gamma-interferon nor IL-2 production distinguished CMV-infected from uninfected patients. However, CMV-infected patients had significantly more T8 cytotoxic/suppressor cells than did uninfected patients by 81-100 days after transplant (P = 0.001). In vitro addition of IL-2 significantly increased gamma-interferon production by PBMC from patients with reduced production, suggesting that decreased gamma-interferon production may be related to deficient IL-2 production. Deficiencies in both CMV-specific IL-2 and gamma-interferon production may contribute to the high frequency and severity of CMV infection after marrow transplantation.  相似文献   
993.
We studied data on seizures, vacant spells and breathing dysrhythmia from the British Rett Survey and 150 electroencephalographic records from 78 classic cases, including 23 with prolonged synchronous recordings of EEG, respiration and movement. The proportion of abnormal records increased from 6 of 18 (33%) during the first 6 months of the regression period to 44 of 59 (75%) in the later period to 6 years, the increase in abnormality following rather than preceding the onset of regression. In young girls the EEG abnormality increased in sleep but decreased during episodic hyperventilation and breath-holding. Epileptogenic activity was commonly present without clinical seizures. Eleven vacant spells were monitored and were not epileptic but related to the breathing abnormality. Full monitoring is essential when supposed seizures are intractable. The intermittent EEG abnormality and behavioural changes indicate abnormal fluctuating arousal possibly of midbrain or brainstem origin.  相似文献   
994.
Third Degree Anal Sphincter Tears: Risk Factors and Outcome   总被引:2,自引:0,他引:2  
Summary: The aim of this retrospective study was to determine the incidence, risk factors and anal symptoms related to third degree tears after vaginal delivery. There were 9, 631 vaginal deliveries during the 5-year period studied, with 116 (1.2%) having a third degree tear. Statistically significant risk factors for a third degree tear were primiparity, forceps delivery, episiotomy, fetal birth-weight greater than 4,000 g and increased duration of the second stage of labour. Eighty four of the 116 women were able to be interviewed, and 21 (25%) had anal symptoms related to the tear. Only 3 women had sought help for their symptoms. Twelve women experienced anal incontinence and 2 more required delayed repair of the anal sphincter for incontinence. Third degree tears are a major cause of perinatal and postnatal morbidity. Attention needs to be directed to the prevention of such tears by awareness of the women at risk and to better follow-up and counselling of the women sustaining a tear.  相似文献   
995.
To design appropriate interventions, we collected clinical and demographic data prospectively on all children aged one day to 14 years admitted with a diagnosis of bacterial meningitis (BM) from April 1st 1996 to March 31st 1997 to the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi. During the study period 267 children (2.7% of all paediatric admissions) were found to have BM; 83% were under 5 years of age, 61% under one year and 23% under one month. The most common causative organisms in the post neonatal period (n= 206) were Streptococcus pneumoniae (27%), Haemophilus influenzae type b (Hib) 21%, and Salmonella typhimurium (6%). In the neonatal group (< 1 month, n= 61) the most common causes were Streptococcus agalactiae (23%), S. typhimurium (15%), S. pneumoniae (11.5%) and other Gram negative rods (11.5%). Nineteen of 21 salmonella infections were in children under one year of age and all S. agalactiae were in infants under three months. There was delay on presentation: the average length of fever was 4.6 days, 39.5% had convulsed prior to arrival and 57% had an altered level of consciousness. An initial diagnosis of malaria had probably contributed to the delay in 22.5% (42 of 186 tested). 48% were < 80% weight for age, with 18% < 60% weight for age. The overall mortality was 40%. The outcome was worst in salmonella infections, particularly neonatal salmonella BM with a case fatality rate (CFR) of 89% (8 of 9 cases). Coma on presentation worsened prognosis (mortality 64% if Blantyre Coma Score < 3, 26% if > 3). 15% of survivors had sequelae on discharge. 20% of Hib isolates were resistant to chloramphenicol, but all salmonellae were sensitive. 5% of S. pneumoniae were resistant to penicillin and 8% to chloramphenicol. Earlier access to adequate health care and awareness of BM in a malaria-endemic area would reduce mortality and morbidity. Vaccination against Hib infection would have reduced death by 18 (17%) and prevented sequelae in 7 cases.  相似文献   
996.
Retinoic acid (RA) treatment of F-9 embryonal carcinoma cells resulted in cell flattening and increased production of laminin B1 chain, both indicating differentiation to endoderm-like cells. In addition, RA caused a time- and dose-dependent decrease in growth rate in monolayer culture and a dose-dependent decrease in the ability of the cells to form colonies in soft agarose. Differentiation was accompanied by an increase in the fucosylation of specific high-molecular-weight cellular and cell-surface glycoproteins. The fucosylation of glycoproteins of Mr 175,000 (gp175), 250,000 (gp250), and 400,000 (gp400) increased as early as 24 hr after the addition of 5 x 10(-6) M RA to the culture medium. These changes preceded both growth inhibition and the induction of laminin B1 expression, which were detected 48 to 72 hr after addition of RA. The increased fucosylation of these glycoproteins showed a distinct dose-response relationship. Both gp175 and gp250 showed the greatest increase in fucosylation at 10(-5) M, which was also the dose at which RA induced laminin maximally, while the fucosylation of gp400 was greatest at 10(-8) M RA and declined at higher concentrations. The overall synthesis of large fucosylated glycopeptides decreased in RA-treated cells, in spite of the increases in the fucosylation of specific cellular glycoproteins. RA-induced differentiation of F-9 cells was also accompanied by a time- and dose-dependent increase in fucosyltransferase activity. Although the functions of these glycoproteins are not currently known, the early increase in their fucosylation can be considered as a marker of differentiation in this system.  相似文献   
997.
The prevalence of commissural lip pits in a group of 2462 Israeli Jews was determined, and a relation of commissural lip pits to ethnic background was noted. Results showed the presence of commissural lip pits in 17.4% of the entire sample; 9.7% were unilateral and 7.7% were bilaterally located. The Ashkenazi group showed a significant higher prevalence of commissural lip pits (19.4%) when compared to the prevalence in the Sephardic group (14.1%) and the Eastern group (21.1%).  相似文献   
998.
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1000.
HL-A-Linked Human Immune-Response Genes   总被引:8,自引:0,他引:8       下载免费PDF全文
Genetic control of the response to specific natural-product antigens has been documented in three informative families. Families were selected on the basis of probands with tuberculosarcoidosis, chronic cutaneous moniliasis, and rheumatoid arthritis. An increased incidence of delayed cutaneous unresponsiveness was observed in each family. Positive associations were identified between HL-A haplotypes and immediate cutaneous hypersensitivity responses to 5, 8, and 11 of 23 test antigens in the three respective families. HL-A-associated differences in averaged responses of cutaneous hypersensitivity were excluded. These significant associations are consistent with linkage between HL-A haplotypes and genes responsible for the immune response to various natural-product antigens.  相似文献   
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