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91.
A large variation in seasonal weight loss between individuals exists in rural communities in developing countries. Therefore, it was investigated whether some individuals show a metabolic adaptation and, through that, prevent large body-weight losses during the preharvest season. Basal metabolic rate (BMR), energy intake and physical activity level (PAL) of rural Beninese women were measured in three seasons. Groups of subjects were: women with a body mass index (BMI) < 18 (n 18), and a BMI > 23 (n 16), and women who had shown small (n 18) and large (n 15) preharvest weight loss. All groups of subjects decreased energy intake during the preharvest season by 0.66-1.09 MJ/d. PAL did not show significant seasonal changes in any of the four groups. Only subjects with a BMI < 18 decreased BMR during the preharvest season with 2.9 (SD 6.7) J/kg per min (P < 0.05), with a decrease of 0.8 (SD 1.4) kg (P < 0.05) in body weight. In very thin women with a BMI < 17 (n 5) BMR expressed per unit body weight decreased even more during the preharvest season (by 12%).  相似文献   
92.
The patients with strabismus, including 8 with superior oblique paresis, 1 with inferior rectus paresis, and 1 with congenital constant exotropia, were examined with MR imaging at 1.5 tesla (T) or 0.5T with a surface coil. Abnormal findings of extraocular muscles were identified in 8 of the 10 patients and most of them were consistent with the clinical findings. Deviation of the optic nerves was noted in 5 patients. Coronal short repetition time (RT) and echo time (ET) images were used to measure the concerned extraocular muscles and the optic nerves. The differences in diameters between the concerned extraocular muscles of both the diseased and normal eyes were calculated. MR imaging is considered to be advantageous and can be favorably used to observe and measure the extraocular muscles and other intraorbital structures in patients with strabismus.  相似文献   
93.
Hyperadrenocorticism is recognized as a common medical condition in middle- to old-aged ferrets. Because diagnosis of adrenocortical tumors in ferrets, using results of adrenocorticotropic hormone stimulation or dexamethasone suppression tests, is unreliable, ultrasonography was used as an alternative to laparotomy for the detection of tumors in 2 ferrets. The diagnosis was confirmed by surgical excision and histologic examination of the adrenal gland. In a typical manifestation of the condition, clinical signs in 1 ferret included vulvar swelling and serous to mucopurulent vaginal discharge, which resolved after the adrenalectomy.  相似文献   
94.
BACKGROUND: Long-term corticosteroid therapy for Crohn's disease is associated with important types of morbidity, such as osteoporosis. Safe and effective alternative treatments are required. Although a short-term benefit of cyclosporine in active Crohn's disease has been suggested, the long-term safety and efficacy of this treatment have not been established. METHODS: We conducted a randomized, double-blind, placebo-controlled evaluation of the effect of 18 months of low-dose cyclosporine treatment on the course of Crohn's disease. Adult patients whose disease had been active within the previous two years were randomly assigned to receive cyclosporine (151 patients) or placebo (154 patients) in addition to their usual therapy. Randomization was stratified according to center and score on the Crohn's Disease Activity Index (193 patients had scores of 150 or less, and 112 had scores greater than 150). The primary outcome measure was clinically important worsening of Crohn's disease, defined as a 100-point increase in the Crohn's Disease Activity Index from the patient's base-line value. Secondary outcomes were the use of prednisone and 5-amino-salicylates, mean score on the Crohn's Disease Activity Index and mean quality-of-life score, and the need for surgery. RESULTS: The condition of more patients worsened with cyclosporine than with placebo (91 of 151, or 60.3 percent, vs. 80 of 154, or 51.9 percent; P = 0.10). The median time to worsening of disease in patients receiving cyclosporine was 338 days, as compared with 492 days in patients receiving placebo (P = 0.25; relative risk, 1.22; 95 percent confidence interval, 0.86 to 1.72). Analyses of the mean Crohn's Disease Activity Index and quality-of-life scores and of the use of prednisone and 5-aminosalicylates also failed to demonstrate benefit. CONCLUSIONS: In our patient population, the addition of low-dose cyclosporine to conventional treatment for Crohn's disease did not improve symptoms or reduce requirements for other forms of therapy.  相似文献   
95.
96.
We have measured haemodynamic responses to induction of anaesthesia, laryngoscopy and intubation in 103 mild-moderate hypertensive patients (83 patients (diastolic pressures < or = 110 mm Hg) currently receiving one of four monotherapies (ACE inhibitors, group A; beta adrenoceptor blocking drugs, group B; calcium channel antagonists, group C; diuretics, group D) and 24 were untreated hypertensive patients). Anaesthesia was induced with fentanyl 1.5-2.0 micrograms kg-1 and thiopentone 3-5 mg kg-1. Tracheal intubation was facilitated by vecuronium 0.1 mg kg-1 and anaesthesia maintained with enflurane and nitrous oxide in oxygen. Systolic and diastolic pressures (SAP, DAP) were measured at 1-min intervals by a non-invasive oscillometric method and cardiac output (CO) and stroke volume (SV) by thoracic bioimpedance. Induction of anaesthesia was associated with a decrease in SAP, DAP and CO in groups A-D (P < 0.05). Heart rate (HR) decreased in groups A and D (P < 0.01) and systemic vascular resistance (SVR) decreased in groups A and B (P < 0.05). SAP and HR increased in all groups after laryngoscopy and intubation (P < 0.01) as did SVR in groups A, B and D (P < 0.02). CO was unaltered. Similar changes occurred in the untreated hypertensive patients, although nine of 24 patients exhibited HR > or = 100 beat min-1 after laryngoscopy and intubation. Comparison of the changes in SAP, DAP, CO and SVR with time showed no differences in the five treatment groups; changes in HR were significantly less in group B compared with the other groups (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
97.
98.
The binding of 5-fluorodeoxyuridylate (FdUMP) to carboxypeptidase-inactivated thymidylate synthase obtained from methotrexate-resistant Lactobacillus casei was investigated using [3H]FdUMP in a trichloroacetic acid precipitation assay and by 19F nuclear magnetic resonance spectroscopy. The cleavage of 1 valine residue from the carboxyl terminus of one of the identical subunits of the enzyme dimer correlates with complete loss of thymidylate synthesis (Aull, J. L., Loeble, R. B., and Dunlap, R. B. (1974) J. Biol. Chem. 249, 1167-1172). We have further investigated the phenomenon of carboxypeptidase A-dependent inactivation of thymidylate synthase by employing immobilized carboxypeptidase A in order to facilitate the isolation and characterization of the inactivated enzyme. The time course of carboxypeptidase treatment of thymidylate synthase has been profiled by the spectrophotometric assay, tritium release assay, trichloroacetic acid precipitation assay (covalent adduct analysis), 19F nuclear magnetic resonance spectroscopy, and amino acid analysis. The techniques utilized in this study yielded results which showed that the completely inactivated enzyme (failure to catalyze thymidylate formation) continued to catalyze both covalent FdUMP-enzyme interactions and the formation of the covalent inhibitory ternary complex with the cofactor, 5,1O-methylenetetrahydrofolate, although to a reduced extent, thus effectively uncoupling these processes from thymidylate synthesis activity.  相似文献   
99.
A card survey was sent to 340 veterinarians in the Urban, Delta, Highland and Coastal Plain regions of Arkansas. Veterinarians were asked to indicate numbers of dogs tested, confirmed Dirofilaria immitis positive, diagnostic techniques, frequency and period tested. A significantly greater percentage of dogs tested D. immitis positive in the Delta region as compared with the Urban region. There were no significant differences in the percentage of treated dogs on prophylaxis or the types of diagnostic tests among regions.  相似文献   
100.
Fluorescence in situ hybridization (FISH) is a powerful tool for detection of numerical and structural chromosomal aberrations. We have compared conventional banding techniques and FISH for the detection of monosomy 7 (-7) and trisomy 8 (+8) in 89 patients with myeloid malignancies. Of these patients, 21 had -7, 30 had +8, four had both, and 34 had no aberrations or aberrations other than -7 or +8 as assessed by banding techniques. Sequential samples were available in 23 patients. Alphoid DNA probes specific for chromosomes no. 7 and 8 were used for FISH. As controls, 10 normal bone marrow (BM) samples were hybridized with the chromosomes no. 7 and 8 probes, and in addition all tumor samples were hybridized with a chromosome no. 1 specific probe. The cut-off value for -7 was 18% one-spot cells, and for +8 was 3% three-spot cells. FISH analysis of 44 samples with -7 or +8, and at least 10 metaphases evaluated, showed that the proportions of aberrant metaphase cells mirrored the interphase clone sizes. Most samples with nonclonal metaphase aberrations, including those with only a few metaphases, had increased numbers of aberrant interphase cells: 20% to 80% for -7, and 3% to 43% for +8. Interphase cytogenetics of the 34 samples without -7 or +8 did not show significant cell populations with -7 or +8. In four patients, -7 or +8 could not be confirmed by FISH due to additional structural aberrations, marker chromosomes, or wrongly interpreted banding results. As FISH will be used more and more in cytogenetic diagnosis, clinical follow-up, and therapy monitoring, it will be necessary to standardize FISH procedures and supplement the Standing Committee on Human Cytogenetic Nomenclature (ISCN) definitions of a clone with criteria specifically for in situ hybridization.  相似文献   
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