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91.
Fox DJ Doolabh VB Mackinnon SE Genden EM Hunter DA 《Restorative neurology and neuroscience》1999,15(4):319-326
OBJECT: This study evaluated the dose related effects of Cyclosporin A (CsA) alone and in combination with monoclonal antibodies (mAbs) directed against intercellular adhesion molecule-1 (ICAM-1) and the alpha subunit of leukocyte function-associated antigen (LFA-1 ) on peripheral nerve allograft rejection in a rat model. METHODS: Nerve regeneration was assessed using gait analysis of returning hind limb function, histology, and morphometry. RESULTS: Regeneration comparable to isograft controls and high dose CsA treatment groups was observed when mAbs were used in combi-nation with intermediate dose CsA. Intermediate dose CsA therapy without additional mAbs was insufficient to support this level of regeneration. Nerve allografts treated with high and low dose CsA demonstrated no increased benefit with the addition of mAb therapy. CONCLUSIONS: Thus, mAbs seem to have a dose dependent effect on immunosuppression when used in combination with CsA, and may have therapeutic promise as a rescue therapy when CsA levels fall or issues of toxicity become important. 相似文献
92.
In this work we use a computer simulation to estimate the magnitude of improvement in the signal-to-noise ratio of PET functional brain mapping studies as a function of partition coefficient and permeability surface product for O-14, F-17, and O-15 labeled flow tracers. A model for signal-to-noise ratio is derived from the Kety model for inert diffusible blood flow tracers. The results of the simulation suggest that moderate increases in partition coefficient and permeability surface product compared with water would lead to an increase in signal-to-noise ratio of a factor of about 3. 相似文献
93.
Walsh SV Antonioli DA Goldman H Fox VL Bousvaros A Leichtner AM Furuta GT 《The American journal of surgical pathology》1999,23(4):390-396
Infiltration of esophageal epithelium by eosinophils is seen in reflux esophagitis and allergic gastroenteritis. This study was performed to identify differences between patients with acid reflux esophagitis and those with non-acid reflux, possibly allergic, esophagitis. Intraepithelial eosinophils were demonstrated in posttherapy esophageal biopsy specimens in 28 children treated for gastroesophageal reflux disease (GERD). These patients were divided into three groups based on their response to treatment and the results of esophageal pH probe monitoring. Eleven patients (Group A) had incomplete clinical response and normal pH probe monitoring results. Ten patients (Group B) had incomplete response but did not have pH probe monitoring. These two groups formed the index population. Seven patients (Group C) had clinical improvement with GERD therapy and abnormal pH probe monitoring characteristic of GERD; they constituted the control population. Clinical, laboratory, and pathologic features were evaluated to detect differences between index and control populations. Dysphagia, food impaction, failure to thrive, peripheral eosinophilia, and abnormal allergen skin test results were detected only in Group A and B patients. Biopsy specimens of the distal 9 cm of the esophagus, after GERD therapy, contained larger numbers of eosinophils in Groups A and B than in Group C as shown on high-power fields (HPF) (A: 31/HPF +/- 19.5; B: 28/HPF +/-23.7; versus C: 5/HPF +/-6.7; p = 0.009). Eosinophil aggregates were identified only in Groups A and B (p = 0.07). Eosinophils located preferentially in the superficial layers of the squamous epithelium were noted only in Groups A and B (p = 0.02). Group A and B patients demonstrated clinical improvement when given antiallergic therapy. The authors identified a group of pediatric patients characterized by an allergic history, lack of adequate response to GERD therapy, normal esophageal pH probe monitoring results, and large numbers of eosinophils in esophageal biopsy specimens obtained after GERD treatment. On the basis of these features, the authors propose that these patients represent examples of allergic esophagitis. 相似文献
94.
95.
K Cartwright R Morris H Rümke A Fox R Borrow N Begg P Richmond J Poolman 《Vaccine》1999,17(20-21):2612-2619
The development of effective vaccines against serogroup B meningococci is of great public health importance. We assessed a novel genetically engineered vaccine containing six meningococcal class 1 (PorA) outer membrane proteins representing 80% of prevalent strains in the UK. 103 infants were given the meningococcal vaccine at ages 2, 3 and 4 months with routine infant immunisations, with a fourth dose at 12-18 months. The vaccine was well tolerated. Three doses evoked good immune responses to two of six meningococcal strains expressing PorA proteins contained in the vaccine. Following a fourth dose, larger bactericidal responses to all six strains were observed, suggesting that the initial course had primed memory lymphocytes and revaccination stimulated a booster response. This hexavalent PorA meningococcal vaccine was safe and evoked encouraging immune responses in infants. Vaccines of this type warrant further development and evaluation. 相似文献
96.
Sethi D Wheeler J Rodrigues LC Fox S Roderick P 《International journal of epidemiology》1999,28(1):106-112
BACKGROUND: One of the aims of the Study of Infectious Intestinal Disease (IID) in England is to estimate the incidence of IID presenting to general practice. This sub-study aims to estimate and correct the degree of under-ascertainment in the national study. METHODS: Cases of presumed IID which presented to general practice in the national study had been ascertained by their GP. In 26 general practices, cases with computerized diagnoses suggestive of IID were identified retrospectively. Cases which fulfilled the case definition of IID and should have been ascertained to the coordinating centre but were not, represented the under-ascertainment. Logistic regression modelling was used to identify independent factors which influenced under-ascertainment. RESULTS: The records of 2021 patients were examined, 1514 were eligible and should have been ascertained but only 974 (64%) were. There was variation in ascertainment between the practices (30% to 93%). Patient-related factors independently associated with ascertainment were: i) vomiting only as opposed to diarrhoea with and without vomiting (OR 0.37) and ii) consultation in the surgery as opposed to at home (OR 2.18). Practice-related factors independently associated with ascertainment were: i) participation in the enumeration study component (OR 1.78), ii) a larger number of partners (OR 0.3 for 7-8 partners); iii) rural location (OR 2.27) and iv) previous research experience (OR 1.92). Predicted ascertainment percentages were calculated according to practice characteristics. CONCLUSION: Under-ascertainment of IID was substantial (36%) and non-random and had to be corrected. Practice characteristics influencing variation in ascertainment were identified and a multivariate model developed to identify adjustment factors which could be applied to individual practices. Researchers need to be aware of factors which influence ascertainment in acute epidemiological studies based in general practice. 相似文献
97.
M Otsuka K Yoneoka Y Matsuda J L Fox W I Higuchi 《The Journal of pharmacy and pharmacology》1999,51(4):475-481
The effects of plasma calcium levels on oestradiol release from apatite bone cement and on the bone mineral density of ovariectomized rats have been investigated. Apatite cement was prepared from an equimolar mixture of tetracalcium phosphate, dicalcium phosphate dihydrate and 0.5% beta-oestradiol bulk powder. After subcutaneous implantation of the cement, oestradiol release in diseased rats (ovariectomized rats on a low-calcium diet) was significantly higher than in normal rats. The drug levels of recovery-model rats (ovariectomized, but on a high-calcium diet) were significantly lower than those of the diseased rats. Calcium levels in diseased rats remained low during drug release but the plasma calcium levels of the recovery-model rats increased. The areas under the plasma calcium concentration-time curves (Ca-AUCs) for the recovery-model rats were higher than those for the diseased-model rats. The plasma oestradiol concentration AUCs and the Ca-AUCs were linearly related. The body weight of the recovery-model rats increased after five days, but that of the diseased-model rats did not. The bone mass of the recovery-model rats was greater after the experiment than before. The relationship between the bone mineral density and Ca-AUC of the diseased rats suggested that bone mineral density increased with increasing Ca-AUC. The results suggest that the severity of osteoporosis in this animal model is reduced by implantation of the oestradiol-loaded apatite cement. 相似文献
98.
Trippodo NC Fox M Monticello TM Panchal BC Asaad MM 《Journal of cardiovascular pharmacology》1999,34(6):782-790
Vasopeptidase inhibitors are single molecules that inhibit neutral endopeptidase (NEP) and angiotensin-converting enzyme (ACE) simultaneously. Omapatrilat, the first in this new class of cardiovascular agents, potentiates vasodilatory and cardioprotective peptides and represses angiotensin II. This study compared the effects of omapatrilat with those of a pure ACE inhibitor on cardiac geometry and survival in animals with heart failure. BIO TO-2 cardiomyopathic hamsters (CMHs) in the early stages of dilated heart failure were treated with vehicle or maximal ACE inhibitory doses of captopril (750 micromol/kg/day) or omapatrilat (200 micromol/kg/day). Prolonged vasopeptidase inhibition increased median survival time after the start of treatment by 99 and 31% compared with vehicle and captopril, respectively (median survival times: 146, 221, and 290 days with vehicle, captopril, and omapatrilat, respectively; p < 0.001 for all comparisons). In similar CMHs, captopril or omapatrilat administered for 2 months significantly (p < 0.05) decreased heart weight, pulmonary congestion (lung weight), and left ventricular (LV) chamber volume compared with vehicle. Omapatrilat significantly increased LV mass-to-volume ratio compared with vehicle and captopril. Omapatrilat, but not captopril, significantly increased urinary atrial natriuretic peptide excretion, indicating NEP inhibition. Thus vasopeptidase inhibition with omapatrilat was more effective than ACE inhibition with captopril in preventing changes in LV geometry and premature mortality in hamsters with dilated heart failure. 相似文献
99.
Health maintenance organizations serve an estimated 20 percent of the child population, approximately 12 million children, many of whom have chronic conditions or disabling conditions. These children consume a disproportionate share of health resources and represent an important challenge in terms of care management. As HMOs increasingly enroll children with private insurance and Medicaid who have various physical, developmental, behavioral, and emotional disorders, they must find new and innovative ways to provide their care. Almost one third of children are affected by chronic conditions, and a smaller percentage (6 percent) suffer from chronic disabling conditions. Seven design elements for enhancing preventive and primary care for children with chronic conditions are presented in this article with illustrative examples from HMOs and state Medicaid programs. 相似文献
100.
The Gastric Bypass for Failed Bariatric Surgical Procedures 总被引:1,自引:0,他引:1
Background: Revision of failed bariatric surgical procedures is a significant challenge for every bariatric surgeon. Methods:
Evaluated are surgical difficulties, management problems and weight loss in patients with distal gastric bypass as a revisionary
procedure. Eighty patients were followed up to 3 years; four were lost to follow-up. Mean age was 43; mean prebariatric surgery
weight 134 kg; height 1.65 meters; body mass index 40.1; ideal body weight 62.7 kg; excess weight 70.5 kg; per cent excess
weight 214%. A 250 cm stomach-to-ileocecal valve segment of small bowel was used, and the biopancreatic secretions were brought
into the terminal ileum 100 cm from the ileocecal valve. Mean pouch size was 63 cc; length of hospital stay 5 days; operative
blood loss 616 cc; operative time 130 min. Results: Intraoperative complications included three splenic injuries (without
splenectomy). Early complications included one deep vein thrombosis, two marginal ulcers, one GI hemorrhage, one wound dehiscence,
one pouch outlet obstruction and one pancreatitis. Late complications included: one death from protein malnutrition/ARDS;
21 hypoproteinemia; six protein malnutrition, and of these, three had hyperalimentation; three cholecystitis; 27 anemia; 22
incisional hernia; two staple-line disruption (reoperated); 26 low serum iron; 11 prolonged (> 6 months) diarrhea; three prolonged
frequent vomiting; and two unrelated deaths (chronic myelogenous leukemia and amyotrophic lateral sclerosis). Mean excess
weight loss was 83% at 12 months; 89% at 24 months; and 94% at 36 months. Conclusion: The distal gastric bypass is fraught
with the operative and immediate post-operative complications experienced in any revisionary bariatric surgery. Distal gastric
bypass is very effective in producing long-term weight loss. Nutritional problems are common but usually easily corrected.
The most serious nutritional complication is protein malnutrition, which must be identified and corrected early. Success of
this procedure is dependent upon patient compliance with proper nutrition and supplements, and regular office follow-up with
monitoring of laboratory data. Patients who are noncompliant are at significant risk for complications. 相似文献