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991.
BACKGROUND AND AIMS: In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. METHODS: The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. RESULTS: Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. CONCLUSION: Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year.  相似文献   
992.
993.
Experimental Studies on Reproduction with the Lipid-RegulatingAgent Gemfibrozil. FITZGERALD, J. E., PETRERE, J. A., AND DELA IGLESIA, F. A. (1987). Fundam. Appl. Toxicol. 8, 454–464.Gemfibrozil, a new lipid-regulating agent, was evaluated inrats and rabbits for effects on various phases of the reproductionprocess. In teratology studies groups of pregnant rats and rabbitsreceived gemfibrozil at doses up to 200 mg/kg during organogenesis(rat, Days 6–15; rabbit, days 6–18). For peri- andpostnatal studies, groups of pregnant rats were given 92 or3 31 mg/kg from Day 15 of gestation through weaning. In fertilitystudies groups of sexually mature male rats were given 93 or326 mg/kg of gemfibrozil for 61 days and females were given94 or 318 mg/kg for 15 days prior to mating within treatmentgroups. Drug administration continued in females through gestationand weaning of the F1 offspring. In subsequent fertility experiments,treated male rats were mated with untreated females and treatedfemales were cohabitated with untreated males. Gemfibrozil didnot elicit a teratogenic response in either rats or rabbitsup to doses that resulted in maternal toxicity. Reduced pupweights during the neonatal and weaning periods in the femalefertility study as well as in the perinatal–postnatalstudy were the only apparent drug effect. Treatment of femalerats prior to mating had no significant effects on general reproductiveparameters. Male rats given doses of about 300 mg/kg/day showedinconsistent and equivocal lower rates of fertility relativeto the concurrent controls. No adverse effects were seen inthe reproductive performance of offspring of gemfibrozil-treatedmale rats.  相似文献   
994.
Acute effects of lamotrigine (BW430C) in persons with epilepsy   总被引:26,自引:19,他引:7  
Sixteen epileptic patients took single doses of lamotrigine, 120 mg or 240 mg. Six photosensitive patients showed reduction (with abolition in two) in photosensitivity after lamotrigine administration. Five subjects with frequent interictal spikes showed reduction in spike frequency over 24 h after lamotrigine administration. The half-life (t1/2) of lamotrigine in subjects taking sodium valproate was prolonged, whereas the t1/2 in subjects taking carbamazepine and/or phenytoin was reduced. The area under the curve of co-medication plasma levels was not affected by a single dose of lamotrigine. Five patients reported mild and generally transitory side effects; some of which represented exacerbation of preexisting complaints.  相似文献   
995.
The efficiency of preoperative laboratory screening of normal, healthy patients was investigated. Preoperative test results of 1311 consecutive patients were collected. Data on haemoglobin, serum potassium, serum creatinine and serum ALAT were routinely obtained. 736 patients were classified by history and physical examination as normal healthy persons not having any systemic disorder. In this group of patients no clinically relevant abnormal laboratory results were found under the age of 60 years. In the group of 60 years and older a significant number had elevated serum creatinine values.  相似文献   
996.
Chequerboard titrations carried out with modified serial dilutions of antibiotics such that consecutive concentrations in these series were four times smaller than those in two-fold serial dilutions enable MICs and MBCs to be determined with greater accuracy. Interaction indices calculated by this method can differ markedly from those calculated on the basis of two-fold serial dilutions. The differences calculated in this study ranged from -0.30 to +1.06.  相似文献   
997.
Infection is the most important cause of mortality in leucopenic patients. A broad spectrum antibiotic therapy is imperative in febrile and neutropenic patients. In a multicentric study we have used ceftazidime (100 mg/kg/d) and netilmicin (6 mg/kg/d) in 88 children (fever greater than or equal to 38.5 degrees C, neutropenia less than 500/mm3) treated for acute leukemias (59), non Hodgkin lymphomas (13) or solid tumors (16). Median age was 7 years (2 months-16 years). In patients who continued to remain febrile, vancomycin (40 mg/kg/d) was added after 48 hours. The effective treatment was continued until a neutrophil count greater than 1,000/mm3. The first combination (ceftazidime + netilmicin) was effective in 64 children (73%) and the second combination (ceftazidime + netilmicin + vancomycin) in 11 patients. Bacteria were isolated in 39 children: Escherichia coli: 9, Staphylococcus epidermidis: 9, Staphylococcus aureus: 8, Streptococcus: 6, Pseudomonas aeruginosa: 3, Streptococcus pneumoniae: 1, Haemophilus: 1, Klebsiella pneumoniae: 1, Proteus: 1, Serratia: 1, Flavobacterium: 1. In these 39 patients, 30 became apyretic with ceftazidime and netilmicin and 6 after vancomycin. All blood culture were negative after the first combination. The median duration of antibiotic therapy was 14 days (5-9 days: 28, 10-20 days: 43, greater than 20 days: 17). There were no death, no superinfection. Tolerance was good without kidney or liver or biological perturbation. We conclude that the combination ceftazidime and netilmicin is effective in neutropenic children.  相似文献   
998.
The autopsy findings in a clinically and biochemically documented case of adult-onset acid maltase deficiency presenting with limb girdle myopathy are presented. The skeletal muscles, tongue, extraocular and smooth muscles of gut and arterioles showed a vacuolar myopathy, most severely affecting proximal skeletal muscles. Muscle spindles were severely affected in all muscles. The heart showed basophilic degeneration and a vacuolar myopathy. The visceral organs and nervous system were morphologically normal. Possible mechanisms for this differential involvement of muscles and tissues are discussed.  相似文献   
999.
In a lizard (Gekko gecko) the anterograde tracer PHA-L was microiontophoretically applied to the predominantly serotonergic nucleus raphes inferior. Extensive spinal projections from the rostral magnocellular part of this nucleus were demonstrated to the superficial layers of the dorsal horn and to the intermediate zone, more sparsely to the ventral horn. But, in addition, retrogradely labeled neurons were found in and just below a periventricular cell group in tegmentum mesencephali, i.e. the laminar nucleus of the torus semicircularis, a cell group which receives spinal afferents and projects to the spinal cord as the mammalian periaqueductal gray. These data suggest the presence of a three-tiered pain control system in a lizard composed of projections from the laminar nucleus of the torus semicircularis to the rostral part of the inferior raphe nucleus which in its turn projects to the superficial layers of the dorsal horn of the spinal cord.  相似文献   
1000.
The cholinergic receptors in rabbit isolated rectus muscle preparations were characterized by means of cholinergic agonists and antagonists. The concentration-dependent contraction induced by acetylcholine, carbachol or oxotremorine remained uninfluenced by atropine (10(-5) M), whereas the nicotinic receptor antagonist hexamethonium caused a parallel shift of the concentration-response curve. The agonists pilocarpine, methacholine and aceclidine, which are selective muscarinic receptor stimulants, did not cause contraction of the muscle preparation. However, the nicotinic receptor stimulant 1,1-dimethyl-4-phenylpiperazine iodide (DMPP) caused contraction similar to that induced by acetylcholine. DMPP-induced contractions were inhibited by hexamethonium, causing a parallel rightward shift of the concentration-response curve. This shift could be quantified by means of a Schild plot, indicating competitive antagonism with a PA2 value of 4.63 for hexamethonium. Atropine when applied together with hexamethonium did not cause a further shift of the concentration-response curve. The present results clearly indicate that the cholinergic receptors which mediate contraction in the rabbit isolated extraocular muscle preparation belong to the nicotinic subtype.  相似文献   
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