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991.
992.
Hypertension in developing countries   总被引:2,自引:0,他引:2  
Population surveys carried out since the 1970s in 15 developing countries including 23 population groups show that the prevalence of hypertension ranges from as low as 1% in some African countries to over 30% in Brazil. A trend analysis of the mortality statistics for 35-74 year-olds from 16 countries in which data are available shows a downward trend in mortality from hypertension and cerebrovascular diseases in most of these countries. In spite of the current low prevalence in some countries, the total number of hypertensives in the developing world is high, and a cost assessment of possible antihypertensive drug treatment indicates that developing countries cannot afford the same drug treatment levels as developed countries.  相似文献   
993.
Totally, 185 patients, operated on for a fresh hip fracture, were randomly allocated to either methicillin antibiotic prophylaxis or no prophylaxis and followed for 1 month. Two superficial wound infections were recorded in the prophylaxis group and one in the control group. Prophylactic use of antibiotics in surgery for hip fractures seems unnecessary provided strict aseptic routines in the operating room are followed.  相似文献   
994.
The authors give an account of 190 premature infants they treated in 1956-1988, suffering from retinopathy of prematurity--ROP, and for prolonged subsequent periods. As the head of the team followed up all the children, there is an integrated view of the problem. The birth weight of the infants was 640 g--1,900 g. From the total number 76.8% infants had a birth weight of 1,500 g or less, 13.7% had a birthweight of 1,000 g or less. Evidence of the increasing rate is provided by the number of patients treated since birth at the department for premature and pathological infants FNM as well as by the number of children admitted from other departments after development of ROP. In 1956-1970, i. e. in 15 years, the authors looked after 34 patients, in 1971-1988, i. e. in 18 years there were 156 children with ROP. In 1956-70 cases of ROP predominated which developed as a result of absolute or relative hypoxia. They were successfully treated by individually adjusted and carefully controlled oxygen therapy (6.9% blind children). In 1971-1975 the possibility to use this therapy declined briskly because after introduction of modern medical technique the number of findings suggesting a hyperoxic insult increased. At that time the results deteriorated greatly (50% blind children). In 1976-1980 the results were favourably influenced by individual dosage of oxygen therapy in all infants, based on regular monitoring of blood gases (10.5% blind children).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
To obtain more insight into the effect of moderate alcohol intake on vitamin B-6 status indicators, we studied the associations of alcohol intake (unadjusted and adjusted for intake of vitamin B-6 and protein) with the erythrocyte aspartate aminotransferase activation coefficient (EAST-AC) and plasma pyridoxal 5'-phosphate (PLP) level. Data obtained from men (n = 224) and women (n = 217) aged 65-79 (nationwide sample in the Netherlands) were used for this purpose. Although alcohol intake (a maximum of 21% of the energy came from alcohol) tended to be positively associated with PLP, this association never reached statistical significance (p greater than or equal to 0.05). EAST-AC was inversely associated with alcohol intake, whether or not it was adjusted for vitamin B-6 and protein intake. Similar results were found for the total EAST activity (after adding PLP) or apoenzyme activity; the basal EAST activity (before adding PLP) or holoenzyme activity was not associated with the alcohol intake. These results indicate that caution is needed in the interpretation of the specificity of EAST-AC (i.e., the degree to which EAST-AC is unaffected by other factors) as an indicator of vitamin B-6 intake.  相似文献   
996.
The results of treatment of 160 patients with coccygodynia were analysed. The condition was caused by contusion, fracture or dislocation of coccygeal vertebrae or excess of osteochondral tissue around the coccyx. The patients were treated conservatively and surgically, 56 and 104 respectively. In 94 cases (50,3%) of surgically treated complete recovery was achieved. Surgery should be undertaken in cases not responding to conservative measures.  相似文献   
997.
1. Guanosine 3':5'-cyclic monophosphate (cyclic GMP) release and vascular tone was measured in the isolated kidney of the rat perfused at constant flow with Krebs-Henseleit solution. The effects of 3 vasodilators, acetylcholine (ACh), atrial natriuretic factor (ANF) and sodium nitroprusside (SNP) on the renal release of cyclic GMP and vascular tone were examined. The ability of the endothelial-derived relaxing factor (EDRF) inhibitors, haemoglobin and gossypol, to modify vasodilatation and vasodilator-induced changes in cyclic GMP releases from the kidney was also investigated. 2. Renal cyclic GMP release was elevated 8 fold by ANF (0.01 microM), 5 fold by SNP (1 microM) and 3 fold by ACh (0.3 microM). 3. For ACh, both the increase in renal cyclic GMP release and the vasodilatation were reduced by the EDRF inhibitors, haemoglobin (1 microM) and gossypol (15 microM). For SNP, neither the increase in renal cyclic GMP release nor vasodilatation were inhibited by gossypol (15 microM). 4. For ANF, neither the increase in cyclic GMP release from the kidney nor its vasodilator activity were affected by haemoglobin (1 microM). 5. EDRF inhibitors reduced the basal release of cyclic GMP from 0.32 +/- 0.06 pmol min-1 to 0.18 +/- 0.03 pmol min-1, gossypol being more effective than haemoglobin. 6. The results are consistent with the ability of ACh to induce EDRF-mediated vasodilatation in the isolated perfused kidney of the rat. Basal EDRF release appears to contribute approximately 50% to the basal release of cyclic GMP from this preparation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
Case report of a very large ectasia of the urethra in a 9 years old boy without any organic conflict and without any neuro-urologic trouble. It could be a particular syndrome.  相似文献   
999.
The scanning laser ophthalmoscope provided a high quality television image of the fundus with minimal illumination of the retina. This new device based on a totally new electro-optical principle allowed a detailed exploration of macular function directly under simultaneous fundus control. The focused beam of a yellow krypton laser (568,2 nm) was swept up and down, rights and links across the fundus to form a raster of parallel lines on the retina. The S.L.O. illuminated only a single retinal point at a time and illumination was reduced to less than 70 microw/cm2 versus 100,000 microns/cm2 for indirect ophthalmoscopy and 4,000,000 microw/cm2 for fluorescein angiography. The intensity of the laser beam could be modified with the microcomputer by means of an acousto-optic modulator. It was possible to produce static or dynamic graphic designs that were simultaneously viewed by the patient and observed by the examiner on the patient's fundus on the video monitor. Further computerized analysis of the videotaped scanning laser ophthalmoscopic images gave a functional retinal map with correction for shifts of stimulus position due to fixational saccadic eye movements. The map showed true retinal location of 1. fixation area; 2. scotoma. The clinical evaluation was completed with 3. measurement of visual acuity in any foveal or parafoveal location. The results of scanning laser ophthalmoscopy were illustrated with the report of datas in a patient with diffuse retinal pigment epithelial decompensation.  相似文献   
1000.
Tetanus toxin blocks Ca2(+)-evoked catecholamine release from permeabilized bovine adrenal chromaffin cells preloaded with gangliosides. Tetanus toxin preincubated with its specific antibodies F(ab')2 is without any effect on exocytosis. Specific antitetanus F(ab')2 presented to chromaffin cells which are pretreated with tetanus toxin and permeabilized by digitonin cannot restore exocytosis. Under the same conditions, however, 125I-labeled F(ab')2 accumulates in chromaffin cells. The accumulation depends on the presence and concentration of tetanus toxin and can be prevented by an excess of unlabeled F(ab')2. Once tetanus toxin has initiated block of exocytosis, it cannot be neutralized by binding to its specific antibody.  相似文献   
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