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141.
One of the possible complications of subclavian vein puncture is entry into the subclavian artery. If this is not recognized, a pacemaker lead may be placed arterially. Since this may lead to systemic emboli, the pacemaker lead must be removed. This case report describes a patient in whom an atrial lead was inadvertently placed in the ascending aorta, where it had good sensing values but poor atrial capture threshold values. This lead was subsequently removed and hemostasis was achieved with intraarterial balloon compression via the brachial artery.  相似文献   
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A complicated, almost critical situation has arisen in Ukraine in the early nineties in respect of drug maintenance of the population and health- and preventive-care institutions. Satisfaction of the public's needs for medicinal preparations was no more than 11 to 12% with home-made produce and up to 25% with foreign deliveries taken into account. Over the recent years (1995-1997), there has been a positive growing tendency in the total volume of home drug production (9 to 10% annually).  相似文献   
144.
P/midget ganglion cells mediate red-green color opponency in anthropoids. It has been proposed that these cells evolved as a specialization to subserve color vision in primates. If that is correct, they must have evolved about the same time as the long-wavelength ('red') and medium-wavelength ('green') pigment genes diverged, thirty million years ago. Strepsirhines are another group of primates that diverged from the ancestor of the anthropoids at least 55 million years ago. If P/midget ganglion cells evolved to subserve color vision, they should be absent in strepsirhines. We tested this hypothesis in a nocturnal strepsirhine, the greater bush baby Otolemur. The retinal ganglion cells were labeled with the lipophilic tracer Dil and the results show that bush babies have P/midget and M/parasol cells similar to those found in the peripheral retinas of anthropoids. A number of studies have shown that the P and M pathways of bush babies share many similarities with those of anthropoids, and our results show that the same is true for their retinal ganglion cells. These results support the hypothesis that the P system evolved prior to the emergence of red-green color opponency.  相似文献   
145.
Pediatric dual-energy X-ray absorptiometry spine scans often cannot be analyzed with standard software due to a failure to identify the bone edges of low density vertebrae. Low density spine (LDS) software improves bone detection compared with standard software. The objective of this study was to compare bone mineral density (BMD) measurements obtained with the standard and LDS software in 27 healthy nonobese, 32 obese, and 41 chronically ill children, ages 2-18 years. Lumbar spine (L1-L4) BMD, measured by standard analysis, ranged from 0.531-1.244 gm/cm2. Reanalysis with the LDS software resulted in a systematic increase (mean +/- SD) in estimated bone area of 17.0+/-5.0%, an increase in bone mineral content of 6.1+/-6.3%, and a mean decrease in BMD of 8.7+/-1.7% (all p < 0.001). This resulted in a mean decrease in BMD Z score of 0.7+/-0.2. Linear regression models, predicting standard BMD from LDS BMD, were fit for the three subject groups (R2 = 0.993-0.995). Small differences in slopes were detected across groups (p = 0.07); LDS BMD predicted higher standard BMD in obese subjects. In conclusion, LDS analysis resulted in a clinically significant decrease in measured BMD. The association between analysis methods was exceptionally high (R2 > 0.99), indicating that LDS BMD accurately predicts standard BMD. Although LDS BMD in obese subjects predicts higher standard BMD results than in nonobese subjects, the small difference is of questionable clinical significance. LDS software is a useful tool for the assessment of BMD in children.  相似文献   
146.
Incubation of mock-transfected PC12 rat pheochromocytoma cells (PC12) for 2 h with increasing concentrations of glutamate caused progressive loss of viability (e.g., 67% with 15 mM glutamate). In contrast, the viability of bcl-2-transfected cells (PC12/bcl-2) was unaffected by glutamate. Neither PC12 nor PC12/bcl-2 cells showed a significant incidence of apoptosis in response to glutamate. Conventional phospholipid analysis by high-performance TLC and phosphorous determination showed no significant changes in the phospholipid composition of either cell line incubated with 5 mM glutamate. The peroxyl radical initiator 2,2'-azobis(2,4-dimethylvaleronitrile) caused a pronounced loss of all major phospholipid classes in PC12 cells, but no loss of cell viability. No phospholipid peroxidation was detected in PC12/bcl-2 cells incubated with 相似文献   
147.
To investigate the repair of oxidative damage in DNA, we have established an in vitro assay utilizing human lymphoblastoid whole cell extracts and plasmid DNA damaged by exposure to methylene blue and visible light. This treatment has been shown to produce predominantly 7-hydro-8-oxodeoxyguanosine (8-oxodG) in double-stranded DNA at low levels of modification. DNA containing 1. 6 lesions per plasmid is substrate for efficient repair synthesis by cell extracts. The incorporation of dGMP is 2.7 +/- 0.5 times greater than the incorporation of dCMP, indicating an average repair patch of 3-4 nucleotides. Damage-specific nicking occurs within 15 min, while resynthesis is slower. The incorporation of dGMP increases linearly, while the incorporation of dCMP exhibits a distinct lag. Extracts from xeroderma pigmentosum (XP) complementation groups A and B exhibit 25 and 40%, respectively, of the incorporation of dCMP compared with normal extracts, but extracts from an XP-D cell line exhibit twice the activity. These data suggest that the efficient repair of 8-oxodG lesions observed in human cell extracts involves more than one pathway of base excision repair.  相似文献   
148.
The effects of an alternative chelation program in thalassemic patients with severe iron overload are investigated. The schedule of treatment, feasible at home, consists in the administration of deferoxamine intravenously (100 mg/kg/die 8 hours 10 days a month), followed by 50 mg/kg/die subcutaneously in the remaining 20 days of the month. The results in 34 patients who underwent this program over 8 months are reported. After intensive chelation therapy serum ferritin and transaminase levels were significantly lower, and daily urinary iron excretion values were significantly higher when compared to the levels observed before the treatment. After the period of study, echocardiography revealed an ejection fraction (EF) significantly higher in 15 out of 34 cardiopathic patients. In conclusion, the alternative chelation program is effective in reducing iron overload of thalassemic patients, protecting them also against cardiac disease.  相似文献   
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150.
Whether a high-resolving light scattering spectrometer may be used in medical practice is discussed in the paper. The results of the experiments on blood components and microorganisms are discussed.  相似文献   
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