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1.
Diagnosis Related Group (DRG) hospital payment has begun to squeeze hospitals financially and is likely to do so in the future. This study analyzed the relationship between the volume of urologic procedures by an individual urologist, hospital costs per patient, and outcome. We used a three-year DRG database of urology patients (N = 2,980) at an academic medical center to analyze these. Low-volume urologists (arbitrarily defined by us) had higher hospital costs per patient, financial losses versus profits under DRGs, and a poorer outcome when compared with high-volume urologists. Pearson correlation showed a positive relationship between cost per patient and physician volume for nonemergency patients (-0.129, p less than 0.0001) and emergency patients (-0.368, p less than 0.0001). This may have been explained (in part) by a greater severity of illness for patients of low-volume urologists. These findings suggest, however, that the volume of urologic procedures per urologist may be related to hospital resource consumption. The health care financing environment of the future should provide substantial interest in this finding for those involved in the consumption of urologic services.  相似文献   
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Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  相似文献   
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Piezo-electric extracorporeal lithotripsy with ultrasonographic detection is performed with the following material according to the following technique: 1) A mobile firing head connected to the lumbar region by a simple inflatable cushion filled with sterile water. At the centre of the firing head, a 5 MHz real time transducer is used to locate the stone. 320 piezo-electric elements, arranged around the transducer, can induce, when focussed, a pressure of about 900 bars at the focal point in vitro. The focus is 15 mm X 5 mm. The generators are electronic. 2) The technique requires: understanding of ultrasonography in order to precisely locate the stone which, when it is intrarenal, is only missed in 1% of cases in our experience. Stones of the iliac ureter are not visible. Treatment requires the patient's confidence so that, due to the quality of the piezo-electric wave, no anaesthesia is necessary. The firing time should be relatively long (45 min to 1 hr) in order to ensure good fragmentation. 26% of patients require retreatment. Secondary complications are rare (3% of endoscopic treatments). The technique is now proposed in 90% of cases without admission to hospital. The simplicity of the manipulation of the apparatus must not mask the fact that it is a technique which requires perfect mastery. Only urologists familiar with stone pathology and who are able to treat the complications of lithotripsy by endoscopy or by surgery should perform extracorporeal lithotripsy.  相似文献   
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Three hundred and sixty one extracorporeal lithotripsies for renal, ureteric and bladder stones have been performed by means of a system of ultrasonographic detection and piezoelectric destruction (EDAP LT01). The localisation of the stone is achieved by a 5 MHz real time sectorial transducer situated in the centre of a small dish containing 320 piezoelectric elements concentrated in a source 5 mm wide by 15 mm high. The pressure recorded in vitro is 900 bars. The stone is easily detected in 87.2% of cases, difficult to detect in 10% of cases and impossible to detect in 28% of cases. By using a frequency of 1.25 to 5 per second, extracorporeal lithotripsy can be performed without any local, regional or general anaesthesia and without premedication in the 120 patients with a renal stone, reviewed between 1 and 3 months, 88 (73%) were considered to be complete successes. Ten (8%) were considered to be failures and 19 (21%) were considered to be partial successes. The best results were obtained in stones of the renal pelvis less than 20 mm in diameter. These results relate to a mean series which must take into account the successive improvements made to the lithotripter. Today, stone fragmentation is obtained in 93% of cases. Thirty six stones of the lumber and pelvic ureter were treated with success rates of 93% and 50%, respectively. Six bladder calculi were treated with a 50% success rate. Forty two patients were treated without being admitted to hospital.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Kuross  SA; Hebbel  RP 《Blood》1988,72(4):1278-1285
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs.  相似文献   
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SMI-32, an antibody which recognizes the non-phosphorylated epitopes on the neurofilament proteins was used to study the morphological changes in the human striate cortex during postnatal development. Striate cortices from 12 autopsied patients with ages ranging from 1 day to 70 years were obtained. Using the avidin-biotin-peroxidase method, the first SMI-32 immunoreactive neurons were identified at sublayers Vb/VIa on the first postnatal day. At 5 months, the next group of neurons to develop immunoreactivity were in IVb. By 15 months, SMI-32 immunoreactive neurons were observed at III, IVa, IVb, V and VI. The changes in SMI-32 immunoreactivity (ir) were stabilized from 3 years and after. The SMI-32 ir in the striate cortex could be a useful morphological correlate for studying developmental diseases affecting the neocortex.  相似文献   
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