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Beckmann  CF; Roth  RA; Luedke  MD 《Radiology》1986,159(3):643-645
In 44 patients with one or more calculi in the upper two-thirds of the ureter, single-stage percutaneous nephrolithotomy was performed through a middle or upper calyceal nephrostomy after cystoscopic placement of an occlusion balloon catheter distal to the calculus; in 42, the procedure was successful. The occlusion balloon catheter permitted retrograde opacification of all systems for enhanced renal puncture. In the last 30 patients an attempt was made either to push the calculus upward mechanically or to flush it upward into the renal pelvis with carbon dioxide or dilute contrast material. This was successful in 24 of these patients. Prior overnight occlusion of the ureter by means of ureteral dilatation further facilitates dislodgment of the calculus, which was successful in 12 of 13 patients.  相似文献   
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Elevated blood pressure is an important risk factor for renal-, cerebro- and cardiovascular diseases. We used an efficient discordant sib-pair ascertainment scheme to investigate the impact of the distal end of the long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing genes for the alpha1B and beta2 adrenergic receptors and the dopamine receptor type 1A on variation of systolic blood pressure in young Caucasians. We measured eight highly polymorphic markers spanning this positional candidate gene-rich region in 427 individuals from 55 three-generation pedigrees containing 69 discordant sibling pairs, and calculated multipoint identity by descent (MIBD) probabilities. The results of genetic linkage and association tests indicate that the region between markers D5S2093 and D5S462 is significantly linked to one or more polymorphic genes influencing interindividual variation in systolic blood pressure levels. Since the alpha1B adrenergic receptor and dopamine receptor type 1A genes are located close to these markers, these data suggest that genetic variation in one or both of these G protein-coupled receptors, which participate in the control of vascular tone, plays an important role in influencing interindividual variation in systolic blood pressure levels.   相似文献   
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Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
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Assessment of mitral regurgitant jets by three-dimensional color Doppler   总被引:1,自引:0,他引:1  
BACKGROUND: Color Doppler echocardiography is a standard technique for assessing mitral regurgitation before and after mitral valvuloplasty. Mitral valve prolapse produces complex eccentric jet flows that cannot be visualized and measured by two-dimensional color Doppler echocardiography. The aim of this study was to evaluate the clinical impact of three-dimensional color Doppler echocardiography, a new technique developed at our institution, for assessing mitral regurgitation. METHODS: Forty-five patients with mitral regurgitation underwent intraoperative transesophageal echocardiography and three-dimensional Doppler data acquisition. The grade of mitral regurgitation was assessed by angiography. The jet areas were calculated by planimetry from conventional color Doppler; the jet volumes were obtained by three-dimensional Doppler data. RESULTS: New patterns of mitral regurgitant flows were recognized according to the origin, direction, and spatial spreading into the left atrium. Conventional jet areas failed to separate the groups of patients with different degrees of regurgitation, whereas the jet volumes were able to divide patients with different regurgitation grades. No significant correlation was found between jet area and angiographic grading (r = 0.63, p = NS). Jet volumes were significantly correlated to angiography (r = 0.89, p < 0.001). CONCLUSIONS: Three-dimensional color Doppler echocardiography revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets.  相似文献   
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Inflamed fibronectin: an altered fibronectin enhances neutrophil adhesion   总被引:4,自引:0,他引:4  
Vercellotti  GM; McCarthy  J; Furcht  LT; Jacob  HS; Moldow  CF 《Blood》1983,62(5):1063-1069
Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation.  相似文献   
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The variation in colorectal cancer (CRC) incidence worldwide strongly suggests a role for dietary influences. Based on epidemiological data, protective effects of vegetables and fruit intake on CRC are widely claimed, while other data indicate a possible increased CRC risk from (higher) dietary fat intake. Therefore, we have investigated single and interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this study, four different diets (A-D) were compared, which were either low in fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced by a freeze-dried VFM. The diets were balanced so that they only differed among each other in fat/carbohydrate content and the presence of specific plant-constituents. Because the initiation of intestinal tumors in ApcMin mice occurs relatively early in life, exposure to the diets was started in utero. Without the addition of VFM, mice maintained at a high-fat diet did not develop significantly higher numbers of small or large intestinal adenomas than mice maintained at a low-fat diet. VFM added to a low-fat diet significantly lowered multiplicity of small intestinal polyps (from 16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male ApcMin mice only. Strikingly, addition of VFM to female mice maintained on a low-fat diet and to both sexes maintained on a high-fat diet significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7 polyps/mouse). In conclusion, our results indicate that neither a lower fat intake nor consumption of VFM included in a high-fat diet decreases the development of polyps in mice genetically predisposed to intestinal tumor development.   相似文献   
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