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排序方式: 共有495条查询结果,搜索用时 31 毫秒
1.
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
2.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
3.
4.
Histological score for cells with irregular nuclear contours for the diagnosis of reflux esophagitis in children 总被引:5,自引:0,他引:5
Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa. 相似文献
5.
Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
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
6.
Serum pepsinogen I and gastrin concentrations in children positive for Helicobacter pylori. 总被引:2,自引:1,他引:2
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G Oderda D Vaira D Dell''''Olio J Holton M Forni F Altare N Ansaldi 《Journal of clinical pathology》1990,43(9):762-765
Serum pepsinogen I, serum gastrin concentration, and inflammatory scores were measured in a population of 71 children undergoing upper gastrointestinal endoscopy for investigation of upper abdominal pain. Forty four were initially colonised with Helicobacter pylori. The indices were measured before treatment (in 71 children), one month (in 41 children), and six months (in 21 children) after stopping treatment. Before treatment there was a significant correlation between serum pepsinogen concentration, total inflammatory score, and H pylori state, but no correlation between serum gastrin concentrations and H pylori state. Similarly, the total inflammatory score and serum pepsinogen concentrations were significantly correlated. There was no such correlation in children negative for H pylori. After treatment the inflammatory score improved in those patients in whom H pylori had been eradicated. There was also a significant fall in serum pepsinogen I and serum gastrin concentration in those patients in whom H pylori had been eradicated. These results were similar to those found six months after treatment had been stopped. These findings suggest that the serum pepsinogen I concentration could be considered a useful marker for gastritis and can be used as an index of severity of gastritis in H pylori positive subjects. The measurement of serum gastrin concentrations does not give useful information. 相似文献
7.
Prostaglandin E2 in gastric mucosa of children with Helicobacter pylori gastritis: relation to thickness of mucus gel layer.
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G Oderda M D'Alessandro P Mariani P Lionetti M Bonamico D Dell'Olio N Ansaldi 《Journal of clinical pathology》1993,46(9):836-839
AIMS--To evaluate the changes in mucus gel layer thickness and prostaglandin E2 (PGE2) content caused by Helicobacter pylori infection in the antral mucosa of children: to assess whether decreased mucus gel thickness is related to PGE2 production. METHODS--Antral biopsy specimens were taken at endoscopy from 153 children. H pylori gastritis was evident in 45 and normal mucosa in 59. The other 49 children were studied one month after antibiotic treatment that eradicated the infection in 37 of them had been stopped. One antral specimen was immersed in ice-cold saline, put under an inverse microscope with an eyepiece graticule. Mucus gel thickness was measured and then the processed for histological examination; another specimen was weighed and processed for in vitro prostanoid generation. RESULTS--Mucus gel layer thickness was significantly decreased in children with H pylori gastritis (90 (SD) 29) microns v 120 (58) microns in controls, p < 0.01) but returned to control values after H pylori had been eradicated. PGE2 generation was significantly increased in children with H pylori gastritis (1022 (811) ng/g v 641 (473) ng/g in controls, p < 0.01). One month after treatment PGE2 generation significantly decreased in children without infection (880 (534), p < 0.01), but was still high where infection persisted. A significant inverse correlation was found between PGE2 generation and mucus gel layer thickness (p < 0.05). CONCLUSIONS--These data suggest that H pylori damages the mucus gel layer, and that the gastric mucosa increases generation of PGE2 in response to back diffusion of acid and pepsin. 相似文献
8.
9.
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
10.
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