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排序方式: 共有716条查询结果,搜索用时 140 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.
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
5.
A phase II trial of temozolomide and IFN-alpha in patients with advanced renal cell carcinoma. 总被引:1,自引:0,他引:1
Usha Sunkara Janet R Walczak Lori Summerson Theresa Rogers Mario Eisenberger Samuel Denmeade Roberto Pili Carol Ann Huff Victoria Sinibaldi Michael A Carducci 《Journal of interferon & cytokine research》2004,24(1):37-41
The combination of temozolomide (TEM) and interferon-alpha (IFN-alpha) previously demonstrated a 30% response rate in metastatic melanoma. A single institution, phase II trial evaluating the efficacy of TEM/IFN in patients with advanced renal cell carcinoma (RCC) was conducted. Safety and tumor response were the main outcomes. Eligible patients received 200 mg/m(2)/day TEM orally on days 1-5 every 28 days, with IFN 2.5 million U/m(2)/day subcutaneously (s.c.) three alternate days/week for days 1-15 first cycle, then 5 million U/m(2)/day s.c. 3 alternate days/week throughout each 28-day cycle. Efficacy was evaluated every 8 weeks, and dose-limiting toxicities (DLTs) were treated with dose reductions of the culprit drug. Sixteen patients (ages 37-67) were initially enrolled. Of the 14 evaluable patients, there was one minor response. Best response was stable disease, with 7 patients remaining on study for > or =6 months. Five were alive for more than 2 years, and 2 remain alive at 45 and 50 months after enrollment. DLTs included TEM-induced myelosuppression and IFN-induced fever/chills. Other toxicities were mild to moderate (grades 1-3). The combination of TEM/IFN proved quite tolerable. This regimen appears inactive in terms of response in this population with poor prognosis, but the patients with stable disease > or =6 months remain of interest. 相似文献
6.
A controlled trial of leuprolide with and without flutamide in prostatic carcinoma 总被引:26,自引:0,他引:26
E D Crawford M A Eisenberger D G McLeod J T Spaulding R Benson F A Dorr B A Blumenstein M A Davis P J Goodman 《The New England journal of medicine》1989,321(7):419-424
To test the hypothesis that maximal androgen blockade improves the effectiveness of the treatment of prostatic cancer, we conducted a randomized, double-blind trial in patients with disseminated, previously untreated prostate cancer (stage D2). All 603 men received leuprolide, an analogue of gonadotropin-releasing hormone that inhibits the release of gonadotropins, in combination with either placebo or flutamide, a nonsteroidal antiandrogen that inhibits the binding of androgens to the cell nucleus. As compared with the 300 patients receiving leuprolide and placebo, the 303 patients randomly assigned to receive leuprolide and flutamide had a longer progression-free survival (16.5 vs. 13.9 months; P = 0.039) and an increase in the median length of survival (35.6 vs. 28.3 months; P = 0.035). The differences between the treatments were particularly evident for men with minimal disease and good performance status; however, further studies should be conducted in this subgroup. Symptomatic improvement was greatest during the first 12 weeks of the combined androgen blockade, when leuprolide alone often produces a painful flare in the disease. We conclude that in patients with advanced prostate cancer, treatment with leuprolide and flutamide is superior to treatment with leuprolide alone. 相似文献
7.
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
8.
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
9.
X-ray diffraction by phospholipid monolayers on single-crystal silicon substrates 总被引:2,自引:2,他引:0
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Seul M Eisenberger P McConnell HM 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(18):5795-5797
Monolayers of dipalmitoyl phosphatidylcholine have been transferred from an air-water interface to single-crystal silicon wafers previously alkylated with octadecyltrichlorosilane. By using synchrotron radiation it has been found possible to observe diffraction by single-crystal regions of these monolayers with negligible background scattering from the solid substrate. In one series of experiments, diffraction signals at Bragg spacings of 0.4247 ± 0.0002 nm and 0.4253 ± 0.0002 nm were observed. The supported phospholipid monolayer crystals show remarkably high in-plane order: the positional coherence length is at least 500 nm and the orientational order is better than 0.01°. Preliminary temperature scans were carried out. The data reveal the existence of a phase transition at about 65°C. 相似文献
10.
Summary In 11 mongrel dogs both kidneys have been subjected to a 2 h ischaemic period. One kidney was cooled by perfusing the renal artery at 4°C while the contralateral normothermic kidney was clamped for 2 h. Studying the renal blood flow using the Xenon wash out technique, sequential renal scanning and angiography, marked differences between hypo- and normothermic ischaemia kidneys were observed. One or two hours following hypothermic perfusion a marked decrease of blood flow in the first compartment and vasoconstriction was evident, while within this period following normothermic ischaemia an enhanced renal blood flow was observed. After 24 h renal blood flow and renal function tested by 131I-Hippuran clearance returned to normal values. Angiographic studies corresponded to the preoperative findings. In contrast, normothermic ischaemia kidneys showed a decreased renal blood flow, impairment of kidney function in isotope studies and pathological angiographic changes.Supported by Deutsche Forschungsgemeinschaft 相似文献