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排序方式: 共有637条查询结果,搜索用时 15 毫秒
561.
Hunter DW; Castaneda-Zuniga WR; Young AT; Cardella J; Lund G; Rysavy JA; Hulbert J; Lange P; Reedy P; Amplatz K 《Radiology》1985,156(2):341-348
Between May 1983 and October 1984, 51 patients who had 68 ureteral stones underwent treatment at the University of Minnesota. All 68 stones were removed successfully using percutaneous techniques. The 100% success rate is a great improvement over previous results at our institution. The primary factors appear to be the development of the retrograde-flush technique, familiarity with and access to a wider range of methods, and the increasing use of the retrograde ureterorenoscope to see stones in the lower ureter. The average patient was a 45-year-old man who had no other medical problems. The average hospital stay was 6.8 days. Experimental studies with dogs indicate that injection rates of up to 30 ml/sec of contrast material through a retrograde catheter in the ureter are safe if a vent is present in the upper collecting system. 相似文献
562.
Intravenous digital subtraction angiography was used to obtain a complete aortofemoral runoff examination of high diagnostic quality in a single patient session in eight patients. Using a 9-inch (22.9-cm) image intensifier, oblique and posteroanterior projections were obtained from the level of the aortic bifurcation to the tibial artery trifurcation. This technique is based upon the administration of one-half of the usual dose of contrast agent combined with a high frame-rate imaging technique and postacquisition integration to increase the signal-to-noise ratio. It is easily performed on an outpatient basis, lowers patient risk, and allows a significant savings of time, film, and cost compared with the conventional intra-arterial aortofemoral runoff examination. 相似文献
563.
Safe splenoportography 总被引:2,自引:0,他引:2
Brazzini A; Hunter DW; Darcy MD; Smith TP; Cragg AH; Castaneda-Zuniga WR; Amplatz K 《Radiology》1987,162(3):607-609
The records of 37 patients who had undergone splenoportography, including one group of 12 who were studied before 1976 and a second group of 25 who were studied after 1977, were reviewed. The primary difference was that in the second group, the tract in the spleen was occluded with absorbable gelatin sponge (Gelfoam) plugs as the needle was withdrawn. In addition, there were minor changes in technique, such as changes in the needle puncture angle and entry site. When the new technique was used, there was a significant decrease in the complications traditionally associated with splenoportography. This procedure is safe and deserves to be considered the procedure of choice in patients in whom precise anatomic information is needed preoperatively that cannot be obtained with noninvasive procedures such as ultrasound or magnetic resonance imaging. 相似文献
564.
Leach KR; Kurisu Y; Carlson JE; Repa I; Epstein DH; Urness M; Sahatjian R; Hunter DW; Casteneda-Zuniga WR; Amplatz K 《Radiology》1990,175(3):675-677
The thrombogenicities of stainless steel spring guide wires and two hydrophilically coated guide wires were compared. The guide wires were placed in canine femoral arteries for 30 minutes. The guide wires were removed, the thrombi were stripped off, and the clots were weighed. Clot weights obtained with the two hydrophilically coated guide wires were significantly less than those obtained with the stainless steel spring guide wires. The thrombogenicities of hydrophilically coated catheters and noncoated nylon catheters were compared with and without the use of heparin. Carotid arteries, jugular veins, femoral arteries, and femoral veins were used. Catheters were left in place for 45 minutes. The animals were heparinized and killed. The vessels were then removed en bloc with the catheter clamped in place. The vessels were incised, and the clot was removed and weighed. In arterial and venous catheterization, no significant difference in clot deposition was shown between the hydrophilically coated catheters and the noncoated nylon catheters. A striking reduction of thrombogenicity was achieved with heparinization of the catheters in both arteries and veins. 相似文献
565.
566.
The arthrographic image quality and relative morbidity resulting from use of Omnipaque 300 (iohexol), Hexabrix 320 (ioxaglate sodium meglumine), and Isopaque Coronar 370 (metrizoate) were compared in a prospective double-blind study performed with 120 patients. Radiographs obtained 2, 5, 10, 15, 20, and 25 minutes after injection were judged for diagnostic quality. Relative morbidity was evaluated by the physician during the examination and later by the patient via a questionnaire. Hexabrix demonstrated the best and most persistent diagnostic quality over serial radiographs (P less than .05). Omnipaque caused significantly less postprocedural pain (P less than .05). The other types of discomfort measured did not indicate statistically significant differences in morbidity resulting from the three contrast agents. 相似文献
567.
Hydropneumothorax: detection on supine radiographs 总被引:1,自引:0,他引:1
568.
Birth from cryopreserved embryos following in-vitro maturation of oocytes and intracytoplasmic sperm injection 总被引:2,自引:9,他引:2
Edirisinghe WR; Junk SM; Matson PL; Yovich JL 《Human reproduction (Oxford, England)》1997,12(5):1056-1058
This case report describes the birth of a baby following the transfer of
cryopreserved embryos generated from intracytoplasmic sperm injection
(ICSI) carried out on the second day after oocyte pick-up of
in-vitro-matured metaphase I and germinal vesicle stage oocytes. The couple
had a history of three failed intrauterine insemination attempts and
reduced fertilization rates in two previous in-vitro fertilization (IVF)
cycles. In the IVF-ICSI treatment cycle, 6/11 mature oocytes became
fertilized following ICSI on the first day. However, the patient failed to
conceive following the transfer of three embryos. Five oocytes were
immature (two at metaphase I stage and three with a germinal vesicle) and
these were cultured overnight. All had extruded a polar body by the
following day and ICSI was therefore performed; four oocytes became
fertilized, and were cryopreserved at the pronulear stage in propanediol.
In the next treatment cycle, transfer of frozen embryos was planned. The
pronuclear zygotes were thawed and cultured for 24 h prior to the transfer
of two embryos in a cycle stimulated with low doses of follicle stimulating
hormone. This resulted in a pregnancy and the delivery of a healthy baby
boy. In-vitro maturation of metaphase I and germinal vesicle oocytes which
are routinely collected in IVF-ICSI cycles, followed by second day ICSI
fertilization, may provide a valuable source of embryos for infertile
couples.
相似文献
569.
Glycoform composition of serum gonadotrophins through the normal menstrual cycle and in the post-menopausal state 总被引:7,自引:2,他引:7
Anobile CJ; Talbot JA; McCann SJ; Padmanabhan V; Robertson WR 《Molecular human reproduction》1998,4(7):631-639
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing
hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean
+/- SD) throughout their menstrual cycles and in five post- menopausal
women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7- 4) revealed
menstrual cycle stage- and postmenopausal-related differences in the serum
gonadotrophin charge. There were differences in the proportion of FSH with
an isoelectric point (pl) > 4.3 across phases of the menstrual cycle (P
= 0.019): midcycle (MC) 50%; early to mid-follicular (EMF) 36%; late
follicular (LF) 37%, luteal (L) 29% and following the menopause (PM) 17%.
There was no significant difference in the proportion of LH with pl >
6.55 between midcycle (53%) and EMF, LF or L phases (36, 43 and 32%
respectively); although all were greater than that found in the menopause
(13%). Concanavalin A chromatography revealed less (P < 0.005) complex
FSH and LH glycoforms at midcycle (63 and 13%) than in the EMF, LF and L
phases (90 and 18; 90 and 20 and 93 and 24% respectively). Menopausal
gonadotrophins were least complex (FSH 34%, LH 4%). There was a direct
relationship between serum FSH and FSH pl/complexity, and less acidic FSH
was associated with reduced FSH complexity. Increased oestradiol was
associated with basic FSH isoforms during the menstrual cycle and reduced
follicular phase FSH complexity. We conclude that changes in gonadotrophin
glycoforms occur through the menstrual cycle which are related to changes
in the prevailing steroid environment. Following the menopause oestrogenic
loss resulted in acidic, relatively simple glycoforms.
相似文献
570.
Balloon dilatation of excised aortic coarctations 总被引:2,自引:0,他引:2
Lock JE; Castaneda-Zuniga WR; Bass JL; Foker JE; Amplatz K; Anderson RW 《Radiology》1982,143(3):689-691
Seven children 1-6 years of age underwent aortic resection and re-anastomosis for coarctation of the thoracic aorta. The excised segments were 1-2 cm long and were dilated in vitro with a Grüntzig balloon catheter less than two hours after resection. A pressure of 4-8 atmospheres was used, and the inflated diameter of the balloon was twice the luminal diameter of the undilated coarctation. The diameter of each specimen was increased by an average of 85%, largely because of an increase in the external diameter of the coarctation. However, extremely high pressures were required for successful dilatation, producing transmedial tears in the "normal" aorta distal to the coarctation in three specimens. These results indicate that although balloon dilatation appears feasible as palliation for aortic coarctation, further studies of its safety are necessary before instituting clinical trials. 相似文献