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排序方式: 共有1321条查询结果,搜索用时 15 毫秒
991.
: Fetal echocardiography has provided a means for the detailed assessment of cardiac structure and function from early prenatal life. Indications for a fetal echocardiographic examination and the potential implications for individuals caring for newborns with cardiac malformations are discussed. 相似文献
992.
Osseous lipoma: CT appearance 总被引:1,自引:0,他引:1
Characteristic radiographic and computed-tomographic (CT) features of seven cases of osseous lipoma are reported: six with medullary and one with parosteal locations. Radiological diagnosis of this lesion is discussed, with emphasis on potential pitfalls in interpretation of CT scans. Although the presence of fat-equivalent density on scans is highly suggestive of osseous lipoma, comparable attenuation is documented in cases of chronic osteomyelitis and postnecrotic subchondral excavation. 相似文献
993.
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996.
A national survey on informed-consent lawsuits that resulted from studies using contrast material revealed that 123 (8%) of 1,513 radiologists surveyed or others in their groups had been involved in informed-consent lawsuits. In response to a detailed follow-up questionnaire, 67 radiologists anonymously provided additional information regarding their lawsuits, which most often involved excretory urography (37%) or angiography (38%), with death or neurologic impairment the most common patient injuries. As a result of these lawsuits, many radiologists provide more detailed information to patients. In the United States, the total number of informed-consent lawsuits, however, was small in relation to the total number of studies done using contrast material. 相似文献
997.
Gallacher DJ; Kadir S; Kaufman SL; Mitchell SE; Kinnison ML; Chang R; Adams P; White RI Jr; Cameron JL 《Radiology》1985,156(3):625-629
Selected benign biliary strictures can be treated safely and successfully by percutaneous balloon dilatation. Primary biliary strictures appear to be less responsive to balloon dilatation alone and require stenting with large catheters (16-20 F) for several months to permit scarring around the catheter. A long period of healing around such a large-bore stent is crucial to the success of such treatment. The most important physiologic indicators for successful dilatation are a long period of stricture challenge with a catheter placed proximal to the dilated segment to allow bile to drain internally across the previously strictured segment, and a near anatomic result as demonstrated by cholangiogram. 相似文献
998.
Correction of canine cyclic hematopoiesis with recombinant human granulocyte colony-stimulating factor 总被引:3,自引:1,他引:2
Canine cyclic hematopoiesis (CH) is an autosomal recessive disease of gray collie dogs that is characterized by neutropenic episodes at 14- day intervals. The biochemical basis for CH is not known but may involve a regulatory defect of the response to or production of a hematopoietic growth factor. Administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to two CH and one normal dog caused a marked leukocytosis (greater than 50,000 WBCs) in all three dogs. The leukocytosis was due largely to a greater than tenfold increase in neutrophils. Less pronounced but significant elevations in monocytes occurred during G-CSF treatment. The elevated WBC count was maintained for more than 20 days in all three dogs, and two predicted neutropenic episodes were prevented in both CH dogs during rhG-CSF treatment. A decline in the WBC count occurred simultaneously in all three dogs during the last five treatment days and was presumably associated with the development of neutralizing antibodies to the heterologous rhG-CSF protein. Bone marrow evaluation indicated that the swings in the myeloid/erythroid progenitor cells that are characteristic of CH were eliminated by rhG-CSF treatment in both CH dogs. These results suggest that the regulatory defect in canine CH can be temporarily alleviated by treatment with rhG-CSF and point to the potential treatment of human cyclic neutropenia with this agent. 相似文献
999.
Relationship between human development and disappearance of unusually large von Willebrand factor multimers from plasma 总被引:1,自引:0,他引:1
Katz JA; Moake JL; McPherson PD; Weinstein MJ; Moise KJ; Carpenter RJ; Sala DJ 《Blood》1989,73(7):1851-1858
von Willebrand factor (vWF) multimers were examined in fetal, umbilical cord, and neonatal platelet-poor plasma (PPP) specimens. Sixty-five of 65 (100%) fetal PPP samples aged less than 35 weeks and seven of ten (70%) fetal samples aged greater than 35 weeks had unusually large vWF (ULvWF) multimers. Thirty of 46 (65%) cord PPP samples from neonates ranging in gestational age from 34 to 41 weeks had ULvWF. There was no significant relationship between either gestational age at time of delivery or birth weight and likelihood of finding ULvWF multimers in cord PPP samples. No maternal PPP sample contained ULvWF multimers. Serial heelstick samples from 16 preterm and term neonates were analyzed for 8 weeks. ULvWF multimers disappeared from the PPP of ten of the neonates during this time. The PPP of four neonates had vWF patterns similar to those in normal adult PPP throughout the sampling period. The ULvWF multimeric forms of fetal and neonatal PPP samples were similar to those constitutively released from endothelial cells. They were not as slowly migrating in a very porous 0.5% agarose gel system as the ULvWF multimers released from Weibel-Palade bodies in response to the calcium ionophore A23187. A vWF protomer was present in 97% of fetal samples, 83% of cord blood specimens, and 11% of neonatal heelstick samples, but was not found in any maternal sample. These results indicate that control mechanisms operative in older children and adults to prevent circulation of ULvWF multimers and vWF protomeric forms are normally acquired late in uterine life or during the neonatal period. ULvWF multimers, which are normal components of fetal, most cord, and some neonatal plasma samples, may contribute to in utero and postnatal hemostasis. 相似文献
1000.