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91.
Shellock  FG; Crues  JV 《Radiology》1987,163(1):259-262
Temperature, heart rate, and blood pressure responses to high-field-strength magnetic resonance (MR) imaging were studied in 50 patients who underwent procedures at exposures to radiofrequency radiation above the present recommended whole-body average specific absorption rate (SAR) of 0.4 W/kg. Body temperature significantly increased an average of 0.2 degrees C. The highest body temperature recorded after MR imaging was 37.5 degrees C. There was no significant correlation between the change (before and after imaging) in body temperature and whole-body average SARs. Changes in skin temperatures were variable, depending on anatomic site. The largest change was 3.5 degrees C, and the highest skin temperature recorded after imaging was 35.1 degrees C. There was a modest correlation between the change in skin temperatures and whole-body average SARs. Average heart rate and average mean blood pressure measured immediately before imaging were not significantly different afterward. High-field-strength MR imaging at the whole-body average SARs of 0.42-1.2 W/kg studied was not associated with any temperature- or hemodynamic-related deleterious effects.  相似文献   
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93.
Administration of recombinant canine granulocyte-macrophage colony- stimulating factor (rcGM-CSF) to normal dogs in previous studies induced an increase in peripheral blood neutrophils and a dose- dependent decrease in platelet counts. In six dogs that received the highest tested dose of rcGM-CSF (50 micrograms/kg/d) for a minimum of 12 days, the mean nadir of the platelet count was 46,000/microL (range, 4,000 to 91,000/microL) on day 9 +/- 1.1 after starting therapy, compared with a mean baseline platelet count of 398,000/microL (range, 240,000 to 555,000/microL). In three dogs, survival of autologous 111In- labeled platelets was reduced from a mean of 4.9 days to 1.3 days during the administration of rcGM-CSF. Biodistribution studies with gamma camera imaging indicated that there was an increase in mean hepatic uptake during the administration of rcGM-CSF, from 15% to 44% of the total injected 111In-labeled platelets at 2 hours, whereas splenic uptake was not significantly changed. In contrast, in two evaluable dogs who were recipients of 111In-labeled platelets from matched allogeneic donors receiving rcGM-CSF, platelet survival was not reduced and no increased hepatic uptake was noted. A third dog became alloimmunized to the matched donor platelets and was not evaluable. Immunohistologic studies of liver and spleen were performed with monoclonal antibodies specific for canine gpIIb/IIIa and P-selectin in dogs treated with rcGM-CSF and compared with untreated controls. On treatment, a marked reduction of platelets in the red pulp of the spleen was evident, and in general, the presence of platelet antigen in the liver was unchanged. Therefore, platelets were not being sequestered, but destroyed in the liver and spleen. The platelet antigens, P-selectin and gpIIb/IIIa, were identified in association with Kupffer cells in the liver, but no difference in the number of distribution of these Kupffer cells was found between controls and rcGM- CSF-treated dogs. In the spleen during rcGM-CSF treatment, most platelet antigens were associated with large mononuclear cells in the marginal zone. During administration of rcGM-CSF, CD1c and CD11c expression was increased on Kupffer cells. Platelet P-selectin expression and binding of leukocytes to circulating platelets were unchanged from baseline studies with rcGM-CSF treatment. In conclusion, during the administration of rcGM-CSF to dogs, a local process in the liver and spleen is induced resulting in thrombocytopenia.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
94.
Storb  R; Raff  RF; Appelbaum  FR; Graham  TC; Schuening  FG; Sale  G; Pepe  M 《Blood》1989,74(3):1139-1143
We explored the ability of fractionated total body irradiation (TBI) given at a rate of 7 cGy/min from opposing dual 60Co sources at otherwise lethal doses of 450, 600, 700, 800, and 920 cGy to condition dogs for marrow grafts from DLA-identical littermates. Results were compared with those of a previously reported study using single-dose TBI administered under otherwise identical conditions. Fractionated TBI was less immunosuppressive than single-dose TBI, as evidenced by a significantly higher rate of graft rejection (P = .001). Specifically, sustained allogeneic engraftment was observed in only two of 18 (11%) dogs that received 600 to 800 cGy fractionated TBI as compared with 11 of 17 (65%) dogs that received comparable doses of single-dose TBI. Only at 450 cGy (none of the ten dogs studied had sustained engraftment) and at 920 cGy (four of five dogs that received fractionated and 20 of 21 dogs that received single-dose TBI engrafted) were we unable to find differences between the two modes of radiation. Most dogs that rejected their graft survived with autologous recovery (13 of 22 that received fractionated and eight of 12 that received single-dose TBI; P = .49), presumably the result of extended support provided by the transient allogeneic grafts. We conclude that at equivalent doses fractionated TBI is significantly less effective than single-dose TBI to condition DLA-identical littermate dogs for marrow transplantation. These findings have implications for the design of conditioning programs in clinical transplantation, especially when T- cell-depleted marrow grafts are used.  相似文献   
95.
Cryptosporidium parvum is an underdiagnosed cause of diarrhea in children. The case of a 1-year-old girl with short bowel syndrome presenting with severe dehydrating diarrhea with a protozoon named C parvum is reported. Although the resection of the small bowel in this patient seemed to cause this severe infection with C parvum, more cases are needed to include the resection of the small bowel as a risk factor for Cryptosporidium infection and/or for a more severe form of diarrhea. Awareness of this infection among clinicians will help to diagnose this infection since special acid fast staining is made on special request.  相似文献   
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97.
Objectives. To evaluate cases of partial hydatidiform mole coexisting with a live fetus, including an observation of our own, and to discuss the proper antenatal management of women wishing to continue with a partial molar pregnancy.

Method. A PubMed search was then undertaken, extending over the time period from 1975 to 2006, using the keywords ‘partial hydratidiform mole’, ‘hydatidiform mole’ and ‘coexisting fetus’.

Results. At 16 weeks of gestation, an ultrasonographic examination revealed a normal fetus with an extremely large, multicystic placenta. The woman was informed of future risks but wished to continue with the pregnancy. The pregnancy progressed until 28 weeks without any complication but ended spontaneously with a vaginal delivery; the fetus had died in utero. Pathologic examination of the placenta revealed areas of hydropic degeneration and necrosis. Including our own observation, 17 cases of partial hydatidiform mole associated with a fetus of normal karyotype have been documented.

Conclusion. Although the rate of adverse perinatal outcome is high, we still believe that if amniocentesis or fetal blood sampling reveals a normal karyotype, then continuing the affected pregnancy with close follow-up in tertiary centers is a feasible choice.  相似文献   
98.
Background Because there is an increased inflammatory response to trauma, particularly of the skin, in patients with Behçet's syndrome (BS), an alteration in wound healing in BS is expected. The aim of this study was to investigate the healing features of punch biopsy wounds in BS and acne vulgaris (AV) patients used as controls.
Method Full-thickness skin punch biopsies (4 mm) were taken from the hairless sites of the non-dominant forearms in 20 BS and 20 AV patients. Each patient was examined on days 1, 2, 3, 4, 5, 8, and 10, and the biopsy wound area and induration were marked on sterile glass slides. Other inflammatory changes, such as suppuration and pain, were also recorded. No antiseptic solutions or ointment, except saline, were used.
Results The wound area healed similarly in both groups ( p > 0.05). Thirteen (65%) BS patients had erythematous haloes around the wound on the first day. The number of patients presenting inflammatory changes reached 18 (90%) on the second day in the BS group. The area of erythema around the wound in BS patients was significantly greater than that in AV patients (5; 25%). It gradually decreased day by day. Purulent changes were observed in four BS patients on day 1, and induration around the biopsy wound in six patients on day 2. Only one patient with AV had suppuration, which appeared on the second day, while no AV patient displayed induration.
Conclusion Biopsy-induced trauma may cause increased inflammation in BS, but wound healing is not altered.  相似文献   
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