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21.
Five cases of cerebral glioma are presented here that illustrate the benefit of functional CT imaging of blood-brain barrier permeability and cerebral blood volume. Functional CT uses Patlak analysis of a single location dynamic sequence to extract physiological information that is useful clinically in the assessment of cerebral gliomas. Functional CT offers distinct advantages over other functional modalities including clearer delineation of tumour, tumour grading, measurement of tumour activity and monitoring response to therapy.  相似文献   
22.
The incidence and importance of retained placenta (RP) varies greatly around the world. In less developed countries, it affects about 0.1% of deliveries but has up to 10% case fatality rate. In more developed countries, it is more common (about 3% of vaginal deliveries) but very rarely associated with mortality. There are three main types of retained placenta following the vagina delivery: placenta adherens (when there is failed contraction of the myometrium behind the placenta), trapped placenta (a detached placenta trapped behind a closed cervix) and partial accreta (when there is a small area of accreta preventing detachment). All can be treated by manual removal of placenta, which should be carried out at 30-60 minutes postpartum. Medical management is also an option for placenta adherens and trapped placenta. The need for manual removal can be reduced by 20% by the use of intraumbilical oxytocin (30 i.u. in 30 mL saline). A trapped placenta may respond to glyceryl trinitrate (500 mcg sublingually) or gentle, persistent, controlled cord traction.  相似文献   
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<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
24.
1. The metabolic fate of the model ecotoxin 3-trifluoromethylaniline (3-TFMA) in earthworm was studied by 19 F- and directly coupled 19 F/ 1 H-HPLC-NMR spectroscopy. Earthworms of Eisenia veneta spp. were subjected to the ecotoxin during a filter papercontact toxicity test at exposure levels of 1000, 100, 10, 1 and 0.1 µg cm -2. A metabolic profile was obtained previously by 19 F-NMR spectroscopy and metabolites were observed at all the exposure levels. 2. Identification of metabolites in individual worm extracts at the (lethal) exposure levels of 1000 and 100 µg cm -2 could be achieved on-line without sample preparation by 19 F/ 1 H-HPLC-NMR spectroscopy. 19 F-HPLC-NMR spectroscopy was used in the continuous-flow mode, which enabled the HPLC chromatographic retention times (t R) of the metabolites to be established in a single analytical step. 3. In total, three 19 F-NMR signals could be detected, of which one was identified as the parent compound. Two earlier eluting metabolites were identified to be α - and β -glucoside conjugates of 3-TFMA. 4. Metabolites at the lower (sublethal) exposure levels of 10, 1 and 0.1 µg cm -2 escaped identification by 19 F/ 1 H-HPLC-NMR spectroscopy as outlined here and will require concentration prior to analysis.  相似文献   
25.
Homans  AC; Forman  EN; Barker  BE 《Blood》1985,66(6):1321-1325
The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL.  相似文献   
26.
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition. Electronic Publication  相似文献   
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Management of chronic lunotriquetral ligament tears   总被引:1,自引:0,他引:1  
Treatment of chronic disruptions of the lunotriquetral (LT) ligament is not well-defined. Eleven patients treated by LT fusion with use of a compression screw are reported. The injury frequently resulted from hyperextension of the wrist. Pain on the ulnar side of the wrist, limited motion, and tenderness over the LT joint exacerbated by ballottement were present. Standard radiographs were normal. Arthrography showed the ligamentous tear in all cases. After operation, immobilization was continued until fusion was apparent radiographically. Fusion was achieved in all cases between 2 and 5 months. Four patients were free of pain, four patients had pain only at the extremes of motion, and three patients had persistent pain. Mean wrist motion was as follows (preoperative/postoperative): flexion (53 degrees/45 degrees), extension (60 degrees/49 degrees), radial deviation (17 degrees/21 degrees), and ulnar deviation (25 degrees/18 degrees). Maximum grip strength as a percentage of the uninjured side was 73% preoperatively and 59% postoperatively. LT tears can exist de novo or as part of the ulnar impaction syndrome; a method for differentiation is presented.  相似文献   
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