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11.
OBJECTIVE: The purpose of this study was to correlate 18F-fluorodeoxyglucose positron emission tomography (PET) and MR imaging features of cerebral gangliogliomas before and after PET-MR image registration. CONCLUSION: After registration of PET and MR images, all six gangliogliomas in our series were shown to have heterogeneous metabolic activity. Areas of hypermetabolic activity were seen in all lesions. In five of the six cases, PET-MR image registration provided information regarding tumor metabolism that was not available on nonregistered hard-copy examinations.  相似文献   
12.
In chronic empyema (CE), thickened pleura, collapsed chest wall, and the accumulation of purulent fluid in the thoracic cavity are typical findings. Patients complaints of symptoms with bronchopleural fistula (BPF). On the other hand, there is another type of CE in which the pleural space expands progressively to shift the neighboring lungs, mediastinum, and diaphragm. This type of CE is considered to be chronic expanding hematoma (Reid et al.) occurring in the thoracic cavity. In the empyemic cavity, mycobacterial infection is found approximately in 20-30% of cases, pyogenic bacillus or fungus in about 40%, but the cavity is aseptic in other 30-40%. Although the fundamental treatment procedures include decortication and pleuropneumonectomy, the method of muscle or omental plombage to manage dead space or BPF are far superior functionally in intractable CE. Recently, the methods of plastic and reconstructive surgery have been used to utilize the muscle or omentum more effectively. The classic thoracoplasty procedure should not be undertaken unnecessarily to avoid additional deterioration of respiratory function. Additionally, it should be remembered that malignant lymphoma occurs frequently in the empyemic chest wall.  相似文献   
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Summary  The diagnosis of tethered cord syndrome (TCS) without typical conus medullaris symptoms and the radiological features such as a low set conus medullaris or dysraphic malformation is difficult. We report 11 year old identical twin brothers with TCS associated with the conus at the normal level. Their presenting symptom was progressive leg pain and both patients underwent surgical interruption of the filum terminale. The pain recurred in one patient treated surgically only after symptom became worse but resolved immediately in the other sibling treated promptly. We indicate the importance of early diagnosis and treatment of TCS to obtain excellent long-term outcome despite the absence of a low set conus or specific symptoms. Furthermore, when a twin or sibling of an affected person has neurological symptoms and the cutaneous signature of spinal dysraphism, radiological examination should be performed to establish the cause.  相似文献   
15.
  • 1) The prolidase (Pd) and prolinase (Pn) activities of cultured skin fibroblasts derived from two prolidase-deficient sisters, the elder with typical clinical manifestations [symptom (+)] and the younger with only slight clinical manifestations [symptom (–)] were examined biochemically. Pd activity against several substrates other than Gly-Pro were present to some degree in both sisters. There were no detectable differences in Pd activity between the symptom (+) patient and the symptom (–) sister. Pn activity seemed to be increased in both. The lower Pn activity found against Pro-Gly as compared with those against other substrates indicates that Pro-Gly, which has been used for Pn assays in most previous reports, may not be the best substrate for this test. Pd derived from control fibroblasts was activated by Mn2+ against all substrates tested in this experiment. Cu2+, Hg2+, Cd2+ and Zn2+ remarkably inhibited enzyme activity, Co2+ slightly inhibited it, and neither Mg2+ nor Fe2+ had any remarkable effect. The Pd derived from the prolidase-deficient patients was also activated by Mn2+. This Pd seemed to be more inhibited by Co2+ than was the control. However, we found no remarkable differences between the two patients.
  • 2) We also studied Pd and Pn activities in rat skin and blood during wound healing. Pd and Pn activities adjacent to the wound increased in parallel with fibroblast proliferation. Pd activity was also detected in an extract of newborn mouse epidermis.
  相似文献   
16.
We report the use of topical application of recombinant human basic fibroblast growth factor (rhbFGF) to successfully treat therapy-resistant, chronic leg ulcers in scleroderma. Endothelial cell FGF receptors are directly stimulated by bFGF; also, bFGF promotes the regeneration of capillary-rich granulation tissue. We conclude that topical bFGF may be a powerful new pharmacologic tool for treating severe skin ulcers.  相似文献   
17.
BACKGROUND: There are few monitoring systems widely used in clinical practice for evaluating the effectiveness of aspirin therapy, so in the present study aspirin's antiplatelet effects we investigated with a whole blood aggregometer using a screen filtration pressure (SFP) method. METHODS AND RESULTS: Thirty-five healthy male volunteers took 100 mg/day aspirin for 14 days. Whole-blood aggregation was analyzed at baseline and on days 7 and 14, using collagen and adenosine diphosphate as the stimuli, and compared with the platelet-rich plasma (PRP) aggregation measured by optical aggregometer. The platelet-aggregation threshold index (PATI) for both methods, which was defined as the putative agonist-concentration giving half-maximal aggregation, and the PRP-maximal aggregation rate were analyzed. The maximal aggregation rate induced by 1.6 mg/L collagen decreased from 85.5% (80.8-92.8) [median (interquartile range)] at baseline to 51.5% (39-63.8) on day 14 (p<0.0001). The PRP-PATI and whole-blood PATI for collagen increased from 0.32 (0.28-0.70) to 1.82 mg/L (1.25-2.89) (p<0.0001) and from 0.28 (0.22-0.3) to 1.06 mg/L (1.01-1.29) (p<0.0001) respectively. CONCLUSIONS: The whole-blood PATI and PRP-PATI for collagen, as well as the maximal PRP aggregation rate, clearly distinguish platelet aggregability before and after aspirin intake. However, whole-blood analysis by the SFP-method is easier to perform, and is a promising method of monitoring aspirin's effects.  相似文献   
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Polyamines (PAs) are ubiquitous, polycationic compounds that are essential for the growth and survival of all organisms. Although the PA-uptake system plays a key role in mammalian cancer and in plant survival, the underlying molecular mechanisms are not well understood. Here, we identified an Arabidopsis L-type amino acid transporter (LAT) family transporter, named RMV1 (resistant to methyl viologen 1), responsible for uptake of PA and its analog paraquat (PQ). The natural variation in PQ tolerance was determined in 22 Arabidopsis thaliana accessions based on the polymorphic variation of RMV1. An RMV1-GFP fusion protein localized to the plasma membrane in transformed cells. The Arabidopsis rmv1 mutant was highly resistant to PQ because of the reduction of PQ uptake activity. Uptake studies indicated that RMV1 mediates proton gradient-driven PQ transport. RMV1 overexpressing plants were hypersensitive to PA and PQ and showed elevated PA/PQ uptake activity, supporting the notion that PQ enters plant cells via a carrier system that inherently functions in PA transport. Furthermore, we demonstrated that polymorphic variation in RMV1 controls PA/PQ uptake activity. Our identification of a molecular entity for PA/PQ uptake and sensitivity provides an important clue for our understanding of the mechanism and biological significance of PA uptake.  相似文献   
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