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141.
Localized proton magnetic resonance spectroscopy of a cerebellar tumor in a two-year-old child 总被引:1,自引:0,他引:1
B. Wilken G. Helms H. J. Christen J. Bhnk J. Frahm F. Hanefeld 《Child's nervous system》1996,12(10):626-629
Noninvasive localized proton magnetic resonance spectroscopy (MRS) was used for differential diagnosis of a focal brain lesion in a 2.5-year-old girl. The clinical signs were a mild head tilt and neck pain. Magnetic resonance imaging (MRI) revealed a lesion in the right hemisphere of the cerebellum, but its nature remained obscure. In this lesion quantitative determinations of cerebral metabolites by fully relaxed, short-echo-time proton MRS revealed markedly lowered N-acetylaspartate (NAA) and pronounced elevations of choline-containing compounds (Cho) and myo-inositol (Ins), whereas metabolite concentrations in cortical gray matter and white matter were within normal ranges. The metabolite pattern of the lesion indicated loss of vital neuroaxonal tissue (low NAA) and enhanced glial proliferation (high Cho and Ins), which, together with the MRI morphology, suggested a brain tumor. The diagnosis was established by neurosurgical exploration and total extirpation of the tumor. Histology confirmed an astrocytoma (WHO II). After 2 weeks' recovery the child was discharged with no neurological signs. 相似文献
142.
143.
A prognosis of patients with a curative resected advanced cancer of the lower gastric region was worse than that of the other region of the stomach. The 5 year survival rate was only 47.3%. One of the main reasons was that a rate of lymph node recurrence was higher. In this point of view, we studied on lymphatic flow of the lower gastric region using an activated carbon particle (CH40). Lymph nodes were stained black soon after the injection of CH40 into the lower gastric wall at laparotomy. The black stained rate of an each regional lymph node was as follows. 3. 58%, 4. 17%, 5. 50%, 6. 25%, 1. 21%, 7. 58%, 8. 83%, 9. 58%, 11. 17% and 12. 33% in case of injection into the greater curvature and and 4. 31%, 6. 100%, 8. 25%, 9. 25%, 14V and 56% in case of injection into the lesser curvature. The stained rate was relatively high in 12 and 14V lymph node which we had not routinely dissected. The rates of lymph nodes stained black were related to those of cancer metastasis. The results suggest that lymphadenectomy of 12 for the cancer at the lesser curvature and that of 14V for the cancer at the greater curvature might make a prognosis of lower gastric cancer better. 相似文献
144.
145.
During recent decades there has been a controversial discussion if comparable plasma level profiles which are rather constant or those which show a high peak are more efficient for the cure of gonorrhoea. So far, investigations in this field were not based on the Grasso apparatus. Although the findings with cefotiam and ceftizoxime do not allow to formulate a general hypothesis without any restriction, it can be stated that on the basis of an identical area under the antibiotic level time curve, 'peak concentration' profiles are more favourable. 相似文献
146.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben. 相似文献
147.
Erythropoietin production in healthy volunteers subjected to controlled hypobaric hypoxia: further evidence against a role for adenosine 总被引:2,自引:2,他引:0
Aims Objective of this study was to investigate whether adenosine modulates renal erythropoietin production.
Methods In the present study erythropoietin production was stimulated by hypobaric hypoxia by subjecting healthy volunteers to a simulated altitude of 4000 m in a low pressure chamber for 5.5 h. During exposure to hypoxia the subjects received i.v. in a randomized, single-blind, cross-over fashion the non-specific adenosine antagonist theophylline, the adenosine reuptake inhibitor dipyridamole and placebo.
Results Contrary to the working hypothesis, theophylline did not decrease and dipyridamole did not further boost erythropoietin concentrations.
Conclusions The results are in agreement with our earlier study using haemorrhage as a controlled physiological stimulus of erythropoietin production, and would question a major role for adenosine as a mediator of renal erythropoietin production. 相似文献
Methods In the present study erythropoietin production was stimulated by hypobaric hypoxia by subjecting healthy volunteers to a simulated altitude of 4000 m in a low pressure chamber for 5.5 h. During exposure to hypoxia the subjects received i.v. in a randomized, single-blind, cross-over fashion the non-specific adenosine antagonist theophylline, the adenosine reuptake inhibitor dipyridamole and placebo.
Results Contrary to the working hypothesis, theophylline did not decrease and dipyridamole did not further boost erythropoietin concentrations.
Conclusions The results are in agreement with our earlier study using haemorrhage as a controlled physiological stimulus of erythropoietin production, and would question a major role for adenosine as a mediator of renal erythropoietin production. 相似文献
148.
STEPHEN K. DORDUNOO JAMES L. FORD MICHAEL H. RUBINSTEIN 《The Journal of pharmacy and pharmacology》1997,49(4):390-396
The effect of storage on the physical stability of solid dispersions of triamterene or temazepam in polyethylene glycols was studied using differential scanning calorimetry (DSC), particle-size analysis and dissolution methods. The enthalpies of fusion of the carriers, without included drug and previously fused and crystallized, increased on storage. Analysis of similarly treated solid dispersions, containing either 10% temazepam or 10% triamterene, showed that each drug influenced the morphology of the polyethylene glycol (PEG). The enthalpies and melting points of the solidus components of the dispersions' carriers were initially reduced after preparation, but on storage these increased. The particle sizes of the drugs dispersed in the PEGs increased on storage. The changes in dissolution after storage of triamterene or temazepam dispersions were smaller for dispersions in PEG 1500 than for dispersions in PEGs of higher molecular weight (PEG 2000, PEG 4000 or PEG 6000) in which the reduction in dissolution was particularly marked during the first month of storage. The rank order of changes in dissolution were PEG 1500 ? PEG 2000 < PEG 4000 ~ PEG 6000. 相似文献
149.
Tayama K; Takamori S; Mitsuoka M; Hiraki H; Ohtsuka S; Hayashi A; Aoyama Y; Shirouzu K 《Japanese journal of clinical oncology》1997,27(6):401-405
The aim of this study was to investigate retrospectively the efficacy of
expandable metallic stents (EMSs) for severe respiratory distress in
patients with central airway obstruction. Twenty patients with central
airway obstructions were treated with an EMS. An intraluminal stricture was
present in 15 and an extraluminal stricture in 5 patients. Of the 15
patients with intraluminal stenosis, 11 exhibited symptomatic improvement.
All 11 patients had tumor infiltration occupying less than 50% of the
endoluminal diameter. The other four patients with intraluminal stenosis
had tumor infiltration occupying > 50% of the endoluminal diameter and
demonstrated no improvement. All five patients with extraluminal stenosis
were improved. EMS is useful for an extraluminal stricture in the central
airway and the effect of EMS for intraluminal stenosis is related to the
degree of infiltration and of tumor progression itself.
相似文献
150.
H. Nilsson J. Johansson K. Svanberg S. Svanberg G. Jori E. Reddi A. Segalla D. Gust A. L. Moore T. A. Moore 《British journal of cancer》1997,76(3):355-364
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated. 相似文献