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81.
Late-presenting congenital diaphragmatic hernia (CDH) is often difficult to diagnose and delay in treatment is common. Seven patients were operated beyond the newborn period for left-sided Bochdaleck hernia. Their age ranged from 1 month to 9 years. Six of them became symptomatic within the 1st year of life (1 week to 9 months of age). Either feeding difficulties or recurrent respiratory infections were initially present. In all of them chest X-rays were performed but delay in diagnosis ranged from 1 week to 5 years. All diaphragmatic defects could be closed by an abdominal approach without postoperative complications. Clinical symptoms disappeared postoperatively. In children with respiratory complaints or feeding difficulties one should be aware of late presenting CDH. A careful analysis of chest films and searching for connecting bowel segments passing through the diaphragmatic defect may help to avoid incorrect diagnosis and undesirable delay in treatment. Confusion with pneumonia or pneumothorax can be diminished by placing a feeding tube and instillation of contrast material. Ultrasound should be used supportively in all suspected diseases of the diaphragm. 相似文献
82.
A. Spallone 《Acta neurochirurgica》1981,58(1-2):75-84
Summary A nine-year-old boy, presenting only with signs of increased ICP, underwent computerized tomography. This examination demonstrated no abnormalities in the precontrast scan. Following C. E., it showed scattered areas of blood-like density in both hemispheres, as well as a presumedly abnormal vessel in the left occipital region and dilated vein of Galen, sinus rectus, and tentorial veins. The presumptive diagnosis of left occipital AVM was not confirmed by angiography, which also ruled out obstructions of the intracranial sinuses.The possible mechanism responsible for this atypical CT picture is briefly discussed in the light of pertinent literature. It is suggested that careful consideration should be given to the indications for angiography in similar cases, in the presence of a hypervascular aspect of the postcontrast CT scan, particularly if a considerable amount of contrast medium has been used. 相似文献
83.
C G Lipinski 《Epilepsia》1977,18(1):13-20
In 17 patients with a long course of epilepsy astatic seizures became apparent after the age of 14 years. In the patients' childhood astatic seizures had not been observed. The patients suffered from epilepsies with absences and awakening grand mal or psychomotor fits and sleeping grand mal. The EEG revealed spike-wave variant and spike-and-wave complexes as in the Lennox-Gastaut syndrome. Age dependency of Lennox-Gastaut syndrome is discussed. The described type of epilepsy can be understood as a "Lennox-Gastaut syndrome of late onset". 相似文献
84.
Green Philip G. Hinz Robert S. Kim Aeri Szoka Francis C. Guy Richard H. 《Pharmaceutical research》1991,8(9):1121-1127
The iontophoresis of eight tripeptides, of the general structure alanine–X–alanine, has been measured across hairless mouse skin in vitro. The peptides were blocked (a) at the carboxyl terminus using the mixed anhydride reaction with t-butylamine and (b) at the amino terminus by acetylation with 14C-acetic anhydride. The nature of the central residue (X) was varied by selecting one of five neutral amino acids, two negatively chargeable moieties (aspartic and glutamic acids), and a positively chargeable species (histidine). Constant current iontophoresis at 0.36 mA/cm2, using Ag/AgCl electrodes, was performed for 24 hr in diffusion cells, which allowed both anode and cathode to be situated on the same (epidermal) side of a single piece of skin. Due to a combination of osmotic and electroosmotic forces, the anodal iontophoretic flux of neutral peptides was significantly greater than passive transport. Steady-state fluxes were not achieved, however, suggesting that time-dependent changes in the properties of the skin barrier may be occurring. Limited, further experiments confirmed that, on a 24-hr time scale, these changes were not fully reversible. The cathodal delivery of anionic permeants was well controlled at a steady and highly enhanced rate by the current flow. This behavior closely paralleled earlier work using simple negatively charged amino acids and N-acetylated amino acid derivatives. It appears that the normalized iontophoretic flux of these anionic species is independent of lipophilicity but may be inversely related to molecular weight. The positively charged peptide, Ac–Ala–His–Ala–NH(But), showed greater anodal iontophoretic enhancement when delivered from a donor solution at pH 4.0 than from a solution at pH 7.4. This was consistent with (a) the corresponding behavior of histidine alone and (b) the existence of a pK
a for these compounds at 6. Steady-state delivery was not achieved, although the levels of enhancement, especially at pH 4, were the largest observed. A preliminary investigation of tripeptide stability to either (i) electrolysis in the donor compartment or (ii) cutaneous metabolism revealed very little degradation under the conditions of the experiment. Overall, this research supports the principle of enhanced peptide delivery across the skin by iontophoresis and indicates a number of areas (e.g., mechanism and extent of current-induced changes in skin barrier function, molecular size dependence, pathways of current flow) on which further work should be focused. 相似文献
85.
Thirty-eight subjects who met criteria for the DSM-III-R diagnosis late luteal phase dysphoric disorder (LLPDD) were compared with 18 controls in 5-HT uptake kinetics of the platelets in the premenstrual (day 26) as well as in the postmenstrual phase (day 4) of the cycle. Furthermore, 5-hydroxytryptophan (5-HTP) was administered to LLPDD patients and controls in both phases of the cycle, to investigate pituitary sensitivity for serotonin. Plasma samples for the measurement of cortisol and -endorphin were taken before and after oral administration of 200 mg 5-HTP, and considered as an index of pituitary-adrenal function. LLPDD was not associated with a lower platelet 5-HT uptake and content in the premenstrual phase of the cycle, compared with the postmenstrual phase. Patients appeared not to be different from controls in 5-HT uptake kinetics of platelets in the premenstrual phase of the cycle. No main differences were observed between LLPDD patients and controls in their ability to respond with secretion of cortisol and -endorphin to 5-HTP stimulation, either in the premenstrual, or in the postmenstrual phase. This observation could not be attributed to differences in 5-HTP metabolism. The findings of the present study do not support a specific role for 5-HT in the pathophysiology LLPDD. 相似文献
86.
Summary Information obtained from CT scan after contrast administration was evaluated in 59 consecutive stroke patients. CT scans before and after contrast administration were performed 3 days and 21/2 weeks after stroke. A plain CT scan was repeated 6 months later. Contrast enhancement was practically not seen on the first examination, but was seen in 46% on the second examination. There was a close relationship between the occurrence of contrast enhancement and the socalled fogging effect. Contrast scanning gave additional information only when this effect was present. Plain CT scans 3 days after stroke were superior to contrast scans taken at any time for detecting and visualizing cerebral infarcts. 相似文献
87.
Contrast enhancement of the cerebrospinal fluid on MRI in two cases of spirochaetal meningitis 总被引:5,自引:0,他引:5
We report two patients with meningitis due to spirochaetal infection, both of whom showed diffusely enhancing meninges around
the brain and spinal cord. In addition, there was enhancement of the cerebrospinal fluid after intravenous administration
of Gd-DTPA.
Received: 1 March 1998/Accepted: 21 August 1999 相似文献
88.
89.
90.
Radioenhancement by cisplatin with accelerated fractionated radiotherapy in a human tumour xenograft
Joschko Marion A. Webster Lorraine K. Bishop James F. Groves Janice Yuen Kally Olver Ian N. Narayan Kailash N. Ball David L. 《Cancer chemotherapy and pharmacology》1997,40(6):534-539
The aim of the present study was to investigate whether cisplatin would enhance the radioresponse of a human tumour xenograft
when given in different schedules combined with accelerated fractionated radiation therapy. A human squamous carcinoma of
the hypopharynx, FaDu, was grown in the thigh of athymic nude mice. Tumours were exposed to twice-daily 2-Gy fractions, applied
6 h apart over 2 weeks, 5 days a week, alone or combined with cisplatin given at maximally tolerated doses in three different
schedules: (1) i.p. as a single bolus (SB) or (2) i.p. as a daily bolus at 30 min before the first daily radiation fraction
or (3) s.c. as a continuous infusion through a mini-osmotic pump over 13 days, commencing 24 h prior to the first daily radiation
fraction. The end point for the study was tumour growth delay (TGD), calculated as the difference between the delay in regrowth
to 200% of the initial tumour size in treated versus control mice. SB cisplatin plus radiation showed only an additive effect
on TGD, whereas daily-bolus and continuous-infusion cisplatin demonstrated a greater than additive effect when combined with
accelerated fractionated radiation in this human tumour model. Cisplatin appears to be especially beneficial as a radiation
enhancer when given throughout the course of radiation.
Received: 15 December 1996 / Accepted: 25 March 1997 相似文献