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91.
To evaluate whether frank or subtle disorders of adrenal steroidogenesis exist in human immunodeficiency virus (HIV)-infected children, the adrenal steroid response to an iv bolus of ACTH-(1-24) (0.25 mg Cortrosyn) was determined. Ten children (six males and four females, aged 7 months to 7.5 yr) were studied. Five underwent repeat testing 3-5 months after initial assessment. Nine patients were classified as P2 or symptomatic according to the Center for Disease Control criteria for HIV infection in children. Eight had failure to thrive, six had opportunistic infections and neurological deficits, and two were receiving ketoconazole at the time of ACTH testing. Only one patient had a neonatally acquired transfusion-related HIV infection. Three of the children died 2-5 months after ACTH testing. All patients had normal or slightly elevated baseline and stimulated cortisol levels compared to the control population. The mean post-ACTH cortisol level was significantly higher than the mean post-ACTH level in the control population. No patient demonstrated an impaired aldosterone response to ACTH. The basal and ACTH-stimulated dehydroepiandrosterone levels were normal. Although individual deoxycorticosterone and corticosterone levels were variable, the mean stimulated deoxycorticosterone and corticosterone levels in the patients were suggestive of a selective defect of the 17-desoxy pathway in the adrenal fasciculata. No changes were noted in the patients' cortisol, dehydroepiandrosterone, and aldosterone responses on repeat ACTH testing. In HIV-infected children we have demonstrated that cortisol and aldosterone synthesis is intact. Thus, the chronic debilitation observed cannot be explained on the basis of adrenal insufficiency. However, a selective deficiency of 17-desoxysteroid hormone production from the adrenal fasciculata may be present.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
92.
Spinal cord dysfunction is a rare complication of Neisseria meningitidis (meningococcal) meningitis. We report a 17-year-old patient who had a 3-day history of fever, headache and vomiting, agitation, and unresponsiveness. Cerebrospinal fluid showed a marked polymorphonuclear pleocytosis. Latex particle agglutination was positive for meningococci. The patient was given intravenous antibiotics and intravenous dexamethasone. Over the next 4 days, he developed weakness of the lower extremities, with areflexia and extensor plantar responses. MRI revealed contiguous hyperintensities on T2-weighted images involving the thoracic spinal cord from T4 to T9 and 4 brain abscesses. Five months later, he recovered brain function, but the paraparesis remained. This case illustrates that myelopathy may complicate acute meningococcal meningitis, possibly due to a vasculitis, stroke, autoimmune myelopathy, or direct infection of the spinal cord. Patients with myelopathy associated with acute meningitis should receive spinal MRI. In addition, meningitis should be considered in patients presenting with acute myelopathy.  相似文献   
93.

Purpose

The purpose of this study was to compare enhancement characteristics of half-dose gadobenate dimeglumine (0.05 mmol kg?1) with standard-dose gadodiamide (0.10 mmol kg?1), in the assessment of hepatic vessels and lesions, using retrospective intra-individual crossover comparison methodology.

Methods

Ethics committee approval was obtained. From 2004 to 2012, 21 patients underwent MRI examination with both standard-dose gadodiamide and half-dose gadobenate dimeglumine, using the same liver MRI protocol at 1.5 T. Eighteen patients whose scans showed no artifacts were selected. Quality of liver lesion [12 hemangiomas, 7 focal nodular hyperplasias (FNHs)] and liver vessel enhancement, and the global diagnostic quality of studies were ranked on a scale of 1–4 by two independent radiologists. Contrast-to-noise ratio (CNR) and % enhancement of liver vessels and lesions were calculated based on region of interest, signal intensity, and noise standard deviation measurements performed at 0, 20 s, 1, 3, and 5 min post-contrast injection. Qualitative and quantitative results were compared using the paired Wilcoxon signed rank and Student’s t-tests, respectively.

Results

No qualitative differences were noted in enhancement of liver vessels, hemangiomas, and FNHs. There was no statistically significant difference between the global diagnostic qualities of scans performed with the two contrast agents. Quantitatively, liver vessels and hemangiomas did not demonstrate statistically significant differences in contrast enhancement. At 20 s, FNHs achieved higher CNR (P = 0.02) with gadodiamide.

Conclusion

Half-dose gadobenate dimeglumine results in similar contrast enhancement compared to standard-dose gadodiamide in assessment of liver vessels, hemangiomas, and FNHs, and is a reasonable alternative to standard doses of extracellular agents in dynamic liver MRI.  相似文献   
94.
Abstract MRI may be helpful in showing brain toxicity associated with chronic toluene inhalation. We report clinical and MRI findings over 3 years in a man with gradual neurologic decline secondary to toluene abuse. Cerebral atrophy most prominently involved the corpus callosum and cerebellar vermis. On T2-weighted images, loss of gray-white matter contrast, diffuse supratentorial white matter high-signal lesions, and low signal in the basal ganglia and midbrain were seen. In addition, MRI showed abnormal labor cortical low signal on T2-weighted images, most prominent in the primary motor and visual cortex. This cortical T2 shortening, not previously described in this condition, may reflect iron deposition. Received: 14 October 1997 Accepted: 18 December 1997  相似文献   
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96.
Summary We have compared single oral doses of drinkable diclofenac dispersible (50 mg) with ibuprofen (400 mg) and placebo in a randomized, double-blind, parallel-group trial in 127 adults complaining of at least moderately severe pain after removal of an impacted third molar. Within 40 min both diclofenac and ibuprofen produced significant pain relief that persisted for 6 h. There were no differences between diclofenac and ibuprofen in analgesic efficacy.  相似文献   
97.
To evaluate the clinical significance of 99mTc-sulfur-colloid (TcSC) spleen scan findings in patients with malignant melanoma, a retrospective study was undertaken. Eighty-one patients with histologically proven malignant melanoma who received treatment in Roswell Park during a five-year period were included in this study. The scans were analyzed for spleen size, differential uptake of the tracer in liver and spleen, and for the presence of metastases in these two organs. These data were compared with stage of disease, survival, and autopsy findings. Significant correlation was found between the splenic size as measured on the scintiscan and at autopsy examination. The spleen size was found to be normal in 92% of the patients in early melanoma. The median survival of patients who had a normal-sized spleen by scan criteria was found to be longer than those who had splenomegaly. No significant difference in survival was noted between the patients with and without augmented splenic uptake of TcSC. Only a small number (17.7%) of patients with augmented splenic uptake had splenic metastases; hence, the possible role of immunological factors was considered.  相似文献   
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R Bakshi  R X Ni  A I Faden 《Brain research》1992,580(1-2):255-264
Both N-methyl-D-aspartate (NMDA) and opioid receptors have been implicated in the pathophysiology of traumatic spinal cord injury and dynorphin-induced paralysis. The present studies compared the effects of the non-competitive NMDA antagonist dextrorphan (Dex) and the kappa-selective opioid antagonist nor-binaltorphimine (nor-BNI) on the acute motor deficits and chronic neuropathological alterations caused by intrathecally administered dynorphin A-(1-17) (Dyn A). Infusion of Dyn A into the rat lower thoracic spinal subarachnoid space produced acute, reversible hindlimb paresis. Histological evaluations of spinal cord sections from these animals at 2 weeks post-infusion revealed ventral grey matter necrosis, neuronal loss and gliosis as well as axonal loss in adjacent white matter; however, there was minimal alteration in serotonin immunocytochemistry caudal to the injury zone. Dex or non-BNI pretreatment each significantly (P less than 0.05) reduced, and to a similar degree, the acute motor deficits and certain histological changes associated with Dyn A administration. These findings further support the hypothesis that dynorphin-induced spinal cord injury involves both NMDA receptors and opioid receptors.  相似文献   
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