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991.
Krause I He XS Gershwin ME Shoenfeld Y 《Journal of autism and developmental disorders》2002,32(4):337-345
Pervasive developmental disorders represent a group of neurodevelopmental disorders that affect children early in their development. Autistic disorder is the best described of these disorders, yet even this term covers a broad group of clinical presentations. Various immune system abnormalities, including autoimmunity and defects in different subsets of immune cells, have been reported in children with autistic disorder, suggesting that immune factors may play a role in the development of autism. Based on anecdotal observation, vaccination was proposed to cause autism in some children, but several controlled studies have failed to support this claim. Intravenous immunoglobulin infusions has been tested as immunotherapy for autism, although the preliminary results are inconclusive and there is a risk of potentially fatal transmission of blood-borne pathogens. To examine this issue, intensive well-controlled epidemiological and bench studies need to be carried out in defined and carefully controlled study subjects to establish the cellular and molecular basis of autism, against which the effects of each proposed immune factor can be examined. 相似文献
992.
Are peripheral blood cells from patients with Alzheimer disease more sensitive to apoptotic stimuli?
Bergman M Salman H Beloosesky Y Djaldetti M Bessler H 《Alzheimer disease and associated disorders》2002,16(3):156-160
One of the reasons for the increased susceptibility to infections in patients with Alzheimer disease may be enhanced apoptotic death of their peripheral leukocytes. If this is the case, the enhanced apoptosis may be due to components in the patients' sera or to an increased sensitivity of the cells to apoptotic stimuli. To examine this possibility, the percentage of apoptotic cells in the peripheral blood mononuclear cells (PBMC) from 12 patients with Alzheimer disease was compared with that of 12 age-matched non-demented persons and 12 middle-aged healthy control subjects. In addition, the effect of sera from subjects in the three groups on the apoptosis, interleukin (IL)-1beta, IL-2, IL-6, IL-10, and tumor necrosis factor (TNF)alpha production by peripheral blood cells from healthy control subjects was examined. It was found that the percentage of apoptotic PBMC from patients with Alzheimer disease was higher than that from the remaining two groups. However, incubation of control cells with sera from patients with Alzheimer disease and non-demented elderly persons did not affect the number of apoptotic cells. Sera from patients with Alzheimer disease and non-demented elderly subjects caused an increase in IL-2 and a decrease in IL-10 production by PBMC from middle-aged control subjects but did not affect IL-1beta, IL-6, and TNFalpha secretion, indicating alterations of the immune system related to aging. 相似文献
993.
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995.
Shupak A Arieli Y Bitterman H Brod V Arieli R Rosenhause G 《Ultrasound in medicine & biology》2002,28(5):655-660
High-frequency sound might cause bubble enlargement by rectified diffusion. The purpose of the present study was to investigate gas bubble formation in the immersed diving animal during exposure to high-frequency sound. Anaesthetised rats were subjected to a simulated diving profile while immersed inside a hyperbaric chamber. An acoustic beacon (pinger) was placed ventral to the animal's abdomen, transmitting at an intensity of 208.9 dB re 1 micro Pa and a frequency of 37 kHz. Six groups of eight animals were included in the study as in Table 1, breathing air (n = 4) or Nitrox 72/28 (n = 2), at a depth of 0 m, 30 m or 40 m. Immediately after decompression, the intestinal mesenterium was imaged, and frames were acquired digitally. The number of bubbles and their radii were analysed and compared among the groups. The mean bubble density for group 1 was 1.35 +/- 0.18 bubbles/mm(2), significantly higher when compared with the other groups (p < 0.0001). The average bubble radius for groups 1 and 2 was similar (12.57 +/- 4.1 and 10.63 +/- 1.8 microm, respectively), but significantly larger than in the other groups (p < 0.0002). The percentage of bubbles with a radius greater than 50 microm was significantly higher in group 1 (p < 0.0001). The results suggest that commercially available underwater pingers might enhance bubble growth during deep air diving. 相似文献
996.
997.
Burning mouth syndrome 总被引:6,自引:0,他引:6
Burning mouth syndrome is characterized by a burning sensation in the tongue or other oral sites, usually in the absence of clinical and laboratory findings. Affected patients often present with multiple oral complaints, including burning, dryness and taste alterations. Burning mouth complaints are reported more often in women, especially after menopause. Typically, patients awaken without pain but note increasing symptoms through the day and into the evening. Conditions that have been reported in association with burning mouth syndrome include chronic anxiety or depression, various nutritional deficiencies, type 2 diabetes (formerly known as non-insulin-dependent diabetes) and changes in salivary function. However, these conditions have not been consistently linked with the syndrome, and their treatment has had little impact on burning mouth symptoms. Recent studies have pointed to dysfunction of several cranial nerves associated with taste sensation as a possible cause of burning mouth syndrome. Given in low dosages, benzodiazepines, tricyclic antidepressants or anticonvulsants may be effective in patients with burning mouth syndrome. Topical capsaicin has been used in some patients. 相似文献
998.
The histologic spectrum of epidermodysplasia verruciformis in transplant and AIDS patients 总被引:2,自引:0,他引:2
BACKGROUND: The purpose of this study was to correlate the histologic findings of skin lesions clinically suspicious for epidermodysplasia verruciformis with the viral findings in patients with organ transplants or AIDS. METHODS: Thirty-seven skin biopsies from 17 patients (six with AIDS and 11 with transplants) were studied as a non-randomized, controlled, unblinded case series by in situ hybridization for HPV DNA. RESULTS: Nineteen (51%) of these biopsies were HPV-positive by in situ hybridization either for HPV type 5 (five cases), type 8 (10 cases), type 16 (four cases) or HPV 31 (one case, with one case of dual infection). Only eight of the 19 HPV-positive tissues (42%) showed the classic histologic features of verruca planae. The more common histologic feature significantly associated with HPV detection was a focally thickened and disrupted granular layer (13/19 [68%] vs. 8/18 [44%], p < 0.04). Dysplasia was evident in 12/19 HPV-positive tissues (63%), which was significantly greater than in patients with congenital epidermodysplasia verruciformis (20%). CONCLUSIONS: Oncogenic HPV types are detected in about one-half of skin biopsies from immunocompromised patients with a clinical presentation suspicious for epidermodysplasia verruciformis. Many of these lesions lack the histologic features of verruca planae, a focally thickened granular layer is a marker for viral detection, and the risk for dysplasia in such lesions is much higher than in epidermodysplasia verruciformis not associated with acquired immunosuppression. 相似文献
999.
Kellner M Yehuda R Arlt J Wiedemann K 《Acta psychiatrica Scandinavica》2002,105(2):153-5; discussion 155-6
OBJECTIVE: In chronic post-traumatic stress disorder (PTSD) lowered cortisol secretion and hypersuppression to dexamethasone has been described repeatedly. However, so far no longitudinal data on the natural course or on the effect of therapy are available. METHOD: We measured basal and post-dexamethasone morning salivary cortisol in a drug-free patient with chronic PTSD (DSM-IV) monthly for nearly 2 years and assessed PTSD and depressive symptoms. RESULTS: Salivary cortisol decreased dramatically 3 months after the traumatic event and in the further course showed an inverse relation to fluctuating but gradually improving PTSD symptoms. Post-dexa-methasone cortisol was suppressed below the detection limit early after trauma and rose again more than 1 year post-trauma. CONCLUSION: Both the potential renormalization of low cortisol levels in improving chronic PTSD and the putative vulnerability to develop PTSD in subjects with increased dexamethasone suppression need further research. 相似文献
1000.
Golier JA Yehuda R Lupien SJ Harvey PD Grossman R Elkin A 《The American journal of psychiatry》2002,159(10):1682-1688
OBJECTIVE: The authors evaluated memory performance in Holocaust survivors and its association with posttraumatic stress disorder (PTSD) and age. METHOD: Memory performance was measured in Holocaust survivors with PTSD (N=31) and without PTSD (N=16) and healthy Jewish adults not exposed to the Holocaust (N=35). Explicit and implicit memory were measured by paired-associate recall and word stem completion, respectively. RESULTS: The groups did not differ by age or gender, but the survivors with PTSD had significantly fewer years of education and had lower estimated IQs than the survivors without PTSD and the nonexposed group. There was a significant overall group effect for paired-associate recall but not word stem completion. The survivors with PTSD recalled fewer semantically unrelated words than did the survivors without PTSD and the nonexposed group and fewer semantically related words than the nonexposed group. Of the survivors with PTSD, 36% performed at a level indicative of frank cognitive impairment. Older age was significantly associated with poorer paired-associate recall in the survivors with PTSD but not in the other two groups. CONCLUSIONS: Markedly poorer explicit but not implicit memory was found in Holocaust survivors with PTSD, which may be a consequence of or a risk factor for chronic PTSD. Accelerated memory decline is one of several explanations for the significantly greater association of older age with poorer explicit memory in survivors with PTSD, which, if present, could increase the cognitive burden of this illness with aging. 相似文献