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41.
Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.  相似文献   
42.
A double-blind random-ordered comparison of the effects of placebo and 5-hydroxytryptophan (200 mg, orally) in ten depressed patients with seasonal affective disorder (SAD) and ten controls disclosed slightly but significantly higher basal levels of serum prolactin and a trend toward higher basal levels of serum cortisol in the patients with SAD compared with controls. After administration of 5-HTP, the cortisol level significantly increased and the prolactin level significantly decreased in both patients and controls. No differences in the melatonin level, growth hormone level, blood pressure, or pulse rate and no side effects were noted between patients and controls in the two study conditions; the timing of basal and 5-hydroxytryptophan-stimulated hormonal secretions was similar for both groups. These results are discussed with reference to current hypotheses of the cause of SAD.  相似文献   
43.
A monoclonal anti-testicular carcinoma antibody was obtained via the somatic cell fusion technique by immunization of BALB/c mice with freshly prepared single cell suspension from a patient with testicular embryonal carcinoma with choriocarcinoma components. The hybridoma supernates were screened against the testicular carcinoma cells used in the immunization as well as normal mononuclear white blood cells isolated from the same patient. An antibody (5F9) was selected which bound to fresh tumor cells from two patients with embryonal testicular carcinoma and failed to bind to fresh tumor cells from 24 patients (2 seminoma, 2 melanoma, 3 neck, 2 esophageal, 1 ovarian, 3 colon, 1 prostate, 2 breast, 1 liposarcoma, 3 endometrial, 1 kidney, 1 adrenal, 1 larynx and 1 bladder tumors) or cell suspensions prepared from normal liver, lung, spleen, ovary, testes, kidney, red blood cells or white blood cells. The antibody was tested for its binding to several well established cancer cell lines, and was found to bind to the BeWo human choriocarcinoma and two human embryonal carcinoma cell lines. The antibody did not react with 22 other cell lines or with hCG. The antibody was labeled with 131I and injected into nude mice bearing BeWo tumors and evaluated for tumor localization by performing whole body scans with a gamma camera 5 days later. Six mice injected with the antibody showed positive tumor localization without the need for background subtraction while six mice injected with MOPC-21, a murine myeloma immunoglobulin, demonstrated much less tumor localization. Tissue distribution studies performed after scanning showed specific tumor localization (8:1 tumor: muscle) for the monoclonal antibody and no specific localization for MOPC-21. This antibody thus has selective reactivity with the surface of tumor cells from embryonal carcinoma (testicle) and choriocarcinoma both in vitro and in vivo.  相似文献   
44.
The cigarette smoke-induced rat model of chronic bronchitis was used to study the time course of the return of cigarette smoke-induced secretory cell hyperplasia to the normal and the capacity of two non-steroidal anti-inflammatory drugs to speed this recovery. Cigarette smoke alone significantly increased (P less than 0.05) the number of secretory cells in all of the eight airway levels studied to between 52-225% above control values. After cessation of exposure, recovery was complete by 9 days in the trachea, between 10-21 days in 'proximal' intrapulmonary airways and 43-84 days in distal bronchioli. Indomethacin and flurbiprofen, given by intraperitoneal injection at 4 mg/kg body weight for 21 days of the recovery period, significantly reduced the time taken for recovery to between 4 and 9 days in intrapulmonary airways but had no effect in the trachea.  相似文献   
45.
Is EMDR an exposure therapy? A review of trauma protocols   总被引:1,自引:0,他引:1  
This article presents the well established theoretical base and clinical practice of exposure therapy for trauma. Necessary requirements for positive treatment results and contraindicated procedures are reviewed. EMDR is contrasted with these requirements and procedures. By the definitions and clinical practice of exposure therapy, the classification of EMDR poses some problems. As seen from the exposure therapy paradigm, its lack of physiological habituation and use of spontaneous association should result in negligible or negative effects rather than the well researched positive outcomes. Possible reasons for the effectiveness of EMDR are discussed, ranging from the fundamental nature of trauma reactions to the nonexposure mechanisms utilized in information processing models.  相似文献   
46.
Mixed organic brain syndrome as a manifestation of systemic mastocytosis   总被引:1,自引:0,他引:1  
Systemic mastocytosis is a disease characterized by an excessive accumulation of mast cells, and associated with skin lesions, flushing, diarrhea, tachycardia, and psychiatric manifestations. In order to define more clearly the psychiatric manifestations, ten patients with this disorder underwent unstructured psychiatric interviews and a battery of psychologic testing. Both revealed a pattern of cognitive and affective changes in the majority of these patients, best categorized as an atypical or mixed organic brain syndrome. The cognitive changes consisted of diminished attention and memory, and the affective changes of anger, irritability, and, to a lesser extent, depression. These manifestations fluctuated with the level of disease activity, and appeared in some cases to respond to histamine antagonists and disodium cromoglycate, medications used to control the excessive mast cell activity. It is important for psychiatrists to be aware that mental status changes can represent psychiatric manifestations of mastocytosis, a readily treatable medical disorder.  相似文献   
47.
Because chronic Mycoplasma pneumoniae respiratory infection is hypothesized to play a role in asthma, the potential of M. pneumoniae to establish chronic respiratory infection with associated pulmonary disease was investigated in a murine model. BALB/c mice were intranasally inoculated once with M. pneumoniae and examined at 109, 150, 245, 368, and 530 days postinoculation. M. pneumoniae was detected in bronchoalveolar lavage fluid by culture or PCR in 70 and 22% of mice at 109 and 530 days postinoculation, respectively. Lung histopathology was normal up to 368 days postinoculation. At 530 days, however, 78% of the mice inoculated with M. pneumoniae demonstrated abnormal histopathology characterized by peribronchial and perivascular mononuclear infiltrates. A mean histopathologic score (HPS) at 530 days of 5.1 was significantly greater (P < 0.01) than that for controls (HPS score of 0). Serum anti-M. pneumoniae immunoglobulin G was detectable in all of the mice inoculated with M. pneumoniae and was inversely correlated with HPS (r = -0.95, P = 0.01) at 530 days postinoculation. Unrestrained whole-body plethysmography measurement of enhanced pause revealed significantly elevated airway methacholine reactivity in M. pneumoniae-inoculated mice compared with that in controls at 245 days (P = 0.03) and increased airway obstruction at 530 days (P = 0.01). Murine M. pneumoniae respiratory infection can lead to chronic pulmonary disease characterized by airway hyperreactivity, airway obstruction, and histologic inflammation.  相似文献   
48.
Is the grading of breast carcinomas affected by a delay in fixation?   总被引:6,自引:0,他引:6  
Summary The effect of delay in fixation on the modified Bloom and Richardson grade of eight breast carcinomas was investigated. Topologically shuffled samples of each tumour were immersed in fixative at times of 0.5, 2, 4, 6, 18 and 24 h after surgical removal. The grade of each tumour was assessed at delays of 0.5 and 6 h. The tubule formation and nuclear pleomorphism components of the grade showed no change with a delay in fixation of 6 h. The number of mitotic figures declined by a mean of 53% over the same period and this resulted in a decrease in the histological grade of one of the tumours. The implications of these findings for the handling of breast specimens in a diagnostic histopathological laboratory are discussed.Some of these data were presented at the 162nd meeting of the Pathological Society of Great Britain and Ireland at Cambridge, 3 January 1991. Published as an abstract in J Pathol (1991) 163:154A  相似文献   
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