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1.
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   
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Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.  相似文献   
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Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
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BACKGROUND: Percutaneous transluminal angioplasty (PTA) dilates constricted arteries at the circle of Willis to reverse cerebral ischemia caused by cerebral vasospasm. Although 90% of the patients show angiographic improvement after PTA, only 70% show clinical improvement. Why some patients do not improve after PTA is unknown. We report on a 48-year-old woman who failed to improve after PTA and died from aneurysm rerupture. Pathologic studies were performed to determine why PTA failed to reverse the symptoms of cerebral ischemia. METHODS: The arteries of the brain were studied by light microscopy using Gomori's trichrome stain. The arteries were also studied by scanning and transmission electron microscopy. RESULTS: The arteries that were dilated with PTA showed compression of the connective tissue, stretching of the internal elastic lamina, and a combination of compression and stretching of the smooth muscle. The small arteries and arterioles that had been treated with an infusion of intraarterial papaverine were constricted with a thickened intimal layer. CONCLUSION: The persistence of cerebral vasospasm in small and perforating arteries may contribute to the failure of cerebral ischemia to reverse after PTA.  相似文献   
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In 22 patients with purulent-septic complications the extracorporal attaching of the xenolien cryopreserved sections was applied together with conventional therapy. Distinct reduction of the endogenic intoxication severity an the immune state of patients normalization were noted.  相似文献   
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Palisaded neutrophilic and granulomatous dermatitis (PNGD) is commonly associated with underlying systemic inflammatory and neoplastic diseases, infections, and drug reactions. In vivo cutaneous antinuclear antibodies (ANA) have been described in skin biopsies from patients with known autoimmune disorders, but not previously reported in the setting of PNGD. We present two patients with systemic lupus erythematosus (SLE) and histopathologically confirmed PNGD. Direct immunofluorescence (DIF) studies revealed in vivo cutaneous ANA positivity in both patients. DIF findings in the skin mirrored serum autoantibody results. ANA positivity in skin specimens is reported as highly predictive of systemic connective tissue diseases (SCTD), although specific testing is not currently recommended as part of the laboratory work-up or diagnostic criteria for these disorders. In this case report, positive ANA results in skin biopsies of PNGD reflect the serological findings and clinical evidence of SLE in both patients. In vivo cutaneous ANA positivity is an interesting and supportive finding in PNGD in the setting of SCTD.  相似文献   
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Mixotrophic basis of Atlantic oligotrophic ecosystems   总被引:1,自引:0,他引:1  
Oligotrophic subtropical gyres are the largest oceanic ecosystems, covering >40% of the Earth's surface. Unicellular cyanobacteria and the smallest algae (plastidic protists) dominate CO(2) fixation in these ecosystems, competing for dissolved inorganic nutrients. Here we present direct evidence from the surface mixed layer of the subtropical gyres and adjacent equatorial and temperate regions of the Atlantic Ocean, collected on three Atlantic Meridional Transect cruises on consecutive years, that bacterioplankton are fed on by plastidic and aplastidic protists at comparable rates. Rates of bacterivory were similar in the light and dark. Furthermore, because of their higher abundance, it is the plastidic protists, rather than the aplastidic forms, that control bacterivory in these waters. These findings change our basic understanding of food web function in the open ocean, because plastidic protists should now be considered as the main bacterivores as well as the main CO(2) fixers in the oligotrophic gyres.  相似文献   
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