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91.
When splenic nonenhancement is seen at computed tomography, one should look for signs of vascular pedicle injury; if injury to the vascular pedicle is not present, nonenhancement of the spleen could be secondary to severe vasoconstriction and may be considered an additional sign of the hypoperfusion complex. The presence of splenic nonenhancement may also help differentiate the hypoperfusion complex from other types of bowel injury. 相似文献
92.
中药肉苁蓉及其同属生药对免疫功能及酯质过氧化的作用 总被引:2,自引:0,他引:2
肉苁蓉为我国著名补益中药。以不同种的肉苁蓉的乙酸乙酯提取物和水提取物进行免疫药理试验,以不同种的水提物进行对脂质过氧化影响的试验。结果表明不同种肉苁蓉的提取物有强度不同的增强免疫功能和抑制脂质过氧化作用。 相似文献
93.
Biochemical analysis of plasma-soluble invariant chains and their complex formation with soluble HLA-DR 总被引:1,自引:0,他引:1
The invariant chain (CD74) is preferentially localized in the cytoplasm and regulates the loading of exogenous derived peptides into HLA class II heterodimers. In addition, a small proportion of CD74:class II complexes is also expressed on the cell surface. We identified and quantified soluble CD74 (sCD74) molecules in the plasma and sCD74:sHLA-DR complexes by ELISA. EDTA plasma samples from 86 healthy probands were analyzed. sCD74 could be detected in all samples with a mean concentration of 1.14 relative units±1.04 SD (range 0.17-4.31). Approximately 10% of the samples had increased amounts of sCD74 (3.0 relative units). Complexes of sCD74 and sHLA-DR were detected in all samples and their quantities were positively correlated (r=0.83, p0.001) with the sCD74 concentrations. SDS-PAGE analysis of plasma samples with high sCD74 concentrations (3.0 relative units) revealed four isoforms of sCD74 with molecular weights of 45, 43, 35, 31 kDa corresponding to known sizes of intracellular CD74. However, only molecular weights of the 45 and 43 kDa isoforms of sCD74 are found complexed with sHLA-DR. Our data demonstrate, that CD74 molecules are present in their soluble form in the plasma of healthy probands and form complexes with soluble HLA-DR molecules. 相似文献
94.
卡氏肺孢子虫的超微结构观察 总被引:1,自引:0,他引:1
采用皮下注射醋酸可的松和低蛋白饲养方法诱发SD大鼠自然感染卡氏肺孢子虫后,取其肺组织,按常规方法进行透射电镜的系统观察。结果除为Yoshida提出的卡氏肺孢子虫生活史的有性增殖和无性增殖循环的最新设想提供了某些形态学依据外,还继Vossen等之后再次发现该病原在1型肺泡上皮细胞内寄生的情况。本文最后就卡氏肺孢子虫对宿主的致病机理进行了讨论。 相似文献
95.
口服耐受的机制及其在自身免疫病治疗中的应用 总被引:1,自引:0,他引:1
口服耐受是指口服蛋白引起的一种免疫低反应状态。自Wel1sl911年首先报道这种现象以来,口服耐受引起了广泛关注,大量研究者发现给动物饲服蛋白质或绵羊红细胞后,再次消化道外免疫时,动物对这些抗原不再具有良好的反应性,而对其它抗原的反应正常[1]。免疫... 相似文献
96.
Cross-linking induced interactions between the membrane form of immunoglobulin (mIg) and the cytoskeletal matrix have been described by several groups. To date, the function of mIgM association with the cytoskeleton is not yet understood. Delineation of the molecular basis of these interactions will be instrumental in elucidating their function. We have previously shown that the Igα/β heterodimer is not required for ligand-induced mIgM binding to the cytoskeleton. In this study, we have investigated the role of other B cell-specific proteins in mediating these interactions. For this, we expressed mIgM in the non-hematopoietic human cervical carcinoma cell line HeLa S3 and verified the capacity of the surface-expressed IgM to interact with the cytoskeletal matrix upon cross-linking with anti-μ chain antibodies. We show here that only the mIgM molecule itself and no other B cell-specific protein(s) is required in mediating mIgM interactions with actin filaments. In an attempt to determine the cytoskeleton-binding site of mIgM we investigated the role of the cytoplasmic tail of mIgM (KVK) in binding the receptor to actin-based microfilaments. Using mutated forms of mIgM expressed in J558L cells, we show here that KVK plays a role in mediating these interactions. The absence of KVK did not, however, completely abrogate mIgM-cytoskeletal interactions, suggesting that there are additional molecular requirements for the ligand-induced mIgM binding to the cytoskeletal matrix. 相似文献
97.
Eduardo M. B. Tinoco Ståle P. Lyngstadaas Hans R. Preus Per Gjermo 《Journal of clinical periodontology》1997,24(12):937-944
Abstract Immunological data have been suggested to be a potential tool in the diagnosis, classification and monitoring of periodontal diseases. However, the role of circulating antibodies in periodontal patients is poorly understood. Patients suffering from localized juvenile periodontitis (LJP) are often reported to show high titers of serum IgG antibodies against Aetinobaeillus actinomycetemcomitans (A. actinomycetemcotnitans), but several affected patients do not. Most studies use well-known reference strains of the bacterium for testing against the patients' sera. The aim of the present investigation was to study the relationship between serum IgG antibody levels to autologous A. actinomycetemcomitans strains and clinical attachment loss (CAL). In addition, we wanted to assess the patients’serum titers against 4 well-known reference strains of the bacterium as well as their general potential immunoglobulin response. Intravenous blood samples were taken from 23 LJP patients and 10 healthy individuals, and autologous A. actinomycetemcomitans strains were cultured from 18 of the L.JP patients. CAL was measured at 4 different sites around ail present teeth and assessed as a % of teeth with at least 1 site moderately ≥2<5 mm) or severely (≥5 mm) involved. An enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the serum titers of IgG antibodies to A. actinomycetemcomitans antigens. No significant correlation was found between serum IgG antibody titers to autologous strains and CAL. However, there was a trend that low responders had more moderately affected teeth than had high responders and patients with undetectable A. actinomycetemcomitans levels, which is in agreement with a hypothetically protective role of the antibodies. The total counts of immunoglobulin assessed in all participants showed that the predominant class was IgG and the reference group displayed significantly less (p<0.05) IgG and IgG1 counts than the LJP patients. Both the reaction pattern against reference and autologous strains varied widely. We conclude that the specific antibody response against A. actinomycetemcomitans shows a weak correlation to clinical attachment levels in LJP patients. 相似文献
98.
Melinda Braskett MD Robert L. Roberts MD PhD 《Clinical Pediatric Emergency Medicine》2007,8(2):96-103
The potential for morbidity and mortality in patients who have PID with febrile and nonfebrile illness is extremely high. Familiarity with the clinical manifestations of PID and collaboration with a pediatric immunologist are prerequisites for optimal short-term care of these complex patients. Conservative management with empiric broad-spectrum antimicrobials, early and aggressive surgical debridement of abscesses, and admission at a tertiary pediatric care center are often indicated. 相似文献
99.
Retrogradely transported fluorescent dyes (fast blue and diamidino-dihydrochloride yellow) were used to compare the distributions of trigeminofugal neurons that project to the superior colliculus and/or the thalamus in three rodent species. The objective was to determine what the projection and collateralization patterns of these trigeminofugal pathways are and whether they are similar among different species. In each anesthetized animal, one dye was injected into the superior colliculus and the other into the topographically congruent area of the thalamus. Counts of the numbers of yellow, blue, and double-labeled neurons were made throughout the trigeminal complex: principalis, pars oralis, pars interpolaris, and pars caudalis. Trigeminothalamic projections were similar in each of the rodent species studied. The densest concentration of retrogradely labeled neurons was in principalis, with substantially fewer neurons in pars interpolaris, and fewer still in pars oralis and pars caudalis. These neurons were generally small and tended to have round or fusiform somata. A common pattern was also noted among the three species for trigeminotectal neurons. Most trigeminotectal projections originated from neurons in pars interpolaris, somewhat fewer from pars oralis, and the fewest from principalis and pars caudalis. These neurons tended to be the largest in each subdivision and were often multipolar. Following paired injections of the tracers, double-labeled neurons were scattered throughout the sensory trigeminal complex and had morphologies characteristic of single-labeled trigeminotectal neurons. Although comparatively few double-labeled neurons were observed in any species, most of those seen were restricted to the ventrolateral portion of pars interpolaris, a position that corresponds to the representation of the vibrissae. These data indicate that, regardless of the rodent species, the vast majority of labeled trigeminal neurons project either to the superior colliculus or the thalamus, but not to both targets. This might be expected on the basis of the very different behavioral roles these structures play. On the other hand, a subpopulation of trigeminal neurons exists (mainly in pars interpolaris) that does project to both the superior colliculus and the thalamus, perhaps because both structures require some of the same somatosensory information to perform their behavioral functions. 相似文献
100.
Serum glomerular binding activity is highly correlated with renal disease in MRL/lpr mice. 总被引:3,自引:0,他引:3 下载免费PDF全文
The pathogenesis of lupus nephritis is felt to be mediated by anti-DNA antibodies. However, the anti-DNA response and renal disease do not entirely correspond. We recently developed a new assay which detects immune elements based on their ability to bind glomeruli as an alternative approach to understanding the pathogenesis of this disorder. The glomerular binding activity (GBA) defined by this assay consists of immune elements containing IgG which interact specifically with renal tissue, the binding of which is DNase-inhibitable, but which do not bind to DNA directly. In the current study we assessed the relationship between GBA and renal disease in MRL/lpr mice (both untreated and cyclophosphamide-treated) and compared it with the anti-DNA assay. Both assays were highly correlated with renal disease in untreated mice in terms of proteinuria. In cyclophosphamide-treated mice, however, only a weak correlation between the anti-DNA assay and proteinuria was apparent. GBA, in contrast, was more strongly correlated with proteinuria in treated mice. This correlation improved substantially when the DNase-sensitive component of the GBA was used. GBA appeared related to, but not covariant with, the anti-DNA response. These results demonstrate that GBA is a better correlate of murine lupus nephritis than the anti-DNA assay, and suggest that the immune elements detected by this assay, the DNase-sensitive component in particular, may be pathogenically important. 相似文献