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31.
Immunologic studies were performed on 5 patients with pigeon breeders' disease. Intradermal injection of pigeon serum produced an immediate wheal-and-flare reaction within 15 minutes and a secondary Arthus-type reaction within 4 to 8 hours. Immunofluorescent studies of the secondary reaction site showed IgG, C3, and C4 in 2 patients. Patients' sera produced multiple precipitin bands with pigeon serum when reacted by double diffusion in gel. IgG antibody isolated from each of the patients' serum formed precipitating immune complexes that fixed large amounts of complement (C4) when added to fresh human serum. Peripheral blood lymphocytes from 4 of the 5 patients produced macrophage migration inhibitory factor (MIF) when challenged with dilute pigeon serum. These studies are the first to show complement fixing antibodies and macrophage MIF production by lymphocytes from patients with hypersensitivity lung disease and suggest that both humoral and cellular immunity may be important in the pathogenesis of these disorders.  相似文献   
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Primary and revision total knee arthroplasty have become common orthopaedic procedures. The operating surgeon, at times, may be faced with a difficult surgical case due to soft tissue contractures or bone deformities. A review of multiple surgical techniques using soft tissue releases and osteotomies are presented including their potential complications. Although these techniques are aimed at the atypical operative case, the operating surgeon may utilize them for ‘routine’ exposures as well. Importance is focused on the functional integrity of the knee extensor mechanism.  相似文献   
35.
The CD45 antigen family consists of multiple molecular isoforms ranging from 180 to 220 kDa. The highest Mr isoforms are recognized by monoclonal antibodies (MoAbs) designated CD45RA, while those recognizing the low Mr isoforms are designated CD45RO. T cells expressing CD45RA are "naive" or unprimed, while those expressing CD45RO have "memory." Further, stimulation of CD45RA+ T cells induces an isoform switch to the CD45RA-/CD45RO+ phenotype. The present study examined this in vitro process by determining the in vivo CD45 isoform expression of T cells from human hyperplastic lymph nodes. Hyperplastic, as opposed to nonhyperplastic, lymph nodes exhibited the expected CD45 isoform switch from CD45RA+ to CD45RO+ T cells that has been described in vitro. The percentage of CD45RO+ T cells did not correlate with other parameters of lymphoid activation. Thus, CD45RO expression probably represents a marker of differentiation and acquisition of "memory" or late cellular activation.  相似文献   
36.
We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation.  相似文献   
37.
Chlamydia trachomatis is a strict human pathogen producing infections that cause medically important chronic inflammatory diseases, such as blinding trachoma and tubal factor infertility. Isolates exist as serotypes that fall into distinct biologic and pathological groups corresponding to differences in infection tissue tropism and invasion properties. Paradoxically, genome sequencing of several diverse strains has revealed a remarkable level of genomic synteny, suggesting that minor genetic differences determine the pathogen host- and tissue-specific infection characteristics. To better understand the genetic basis of chlamydial pathobiologic diversity, we performed comparative DNA-DNA microarray genomic hybridizations with all 15 C. trachomatis serovariants. We found there are few major genetic differences among the 15 serovars. An exception was the cytotoxin locus located in the plasticity zone, a region that exhibited significant polymorphisms among serovars. We therefore sequenced this region from all 15 serovars. The cytotoxin gene was interrupted by extensive mutations and deletions among the different serovars; however, three basic open reading frame motifs were discovered that correlated with noninvasive oculotropic, urogenitotropic, and invasive serovars. Of interest, only noninvasive genitotropic serovars possessed an intact N-terminal portion of the putative toxin gene. This region contains the UDP-glucose binding domain and the glycosyltransferase domain required for enzymatic activity of the clostridial toxin homologs, suggesting a role in urogenital infection or pathogenesis.  相似文献   
38.
A virus (PBCV) from the symbiotic Chlorella-like algae of Paramecium bursaria has been characterized by sedimentation field flow fractionation (SdFFF). The method yields effective molecular weight M' (molecular weight X buoyancy factor) with a precision of better than 5% under a variety of experimental conditions. The value for M' is used to calculate true molecular weight values through combination with density values; densities were obtained from outside sources, from ultrasonic densitometry, and from sedimentation coefficients determined independently. The actual molecular weight is also determined through SdFFF analysis of the virus in carriers of different densities. Values for the particle diameter are obtained from SdFFF zone broadening studies. The various SdFFF characterization results are compared with molecular weight, particle size, and density values determined by conventional methods.  相似文献   
39.
Polystyrene (PS) latex particles of different sizes were adsorption coated with the polymeric surfactant Pluronic F108 (PEO129-PPO56-PEO129). The commercial surfactant was found to have a bimodal molecular weight distribution. However, the maximum surface concentrations resulting from adsorption of either the purified high molecular weight component or the composite were identical. An increase in the copolymer surface concentration on 252-nm particles was found to decrease their fibrinogen uptake exponentially. At maximum copolymer surface concentration, the fibrinogen uptake was two orders of magnitude lower than that of bare particles (down from 3.3 mg/m2 to 0.03 mg/m2). This surface protection was equally effective whether the adsorption involved the bimodal polymer surfactant or the purified high molecular weight fraction. The PEO tail mobility was investigated with electron paramagnetic resonance (EPR), and found to increase with an increase in polymer surface concentration. The comparatively slow motion of the PEO chains at low surface concentration indicated that not only the PPO block, but also the PEO blocks interacted hydrophobically with the PS surface. When the copolymer surface concentration was increased, the PEO tails were gradually being released, acquiring higher mobility as the surface became covered by the more strongly binding PPO blocks. Results obtained with F108 coated particles of different sizes showed that particle size had a significant effect on the fibrinogen uptake, with larger particles showing larger fibrinogen uptakes.  相似文献   
40.
T Lehner  S J Challacombe    J Caldwell 《Immunology》1980,41(4):857-864
The oral route of immunization with Streptococcus mutants was compared with the subcutaneous route in rhesus monkeys. Significant levels of serum IgG, IgM and IgA antibodies in Strep. mutans were elicited only in monkeys immunized subcutaneously. Similarly, the skin delayed hypersensitivity reaction to Strep. mutans was elicited only in the subcutaneously immunized monkeys. Oral immunization induced a modest increase in salivary IgA antibodies to Strep. mutans, though a slight increase in IgA antibodies was also found in the saliva of all other groups of immunized and control monkeys. A small though not significant reduction in dental caries was found in the monkeys immunized orally, whereas subcutaneous immunization with Strep. mutans consistently elicited a significant reduction in caries. Oral feeding of Strep. mutans failed to induce tolerance to a subsequent subcutaneous challenge by the same organism. Furthermore, sequential subcutaneous followed by oral immunization had little effect on the titre of salivary or serum antibodies.  相似文献   
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