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101.
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata.  相似文献   
102.
Oophorectomized, estrogen-treated rats were susceptible to experimental vaginal infection by Candida albicans. After spontaneous clearing of the primary infection, the animals were highly resistant to a second vaginal challenge with the fungus. The vaginal fluid of Candida-resistant rats contained antibodies directed against mannan constituents and secretory aspartyl proteinase(s) of C. albicans and was capable of transferring a degree of anti-Candida protection to naive, nonimmunized rats. This passive protection was mediated by the immunoglobulin fraction of the vaginal fluid and was substantially abolished by preabsorption of the vaginal fluid with C. albicans, but not with Saccharomyces cerevisiae, cells. Vaginal anti-mannan antibodies were also produced by active immunization with heat-killed cells of C. albicans or with a mannan extract when administered via the vaginal route. The protection conferred was comparable to that resulting from clearing of the primary infection. In summary, the data suggest that acquired anticandidal protection in this vaginitis model is mediated at least in part by antibodies, among which those directed against the mannan antigen(s) might play a dominant role.  相似文献   
103.
Background: Bowel obstruction is a common and distressing outcomein patients with abdominal or pelvic cancer. Patients and methods: Patients may develop bowel obstructionat any time in their clinical history, with an incidence rangingfrom 5.5% to 42% in ovarian carcinoma and from 10% to 28.4%in colorectal cancer. The causes of the obstruction may be benignpostoperative adhesions, a focal malignant or benign deposit,relapse or diffuse carcinomatosis. The symptoms which are almostalways present are intestinal colic (reported in 72%–76%of patients), abdominal pain due to distension, hepatomegalyor tumor masses (in 92% of patients) and vomiting (68%–100%)of cases. Conclusion: While surgery must remain the primary treatmentfor malignant obstruction, it is now recognised that there isa group of patients with advanced disease or poor general conditionwho are unfit for surgery and require alternative managementto relieve distressing symptoms. A number of treatment optionsare now available for the patient with advanced cancer who developsintestinal obstruction. In this review of the literature, theindications for surgery will be examined, the use of nasogastrictube and percutaneous gastrostomy evaluated and the place ofdrugs for symptom control described. bowel obstruction, advanced and terminal cancer patients  相似文献   
104.
A vaccination trial, performed on 86 3-month-old infants, has shown that the ability of the RIT 4237 live attenuated rotavirus strain to induce seroconversion is dramatically reduced when administered with live poliovirus vaccine. In a subsequent trial performed on 93 infants the attempt to overcome the poliovirus interference by administering two doses of associated vaccines was unsuccessful. No interference by the RIT 4237 strain on live attenuated polioviruses was observed.  相似文献   
105.
The EUROCAT programme is a concerted action of the European Economic Community for the epidemiologic surveillance of congenital anomalies. Surveillance is based on a network of regional registries coordinated by a central registry. The programme started in 1979 and by 1987, 23 centres were participating, covering together more than 300,000 births per year. The surveillance process implies the selection of the anomalies possibly associated with environmental teratogens or mutagens, the definition of abnormal variations in the rate of these anomalies (the alarms), the establishment of base-line rate and the continuous monitoring of rate. The programme is evaluated by reference to four criteria: the sensitivity of the system in detecting teratogens or mutagens, the specificity of alarms, the rapidity in warning of alarm and in investigating their causes, and the programme efficiency expressed as its cost-utility ratio.  相似文献   
106.
The paper demonstrate the surgical approach used by the authors to implant the AMS 700CX penile prosthesis. Pre- and postoperative management are also discussed.  相似文献   
107.
The neutrophil (PMN) receptor for formylated peptides such as N-formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP) is involved in binding and subsequent response to certain chemotactic stimuli. The receptor on human PMN has been reported to consist of several glycoprotein components, ranging in size from 43-94 kDa. Furthermore, FMLP receptors on human PMN have been shown to contain both high and low affinity states. In this study, the receptor was purified by subjecting solubilized PMN plasma membrane components to FMLP-affinity chromatography, and was found to be comprised of four components, one of 68 kDa, and the others of 94, 48, and approximately 40 kDa. Only the 68, the 94, and the approximately 40 kDa components specifically bound a radioiodinated FMLP analogue. To further characterize these components, a battery of monoclonal antibodies reactive against the FMLP receptor was prepared. Seven monoclonal antibodies were selected on the basis of their reactivity with the 68 kDa receptor component. Some of these antibodies also cross-react with the 48 kDa component, suggesting that the 68 and the 48 kDa receptor moieties are immunologically related. These antibodies reacted with normal human neutrophils, but not with lymphocytes, or unstimulated HL-60 cells. Furthermore, the presence of 20 nmol of FMLP inhibited the binding of five of the anti-receptor antibodies to whole PMN. These results suggest that the epitopes recognized by these five antibodies may possibly be involved in FMLP binding.  相似文献   
108.
The time-dependent release by human alpha-thrombin of the physiological variants of fibrinopeptide A, i.e. fibrinopeptide A-3-phosphate (FPAP) and des-Ala-fibrinopeptide A (FPAY), has been measured in order to study the kinetic pathway for their hydrolysis. The best-fit kinetic model for the release of FPAP and FPAY is consistent with a simple pseudo first-order reaction, as observed with FPA. These findings indicate that FPAP and FPAY are also released from intact fibrinogen before release of FPB. The values of the specificity constants, i.e. k(at)/Km, for the enzymatic reaction between thrombin and the various alpha-chains showed that AP alpha- and AY alpha-chain are hydrolyzed with a 0.2-and 0.4-fold higher specificity constant respectively than that of A alpha-chain. Such minor differences observed with the various chains suggest that the 1-3 NH2-terminal residues of the chain do not significantly contribute to the catalytic efficiency of thrombin toward the alpha-chains of fibrinogen.  相似文献   
109.
110.
We studied the effect of mast cell chymase on the thyroid cells in culture. Rat serosal mast cells, similar functionally to connective tissue mast cells, were obtained after lavage of the peritoneal cavity and lyzed by freezing. The resulting lysate was used as crude enzyme preparation. Mast cell chymase was purified from the crude preparation by anion exchange chromatography. Crude and purified chymase incubated with thyroid cells induced cellular retraction, the appearance of long processes and gradual cell detachment from the substratum. The effect of the enzyme was not cytotoxic. The immunofluorescence studies of thyroid cells showed a decreased amount of polymerized actin and tubulin after incubation with chymase. Neutral protease inhibitor abolished the effect of crude and purified chymase on thyroid cell morphology. The above findings suggest that mast cell chymase may have a function in the control of cell morphology and cell-matrix interaction.  相似文献   
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