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991.
Oral allergy syndrome induced by spinach   总被引:1,自引:1,他引:0  
  相似文献   
992.
AIMS: Immunohistological and molecular characterisation of a case of peripheral T-cell lymphoma (PTCL) of angioimmunoblastic T-cell lymphoma (AILD) type. METHODS: Frozen and paraffin wax sections of the diagnostic lymph node were stained with a panel of T- and B-cell lineage monoclonal antibodies. DNA was isolated from the paraffin wax embedded biopsy material for T-cell receptor (TCR) and immunoglobulin (Ig) PCR amplification, and resultant PCR products were cloned and sequenced. RESULTS: Immunohistological analysis of the presenting lymph node was consistent with an extensive infiltrate of pleomorphic CD3+CD8+ lymphocytes. Most (>80%) of these infiltrating CD3+ cells were also positive for the TCR VB5.1 gene family product, and were shown to be oligoclonal by TCRB PCR amplification and sequencing. Three oligoclones of B cells were also demonstrable by PCR amplification with Ig heavy chain primers and sequencing, a finding at variance with the diagnosis of AILD. CONCLUSIONS: These data demonstrate the complexity and heterogeneity of PTCL which require extensive histological examination and molecular characterisation.  相似文献   
993.
Reactive oxygen species and human spermatozoa: physiology and pathology   总被引:20,自引:1,他引:19  
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial.  相似文献   
994.
Recurrent dislocation of the patella and the Goldthwait operation   总被引:1,自引:0,他引:1  
In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after their Goldthwait operation. The subjective and clinical findings were excellent or good in 70%. X-radiographs indicated osteoarthritis of the femoropatellar joint in 60%. Concerning the aetiopathological factors, we found an increased external torsion of the afflicted extremity (measured by computed tomography).  相似文献   
995.
996.
997.
The pulsed tunable dye laser (PTDL) is generally considered to have a very low incidence of adverse effects, allowing it to become the treatment of choice for the majority of port wine stains (PWS). The low incidence of adverse effects has led to difficulties in determining the true incidence and type of adverse effect seen with this laser. We therefore undertook a retrospective study of 701 patients with PWS, who received 3877 full treatments to determine the incidence and type of adverse effects seen following treatment with the PTDL. Blistering and crusting were seen in 5·9% and 0·7% of patients, respectively, but were transient events which usually healed without permanent sequelae. Hyperpigmentation was the most frequently observed adverse effect seen in 9·1% of patients but generally showed gradual resolution over 6–12 months. Hypopigmentation was infrequent, seen in 1.4% of patients. The most significant adverse effects were atrophic and hypertrophic scarring seen in 4·3% and 0·7% of patients, respectively. Our observations show that there is a small but definite risk of atrophic scarring with a predisposition for younger patients. Hypertrophic scarring can occur albeit rarely and there may be a predisposition towards the neck. In most cases test areas were not predictive of scarring. This underlines the need for a full discussion of scarring risk in patients with PWS undergoing treatment with the PTDL.  相似文献   
998.
Specific cutaneous lesions are a rare occurrence in myelodysplastic syndromes (MDS). The concurrent association of blistering skin lesions similar to those in bullous pemphigoid (BP), even though a rare event, suggests that BP may be a paraneoplastic syndrome. We report an 86-year-old man who had a refractory anaemia with excess bone marrow blasts in transformation, who developed a generalized pruritic blistering eruption. Immunohistopathological tests showed subepidermal blisters with linear deposits of IgG and C3 along the basement membrane zone of the epidermis surrounding a tumoral dermal infiltrate of CD13+ and CD15+ cells. Immunoblotting studies using epidermal extracts revealed circulating IgG antibodies against three protein bands: a 210–215 kDa band. a 180kDa band which co-migrated with the BP 180 antigen, and a 190kDa band. The tumour infiltrate may have revealed antigenic determinants which led to the onset of BP. The concept of paraneoplastic pemphigoid remains to be either confirmed or invalidated by further epidemiological studies.  相似文献   
999.
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.  相似文献   
1000.
Effects of capsaicin in temporomandibular joint arthritis in rats   总被引:8,自引:0,他引:8  
Temporomandibular joint (TMJ) arthritis was induced in female Lewis rats by unilateral injection of a suspension of heat-killed Mycobacterium butyricum in paraffin oil into the TMJ. Control rats received paraffin oil by the same route. Arthritic and control rats were pretreated either with capsaicin or denervation of the mandibular branch of the trigeminal nerve. Tissues were collected for neuropeptide extraction and analysed by radioimmunoassay and reverse-phase high-performance liquid chromatography. In all groups, the levels of substance P- (SP), calcitonin gene-related peptide- (CGRP) and neuropeptide Y- (NPY) like immunoreactivity (LI) were higher in the trigeminal ganglia than in the TMJs. In control rats, capsaicin significantly lowered the levels of SP-LI in the trigeminal ganglia and TMJ, but not CGRP-LI and NPY-LI. In the arthritic rats, capsaicin pretreatment significantly lowered the SP-LI and CGRP-LI in the trigeminal ganglia and TMJ, but not the NPY-LI. In the trigeminal ganglia the unilateral denervation significantly lowered SP-LI in control rats, and in arthritic rats SP-LI and CGRP-LI. On the denervated side of the arthritic TMJ, NPY-LI, SP-LI and CGRP- LI were significantly lowered as compared to the arthritic control rats and to the contralateral side. In this rat model, pretreatment with capsaicin and surgical denervation decreased the neuropeptide content in the trigeminal ganglia and the TMJ. The results clearly demonstrate a close interaction between increased neuropeptide release from sensory and sympathetic neurones after induction of arthritis in the rat.  相似文献   
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