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991.
Primary malignant melanoma of the esophagus is a very rare and deadly disease, with a survival of 2.2% at 5 years and a median survival of about 10 months. The aggressive biological behavior of this disease and advanced stage at the time of diagnosis together with the lack of effective treatment have contributed to its poor prognosis. We present the case of a 45-year-old Japanese man diagnosed as having a primary melanoma of the esophagus by clinical evaluation and a histological examination of endoscopic biopsy specimens. A novel approach consisting of pre- and post-operative chemo-hormone therapy with dacarbazine, nimustine, cisplatin and tamoxifen in conjunction with radical esophagectomy accompanied by lymph node dissection was carried out. The tumor size was decreased to 70% by the pre-operative chemo-hormone therapy. During the post-operative 32 months of follow-up, no evidence of recurrence or metastatic disease has been found. Although this is only one case, the outcome observed suggests that the combination of pre- and post-operative chemo-hormone therapy and radical esophagectomy with lymph node dissection is a modality that can increase the possibility of curability or at least improve the survival of patients with primary melanoma of the esophagus.   相似文献   
992.
Three hundred and eighty-two patients with known inflammatory bowel disease (IBD) (190 European and 192 Asian) and 190 with coeliac disease were sent a previously validated questionnaire to investigate patients' use of alternative medicine and their views on its effectiveness. Details sought included whether they had ever consulted an alternative practitioner, whether they had followed a course of treatment and its clinical effects. Information about where patients had heard about such alternative practitioners and whether they were told to discontinue their current allopathic medication was also sought. Results were analysed after three consecutive mailings, including one in Gujurati to Asian patients. A randomly selected group was re-interviewed four months later. To validate the study alternative medicine practitioners were also interviewed to investigate what percentage of their attendees have IBD and how many of those clients were Asians.One hundred and fifty-eight questionnaires were returned from European patients with IBD (response rate = 83%), 145 from patients with coeliac disease (response rate = 76%) but only 81 Asian patients with IBD (response rate = 42%). Forty-seven European and Asian patients with inflammatory bowel disease sought advice or treatment from an alternative practitioner, compared with only 11 with coeliac disease (X2 = 11.64, df = 12, P < 0.003). There was no significant difference in consultation rates between Asian and European patients with IBD (Yates corrected X2 = 0.78, ns). The most common practitioners consulted by all groups were homeopaths (n = 23) and herbalists (n = 27) but 20 patients consulted more than one practitioner at a time. Patients with coeliac disease and European patients with IBD had consulted osteopaths (n = 6) and reflexologists (n = 7). Ten patients with IBD had also attended a spiritualist and five Asian patients a hakim. Common sources of information about alternative remedies included friends and relatives (n = 13), the media (n = 11), word of mouth (n = 11) and family practitioners (n = 6). Most patients were advised to continue their current medications, although two had been told to stop and 10 advised to reduce the dose of their allopathic medications. Twenty alternative medicine practitioners stated that overall between 2–5% of their attendees have IBD with 10% of those clients being Asian. Asians preferred to consult Asian practitioners rather than European practitioners. There was no clear consensus as to whether complementary therapies were felt beneficial, although many patients with IBD believed them to be helpful.  相似文献   
993.
From January 1963 until January 1974, 45 patients had prosthetic valve endocarditis. Symptoms of prosthetic valve endocarditis developed within 2 months after operation (early onset) in 16 patients (36%) and more than 2 months after operation (late onset) in 29 patients (64%). Overall mortality among the 45 patients was 56% (88% among those with early onset and 40% among those with late onset). Medical therapy alone was curative in 60% of the surviving patients. Combined medical and surgical therapy was curative in 40% of the survivors. The most frequent isolates in the early-onset group were Staphylococcus aureus (44%) and Gram-negative bacilli (38%); associated mortality was 86% and 83%, respectively. The most frequent isolates in the late-onset group were viridans streptococci (41%) and Gram-negative bacilli (31%); the mortality was 25% and 22% respectively. Suggestions are offered for operative antimicrobial prophylaxis and for medical and surgical treatment of prosthetic valve endocarditis. Prompt surgical replacement of an infected prosthesis is necessary when medical therapy fails.  相似文献   
994.
Cytogenetic studies were performed on direct and 24-hour culture preparations of eight lymph node biopsies from seven patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC)- associated lymphadenopathy in whom histological evidence of lymphoma was not detected. Three of these seven had chromosomal abnormalities, including chromosome instability in one and clonal chromosomal abnormalities in two; one of the latter was a t(8;14)(q24;q32). The remaining five showed normal karyotypes. Epstein-Barr virus (EBV) titers were elevated in all three patients that exhibited chromosome abnormalities, two of whom later developed malignant lymphoma. A control group of five patients with reactive lymphadenopathy not associated with AIDS failed to reveal chromosomal aberrations, but elevated EBV titers were present in two. These data are consistent with current views on the role of EBV and chromosome change in the development of lymphoma in immunodeficient states and suggest that karyotypically abnormal AIDS-related lymphadenopathy represents a prelymphomatous proliferation.  相似文献   
995.
996.
997.
CD34 is expressed on the surface of hematopoietic stem/progenitor cells, stromal cells, and on the surface of high-endothelial venules (HEV). CD34 binds L-selectin, an adhesion molecule important for leukocyte rolling on venules and lymphocyte homing to peripheral lymph nodes (PLN). We generated CD34-deficient mutant animals through the use of homologous recombination. Wild-type and mutant animals showed no differences in lymphocyte binding to PLN HEV, in leukocyte rolling on venules or homing to PLN, in neutrophil extravasation into peritoneum in response to inflammatory stimulus, nor in delayed type hypersensitivity. Anti-L-selectin monoclonal antibody (MEL-14) also inhibited these immune responses similarly in both CD34-deficient and wild-type mice. However, eosinophil accumulation in the lung after inhalation of a model allergen, ovalbumin, is several-fold lower in mutant mice. We found no abnormalities in hematopoiesis in adult mice and interactions between mutant progenitor cells and a stromal cell line in vitro were normal. No differences existed in the recovery of progenitor cells after 5-fluorouracil treatment, nor in the mobilization of progenitor cells after granulocyte colony-stimulating factor treatment compared with wild-type animals. Surprisingly, although CD34 was not expressed in these mice, a portion of its 90-kD band crossreactive with MECA79 remained after Western blot. Thus, we have identified an additional molecule(s) that might be involved in leukocyte trafficking. These results indicate that CD34 plays an important role in eosinophil trafficking into the lung.  相似文献   
998.
The pathophysiology and clinical relevance of platelet heterogeneity   总被引:5,自引:0,他引:5  
Thompson  CB; Jakubowski  JA 《Blood》1988,72(1):1-8
Recent studies on platelet heterogeneity support the hypothesis that platelet production is regulated to maintain a constant functional platelet mass. In concept this form of regulation is analogous to the manner by which RBC production is controlled to maintain the oxygen- carrying capacity of blood. The platelet mass appears to correlate more closely with platelet function than the platelet count alone, since several factors in addition to the platelet count have been shown to influence the platelets' hemostatic function. These factors include platelet size, density, age, and previous hemostatic interactions. Application of these concepts to clinical problems has provided important insights into platelet physiology and reactivity. Failure to account for differences in platelet heterogeneity among individuals may introduce significant errors in the interpretation of data from laboratory and clinical investigations. However, despite advances, a number of practical issues remain to be resolved before measurements of platelet heterogeneity become accepted as routine clinical tests and are used in the diagnosis of pathologic states.  相似文献   
999.
Function-related antigens on the neutrophil (PMN) surface were identified using two newly developed PMN-specific mouse monoclonal antibodies. These IgG antibodies, designated Ab 1-14 and Ab 1-15, were selected for detailed study after initial testing revealed their significant inhibition of PMN superoxide generation in response to N- formyl-Met-Leu-Phe (FMLP) (64% for 1-14 and 64% for 1-15; P less than .05). In further experiments, Ab 1-14 augmented PMN adhesion (by 111%; P less than .01) and degranulation (by 52%; P less than .05) in response to FMLP, while Ab 1-15 inhibited these responses by 42% and 29%, respectively (P less than .05). Ab 1-14 reduced PMN chemotaxis in response to FMLP by 37% (P less than .02), and unlike Ab 1-15, Ab 1-14 significantly reduced unstimulated PMN binding of complement-coated sheep red blood cells. Ab 1-14 and Ab 1-15 significantly reduced PMN superoxide production in response to phorbol myristate acetate (PMA) (14% and 23%, respectively; P less than .05). Whereas 1-14 was found to increase PMA-induced cell degranulation significantly (175%), Ab 1-15 did not alter degranulation response to PMA. Immunoprecipitation showed that Ab 1-14 and Ab 1-15 recognized respective surface antigens of 94,000 mol wt and 130,000 to 180,000 mol wt. Our findings suggest that the surface molecules identified by these two monoclonal antibodies play a significant role in neutrophil activation by both FMLP and PMA.  相似文献   
1000.
Expression of terminal transferase (TdT) is believed to be restricted to primitive lymphoid cells; recently, however, indirect immunofluorescent (IF) assays have been used to demonstrate the apparent presence of TdT in phytohemagglutinin (PHA)-stimulated peripheral blood lymphocytes and in various nonlymphoid malignancies. Using an IF assay, we found that a heteroantiserum to TdT reacted with cultured and PHA-stimulated human peripheral blood mononuclear cells, but we were unable to confirm the presence of TdT in these cells using immunoblotting and biochemical assays. We conclude that the IF results are spurious and most likely represent recognition by the heteroantiserum of inducible protein(s) other than TdT.  相似文献   
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