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1.
To verify whether anti-Trypanosoma-cruzi-proteinase antibodies are able to play a role in the development of Chagas' disease, CBA/J and C57BL/6 mice were immunized with purified proteinase fractions: antibody production was studied and passive immunization experiments were carried out. No significant differences were observed in the titre, isotype composition and specificity of the antibodies produced by the mouse strains. Immune sera produced in one strain was able to protect mice of both strains, provided that the challenge did not exceed the number of parasites corresponding to 30-fold the LD50. The data presented suggest that anti-proteinase antibodies may play a role in immunoprotection.  相似文献   
2.
We measured platelet-rich plasma (PRP) serotonin in patients suffering from tension-type headache, before and after treatment with amitriptyline, comparing them with a healthy control group and patients with untreated depression. We evaluated the severity of headache and depression in each group. PRP serotonin levels were higher in patients with headache than in controls and depressed patients. We observed a fall of PRP serotonin in patients with tension-type headache to similar levels after treatment as the depressed group. This fall was correlated with the improvement of headache but not with depression scales. Our data suggest that the rise of platelet serotonin levels in tension-type headache is related to pain and not depression.  相似文献   
3.
To determine the utility of tissue section immunochemistry in the evaluation of bone marrow involved by lymphoid and plasma cell malignancies, snap-frozen, undecalcified bone marrow core and aspirate samples from 23 patients with these disorders were studied with a battery of monoclonal antibodies. With techniques that preserve architecture, difficult diagnostic cases characterized by core but not aspirate involvement, or the reverse, were resolved. By means of an extensive battery of monoclonal antibodies applied to serial sections, complex tumor cell phenotypes were established in all 23 cases. In addition to the identification of straightforward monoclonal surface immunoglobulin expression in small cleaved cell lymphomas (four cases), the battery approach added immunologic certainty in malignancies with unusual or difficult phenotypes: peripheral T-cell lymphomas with idiosyncratic antigen expression, and chronic lymphocytic leukemias and small cell lymphomas with faint surface immunoglobulin expression (four cases). For the chronic lymphocytic leukemias and the small cell lymphomas, the combined IgD+, B2+, B1+, Ia+, Leu-1+ phenotype taken as a whole had greater utility than any isolated marker. The acute lymphocytic leukemias and the myelomas studied demonstrate the wide range of B-cell antigens that must be detected to account for the variety of B-cell neoplasms encountered. Additionally, the previously undescribed phenotypic subset of CALLA+ myelomas, which is of prognostic relevance, was identified. Marrow frozen section immunotyping is a major asset in the evaluation of patients with lymphoma, leukemia, and myeloma when special care is accorded to tissue handling and to treatment of endogenous peroxidase/pseudoperoxidase and interstitial immunoglobulin.  相似文献   
4.
Arginase activity was measured in serum and biopsy from healthy individuals and colorectal cancer patients. Arginase activity in tumor samples (87±7.7 U/g tissue) was significantly higher than in controls (40.7±3.3 U/g tissue). However, serum arginase activity did not show any significant change in both groups. Finally, the micromethod used to quantify arginase activity in this study is superior to other methods because it has increased sensitivity, requires less sample, and is less time-consuming. Arginase differences are significant, according to the t-test (P<0.05). Received: 14 September 2001 / Accepted: 6 February 2002  相似文献   
5.
Identification of two major B cell forms of nodular mixed lymphoma   总被引:2,自引:0,他引:2  
To resolve the controversy over the immunologic nature of nodular mixed lymphoma (NM), we examined nine cases of NM for surface antigens using both tissue section and cell suspension methods. These were contrasted with 12 cases of nodular poorly differentiated lymphocytic lymphoma. We found two major B cell types of NM, those with monoclonal immunoglobulin (SIg+)-positive nodules with an SIg+B1+B2+Ia+T- phenotype (four cases) and those with nodules devoid of immunoglobulin with an SIg-B1+B2-Ia+T- phenotype (five cases). Our SIg+ NM cases appear similar to nodular poorly differentiated lymphocytic lymphoma (SIg+B1+B2+Ia+T-), except suspension assay indicates fewer SIg+ cells in NM. In our SIg- NM cases, the neoplastic nodules consistently expressed B1 and Ia-like antigens and lacked T cells, indicating a B cell neoplasm similar to many large cell lymphomas. By demonstrating a B cell antigen in SIg- nodules, we substantially resolve the controversial NM cases previously called "null" or T cell. The two distinct immunotypes indicate the complexity of B cell antigenic expression in NM and might also explain the variable response to therapy in NM described in previous studies. Finally, we describe NM cases with the simultaneous occurrence of several stages of B cell differentiation. This suggests that some NM cases are not frozen in a single stage of B cell development but may express a range of B cell antigens. NM, then, may be a paradigm of variable, simultaneous B cell maturation.  相似文献   
6.
Neurosurgical Review - The current literature regarding surgical treatment for tumors in the sphenopetroclival (SPC) region is merely scarce. Through a comprehensive literature review, we...  相似文献   
7.
8.
Several studies have suggested that human semen quality has declined over the past decades and some of them have associated it with occupational exposure to pesticides. However, most of these studies have not been associated with a reliable exposure level and have been designed mostly as cross-sectional studies. The present work evaluates, in a longitudinal follow-up study, the effect of organophosphate pesticides (OP) at three occupational exposure levels on semen quality. In addition, the study examined the association between OP urinary levels and sperm parameters in exposed and unexposed workers. A total of 139 semen samples from 52 volunteers were assessed. Urinary OP levels were measured by gas-liquid chromatography.The results revealed that the poorest semen quality was found among the subjects with the highest OP exposure and the highest urinary OP levels. Seasonal variations in sperm concentration and sperm count were registered.The results showed a significant decrease in total sperm count among subjects with the highest exposure to OP. Further studies assessing the effects of OP on male reproductive health should be controlled by the variability in human sperm parameters, sperm seasonality, spermatogenesis time and the changing OP exposure level in men highly exposed to OP.  相似文献   
9.
Orthotopic liver transplantation (OLT) is the treatment of choice for patients with acute or chronic end-stage liver disease, irresectable primary liver tumor, and metabolic disorders. Historically, OLT has been associated with considerable blood loss and the need for transfusions. However, over the years there has been reduction is need for blood products. The aim of this article was to compare two distinct eras for perioperative blood transfusion rate among patients undergoing OLT; Era I, 200 transplantations in 188 patients, and Era II, 355 transplantations in 339 patients. The donor mean age was 33.70 (Era I) versus 35.34 (Era II). Cause of death in both eras was traumatic brain injury followed by cerebral vascular accident. Organ recipient data showed a mean age of 48.87 (Era I) versus 46.49 (Era II). During Era I patients with Child B (56.8%) prevailed, followed by Child C (35.4%) and Child A (7.8%). In Era II also patients with Child B (53.1%) prevailed, followed by Child C (39.6%) and Child A (7.3%). The prevalence of hepatocellular carcinoma (HCC) during Era I was 9% (18) and in Era II 20% (71). The use of blood products in the perioperative period: was as follows packed red blood cells 1.76 (Era I) versus 0.57 (Era II) units; fresh frozen plasma 1.89 (Era I) versus 0.49 (Era II) units; platelets 2.16 (Era I) versus 0.28 (Era II) units; and cryoprecipitate 0.08 (Era I) versus 0.03 (Era II) units. OLT using the piggyback technique was performed with a transfusion rate below <30%, and it reduced blood loss and prevented severe hemodynamic instability.  相似文献   
10.
BackgroundPivotal ranolazine trials did not require optimization of conventional medical therapy including coronary revascularization and antianginal drug therapy prior to ranolazine use. This case series describes the use of ranolazine for the treatment of chronic stable angina refractory to maximal medical treatment in a veterans population.ResultsA total of 18 patients with a median age of 66 years were identified. All patients had prior percutaneous coronary intervention and/or coronary artery bypass graft surgery; 83% had three-vessel coronary artery disease, with left main disease present in 39% of patients. Prior to initiating ranolazine, antianginal use consisted of beta blockers (94%), long-acting nitrates (83%) and calcium channel blockers (61%). Median blood pressure (116.2/61.8 mmHg) and pulse (65 beats per min) were controlled. Median preranolazine angina episodes and sublingual nitroglycerin (SLNTG) doses per week were 14 and 10, respectively, with a Canadian Cardiovascular Society (CCS) angina grade of III–IV in 67% of patients. After initiation of ranolazine, median angina episodes per week and SLNTG doses used per week decreased to 0.7 and 0, respectively, with CCS grade of III–IV declining to 17%. Of the 18 subjects enrolled, 44% had complete resolution of angina episodes.ConclusionThe addition of ranolazine to maximally tolerated conventional antianginal drug therapy post coronary revascularization was associated with decreases in angina episodes and SLNTG utilization and improvement in CCS angina grades. Ranolazine may provide an effective treatment option for revascularized patients with refractory angina.  相似文献   
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