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71.
The involvement of the pulmonary vessels by tumour emboli may lead to a clinical picture defined as 'subacute cor pulmonale'. Information about this syndrome has been limited to case reports and a few series. A study of 214 autopsied cancer patients was undertaken to investigate the clinical signs and symptoms of tumour involvement of the pulmonary vessels (TIPV). The lungs were removed as a block and 15 sections (3 from each lobe) were analyzed. Clinical data about right ventricular failure, dyspnoea, cough, pleuritic chest pain, cyanosis, engorgement of jugular veins, peripheral oedema, haemoptysis and haemoptoic sputum were obtained from the medical records of each patient. Tumour emboli were detected in 89 cases, and no respiratory symptoms were recorded in 39. The presence of dyspnoea and cyanosis were highly significant in the group with TIVP, and right ventricular failure and peripheral oedema showed slight significant differences between the patients with and without TIPV. The classical picture of subacute cor pulmonale was observed in 13 patients and TIPV was considered to be the main cause of death in 29 cases. Our results indicate that although the development of subacute cor pulmonale was rare in patients with cancer, TIPV may be suspected when the patient presents respiratory distress and should be included in the differential diagnosis of dyspnoea in cancer patients.  相似文献   
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It was reviewed a series of 2860 cerebral computed tomography (CCT) in order to compare the main reasons at referral to investigation with the CCT results and the costs with normal and abnormal CCT. It was also studied the age and sex of the patients. Data were collected from one out of three diagnostic centers in Salvador, Brasil, for a three years period. The 2860 CCT exclude all investigation carried out for the follow-up of a previously diagnosed abnormality. CCT abnormalities were detected in 1152 (40.3%). The following reasons showed the highest proportion of abnormal CCT, for males and females respectively: demential syndrome (91.7 and 83.3%); cerebrovascular accidents (85.1 and 73.6%); infectious and parasitary diseases (76.5 and 78.6%); tumors (65.8 and 55.4%); and head injuries, 63.6% for males. In the female group, 65.0% of the CCT were normal, in a range of 65.0 to 80.0% for the age groups under 54 years old. In the male group, the highest proportion of normal CCT was found in the age groups: 25-34 (68.4%), < 15 (62.9%) and 35-44 (62.7%). The most common reasons for normal CCT for males and females were: headache (81.3 and 87.5%); dizziness/vertigo (79.3 and 78.6%); seizures (67.3 and 70.0%); psychomotor deficiency (72.0 and 67.7%) and "endocrine disorders", 75.0% for each sex. The highest proportion of normal CCT (65.3%) was requested by medical "convenios". The cost with normal CCT reached US$565,225 and with the abnormal ones, US$381,247. Costs with normal CCT were 2.2 higher for medical "convenios" as compared to those of the National Institute of Security requests and 2.8 more than those of private medicine.  相似文献   
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Protoplasts of the pathogenic plant fungus, Crinipellis perniciosa, were transformed to hygromycin B resistance using the pAN7-1 plasmid, which contains the Escherichia coli hph gene under the control of Aspergillus nidulans regulatory sequences. The pAN7-1 plasmid was introduced by PEG/CaCl(2) treatment. Transformation frequencies of 1.6-2.5 transformants/microg of DNA were achieved. About 54% of the transformants were abortive and 40 analyzed transformants were mitotically stable and showed different hygromycin B resistance levels. The presence of the hph gene was checked by PCR in five transformants and the integration of multiple plasmid copies into different genome sites was observed by Southern analysis. This is the first report of a C. perniciosa transformation system and represents an important step for further research into genetic manipulation of this fungal plant pathogen.  相似文献   
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The cytokines that predominate at the healthy maternal fetal interface are compatible with those produced by Th2/3 cells. Th1 and Th2 type immunity are mutually inhibitory and cytokine profiles are regulated in part by maternal sex steroids. The immune and endocrine equilibrium required for pregnancy success may be modified by external factors including stress, infection and altered maternal nutrition. The latter has received surprisingly little attention particularly as the effects of nutrition on immunity per se are widely documented. We have used animal models to investigate the effects of altered maternal diet on both immune and endocrine mechanisms important for pregnancy success. In rodents, maternal deficiencies in iron and vitamin A have been shown to negatively alter the expression of placental cytokines and in the case of vitamin A, increase placental apoptosis. In a highly controlled sheep model, overfeeding young growing females carrying singleton pregnancies restricts placental growth resulting in the premature delivery of low birth weight lambs. This is associated with reduced maternal concentrations of progesterone, placental lactogen, PSPB, GH and increased insulin, IGF-1, leptin and thyroid hormones (Wallace et al. Reprod 2001; 122:347–357). At day 80 of gestation (term=145) the placentae of overfed dams exhibit reduced expression of proliferation markers, predominantly in the fetal trophectoderm, and increased expression of the pro-apoptotic protein bax. These data indicate an altered balance between placental proliferation and apoptosis, possibly linked to maternal endocrine status. We conclude that maternal diet has considerable impact on immuno-endocrine mechanisms critical for pregnancy success.  相似文献   
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A nodular glomerulopathy characterized by mesangial deposits of monoclonal kappa light chains was detected by immunofluorescence in a renal biopsy from a patient with proteinuria and hypertension. These nodules lacked the tinctorial and morphologic features of amyloid. Ultrastructurally, the nodules contained electron-dense granular deposits as well as fibrils in parallel arrangement. The fibrils measured 110-140 A in diameter. They were consistent in size with amyloid fibrils. However, they differed in lacking the randomly oriented network of typical amyloid fibrils and more closely resembled fibrils intrinsic to mesangial matrix. The patient had no bone marrow or X-ray evidence of myeloma and no evidence of free monoclonal light chains in serum or concentrated urines. Biosynthetic studies of the patient's bone marrow cells demonstrated unbalanced immunoglobulin synthesis with excess production of monoclonal kappa light chains. These observations suggest that the observed glomerulopathy results from direct deposition of monoclonal light chains. Deposits with kappa light chain determinants have been found in 7 other patients with similar nodular glomerulopathies, 4 of whom had diagnosed clinical myeloma. The lesion of nonamyloidotic nodular glomerulopathy previously described in 19 patients, nor examined by immunopathologic techniques or not shown to contain light chain determinants, may have a similar pathogenesis.  相似文献   
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