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991.
Val-Bernal JF Gómez-Román JJ Vallina T Villoria F Mayorga M García-Arranz P 《Pathology, research and practice》1999,195(1):11-17
We investigated the presence of mucin in a series of 20 papillary renal cell carcinomas. Acid mucin was present in three cases (15%), in which basophilic mucin secretion was evident with hematoxylin-eosin. This secretion reacted positively with Mayer's mucicarmine, Alcian blue and high-iron diamine, but was negative for PAS in all the cases, indicating the presence of sulphomucins. We describe two different types of mucin secretion: luminal and intracytoplasmic. The secretion was abundant, diffuse or extensive, luminal in two cases and intracellular in numerous scattered tumor cells in one case. All tumors were < 3 cm in diameter (low grade, stage I). In the three mucin-secreting papillary tumors mentioned above, the immunohistochemical and lectin studies indicate both a proximal and a distal tubular staining pattern. Mucinous secretion in these tumors can be ascribed either to modulation or direct metaplasia of the tumor epithelium. Mucin production, despite its low frequency, can be considered an additional feature of papillary renal cell carcinoma. Thus, the presence of luminal or intracytoplasmic mucin deposition does not exclude papillary renal cell carcinoma from the differential diagnosis in cases of intra- or extrarenal carcinomas. 相似文献
992.
In order to determine whether the coselection observed between the selection trait (active avoidance behavior) of the Roman High Avoidance (RHA) and Roman Low Avoidance (RLA) rat lines and their neuroendocrine characteristics were genetically determined, we analyzed, in nonsegregating (RHA, RLA, and F1) and segregating (F2 and the two backcrosses) crosses, the inheritance pattern and the phenotypic correlations among behavioral (shuttle-box behavior), physiological (body, adrenal, and thymus weights), and neuroendocrine (corticosterone and prolactin reactivity, catecholamine enzyme activities) variables. Physiological characteristics and enzyme activities have acrucial role in sex dissociation. Avoidance behavior and prolactin reactivity to novel environment remained associated in segregating crosses despite gene rearrangement. They represented the most important variables to differentiate the Roman lines, perhaps sharing a common regulatory mechanism under genetic control. 相似文献
993.
The amygdala is part of the behavioural reinforcement system modulating long-term potentiation in rat hippocampus 总被引:1,自引:0,他引:1
Long-term potentiation (LTP) in the dentate gyrus can be modulated and prolonged by emotional/motivational influences when concurrently activated. A similar effect on LTP can be obtained by stimulating the amygdala, suggesting that this limbic structure might be part of the neural system involved in behavioural reinforcement. To confirm this we have performed a series of experiments in which the basolateral amygdala was either temporary inactivated by injection of lidocaine or permanently lesioned electrolytically. Both manipulations completely blocked the reinforcing effect of a motivational stimulus (drinking after 24-h deprivation) on LTP at the perforant pathway-dentate gyrus synapses, whilst leaving intact the non-reinforced potentiation. These results demonstrate that the basolateral amygdala is a key structure within the system involved in the modulatory interaction between the affective status of the animal and the mechanisms of functional plasticity. 相似文献
994.
995.
Genetic and clinical studies in autosomal dominant polycystic kidney disease type 1 (ADPKD1). 下载免费PDF全文
E Coto S Aguado J Alvarez M J Menéndez Díaz C López-Larrea 《Journal of medical genetics》1992,29(4):243-246
Thirteen Spanish families with autosomal dominant polycystic kidney disease were studied. In one family the disease did not segregate with polymorphic markers around the PKD1 locus. All subjects over the age of 30 years carrying a mutation at the PKD1 locus showed renal ultrasonographic cysts, but 40% of carriers of the PKD1 mutation younger than 30 years did not have renal cysts. Hypertension was found to be more frequent in those with renal cysts. Recombinants between 16p polymorphic loci and the PKD1 locus are described. 相似文献
996.
J E Alés-Martínez M Alvarez-Mon F Merino F Bonilla C Martínez A Durántez A De la Hera 《European journal of immunology》1988,18(11):1827-1830
While there is accumulating evidence to indicate the presence of functional abnormalities in T cells from aged healthy humans, their cellular basis remains unclear. By using two-color immunofluorescence and multiparameter flow cytometry we show that (a) the number of peripheral blood antigen receptor-positive (TcR-CD3+) T cells is significantly lower in aged than in young adults; (b) the numbers of E-rosette-forming (CD2+) cells are maintained in the elderly due to a reciprocal increase in the frequency of TcR-CD3- cells, which constitute only a minor lymphocyte subpopulation in young adults, and (c) TcR-CD3-CD2+5- lymphocytes exhibit the phenotypic features of natural killer (NK) cells. By using functional assays we show the TcR-CD3-CD2+16+ lymphocytes are indeed NK cells because they are activated by and lyse NK targets. In contrast, they are unresponsive to either phytohemagglutinin or mitogenic CD2 monoclonal antibody stimulation, which in turn activates TcR-CD3+CD2+16- T cells. We conclude that the increase in TcR-CD3-CD2+ NK cells masks the T cell reduction in aged humans by normalizing CD2+ cell frequencies. However, NK cells cannot functionally substitute the thymus-derived lymphocytes they replace. 相似文献
997.
Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献
998.
Immune response induction and new effector mechanisms possibly involved in protection conferred by the Cuban anti-meningococcal BC vaccine 下载免费PDF全文
Pérez O Lastre M Lapinet J Bracho G Díaz M Zayas C Taboada C Sierra G 《Infection and immunity》2001,69(7):4502-4508
This report explores the participation of some afferent mechanisms in the immune response induced by the Cuban anti-meningococcal vaccine VA-MENGOC-BC. The induction of delayed-type hypersensitivity in nursing babies and lymphocyte proliferation after immunization is demonstrated. The presence of gamma interferon IFN-gamma and interleukin-2 (IL-2) mRNAs but absence of IL-4, IL-5, and IL-10 mRNAs were observed in peripheral blood mononuclear cells from immunized subjects after in vitro challenge with outer membrane vesicles. In addition, some effector functions were also explored. The presence of opsonic activity was demonstrated in sera from vaccinees. The role of neutrophils as essential effector cells was shown. In conclusion, we have shown that, at least in the Cuban adult population, VA-MENGOC-BC induces mechanisms with a T-helper 1 pattern in the afferent and effector branches of the immune response. 相似文献
999.
Hemoperfusion study with carbamazepine in vitro 总被引:2,自引:0,他引:2
Derzsiová K Mydlík M Petríková V 《The International journal of artificial organs》1999,22(11):730-733
Sorption efficacy of active charcoal, Amberlite XAD-2 and Amberlite XAD-4 in hemoperfusion with carbamazepine was investigated in vitro. Authors carried out 15 hemoperfusions with carbamazepine in a closed system using the above mentioned sorbents; The perfusion solution used was 3,000 ml of 0.9% NaCl. The carbamazepine concentration in the solution was 52.5+/-3.0 mg/L. In addition, two in vitro hemoperfusions with carbamazepine using Amberlite XAD-2 sorbent and 1.500 ml of human plasma as a perfusion solution, were also performed. The concentration of carbamazepine in plasma was 50.4+/-1.2 mg/L. Individual hemoperfusions lasted 5 hours. Zero values of carbamazepine were achieved after 120 min of Amberlite XAD-2 or Amberlite XAD-4 hemoperfusion in 0.9% NaCl and after 240 min of hemoperfusion in human plasma. The results gathered suggest that the most effective in vitro hemoperfusion with carbamazepine was obtained with Amberlite XAD-2 or Amberlite XAD-4 and the least effective was with active charcoal. The authors recommend the use of hemoperfusion with Amberlite XAD-2 or Amberlite XAD-4 for acute intoxications with carbamazepine in humans. In addition, authors successfully performed 5-hour hemoperfusion using Amberlite XAD-4 in vivo, in an 18-year-old girl, who suffered from acute carbamazepine intoxication after a suicidal attempt. This treatment led to the rapid survival. 相似文献
1000.
López-Vázquez A Miña-Blanco A Martínez-Borra J Njobvu PD Suárez-Alvarez B Blanco-Gelaz MA González S Rodrigo L López-Larrea C 《Human immunology》2005,66(3):285-289
KIR and HLA loci are both highly polymorphic, and some HLA class 1 products bind and trigger cell-surface receptors specified by KIR genes. We examined whether KIR genes act in concert with HLA-B locus to control HIV-1 infection in a sample of Zambian patients. DNA samples from 88 Zambian patients with HIV-1 were examined. Patients were classified as either slow progressors (SP; n = 54) or rapid progressors (RP; n = 34) to AIDS. All were typed for HLA-B and KIR genes. Our results reveal an association between B*57 supertype (B*57s, which includes B*57 and B*58 alleles) and delayed progression to AIDS (p = 0.0007 by pc = 0.015; OR = 5.25). We also observed an increase incidence of Bw4-I80 in patients with slow progression (p = 0.001 by pc = 0.003, OR = 5). This increase was found to be secondary to B*57s. The presence of both KIR3DL1 and B*57S has a significant effect on progression to AIDS (p = 0.0008; OR = 5.61). B*57s genotypes with another HLA-B allele different from those in the trans position, which also had a specificity different to Bw4-I80 (Bw4-T80 or Bw6), was also greater in the SP than in the RP group (p = 0.00003; OR = 10.11). The presence of the inhibitory allele KIR3DL1 in combination with the HLA-B*57s alleles that contain the Bw4-I80 epitope, has a highly protective effect against progression to AIDS in Zambian patients. 相似文献