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排序方式: 共有3834条查询结果,搜索用时 15 毫秒
91.
Edjair V. Cabral Leucio D. Vieira Bruna R. M. Sant'Helena Valdilene S. Ribeiro Juliane S. Farias Regina S. Aires Silvania T. Paz Humberto Muzi‐Filho Ana D. Paixo Adalberto Vieyra 《Clinical and experimental pharmacology & physiology》2019,46(12):1151-1165
Maternal salt overload programs cardiovascular and renal alterations in the offspring. However, beneficial and harmful effects of high dose vitamin E supplementation have been described in humans and animals. We investigated the hypothesis as to whether cardiac and renal alterations can be programmed by gestational salt overload, and can become further modified during lactation and after weaning. Male Wistar rats were used, being the offspring of mothers that drank either tap water or 0.3 mol/L NaCl for 20 days before and during pregnancy. α‐Tocopherol (0.35 g/kg) was administered to mothers daily during lactation or to their offspring for 3 weeks post‐weaning. Systolic blood pressure (tcSBP) was measured in juvenile rats aged 210 days. The response of mean arterial pressure (MAP) and heart rate (HR) to intravenous infusion of angiotensin II (Ang II) was also examined. Left ventricle plasma membrane (PMCA) and sarcoplasmic reticulum Ca2+‐ATPase (SERCA) activities, and certain parameters of renal function, were measured. Maternal saline programmed for increased body mass and kidney mass/body mass ratio, increased tcSBP, increased mean arterial pressure and heart rate with anomalous response to infused Ang II. In the heart, saline increased PMCA and α‐Tocopherol per se increased PMCA/SERCA. In the kidney, the most remarkable result was the silent saline programming of CrCl, which was sensitized for a sharp decrease after α‐Tocopherol. In conclusion, the combination of maternal saline overload and high α‐Tocopherol immediately after birth leads to simultaneous cardiovascular and renal alterations in the young offspring, like those encountered in type V cardiorenal syndrome. 相似文献
92.
目的 观察肢带型肌营养不良的MRI表现。方法 回顾性分析7例经临床及病理检查确诊为肢带型肌营养不良患者的MRI资料,观察双侧大腿肌群脂肪沉积与炎性水肿情况,采用4分法进行评价。并进行统计学分析。结果 肢带型肌营养不良患者大腿肌群MRI均可见脂质沉积和炎性水肿性改变。不同肌肉间脂肪沉积(χ2=75.596,P<0.01)与炎性水肿差异均有统计学意义(χ2=41.368,P<0.01),双侧大腿肌群间脂肪沉积与炎性水肿差异均无统计学意义(P均>0.05)。结论 肢带型肌营养不良患者大腿肌群MRI信号特点及分布具有一定特征,MR检查有助于疾病的诊断。 相似文献
93.
A. R. Cabral L. A. Cole D. A. Walz C. W. Castor 《Arthritis \u0026amp; Rheumatology》1987,30(12):1393-1400
Connective tissue activating peptide—V (CTAP-V) is a single-chain, mesenchymal cell—derived anionic protein with large and small molecular forms (Mr of 28,000 and 16,000, respectively), as defined by sodium dodecyl sulfate—polyacrylamide gel electrophoresis. The proteins have similar specific activities with respect to stimulation of hyaluronic acid and DNA formation in human synovial fibroblast cultures. S-carboxymethylation or removal of sialic acid residues did not modify CTAP-V biologic activity. Rabbit antibodies raised separately against each of the purified CTAP-V proteins reacted, on immunodiffusion and on Western blot, with each antigen and neutralized mitogenic activity. The amino-terminal amino acid sequence of the CTAP-V proteins, determined by 2 laboratories, confirmed their structural similarities. The amino-terminal sequence through 37 residues was demonstrated for the smaller protein. The first 10 residues of CTAP-V (28 kd) were identical to the N-terminal decapeptide of CTAP-V (16 kd). The C-terminal sequence, determined by carboxy-peptidase Y digestion, was the same for both CTAP-V molecular species. The 2 CTAP-V peptides had similar amino acid compositions, whether residues were expressed as a percent of the total or were normalized to mannose. Reduction of native CTAP-V protein released sulfhydryl groups in a protein:disulfide ratio of 1:2; this suggests that CTAP-V contains 2 intramolecular disulfide bonds. Clearly, CTAP-V is a glycoprotein. The carbohydrate content of CTAP-V (16 kd) and CTAP-V (28 kd) is 27% and 25%, respectively. CTAP-V may have significance in relation to autocrine mechanisms for growth regulation of connective tissue cells and other cell types. 相似文献
94.
We previously identified, in normal urine, a growth factor that stimulated monolayer cultures of human synovial, cartilage, and dermal fibroblasts to synthesize incremental amounts of hyaluronic acid, proteoglycans, and DNA. An isolation procedure guided by bioassays and immunologic methods disclosed 2 anionic bioactive polypeptides with Mr of 28,000 and 16,000, respectively, as judged by single bands with sodium dodecyl sulfate—polyacrylamide gel electrophoresis in reduced and nonreduced samples. Rabbit antibodies raised against each purified protein were shown to react, on immunodiffusion and Western blot, with both antigens. Immunohistochemical and immunobinding studies detected the protein in normal human synovial, dermal, and cartilage fibroblasts and in human saphenous vein endothelial cells. The mesenchymal cell—derived growth factor is now designated connective tissue activating peptide—V (CTAP-V). Monospecific polyclonal anti—CTAP-V antibodies were used in a radial immunodiffusion assay for quantitative determination of the antigen in biologic fluids. In normal human plasma the concentration of CTAP-V was below the limit of detection. The CTAP-V concentration in normal urine was 4.5 ± 2.0 m̈g/ml, calculated from measurements of 5—18-fold concentrated samples. Joint fluid from patients with rheumatic diseases and normal renal function had CTAP-V levels similar to those found in plasma; 2—15-fold increases were detected in plasma and joint fluid of patients with chronic renal failure. Immunodiffusion or dot-blot analysis revealed a CTAP-V—like material in the plasma or serum of 10 mammalian species. It was not detectable in 2 avian species. 相似文献
95.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献96.
97.
M Okano DA Harn Jr M Abe MM Wang AR Satoskar K Nishizaki Y Masuda M Okano T Yoshino 《Allergy》1999,54(6):593-601
BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated. 相似文献
98.
Maicon Oliveira Miranda Wesley Eullio Cabral Cavalcanti Felipe Fernandes Barbosa Jos Antonio de Sousa Francisco Ivan da Silva Sibele B. C. Pergher Tiago Pinheiro Braga 《RSC advances》2021,11(44):27720
The present work studied ibuprofen degradation using titanium dioxide as a photocatalyst. Mechanistic aspects were presented and the preferred attack sites by the OH˙ radical on the ibuprofen molecule were detailed, based on experimental and simple theoretical-computational results. Although some previous studies show mechanistic proposals, some aspects still need to be investigated, such as the participation of 4-isobutylacetophenone in the ibuprofen degradation and the preferred regions of attack by OH˙ radicals. The photodegradation was satisfactory using 0.03 g of TiO2 and pH = 5.0, reaching 100% decontamination in 5 min. The zeta potential curve showed the regions of attraction and repulsion between TiO2 and ibuprofen, depending on the pH range and charge of the species, influencing the amount of by-products formed. Different by-products have been identified by GC-MS, such as 4-isobutylacetophenone. Ibuprofen conversion to 4-isobutylacetophenone takes place through decarboxylation reaction followed by oxidation. The proposed mechanism indicates that the degradation of ibuprofen undergoes a series of elementary reactions in solution and on the surface. Three different radicals (OH˙, O2−˙ and OOH˙) are produced in the reaction sequence and contribute strongly to the oxidation and mineralization of ibuprofen and by-products, but the hydroxyl radical has a greater oxidation capacity. The simple study using the DFT approach demonstrated that the OH˙ radical attacks preferentially in the region of the ibuprofen molecule with high electronic density, which is located close to the aromatic ring (C C bond). The presence of the OH˙ radical was confirmed through a model reaction using salicylic acid as a probe molecule.The degradation of ibuprofen undergoes a series of elementary reactions, generating different radicals which attack preferentially in the region of the ibuprofen with high electron density. 相似文献
99.
目的 探讨保乳手术联合腔镜腋窝淋巴结清扫术(MALND)对乳腺癌患者上肢功能、应激反应及血管细胞黏附分子-1 (VCAM-1)、细胞间黏附分子-1(ICAM-1)水平的影响。方法 回顾性分析98例乳腺癌患者的临床资料,依据手术方式的不同分为研究组53例和对照组45例。对照组行保乳手术联合传统腋窝淋巴结清扫术(CALND),研究组行保乳手术联合MALND。比较2组术前、术后6个月上肢功能;收集2组患者术前、术后12 h焦虑自评量表(SAS)、抑郁自评量表(SDS)评分以及心率(HR)、平均动脉压(MAP)水平,并对比2组应激反应程度;比较2组患者术前、术后5 d VCAM-1、ICAM-1水平。结果 术后6个月,研究组前屈、后伸、内收、外展、内旋、外旋活动角度大于对照组,差异有统计学意义(P<0.05);术后12 h,研究组SAS、SDS评分及HR、MAP水平低于对照组,差异有统计学意义(P<0.05);术后5 d,研究组VCAM-1、ICAM-1水平低于对照组,差异有统计学意义(P<0.05)。结论 保乳手术联合MALND对乳腺癌患者上肢功能影响小,术后应激反应程度轻... 相似文献
100.
M.?OleastroEmail author M.?Gerhard A.?I.?Lopes P.?Ramalho J.?Cabral A.?Sousa Guerreiro L.?Monteiro 《European journal of clinical microbiology & infectious diseases》2003,22(2):85-91
The aim of this study was to evaluate the prevalence of virulence genotypes, namely cagA, vacA and babA2, of Helicobacter pylori strains isolated from Portuguese adults and children presenting gastroduodenal pathology. One hundred thirty-six strains
were studied, 82 isolated from adult patients (50 with nonulcerative gastritis and 32 with active peptic ulcer) and 58 isolated
from children (54 with nonulcerative gastritis and 4 with duodenal ulcer). Genotyping of cagA, vacA and babA2 was assessed by polymerase chain reaction. Overall, Helicobacter pylori strains carrying more virulent genotypes were much more prevalent in adults than in children, particularly the type I (vacAs1- and cagA-positive) and the triple-positive (vacAs1-, cagA- and babA2-positive) strains (P<0.001). A subpopulation of adults and children with nonulcerative gastritis was also studied, and differences in the prevalence
of virulent genotypes were observed, either for individual genotypes (P=0.017 for cagA, P=0.010 for vacAs1) or in combinations, i.e. the type I genotype (P=0.005) and the triple-positive strains (P=0.031). There was no difference between the two populations in the distribution of babA2 and m1/m2 genotypes. Considering the cohort effect in the epidemiology of Helicobacter pylori infection, these results suggest that different strains might circulate during different periods of time, or that, after
infection in childhood, individual strains will undergo changes during the course of infection.
Electronic Publication 相似文献