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61.
Purification of thymus mRNA coding for a 16,000-dalton polypeptide containing the thymosin alpha 1 sequence. 总被引:1,自引:1,他引:1
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![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M Freire E Hannappel M Rey J M Freire H Kido B L Horecker 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(1):192-195
A mRNA fraction purified by preparative polyacrylamide disc gel electrophoresis from calf thymus polysomes codes for a polypeptide(s) having a mass of 16,000-17,000 daltons. This polypeptide contains amino acid sequences corresponding to residues 11-18 and 19-25 of thymosin alpha 1. The yield of the octapeptide indicates that the 16,000-dalton peptide is the major product formed in the cell-free synthesis system containing the purified mRNA. 相似文献
62.
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels. 相似文献
63.
64.
Randomized Clinical Trial of Four Adhesion Strategies in Posterior Restorations—18‐Month Results
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![点击此处可从《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Flávia B. Delbons DDS MS PhD Jorge Perdigão DMD MS PhD Edson Araujo DDS MS PhD Charles A. Melo Freire DDS Danilo D. Caldas DDS MS PhD Jorge L. Cardoso DDS Margarida Pagani DDS Gilberto A. Borges DDS MS PhD Rodrigo B. Lima DDS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2015,27(2):107-117
65.
RC Baker RAJ Spence M Boohan A Dorman M Stevenson SJ Kirk K McGlade 《The Ulster medical journal》2015,84(1):30-36
Background:
Undergraduate surgery is at an important crossroads. Many departments report significant difficulties delivering effective teaching. Our student feedback indicated a dated surgical curriculum lacking structure, quality and uniformity. We report on a new ”blended” approach employing a combination of professional DVDs, case based discussions, online material and traditional bedside teaching designed to provide structure, standardization, and equality of learning .Methods:
Year 4 students who had undertaken the new course and year 5 students who had participated in the traditional teaching programme were compared. Students completed a 20 item questionnaire about their experiences of the surgical teaching programme.Results:
One hundred and seventy-one year 4 (70%) and148 year 5 students (66%) responded. Domains relating to “Overall Satisfaction with the course”, “Approval of innovative teaching methods and interactivity” and “Satisfaction with the clarity of course information” showed improvements when comparing the new and old programmes. However bedside teaching was not rated as highly in the new programme (p<0.05).Conclusion:
This blended approach has resulted in improved student understanding and engagement. The apparent compromise of bedside teaching may be a reflection of higher expectations. We believe that a similar blended approach has the potential to re-invigorate surgical teaching elsewhere. 相似文献66.
Alana Freire de Azevedo Jorge Luís de Lisboa Dutra Micheli Luize Barbosa Santos Darlisson de Alexandria Santos Péricles Barreto Alves Tatiana Rodrigues de Moura Roque Pacheco de Almeida Marcelo Ferreira Fernandes Ricardo Scher Roberta Pereira Miranda Fernandes 《Parasitology research》2014,113(1):19-27
Fatty acids, especially those from phospholipids (PLFA), are essential membrane components that are present in relatively constant proportions in biological membranes under natural conditions. However, under harmful growth conditions, such as diseases, environmental changes, and chemical exposure, the fatty acid proportions might vary. If such changes could be identified and revealed to be specific for adverse situations, they could be used as biomarkers. Such biomarkers could facilitate the identification of virulence and resistance mechanisms to particular chemotherapeutic agents. Therefore, specific biomarkers could lead to better therapeutic decisions that would, in turn, enhance treatment effectiveness. The objective of this study was to compare the fatty acid profiles of trivalent antimony and nitric oxide (NO)-resistant and -sensitive Leishmania chagasi and Leishmania amazonensis isolates. Fatty acid methyl esters (FAMEs) were obtained from total lipids (MIDI), ester-linked lipids (ELFA), and ester-linked phospholipids (PLFA). FAMEs were analyzed by chromatography and mass spectrometry. Species- or resistance-associated differences in FAME profiles were assessed by nonmetric multidimensional scaling, multiresponse permutation procedures, and indicator species analyses. The isolate groups had different MIDI-FAME profiles. However, neither the ELFA nor PLFA profiles differed between the sensitive and resistant isolates. Levels of the fatty acid 18:1 Δ9c were increased in sensitive isolates (p?<?0,001), whereas the fatty acid 20:4 Δ5,8,11,14 showed the opposite trend (p?<?0.01). We conclude that these two fatty acids are potential biomarkers for NO and antimony resistance in L. chagasi and L. amazonensis and that they could be helpful in therapeutic diagnoses. 相似文献
67.
Objective:To investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric medicine.Methods:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant extract.For the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),orally.This w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or non-mortality.Incision wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under anesthesia.The first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,respectively.Results:The percentage yield of the extract was 49.80%w/w dry matter.The phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,perpenoids.saponins,steroids,proteins,and carbohydrates.The LD_(50) was beyond our experimental limit and was not determined.Increased concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,P0.05) healing effect on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:These data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine. 相似文献
68.
Watanabe E Diniz LR da Mota LM Barros SM de Carvalho JF 《Rheumatology international》2012,32(6):1855-1857
Juvenile idiopathic arthritis (JIA) is characterized by the typical joint involvement and some patients have extra-articular lesions, such as uveitis and pleuritis. However, until this date, no case of alveolar hemorrhage in JIA has been described. Herein, the authors describe a case of a male patient, 33?years old diagnosed as polyarticular JIA who had a dramatic evolution with alveolar hemorrhage secondary to pulmonary capillaritis. He received intravenous immunoglobulin and pulse therapies with glucocorticoid and cyclophosphamide with a satisfactory outcome. In addition, the authors review this important pulmonary complication in rheumatic diseases. 相似文献
69.
de Andrade DC de Magalhães Souza SC de Carvalho JF Takayama L Borges CT Aldrighi JM Pereira RM 《Rheumatology international》2012,32(6):1549-1553
Bone mass was only previously studied in juvenile dermatomyositis/polymyositis (DM/PM) patients. Therefore, the objective this study was to evaluate the prevalence of osteoporosis and fractures in adult DM/PM. Forty female DM/PM and 78 age-, gender-, and BMI-matched healthy controls were studied. Medical charts and clinical interviews of all patients were evaluated for demographic and clinical data, including disease activity, cumulative doses of glucocorticoid, menarche and menopause age, and fractures. Bone mineral density (BMD) using dual X-ray absorptiometry (DXA) were measured at lumbar spine (L1–L4) and hip. A decreased BMD in lumbar spine [0.902 (0.136) vs. 0.965 (0.141) g/cm2, P?=?0.022] and femoral neck [0.729 (0.12) vs. 0.784 (0.127) g/cm2, P?=?0.027] was observed in patients compared to controls. In addition, osteoporosis was more frequent in patients than in controls in both lumbar spine (20 vs. 3.8%, P?=?0.007) and the femoral neck (27.5 vs. 10.3%, P?=?0.016). Moreover, a high prevalence of fractures was found in patients in comparison to healthy subjects (17.9 vs. 5.1%, P?=?0.040; OR?=?3.92; CI 95%:1.07–14.33). Comparing DM/PM patients with (n?=?17) and without (n?=?23) osteoporosis/fractures, significant differences were observed regarding age [56.8 (11.9) vs. 48.3 (13.2) years, P?=?0.042], weight [62.05 (13.56) vs. 71.51 (11.46) kg, P?=?0.022] and frequency of post menopausal women (94.1 vs. 65.2%, P?=?0.0002). No differences were observed concerning height, lean mass, total fat mass, disease activity, mean value of creatine kinase, cumulative glucocorticoid dose, or bisphosphonate use. Logistic regression analysis revealed a negative association between the presence of osteoporosis/fractures and weight (OR: 0.92, 95% CI: 0.85–0.98; P?=?0.016). This is the first study that analyzed bone mass in adult DM/PM patients and it demonstrated that about one quarter of these patients have osteoporosis/fracture. 相似文献
70.
Pollyanna d’ávila Leite Jozélio Freire de Carvalho 《Rheumatology international》2012,32(10):3265-3268
The antiphospholipid syndrome (APS) can be primary, when it occurs alone, or secondary, when it is associated with another autoimmune disease, mainly systemic lupus erythematosus and rarely other autoimmune diseases. Cases described in literature (Medline 1966 to December 2009) associate the presence of antiphospholipid antibodies with the presence of APS and systemic sclerosis (SS). Currently, however, no cases of the SS variant sine scleroderma with APS have been described. In this study, the authors describe the case of a patient with APS characterised by thrombosis of the retinal veins, in May 2006, the presence of lupus anticoagulant and an anticardiolipin IgG antibody. In May 2007, this patient developed Raynaud’s phenomenon, a lack of oesophageal motility and nailfold capillaroscopy with a scleroderma pattern. The patient was positive for the anti-centromere antibody but lacked any evidence of cutaneous thickening or involvement. In summary, the authors describe the first case of a patient with APS associated with SS sine scleroderma. 相似文献