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1.
Sci Rep ; 12(1): 11076, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35773293

RESUMO

For effective cutting tool inserts that absorb thermal shock at varying temperature gradients, improved thermal conductivity and toughness are required. In addition, parameters such as the coefficient of thermal expansion must be kept within a reasonable range. This work presents a novel material design framework based on a multi-scale modeling approach that proposes nickel (Ni)-reinforced alumina (Al2O3) composites to tailor the mechanical and thermal properties required for ceramic cutting tools by considering numerous composite parameters. The representative volume elements (RVEs) are generated using the DREAM.3D software program and the output is imported into a commercial finite element software ABAQUS. The RVEs which contain multiple Ni particles with varying porosity and volume fractions are used to predict the effective thermal and mechanical properties using the computational homogenization methods under appropriate boundary conditions (BCs). The RVE framework is validated by the sintering of Al2O3-Ni composites in various compositions. The predicted numerical results agree well with the measured thermal and structural properties. The properties predicted by the numerical model are comparable with those obtained using the rules of mixtures and SwiftComp, as well as the Fast Fourier Transform (FFT) based computational homogenization method. The results show that the ABAQUS, SwiftComp and FFT results are fairly close to each other. The effects of porosity and Ni volume fraction on the mechanical and thermal properties are also investigated. It is observed that the mechanical properties and thermal conductivities decrease with the porosity, while the thermal expansion remains unaffected. The proposed integrated modeling and empirical approach could facilitate the development of unique Al2O3-metal composites with the desired thermal and mechanical properties for ceramic cutting inserts.

2.
J Nematol ; 50(3): 329-342, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30451418

RESUMO

Conservation agriculture (CA) based on the principles of minimum soil disturbance, crop residue retention, and crop rotation has been the focus of intensive research in recent years. A study was carried out to determine the effects of tillage and fertilizer on the population densities of plant-parasitic nematodes in maize. Three tillage regimes, (i) basin planting, (ii) rip line seeding, and (iii) conventional tillage, were combined with four fertilizer regimes: (i) no-fertilizer, (ii) low fertilizer rate, (iii) medium fertilizer rate, and (iv) high fertilizer rate. The experiment was arranged as a split plot in randomized complete block design, replicated three times with tillage as the main plot factor and fertilizer as the sub-plot factor. The study was conducted on fine-textured Cambisol soils at Chinhoyi University of Technology farm, Zimbabwe, over two cropping seasons between December 2014 and April 2016. Eight plant-parasitic nematode genera were observed belonging to five groups based on their feeding sites: (i) sedentary endoparasites ( Meloidogyne and Rotylenchulus ), (ii) migratory endoparasites ( Pratylenchus ), (iii) semi-endoparasites ( Scutelonema and Helicotylenchus ), (iv) ectoparasites ( Xiphinema and Trichodorus ), and (v) algal, lichen or moss feeders ( Tylenchus ). In both cropping seasons, semi-endoparasitic nematodes were double under rip line seeding and triple under basin planting compared to conventional tillage. Basin planting had higher plant-parasitic nematode richness than rip line seeding. Nematode densities did not have a measurable effect on maize grain yield. Maize grain yield was higher in rip line seeding (37%) and planting basins (52%) than conventional tillage during 2014/15 cropping season. On the other hand, during 2015/16 cropping season, maize grain yield was 78% and 113% higher in rip line seeding and basin planting, respectively, compared to conventional tillage. The results show that under the environmental and edaphic conditions of this specific study site, semi-endoparasitic nematodes were higher under rip line seeding and basin planting compared to conventional tillage. The authors conclude that (i) plant-parasitic nematode genera exhibited differential responses to different tillage systems but were not affected by fertilizer application, and (ii) in the present study, maize grain yield response under different tillage and fertilizer regimes was overall not related to nematode population density and composition.

3.
J Perinatol ; 35(10): 832-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26226248

RESUMO

OBJECTIVE: To assess the effect of early clamping and milking of a 40-cm umbilical cord LUCM (long umbilical cord and milking) on hemoglobin (Hb) and serum ferritin concentrations at 6 months of age and to evaluate whether the effect is different in infants of anemic and non-anemic mothers. STUDY DESIGN: Eligible term-infants of anemic (maternal Hb<11.0 g dl(-1)) and non-anemic mothers (Hb ⩾11.0 g dl(-1)) were randomized to LUCM or control groups (N=100 each). In the LUCM group, the umbilical cord was clamped at 40-cm length and milked. The control group had the cord clamped at 5 cm and not milked. Neonatal morbidities until discharge and Hb and serum ferritin at 6 months of age were compared. Effects in infants of anemic and non-anemic mothers were compared. RESULT: Compared with infants of non-anemic mothers, cord Hb was similar (14.50±1.90 g dl(-1) vs 14.67±1.73 g dl(-1)), but cord ferritin lower (85.8±55.4 ng ml(-1) vs 119.4±58.5 ng ml(-1), P<0.01) in infants of anemic mothers. Mean Hb concentration at 6 months was 9.60±1.42 g dl(-1) in the LUCM group and 9.07±1.10 g dl(-1) in the control group (P=0.004). Mean serum-ferritin concentration at 6 months was 113.9±43.8 ng ml(-1) in the LUCM group and 70.8±39.5 ng/ml in the control group (P<0.001). The effectiveness of LUCM did not vary with the maternal anemia status. CONCLUSION: Keeping the umbilical cord long and milking may be an effective method for improving Hb and iron stores at 6 months of age in term-infants.


Assuntos
Anemia Ferropriva/diagnóstico , Ferritinas/sangue , Hemoglobinas/análise , Período Pós-Parto/sangue , Nascimento a Termo/sangue , Cordão Umbilical/irrigação sanguínea , Adulto , Animais , Constrição , Feminino , Humanos , Índia , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Projetos Piloto , Fatores de Tempo , Adulto Jovem
4.
AoB Plants ; 62014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25139769

RESUMO

Salinization is increasing on a global scale, decreasing average yields for most major crop plants. Investigations into salt resistance have, unfortunately, mainly been focused on conventional crops, with few studies screening the potential of available halophytes as new crops. This study has been carried out to investigate the mechanisms used by quinoa, a facultative halophytic species, in order to cope with high salt levels at various stages of its development. Quinoa is regarded as one of the crops that might sustain food security in this century, grown primarily for its edible seeds with their high protein content and unique amino acid composition. Although the species has been described as a facultative halophyte, and its tolerance to salt stress has been investigated, its physiological and molecular responses to seawater (SW) and other salts have not been studied. We evaluated the effects of SW and different salts on seed germination, seedling emergence and the antioxidative pathway of quinoa. Seeds were germinated in Petri dishes and seedlings grown in pots with SW solutions (25, 50, 75 and 100 %) and NaCl, CaCl2, KCl and MgCl2 individually, at the concentrations in which they are present in SW. Our results demonstrated that all salts, at lower concentrations, increased the germination rate but not the germination percentages, compared with control (pure water). Conversely, seedlings were differently affected by treatments in respect to salt type and concentration. Growth parameters affected were root and shoot length, root morphology, fresh and dry weight, and water content. An efficient antioxidant mechanism was present in quinoa, activated by salts during germination and early seedling growth, as shown by the activities of antioxidant enzymes. Total antioxidant capacity was always higher under salt stress than in water. Moreover, osmotic and ionic stress factors had different degrees of influence on germination and development.

5.
East Mediterr Health J ; 16(10): 1025-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21222417

RESUMO

The aim of this study was to analyse results of the pilot screening round for Al-Qassim Screening Mammography Programme and compare with international standards. Analysis was conducted in the central screening office in Prince Faisal Oncology Centre, which coordinates activities of various screening units. Data were collected during the period 1 January 2007 to 30 June 2008. Organizational and functional information was obtained from policy and procedure manuals of the programme. Out of 9812 eligible women, 1766 (18%) participated and data were available for 1628 (16.6%). The median age of participants was 47 (standard deviation 8.12) years. The low uptake rate (18%) and a high recall rate (31.6%) characterized the pilot screening round. Biopsy rate was 1.5% and cancer detection rate was 0.24%. Many performance indicators in this pilot screening round were not available. Many of the available indicators did not meet international standards.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia , Programas de Rastreamento/organização & administração , Adulto , Idoso , Algoritmos , Biópsia/estatística & dados numéricos , Neoplasias da Mama/epidemiologia , Institutos de Câncer , Árvores de Decisões , Feminino , Humanos , Mamografia/métodos , Mamografia/estatística & dados numéricos , Pessoa de Meia-Idade , Modelos Organizacionais , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Projetos Piloto , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Indicadores de Qualidade em Assistência à Saúde , Arábia Saudita/epidemiologia
6.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117998

RESUMO

The aim of this study was to analyse results of the pilot screening round for Al-Qassim Screening Mammography Programme and compare with international standards. Analysis was conducted in the central screening office in Prince Faisal Oncology Centre, which coordinates activities of various screening units. Data were collected during the period 1 January 2007 to 30 June 2008. Organizational and functional information was obtained from policy and procedure manuals of the programme. Out of 9812 eligible women, 1766 [18%] participated and data were available for 1628 [16.6%]. The median age of participants was 47 [standard deviation 8.12] years. The low uptake rate [18%] and a high recall rate [31.6%] characterized the pilot screening round. Biopsy rate was 1.5% and cancer detection rate was 0.24%. Many performance indicators in this pilot screening round were not available. Many of the available indicators did not meet international standards


Assuntos
Programas de Rastreamento , Neoplasias da Mama , Detecção Precoce de Câncer , Projetos Piloto , Mamografia
7.
J Clin Gastroenterol ; 28(3): 233-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10192609

RESUMO

The authors studied the relationship of endoscopic esophagitis and gastroesophageal flap valve (GEFV) in patients with symptomatic gastroesophageal reflux (GER). On endoscopy, the GEFV was graded as I to IV in 138 patients with acid regurgitation and heartburn relieved by antacids, and in 54 control subjects without symptoms suggestive of GER. Grade of GEFV was correlated with the grade of esophagitis, response to medical treatment, duration of symptoms, obesity, smoking, sex, and age of the patient. Abnormal GEFV (grades III and IV) was more frequent in patients with symptomatic GER, both with and without esophagitis, compared with control subjects (p = 0.000001. p = 0.03). Abnormal GEFV was significantly more common in patients with GER with esophagitis compared with those without (p < 0.00001). There was no significant difference in the distribution of normal and abnormal GEFV in patients with grade I esophagitis. However, grade 2 and grade 3 esophagitis were associated more commonly with an abnormal GEFV (p < 0.00001, p < 0.02 respectively). Hiatal hernia is always associated with an abnormal GEFV. Abnormal GEFV correlated significantly with age (more frequent when older than 40 years). Sex, duration of symptoms (>3 years), response to medical therapy, smoking, and obesity (body mass index > 30 kg/m2) did not correlate significantly with abnormal GEFV. We conclude that endoscopic esophagitis is usually associated with abnormal GEFV. It is more frequent in grades 2 and 3 but not grade 1 esophagitis. It is also encountered more commonly after the age of 40 years.


Assuntos
Endoscopia do Sistema Digestório , Esofagite/diagnóstico , Junção Esofagogástrica/patologia , Adulto , Diagnóstico Diferencial , Esofagite/complicações , Feminino , Seguimentos , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/diagnóstico , Hérnia Hiatal/complicações , Hérnia Hiatal/diagnóstico , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
8.
Cancer ; 81(5): 277-80, 1997 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-9349514

RESUMO

BACKGROUND: Fine-needle aspiration biopsy (FNAB) is an important tool for the cytologic assessment of patients with lymphadenopathy. The nonaspiration method (without the use of a syringe or a handle), or fine-needle capillary biopsy (FNCB), is becoming popular for its ease of learning and use. The authors compared the two techniques of fine-needle biopsy (with and without aspiration) for identifying the cause of superficial lymphadenopathy. METHODS: Over a 2-year period 50 cytologic examinations were conducted in patients with superficial lymphadenopathy. Both procedures were performed at the same site; the order in which they were performed was determined randomly. Slides were fixed in a similar manner and examined by a cytotechnologist and pathologists blind to the procedure. Scores were tabulated and compared and diagnosis was confirmed by histologic examination. RESULTS: The best and the average score for the yield of cellular material was higher with FNCB (P < 0.004). Cell preservation also was superior with FNCB (P = 0.00066). However, the failure rate was lower with FNAB (P = 0.7662). CONCLUSIONS: FNCB of superficial lymph nodes yields adequate cellular material of superior quality, which may be advantageous in certain situations. However, the diagnostic yield does not appear to be significantly increased using this technique.


Assuntos
Biópsia por Agulha/métodos , Doenças Linfáticas/patologia , Adolescente , Adulto , Axila , Humanos , Linfonodos/patologia , Pescoço , Sucção
9.
Ann Saudi Med ; 17(6): 595-600, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17338003

RESUMO

Regional differences in the pattern of cancer are obvious in Saudi Arabia. From January 1987 to December 1995, 1106 new cases of cancer (642 males, 464 females) were seen at the King Fahd Specialist Hospital in Buraidah, Al-Qassim. Overall, lymphomas, non-Hodgkin's and Hodgkin's disease combined were the most common malignancy seen (15.10%), followed by esophageal carcinoma (7.77%). Thyroid cancer was the most common malignancy among females (12.50%), followed by breast cancer (9.48%). The majority of the patients were in the younger age group (77% were <50 years of age). Among the hematological malignancies, acute lymphoblastic leukemia was the most frequent type (36.23%). Lymphomas were the most common malignancy (66.12%) seen in the pediatric age group (0-14 years), followed by leukemias and brain tumors. The pattern of cancer in Al-Qassim is generally similar to other regions of Saudi Arabia, with few regional variations. prominent among such variations is the high frequency of non-Hodgkin's lymphomas (NHL), esophageal and thyroid carcinomas.

10.
Tumori ; 82(5): 505-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9063536

RESUMO

5-fluorouracil cardiotoxicity is increasingly recognized with variable presentation. We report a patient who developed cardiogenic shock due to high-dose 5-fluorouracil infusion (1,000 mg/m2 every 24 hr for 96 hr). There was no evidence of myocardial necrosis. The patient recovered completely without any residual cardiac dysfunction. The exact cause of 5-fluorouracil toxicity remains to be determined. The case highlights the need for careful monitoring of patients who receive high-dose 5-fluorouracil for the development of cardiotoxicity.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Fluoruracila/efeitos adversos , Choque Cardiogênico/induzido quimicamente , Adulto , Antimetabólitos Antineoplásicos/administração & dosagem , Eletrocardiografia , Humanos , Infusões Intravenosas , Masculino , Choque Cardiogênico/fisiopatologia
14.
Oncology ; 50(6): 441-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8233284

RESUMO

Cardiotoxicity with 5-fluorouracil (5-FU) therapy has been reported to range from asymptomatic EKG abnormalities to fatal myocardial infarction. We report a prospective study in 100 consecutive patients receiving 5-FU infusion in combination with other chemotherapeutic agents or alone for the treatment of different malignancies with the aim of identifying patients who develop symptomatic cardiotoxicity. Patients with a history of cardiac illness, abnormal EKG or cardiac enzyme levels were excluded. Patients were observed during the total period of infusion, daily EKG was performed on asymptomatic patients, those who developed cardiotoxicity were monitored till symptom-free for 24 h. Eight patients developed symptoms suggestive of cardiotoxicity. Pain was the commonest symptom (5/8), followed by palpitation and sweating. Three patients developed EKG abnormalities and 1 went into cardiogenic shock. Time to toxicity ranged from 18 to 30 h (mean 24 +/- 3.7 h) and serial cardiac enzyme levels remained normal in all patients. The symptoms reversed immediately on cessation of the treatment in most of the patients (7/8). Time to recovery ranged from 5 to 60 min (mean 19.28 +/- 19.6 min). There was no recorded death due to toxicity. We conclude that 5-Fu infusion is associated with a significant risk of symptomatic cardiotoxicity. Concomitant chemotherapeutic agents, received by all the affected patients, may have a contributory effect too. Cardiotoxicity seems to be completely reversible, particularly in patients without underlying cardiac disease. The patients should be informed about the symptoms and the condition recognised and managed immediately.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Eletrocardiografia/efeitos dos fármacos , Fluoruracila/efeitos adversos , Coração/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Adulto , Idoso , Cisplatino/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/toxicidade , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estudos Prospectivos
15.
Afr J Med Med Sci ; 22(1): 17-24, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7839877

RESUMO

Between 1981 and 1985, 1124 patients with histopathologically confirmed malignant disease were registered at the sole oncology clinic of Libya, 664 (59%) were males and 460 (41%) were females. Overall, malignant lymphoma (ML) was the most common cancer (180/1124, 16%), with non-Hodgkin's lymphoma (NHL) being more common (57.2%) than Hodgkin's disease (HD) (42.8%). Considered separately, lung cancer was the most common tumour (22.4%) in males with a male to female ratio among the highest in the world (18.6:1), 85% of our male patients were smokers and more than 50% had been smoking heavily for 20 years or more. Breast cancer was the most frequent tumour (29.8%) of females and the majority of our patients were of a younger age group (72.3% below 50 years). Almost all our patients were multiparous and had breast-fed their babies. Cancer of the cervix uteri was less frequent (4.5%) than ovarian cancer (7.8%). The incidence of colorectal cancer was higher (4.6%) than other African countries. Contrarily the primary tumours of liver (1.9%) and bladder (0.5%) were less frequent. Among the children, aged less than 10 years, the common solid tumours of childhood occurred in the following frequency, ML 31.2%, nervous system 19.2%, Wilm's tumour 16.8% and bone tumours 9.6%.


Assuntos
Neoplasias/epidemiologia , Vigilância da População , Adolescente , Adulto , África/epidemiologia , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Líbia/epidemiologia , Masculino , Pessoa de Meia-Idade , Oriente Médio/epidemiologia , Neoplasias/etiologia , Neoplasias/patologia , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
16.
Eur J Surg Oncol ; 17(1): 30-5, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1995354

RESUMO

Between 1977 and 1983 100 elderly women (median 76.3 years) with breast cancer were treated with tamoxifen as primary therapy. The median follow-up is 59 months. Sixty-eight responded (40 CR and 28 PR) with median response durations of 47 months and 26 months respectively. Twenty-two patients had disease stabilization for a median of 15.5 months and 10 had progressive disease. The median time to best response was 13.5 weeks for patients achieving CR and 14 weeks for those with PR. Oestrogen receptor values were obtained in 37 patients of which two patients had no ER detectable. Sixty-seven per cent of ER-unknown patients responded compared with 74% of ER-rich. Likelihood of response did not appear to depend upon T-stage or age. Survival was better than that of an unmatched historical group treated with surgery/radiotherapy and compares favourably with recent reports. Although 35% have died of breast cancer, 25% died of other causes and 22% remained free of recurrence at the time of reporting or at death. Only 11% underwent subsequent mastectomy/lumpectomy and the most frequent subsequent treatments were radiotherapy to the breast (32%) and further hormonal therapies (40%). Tamoxifen is a practical primary therapy of breast cancer in elderly and frail women obviating the need for surgery in a high proportion of cases.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Idoso Fragilizado , Tamoxifeno/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Causas de Morte , Distribuição de Qui-Quadrado , Terapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Receptores de Estrogênio/metabolismo , Indução de Remissão , Taxa de Sobrevida , Tamoxifeno/efeitos adversos , Xerostomia/induzido quimicamente
17.
Oncology ; 48(3): 226-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2023702

RESUMO

This double-blind randomized cross-over study was conducted to compare the safety and efficacy of high-dose prochlorperazine infusion and dexamethasone (HDPD) with an effective and safe combination of high-dose metoclopramide and dexamethasone (HDMD) in controlling cisplatin-induced emesis. None of the patients entering the study had received any prior chemotherapy. High-dose cisplatin was administered on an inpatient basis. Twenty eligible patients were analyzed based on the assessment made 24 h after the chemotherapy. The parameters compared were severity and duration of nausea and vomiting, severity of retching and side effects. Significantly less vomiting and retching episodes were recorded with HDPD combination. The severity of nausea was also less with this combination. There was no significant difference in the incidence of side effects.


Assuntos
Cisplatino/efeitos adversos , Metoclopramida/administração & dosagem , Proclorperazina/administração & dosagem , Vômito/tratamento farmacológico , Adulto , Dexametasona/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Vômito/induzido quimicamente
18.
Br J Cancer ; 62(5): 857-61, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2245181

RESUMO

Between 1975 and 1984, 125 cases of histologically confirmed soft tissue sarcomata (STS) were registered in the Department of Clinical Oncology in Edinburgh. Of these, 100 were eligible for analysis of prognostic factors. The overall 5-year survival rate was 21.5%. Univariate analysis demonstrated that extent of surgery, radical versus palliative or no radiotherapy, mass as a presenting symptom, metastases at presentation, site, histological type, mitotic activity, grade and UICC stage all had a statistically significant effect on survival. Analysis using the proportional hazard regression model was performed on the 87 patients for whom all variables were recorded. When all histological and clinical features and treatment modalities were included in the model then radiotherapy, surgery, necrosis, sex and mitoses were identified as independent prognostic variables. When symptoms and treatment were excluded then the multivariate analysis identified sex and mitotic activity as independent parameters. For the 33 superficial STS with tumour size recorded multivariate analysis revealed size, necrosis and cellularity as independent prognostic variables. For the 31 deep STS histological type, sex, surgery and radiotherapy were identified as independent prognostic parameters.


Assuntos
Sarcoma/mortalidade , Neoplasias de Tecidos Moles/mortalidade , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Sarcoma/patologia , Sarcoma/terapia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/terapia , Taxa de Sobrevida
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