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1.
Small ; 19(39): e2302250, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37259265

RESUMO

Cutting costs by progressively decreasing substrate thickness is a common theme in the crystalline silicon photovoltaic  industry for the last decades, since drastically thinner wafers would significantly reduce the substrate-related costs. In addition to the technological challenges concerning wafering and handling of razor-thin flexible wafers, a major bottleneck is to maintain high absorption in those thin wafers. For the latter, advanced light-trapping techniques become of paramount importance. Here we demonstrate that by applying state-of-the-art black-Si nanotexture produced by DRIE on thin uncommitted wafers, the maximum theoretical absorption (Yablonovitch's 4n2 absorption limit), that is, ideal light trapping, is reached with wafer thicknesses as low as 40, 20, and 10 µm when paired with a back reflector. Due to the achieved promising optical properties the results are implemented into an actual thin interdigitated back contacted solar cell. The proof-of-concept cell, encapsulated in glass, achieved a 16.4% efficiency with an JSC  = 35 mA cm- 2 , representing a 43% improvement in output power with respect to the reference polished cell. These results demonstrate the vast potential of black silicon nanotexture in future extremely-thin silicon photovoltaics.

2.
Phys Rev Lett ; 125(11): 117702, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32976002

RESUMO

At present, ultraviolet sensors are utilized in numerous fields ranging from various spectroscopy applications via biotechnical innovations to industrial process control. Despite this, the performance of current UV sensors is surprisingly poor. Here, we break the theoretical one-photon-one-electron barrier and demonstrate a device with a certified external quantum efficiency above 130% in UV range without external amplification. The record high performance is obtained using a nanostructured silicon photodiode with self-induced junction. We show that the high efficiency is based on effective utilization of multiple carrier generation by impact ionization taking place in the nanostructures. While the results can readily have a significant impact on the UV-sensor industry, the underlying technological concept can be applied to other semiconductor materials, thereby extending above unity response to longer wavelengths and offering new perspectives for improving efficiencies beyond the Shockley-Queisser limit.

3.
N Z Med J ; 112(1096): 357-8, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10587054

RESUMO

AIM: To determine whether there is an association between pernicious anaemia and antiphospholipid antibody syndrome. METHODS: Fifteen patients with pernicious anaemia and 11 patients with iron deficiency anaemia (controls) were evaluated for clinical parameters of thrombosis and/or the presence of antiphospholipid antibodies, antinuclear antibodies or lupus anticoagulant. RESULTS: One asymptomatic patient with pernicious anaemia had laboratory features suggestive of the antiphospholipid syndrome. An additional three patients in each group had slightly elevated antiphospholipid antibody concentrations, within one standard deviation of the normal range. CONCLUSION: The association between pernicious anaemia and antiphospholipid antibody syndrome is rare and evaluation should be guided by clinical indications.


Assuntos
Anemia Perniciosa/epidemiologia , Síndrome Antifosfolipídica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Perniciosa/imunologia , Anticorpos Antifosfolipídeos/análise , Síndrome Antifosfolipídica/imunologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Br J Rheumatol ; 33(10): 977-80, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7921762

RESUMO

The spectrum of the primary antiphospholipid syndrome has expanded in recent years. It has been associated with a number of non-thrombotic syndromes such as pulmonary hypertension, adrenal insufficiency, chorea and avascular necrosis of bone. Yet, it has not been described in association with inflammatory pulmonary disease. We describe a young male with definite primary antiphospholipid syndrome who developed insidious diffuse pulmonary infiltrates. The histopathologic examination of the involved lung demonstrated alveolitis and fibrosis. We suggest that this pulmonary involvement may represent another manifestation of the primary antiphospholipid syndrome.


Assuntos
Síndrome Antifosfolipídica/complicações , Fibrose Pulmonar/etiologia , Adulto , Anticorpos Antifosfolipídeos/análise , Síndrome Antifosfolipídica/imunologia , Humanos , Masculino , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/patologia , Radiografia
7.
Anticancer Drugs ; 5(1): 105-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8186424

RESUMO

We report a patient who developed aplastic anemia after three courses of cyclohexylchloroethylnitrousurea (CCNU), procarbazine and oncovine administered after craniotomy and irradiation for brain astrocytoma. To the best of our knowledge, aplastic anemia following CCNU has not been reported previously. The unique course of the disease and implications of this complication are discussed.


Assuntos
Anemia Aplástica/induzido quimicamente , Lomustina/efeitos adversos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Astrocitoma/terapia , Contagem de Células Sanguíneas/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/terapia , Terapia Combinada , Feminino , Humanos , Lomustina/administração & dosagem , Lomustina/uso terapêutico , Procarbazina/administração & dosagem , Vincristina/administração & dosagem
8.
Kidney Int Suppl ; 45: S161-4, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8158887

RESUMO

Ninety-four normotensive, type II diabetics with microalbuminuria and normal renal function were randomized to receive enalapril or placebo and were followed for five years. In the patients treated with enalapril, albuminuria decreased initially from 143 +/- 64 (mean +/- SD) mg/24 hours to 122 +/- 67 mg/24 hours, then a slow increase was observed to 140 +/- 134 mg/24 hours after five years. In the placebo group albuminuria increased from 123 +/- 58 mg/24 hours to 310 +/- 167 mg/24 hours after five years. The difference between the rates of change in albuminuria over time in the two groups was highly significant (P < 0.005). Kidney function, expressed as mean reciprocal creatinine, declined by 13% in the placebo group and remained stable (-1%) in the enalapril group (P < 0.05). The initial value of daily albuminuria was a good predictor of the subsequent decline in renal function (r = 0.86, P < 0.001 and r = 0.72, P < 0.001 for the enalapril and the placebo groups, respectively). Initial and subsequent mean values of cholesterol and LDL were lower in the enalapril than in the placebo group. There was a close correlation between mean cholesterol values and the decline in renal function (r = -0.58, P < 0.001). The mean blood pressure was stable in the enalapril group (initial group mean 99 +/- 2.1 mmHg, fifth year mean 100 +/- 3.2 mmHg) and increased in the placebo group from 97 +/- 3.2 mmHg to 102 +/- 3.4 mm Hg at the end of the study (P = 0.082).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Adulto , Albuminúria/urina , Pressão Sanguínea , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/urina , Feminino , Humanos , Rim/fisiopatologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
9.
J Intern Med ; 234(6): 615-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8258755

RESUMO

A 77-year-old patient developed haemorrhagic bullae on her fingers 30 months after initiation of anti-coagulation treatment with warfarin sodium for chronic atrial fibrillation and mitral insufficiency. The bullae resolved 10 days after discontinuation of the medication. Two weeks after initiation of sintrom, (3-alpha-(4-nitrophenyl)-beta-acetylethyl-4-hydroxy coumarin), the lesions recurred and resolved again upon cessation of the drug. This adverse skin reaction has not been hitherto reported.


Assuntos
Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Dermatopatias Vesiculobolhosas/induzido quimicamente , Acenocumarol/efeitos adversos , Administração Oral , Idoso , Anticoagulantes/administração & dosagem , Feminino , Humanos , Varfarina/efeitos adversos
10.
Ann Intern Med ; 118(8): 577-81, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8452322

RESUMO

OBJECTIVE: To evaluate the long-term effect of angiotensin-converting enzyme inhibition on proteinuria and on the rate of decline in kidney function in patients with type II diabetes mellitus and microalbuminuria. DESIGN: Randomized, double-blind, placebo-controlled trial. Each patient was followed for 5 years. SETTING: Six clinics for diabetes mellitus coordinated by a department of medicine in a university hospital in Israel. PATIENTS: Ninety-four normotensive, type II diabetic patients with microalbuminuria and normal renal function. INTERVENTION: The patients were randomly assigned to receive enalapril, 10 mg per day, or placebo. Any increase in blood pressure was treated with long-acting nifedipine. MEASUREMENTS: Albuminuria, blood pressure, serum creatinine, fasting blood glucose, and glycosylated hemoglobin levels, every 3 to 4 months. RESULTS: In the patients treated with enalapril, albuminuria decreased from 143 +/- 64 (mean +/- SD) mg/24 h to 122 +/- 67 mg/24 h during the first year. Thereafter, we observed a slow increase to 140 +/- 134 mg/24 h after 5 years. In the placebo group, albuminuria increased from 123 +/- 58 mg/24 h to 310 +/- 167 mg/24 h after 5 years. (Difference in rate of change in proteinuria [P < 0.05]). Kidney function (expressed as mean reciprocal creatinine) declined by 13% in the placebo group and remained stable (-1%) in the enalapril group (P < 0.05). Control of blood glucose levels remained stable, in both groups, throughout the study. The mean blood pressure was stable in the enalapril group (initial group mean, 99 +/- 2.1 mm Hg; fifth-year mean, 100 +/- 3.2 mm Hg) and increased in the placebo group from an initial mean value of 97 +/- 3.2 mm Hg to 102 +/- 3.4 mm Hg at the end of the study period (P = 0.082). CONCLUSIONS: In normotensive patients with diabetes mellitus type II, the institution of angiotensin-converting enzyme inhibition during early stages of diabetic nephropathy results in long-term stabilization of plasma creatinine levels and of the degree of urinary loss of albumin. These effects are probably independent of the antihypertensive action of these agents.


Assuntos
Albuminúria/tratamento farmacológico , Creatinina/sangue , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/tratamento farmacológico , Enalapril/uso terapêutico , Adulto , Albuminúria/etiologia , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Nifedipino/uso terapêutico , Estudos Prospectivos , Fatores de Tempo
11.
Arch Intern Med ; 152(6): 1225-9, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1599351

RESUMO

BACKGROUND: The deleterious effect of hypertension on the course of diabetic retinopathy and the protective influence of antihypertensive therapy are well known. There is, however, little information about the long-term effect of different levels of blood pressure within the normal range on the evolution of renal function in type II diabetes. METHODS: One hundred ninety-five young normotensive patients with recent-onset type II diabetes, normal renal function, and no proteinuria were followed up for 14 years. Plasma glucose, creatinine, and urinary protein levels and blood pressure were determined periodically. RESULTS: Thirty patients developed hypertension; among them, 18 developed proteinuria (0.3 g/L). Among 144 patients who remained normotensive, 30 developed proteinuria. The mean decline in renal function (decline in reciprocal creatinine [100/creatinine level], expressed as a percentage of the initial value) was 26% for normotensive patients, 43% for normotensive patients with nephropathy, 39% for hypertensive patients, and 52% for hypertensive patients with nephropathy. The degree of metabolic control was not associated with the presence of proteinuria or with the severity of renal impairment. There was a significant association between the mean blood pressure over the whole observation period and the degree of impairment in renal function. This association was significant also in the patients who remained normotensive with and without proteinuria. CONCLUSIONS: Minor elevation of blood pressure as well as values in the upper normal range may be associated with acceleration of renal damage in type II diabetes.


Assuntos
Pressão Sanguínea/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Proteinúria/fisiopatologia , Adulto , Diabetes Mellitus Tipo 2/tratamento farmacológico , Retinopatia Diabética/fisiopatologia , Feminino , Seguimentos , Humanos , Hipertensão/fisiopatologia , Masculino , Análise de Regressão
12.
Scand J Infect Dis ; 24(6): 793-6, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1287814

RESUMO

Osteomyelitis secondary to salmonella infection is well documented in the literature. Infection in more than one focus has also been described. To the best of our knowledge this is the first report of recurrent osteomyelitis in a normal host (a 35-year-old man) with the same organism (S. paratyphi C) in different sites 17 years apart.


Assuntos
Osteomielite/microbiologia , Febre Paratifoide/microbiologia , Salmonella paratyphi C/isolamento & purificação , Adulto , Humanos , Masculino , Osteomielite/diagnóstico , Febre Paratifoide/diagnóstico , Tíbia/microbiologia , Fatores de Tempo
14.
J Rheumatol ; 18(3): 464-7, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1856817

RESUMO

We describe a patient with Sezary syndrome and seronegative symmetric polyarthritis. Detailed analysis of the synovial membrane, including T lymphocyte subset delineation, demonstrated that malignant synovial infiltration was the direct cause of arthritis in this patient.


Assuntos
Periartrite/etiologia , Síndrome de Sézary/complicações , Idoso , Artrite Reumatoide/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Linfoma de Células T/patologia , Periartrite/diagnóstico , Síndrome de Sézary/patologia , Membrana Sinovial/patologia , Subpopulações de Linfócitos T/patologia
15.
Urology ; 33(4): 317-9, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2929066

RESUMO

A hygroma of the left kidney was found at surgery in a thirty-five-year-old woman, who presented with anemia, hypertension, and a left abdominal mass. There was a very high sedimentation rate and fine needle aspiration yielded bizarre cells which raised the possibility of malignancy. Compression of the kidney by the cystic structure probably interfered with renal blood flow and was responsible for the elevated blood pressure which receded to normal after removal of the cyst and the left kidney.


Assuntos
Hipertensão Renal/etiologia , Nefropatias/complicações , Linfangioma/complicações , Adulto , Feminino , Humanos , Nefropatias/diagnóstico , Nefropatias/patologia , Nefropatias/cirurgia , Linfangioma/diagnóstico , Linfangioma/patologia , Linfangioma/cirurgia
17.
Am Heart J ; 113(5): 1078-84, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3577999

RESUMO

Ten patients with an array of moderate to severe adverse effects resulting from digitalis were effectively treated by hemoperfusion through small columns which contained antidigoxin antibodies bound to polyacrolein microspheres in agarose macrospheres (APAMB). The procedure was well tolerated. There was no detectable damage to formed blood elements and no changes in electrolytes, liver enzymes, or other related biochemical parameters. Despite some theoretic considerations to the contrary, the removal of a relatively small load of digoxin resulted in amelioration of the clinical symptoms and ECG abnormalities associated with digitalis. No rebound phenomena of intoxication or posthemoperfusion increase in digoxin serum levels were noted over the subsequent 5 to 6 days. A further increase in the capacity of the columns may render this method a safe and convenient emergency procedure for patients with digitalis toxicity.


Assuntos
Anticorpos , Digoxina/intoxicação , Cardiopatias/tratamento farmacológico , Hemoperfusão/métodos , Acroleína , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Digoxina/sangue , Digoxina/imunologia , Feminino , Humanos , Masculino , Microesferas , Pessoa de Meia-Idade , Polímeros , Sefarose
18.
Artigo em Inglês | MEDLINE | ID: mdl-3440130

RESUMO

Extracorporeal hemoperfusion through polyacrolein microsphere beads (APAMB) attached to antidigoxin antibodies is an effective treatment of digitalis intoxication. In order to increase the binding capacity of the APAMB columns the active sites of the antidigoxin antibodies were protected by ouabain during the binding to the microbeads. This brought about an 11-18 percent increase in digoxin binding capacity of the columns. It was also found that binding capacity does not increase with the rise of antibody concentration beyond a certain limit. Protection of antibody binding sites and determination of optimal concentration are, therefore necessary steps during preparation of antibody based hemoperfusion columns.


Assuntos
Glicosídeos Digitálicos/intoxicação , Digoxina/imunologia , Hemoperfusão , Ouabaína , Acroleína , Humanos , Microesferas , Polímeros
19.
Clin Nephrol ; 25(4): 199-201, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3516483

RESUMO

Bilateral fibromuscular dysplasia of the renal arteries was the underlying pathology in a 51-year-old woman with severe hypokalemia and borderline hypertension. Very high renin levels were found in both renal veins. The secondary hyperaldosteronism was most probably responsible for the persistant hypokalemia in this patient.


Assuntos
Arteriopatias Oclusivas/complicações , Displasia Fibromuscular/complicações , Hipopotassemia/etiologia , Artéria Renal/patologia , Feminino , Displasia Fibromuscular/patologia , Humanos , Hiperaldosteronismo/etiologia , Pessoa de Meia-Idade , Renina/sangue
20.
Am Heart J ; 110(1 Pt 1): 30-9, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4013987

RESUMO

The usefulness of a new biocompatible, specific immunosorbent, Agarose-Polyacrolein Microsphere Beads--Antidigoxin antibodies (APAMB-AD) for hemoperfusive removal of digoxin in digoxin intoxicated dogs is described. The sorbent contains antidigoxin antibodies covalently bound to polyacrolein microspheres, 0.2 micron in diameter. Thousands of microspheres are matrix-encapsulated in cross-linked agarose to form beads 500 to 800 micron in diameter. The sorbent removes digoxin specifically, leaving other components of the blood intact, in contrast to the nonspecific sorbents (charcoal and ion exchange resins) currently in use. Digoxin-intoxicated dogs looked ill, vomited, and their ECGs showed malignant arrhythmias which were reversed during the first hour of hemoperfusion. By 2 hours of hemoperfusion, the ECG tracings returned to the preintoxication state. Up to 27% of the total body digoxin burden was removed. The sorbent is biocompatible. Neither the formed elements nor a battery of the routinely assayed soluble components of the blood or complement (C'4) were altered significantly during the hemoperfusion trials. The dogs tolerated the hemoperfusion well and all survived the intoxication. Nonhemoperfused dogs or dogs whose blood was hemoperfused through beads lacking antidigoxin did not survive the digoxin intoxication.


Assuntos
Anticorpos , Digoxina/intoxicação , Hemoperfusão , Intoxicação/terapia , Acroleína/uso terapêutico , Animais , Digoxina/imunologia , Cães , Microesferas , Polímeros/uso terapêutico , Sefarose
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