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1.
Phys Rev Lett ; 131(18): 186704, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977632

RESUMO

EuCd_{2}As_{2} is now widely accepted as a topological semimetal in which a Weyl phase is induced by an external magnetic field. We challenge this view through firm experimental evidence using a combination of electronic transport, optical spectroscopy, and excited-state photoemission spectroscopy. We show that the EuCd_{2}As_{2} is in fact a semiconductor with a gap of 0.77 eV. We show that the externally applied magnetic field has a profound impact on the electronic band structure of this system. This is manifested by a huge decrease of the observed band gap, as large as 125 meV at 2 T, and, consequently, by a giant redshift of the interband absorption edge. However, the semiconductor nature of the material remains preserved. EuCd_{2}As_{2} is therefore a magnetic semiconductor rather than a Dirac or Weyl semimetal, as suggested by ab initio computations carried out within the local spin-density approximation.

2.
Artigo em Inglês | MEDLINE | ID: mdl-25375505

RESUMO

Subflorescence refers to crystallized salt structures that form inside a porous medium. We report a drying experiment revealing major development of subflorescence in the dry region of the porous medium away from the liquid zone. Using a combination of image analyses and numerical computations, we show that the growth is directly correlated to the evaporation flux distribution along the boundary of the growing salt structure. This indicates that the salt is transported into the domain occupied by the salt structure in the porous medium up to the structure periphery, where salt deposition takes place. This is confirmed when a growing salt structure encounters dry subflorescence formed earlier during the drying process. The dry subflorescence is reimbibed and resumes its growth. The analysis also suggests that the solution within the growing subflorescence is in equilibrium with the crystallized salt wall. These results shed light on the growth mechanisms of subflorescence, a phenomenon that can play a fundamental role in several important issues such as carbon dioxide sequestration or salt weathering.


Assuntos
Cristalização , Porosidade , Sais , Simulação por Computador , Análise de Elementos Finitos , Processamento de Imagem Assistida por Computador , Modelos Químicos
3.
Food Addit Contam ; 16(7): 307-12, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10656056

RESUMO

Milk samples were collected from 32 nursing mothers living in the Beirut area, Lebanon. Dietary intakes of participating mothers were obtained from data of their diet histories, 24 h dietary recalls and food frequency questionnaires. Milk samples were screened for the presence of organochlorine pesticide residues and DDE levels were estimated using gas chromatographic techniques. The relationship between consumption of various food groups and DDE content of milk was investigated. A positive correlation was found between the consumption of either/or high fat meat, tuna fish and DDE levels in milk. Consumption of poultry products showed a weak correlation with DDE content of milk, whereas consumption of vegetable oils showed a negative correlation.


Assuntos
Diclorodifenil Dicloroetileno/análise , Dieta , Inseticidas/análise , Leite Humano/química , Resíduos de Praguicidas/análise , Adolescente , Adulto , Animais , Cromatografia Gasosa , Feminino , Humanos , Lactação/fisiologia , Carne , Óleos de Plantas , Atum
4.
Isr J Med Sci ; 31(2-3): 169-71, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7744588

RESUMO

In the Multiple Primary Tumor Registry of the Northern Israel Cancer Center we found 247 patients with breast cancer who developed a second primary tumor. The major sites of the second tumor were mainly the other breast (42%), colon (14%), ovary (8%), and endometrium (7%). Only 24% of the second tumors were diagnosed in asymptomatic patients on a routine follow-up examination; 60% of these patients had contralateral breast cancer and 8% had colon cancer. More patients in this group had localized disease as compared to those diagnosed following appearance of symptoms. The time interval between the first symptoms suggesting malignancy and the diagnosis was longer than 6 weeks in 7%, as compared to 24% in patients diagnosed with a single cancer. In 69 patients (30%), delay was found between the first medical consultation and diagnosis. The agents responsible for the delay were the specialist (32%), the system and normal tests (54%), and the patients (8%). In the diagnosis of a single tumor, the physician and the patient shared a similar percentage of responsibility (29% and 33%). Educational efforts aimed mainly at physicians and patients regarding the early detection of second primary tumors are advocated. Methods that have been proven to detect cancer early, such as mammography, stool for occult blood, and sigmoidoscopy, should be utilized in asymptomatic patients with single tumors in the same way as in the healthy population.


Assuntos
Neoplasias da Mama , Segunda Neoplasia Primária/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
5.
Eur J Gynaecol Oncol ; 16(3): 195-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7664766

RESUMO

The clinical characteristics of patients with second primary tumors in the ovary and endometrium were compared to those with single primary tumors treated at our Center during the same period of time. Despite the fact that the patients were under medical surveillance for the first primary tumor, most second tumors were diagnosed following patient symptoms and complaints, and not at a routine follow-up appointment. Patients with a second primary endometrial cancer had a more advanced stage of disease at diagnosis as compared to those with single endometrial cancer. This was not found to be true for patients with second ovarian cancer. Patients with primary breast cancer and colon cancer, lymphoma or melanoma were found to be at higher risk for developing a second primary tumor in the endometrium or ovary as compared to those with a primary tumor at other sites. Although there are no proven means for the early detection of these gynecologic malignancies, it seems prudent to draw the attention of medical practitioners to the need for a better gynecologic evaluation for women with cancer at other sites during their follow-up visits. Studies on the efficacy of currently available diagnostic techniques should be carried out to evaluate their yield in this high risk group.


Assuntos
Neoplasias do Endométrio/diagnóstico , Segunda Neoplasia Primária , Neoplasias Ovarianas/diagnóstico , Neoplasias da Mama , Neoplasias do Colo , Neoplasias do Endométrio/patologia , Feminino , Humanos , Neoplasias Renais , Melanoma , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias da Bexiga Urinária
6.
Dis Colon Rectum ; 35(5): 457-61, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1568396

RESUMO

The clinical characteristics of 152 patients diagnosed with two primary metachronous tumors--one or both of them in the colon--were studied. Nineteen patients had both primary tumors in the colon (Group I), 59 had the first primary tumor in the colon and the second tumor elsewhere (Group II), and 74 had the second primary tumor in the colon and the first primary tumor elsewhere (Group III). The group in which the second primary tumor was in the colon included significantly more female patients than did the other two groups, with a younger median age at diagnosis of first tumor. The median time interval between the two primary tumors was 44, 57, and 62 months in Groups I, II, and III, respectively. The number of clinic visits during the year before diagnosis of the second primary was similar in all groups, but only 60 percent of the patients kept their follow-up appointment. In most instances, the diagnosis was made after the patients' symptoms, although only a small percentage of the second primary tumors (15-30 percent) were diagnosed during routine follow-up. The second primary tumor occurred in the field of radiotherapy of the first primary tumor in 27 of 35 patients who received radiotherapy. To increase the number of patients diagnosed in an earlier stage of disease, they should be urged to keep their follow-up appointment, and physicians following patients with single tumors should be aware of the increased likelihood of a second tumor. To increase the cure rate of those tumors, efforts toward early diagnosis are warranted. This includes physical examination and mammography to detect breast cancer in women, annual occult blood tests and rectal examination, and sigmoidoscopy or colonoscopy at three-year intervals to detect colon cancer early.


Assuntos
Neoplasias do Colo , Segunda Neoplasia Primária , Idoso , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/diagnóstico , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
7.
Clin Ther ; 11(4): 539-44, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2776168

RESUMO

Patients with osteoarthritis make up the largest group of users of nonsteroidal anti-inflammatory drugs (NSAIDs), but the effects of these agents on the gastrointestinal mucosa of such patients have not been well studied. This article describes a short-term comparison of two widely used NSAIDs, diflunisal and ibuprofen, in patients requiring these medications for their osteoarthritis. Efficacy, tolerability, and endoscopically documented effects of these drugs on the gastric and duodenal mucosa were assessed. Consenting, eligible patients were randomly assigned to one of the two study drugs for a two-week course. Clinical assessments were made after each week of treatment. Fiberoptic endoscopy and laboratory tests were performed before and after the treatment period. Thirty patients completed the study: 16 received diflunisal and 14 received ibuprofen. Similar improvements in pain, joint mobility, functional capacity, and joint swelling and tenderness were observed in both treatment groups. Transient, mild abdominal cramping was reported by two patients in each group; one patient receiving ibuprofen complained of transient dizziness. No patient withdrew from the study because of side effects. Follow-up endoscopy revealed slight (grade 1) changes in the gastric mucosa of two patients in each treatment group. An additional patient in the ibuprofen group had gastric erosions (grade 2) at the end of the study. Endoscopic changes were not correlated with symptoms. Diflunisal and ibuprofen were found to be similarly effective and well tolerated in the treatment of osteoarthritis. Their use may be associated with some gastrointestinal side effects even during short-term use.


Assuntos
Diflunisal/efeitos adversos , Mucosa Gástrica/efeitos dos fármacos , Ibuprofeno/efeitos adversos , Mucosa Intestinal/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Salicilatos/efeitos adversos , Idoso , Diflunisal/uso terapêutico , Duodeno/efeitos dos fármacos , Feminino , Humanos , Ibuprofeno/uso terapêutico , Masculino , Pessoa de Meia-Idade
8.
Dig Dis Sci ; 34(1): 118-22, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910668

RESUMO

A case of idiopathic central serous chorioretinopathy with bullous retinal detachment occurring in a patient with Crohn's disease is described. This rare eye condition (36 reported cases in the world's literature) has previously been seen in association with ulcerative colitis, and its occurrence in a patient with Crohn's disease suggests that it may represent another ophthalmologic complication of inflammatory bowel disease.


Assuntos
Corioide , Doença de Crohn/complicações , Descolamento Retiniano/etiologia , Adulto , Angiofluoresceinografia , Humanos , Masculino , Doenças da Úvea/etiologia
9.
J Clin Gastroenterol ; 9(5): 514-7, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3680899

RESUMO

We evaluated the significance of bile seen in the stomach at the time of endoscopy. Twenty-three percent of 110 consecutive patients undergoing elective panendoscopy were found to have bile in their stomachs. Gastric biopsies were obtained from these patients. To assess the significance of bile reflux, the patients underwent a quantitative gastric bile analysis on two separate days. On day 1, gastric juice was aspirated by nasogastric suction, and bile acid concentrations were measured. On day 2, bile reflux into the stomach was quantitated by scintiscan measurement of gastric nucleotide after intravenous administration of 99mTc-DISIDA. Approximately half the patients with bile reflux showed histologic evidence of mucosal injury. However, fewer than half with histologic injury had significant bile reflux when measured by quantitative methods. There was no correlation among the gastric bile acid concentration, degree of histologic injury, or severity of endoscopic changes. We conclude that finding bile reflux at endoscopy is probably of no clinical significance.


Assuntos
Refluxo Biliar/patologia , Doenças Biliares/patologia , Mucosa Gástrica/patologia , Gastroscopia , Refluxo Biliar/diagnóstico por imagem , Humanos , Iminoácidos , Compostos Organometálicos , Cintilografia , Disofenina Tecnécio Tc 99m
10.
Am J Gastroenterol ; 82(7): 625-31, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3605023

RESUMO

Esophageal function was prospectively studied in 50 consecutive insulin-requiring diabetes mellitus patients. The patients were stratified in three groups: A) 18 without peripheral neuropathy (PN); B) 20 with PN but no autonomic neuropathy; C) 12 with PN and autonomic neuropathy. Twelve patients (four B, eight C) had gastrointestinal symptoms including six with dysphagia. Radionuclide esophageal emptying was abnormal in 55, 70, and 83% of patients in groups A, B, and C, respectively. Eleven of the 12 (92%) symptomatic and 23 of the 38 (60%) asymptomatic diabetes mellitus patients had abnormal emptying. Five of six patients with dysphagia had abnormal emptying. Esophageal manometry was also performed in 15 patients. Twelve patients had abnormal manometry. These included nutcracker esophagus in two, achalasia in one, and increased percentage of multipeaked and simultaneous contractions in nine. There were no significant correlations between radionuclide esophageal emptying, manometric changes and symptoms. Gastrointestinal symptoms were more common in the presence of autonomic neuropathy. Delayed esophageal emptying was more profound in the presence of PN, but abnormal esophageal emptying was present in patients with neuropathy as commonly as patients without. Furthermore, the presence of diabetic retinopathy, duration or control of diabetics, and fasting blood sugar did not influence the frequency of abnormal esophageal emptying. Our data indicate that esophageal dysfunction is common in male diabetics even in the absence of clinical PN and retinopathy, suggesting that diabetic gastroenteropathy can occur in the absence of significant diabetic complications. Commonly observed abnormal esophageal manometry in diabetics is not necessarily accompanied by significant functional disturbances or symptoms.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico por imagem , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Esôfago/diagnóstico por imagem , Doenças do Sistema Nervoso Autônomo/diagnóstico por imagem , Transtornos de Deglutição/diagnóstico por imagem , Neuropatias Diabéticas/diagnóstico por imagem , Esôfago/fisiopatologia , Humanos , Masculino , Manometria , Peristaltismo , Cintilografia , Coloide de Enxofre Marcado com Tecnécio Tc 99m
11.
Am J Gastroenterol ; 82(6): 523-5, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3578232

RESUMO

A strong gag reflex may be a limiting factor to perform esophageal motility in some patients. Even though local anesthetics could alleviate such a problem, they are not used for fear of interfering with various manometric parameters. In this study, we evaluated the effect of topical pharyngeal local anesthesia on lower esophageal sphincter pressure, amplitude, duration, and velocity of esophageal contractions. We also studied its effects on the patient's tolerance. Esophageal motility was performed before and after topical anesthesia with 20% benzocaine. The baseline tracing and the tracing obtained after topical anesthesia were number coded and separated. They were evaluated blindly as to the pressure in the lower esophageal sphincter, amplitude, duration, and velocity of esophageal contractions. An average of 10 wet swallows was used to determine the above values. There was no significant change in the lower esophageal sphincter pressure or the amplitude of esophageal contractions after benzocaine. Similarly, there was no change in the duration or velocity of peristaltic activity. The patient's tolerance to the tube was unchanged or improved in 12 of 14 patients. Six patients had some difficulty in swallowing, but were able to compensate by sucking on the syringe. Our results indicate that topical pharyngeal anesthesia does not affect the usually measured manometric parameters; and while it may improve the patient's tolerance to the manometric catheter, it interferes with the ability to swallow.


Assuntos
Anestésicos Locais/farmacologia , Esôfago/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Adulto , Benzocaína/farmacologia , Esôfago/fisiologia , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Contração Muscular/efeitos dos fármacos , Pressão
12.
Am J Gastroenterol ; 82(5): 406-9, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3578220

RESUMO

The effect of hypertonic glucose as a provocative test was studied in 51 patients with noncardiac chest pain, 15 patients with esophagitis, and 16 asymptomatic controls. It was compared to esophageal perfusion with 0.1 N HCl and saline and intravenous administration of 10 mg edrophonium. Continuous esophageal manometric recordings were performed at the time of testing. The patients' symptoms were monitored every minute. The effect of these solutions and edrophonium on lower esophageal sphincter (LES) pressure and amplitude of esophageal contractions was also evaluated. Esophageal perfusion with hypertonic glucose, saline, or acid had no significant effect on LES pressure or amplitude of esophageal contractions in most patients. Edrophonium, however, resulted in a significant rise in the amplitude of esophageal contractions and the LES pressure in all groups studied. Hypertonic glucose resulted in chest pain in 13.6% of patients with noncardiac chest pain and 20% of those with esophagitis, whereas edrophonium reproduced the pain in 38.7 and 37%, respectively. Our results indicate that hypertonic glucose is not effective as a provocative test for noncardiac chest pain nor does it contribute to the chest pain in esophagitis. They also had no significant effect on the amplitude of esophageal contractions or LES pressure. Edrophonium continues to be a relatively sensitive test for noncardiac chest pain.


Assuntos
Dor no Peito/diagnóstico , Doenças do Esôfago/diagnóstico , Esôfago/fisiopatologia , Glucose , Adolescente , Adulto , Idoso , Transtornos de Deglutição/diagnóstico , Diagnóstico Diferencial , Edrofônio , Acalasia Esofágica/diagnóstico , Humanos , Ácido Clorídrico , Soluções Hipertônicas , Manometria , Pessoa de Meia-Idade , Peristaltismo/efeitos dos fármacos
15.
Am J Gastroenterol ; 80(7): 526-8, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4014101

RESUMO

A case of achalasia associated with squamous cell carcinoma of the esophagus is presented. Microscopic examination of the resected esophagus demonstrated abundant nerve fibers but absent ganglion cells throughout the tumor-involved segment. This finding is believed to be the cause of achalasia in this patient.


Assuntos
Carcinoma de Células Escamosas/complicações , Acalasia Esofágica/etiologia , Neoplasias Esofágicas/complicações , Acalasia Esofágica/patologia , Esôfago/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Plexo Mientérico/patologia , Degeneração Neural
17.
South Med J ; 78(3): 312-5, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3975747

RESUMO

The effect of nifedipine on esophageal symptoms was evaluated in 20 patients with primary esophageal motor disorders. The patients were randomized to receive nifedipine (10 mg t.i.d.) or placebo for two weeks, and then crossed over to receive the other medication. Ten patients had hypertensive lower esophageal sphincter, four had diffuse esophageal spasm, three had vigorous achalasia, two had "nutcracker esophagus," and one patient had achalasia. The score of chest pain or dysphagia was recorded on a scale of 0 to 10 during each study. The patients who received nifedipine improved significantly compared to those who received placebo. This improvement was most marked in patients with hypertensive lower esophageal sphincter. No significant side effects or changes in blood pressure were encountered in any of the study groups. Our results indicate that patients with primary esophageal motor disorders have a good clinical response to nifedipine therapy.


Assuntos
Doenças do Esôfago/tratamento farmacológico , Nifedipino/uso terapêutico , Adulto , Idoso , Acalasia Esofágica/tratamento farmacológico , Junção Esofagogástrica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nifedipino/administração & dosagem , Placebos , Espasmo/tratamento farmacológico
20.
Surgery ; 95(6): 640-3, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6729700

RESUMO

This study was undertaken to determine whether fat absorption is improved following longitudinal pancreaticojejunostomy. Ten consecutive patients with chronic pancreatitis underwent measurement of fat absorption (fecal fat, 14C-labeled phenylacetic dipalmitate oil absorption test) before and after operation. Fecal fat increased in 8 of 10 patients following side-to-side pancreaticojejunostomy. However, the average postoperative fecal fat increase of 4.3 gm was of no clinical significance. The observed mild postoperative decline in fat absorption was confirmed by the 14C-labeled phenylacetic dipalmitate test. An improvement in postoperative fat absorption following side-to-side pancreaticojejunostomy Roux-en-Y should not be expected. The primary indication for this procedure for patients with chronic pancreatitis continues to be intractable pain.


Assuntos
Gorduras na Dieta/metabolismo , Jejuno/cirurgia , Pâncreas/cirurgia , Pancreatite/cirurgia , Adulto , Doença Crônica , Fezes/análise , Feminino , Humanos , Lipídeos/análise , Masculino , Dor Intratável/terapia , Ductos Pancreáticos/cirurgia , Pancreatite/metabolismo , Fenilacetatos , Fatores de Tempo
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