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1.
Phys Rev Lett ; 115(19): 195303, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26588394

RESUMO

We propose a realistic scheme to detect the 4D quantum Hall effect using ultracold atoms. Based on contemporary technology, motion along a synthetic fourth dimension can be accomplished through controlled transitions between internal states of atoms arranged in a 3D optical lattice. From a semiclassical analysis, we identify the linear and nonlinear quantized current responses of our 4D model, relating these to the topology of the Bloch bands. We then propose experimental protocols, based on current or center-of-mass-drift measurements, to extract the topological second Chern number. Our proposal sets the stage for the exploration of novel topological phases in higher dimensions.

2.
J Urol ; 153(6): 1966-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7752372

RESUMO

Retroperitoneal pediatric laparoscopic nephrectomy is described in 3 patients requiring 3 to 5 hours with an estimated blood loss of 10 to 60 cc. The children returned to school within 7 days postoperatively. Advantages of this procedure include the avoidance of intraoperative repositioning of the patient and easy conversion to an open lumbodorsal approach, if necessary; early laparoscopic visualization of the renal artery; applicability in cases of previous abdominal surgery, and avoidance of intraperitoneal adhesion.


Assuntos
Laparoscopia/métodos , Nefrectomia/métodos , Adolescente , Criança , Feminino , Humanos , Masculino , Espaço Retroperitoneal
3.
Reg Anesth ; 18(5): 318-21, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7903550

RESUMO

BACKGROUND AND OBJECTIVES: alpha-adrenergic antagonists can be effective in the treatment of sympathetically maintained pain. METHODS: Oral terazosin was prescribed to treat sympathetically maintained pain refractory to other therapies. RESULTS: The authors describe a patient whose symptoms could not be controlled with commonly prescribed therapies, who obtained total relief of sympathetically maintained pain and vasospasm with terazosin, a new alpha 1 antagonist. CONCLUSIONS: Terazosin is effective in the treatment of sympathetically maintained pain when given once daily because of a long elimination half-time and a long duration of action. This may encourage better patient compliance than do other alpha antagonists of shorter effective duration.


Assuntos
Antagonistas Adrenérgicos alfa/uso terapêutico , Dor/tratamento farmacológico , Dor/fisiopatologia , Prazosina/análogos & derivados , Sistema Nervoso Simpático/fisiopatologia , Adulto , Feminino , Humanos , Prazosina/uso terapêutico
4.
Arch Biochem Biophys ; 297(2): 285-90, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1497348

RESUMO

The amino acid sequence of the fatty acid binding protein (FABP) from flight muscle of the locust, Schistocerca gregaria, has been determined. The sequence of the N-terminal 39 amino acid residues, determined by automated Edman degradation, was used to prepare a degenerate oligonucleotide that corresponded to amino acid residues 16-23. cDNA coding for FABP was constructed from flight muscle mRNA and amplified by the polymerase chain reaction using the degenerate oligonucleotide and an oligo dT-NotI primer adapter as primers. The amplification product was cloned and sequenced. Additionally, a cDNA library of flight muscle mRNA was prepared and screened with a 414-bp probe prepared from the clone. The primary structure of locust FABP was compared with the proteins in the Swiss protein databank and found to have significant homology with mammalian FABPs over the entire 133-residue sequence. The best match was versus human heart FABP (41% identity), attesting to the highly conserved nature of this protein. The results suggest that locust muscle FABP is a member of the lipid binding protein superfamily and may provide valuable insight into the evolution of this abundant protein class.


Assuntos
Proteínas de Transporte/genética , Músculos/metabolismo , Proteínas de Neoplasias , Proteínas Supressoras de Tumor , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , DNA/genética , Bases de Dados Factuais , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Ácidos Graxos/metabolismo , Voo Animal , Biblioteca Gênica , Gafanhotos , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , Homologia de Sequência do Ácido Nucleico
5.
J Clin Gastroenterol ; 13(2): 195-7, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2033227

RESUMO

We describe a previously unreported association between somatostatinoma and congenital pseudoarthrosis. Because pseudoarthrosis is part of von Recklinghausen's disease, in turn with an association with somatostatinoma, we speculate on a link between pseudoarthrosis and somatostatinoma.


Assuntos
Neoplasias Duodenais/complicações , Pseudoartrose/congênito , Somatostatinoma/complicações , Neoplasias Duodenais/patologia , Duodeno/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Somatostatinoma/patologia
6.
Radiother Oncol ; 19(2): 145-57, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2123987

RESUMO

In 50 patients receiving radical radiotherapy for carcinoma of the bladder a well-defined tumour was observed in the bladder either by trans-abdominal ultrasonography or by CT scanning prior to treatment. The histological type was transitional cell carcinoma 46, adenocarcinoma 1 and squamous cell carcinoma 3. The cross-sectional area of the tumour in the transverse plane was measured before the start of radiotherapy. In 37 patients serial measurements were made by ultrasonography during and after radical radiotherapy. In three patients no regression was seen during the first 14-27 days of treatment. In 34 patients with transitional cell carcinoma the median area-halving time was 37 days. Serial measurements of the volume of the tumour before, during and after radiotherapy were made by CT scanning in 29 patients. In two patients the tumour progressed with a volume-doubling time of 93 and 108 days, respectively. In 25 patients with transitional cell carcinoma the median volume-halving time was 29 days with a median area-halving time of 44 days. Linear-regression analysis of the initial tumour areas (31 patients) as measured by ultrasonography and CT scanning was performed. The correlation coefficient was r = 0.69. The correlation coefficient for the area halving-times measured both by ultrasonography and CT scanning was r = 0.53 (nine patients). Biphasic regression with a second slower phase with area-halving and volume-halving times of several hundred days was observed in six patients. Calcification of the tumour during and after radiotherapy was observed in several patients. No significant change in the CT number of the tumour was observed after radiotherapy. The median initial tumour volume as measured by CT scanning was 38 (7-211) cm3. The median initial tumour area as measured by ultrasonography was 16 (6-40) cm2. A tumour of median size with a median halving-time would take 120 days (4 months) to regress completely. Cystoscopy within 6 months of the start of radiotherapy is unlikely to be of value because many bladder tumours are continuing to regress during this period of time. Progression of the tumour during or after radiotherapy can be detected either by CT scanning or ultrasonography.


Assuntos
Carcinoma de Células de Transição/radioterapia , Radioterapia de Alta Energia/métodos , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Carcinoma de Células de Transição/diagnóstico por imagem , Feminino , Humanos , Masculino , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X , Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico por imagem
7.
J Biol Chem ; 265(18): 10551-5, 1990 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-2355011

RESUMO

Insect plasma lipid transfer particle (LTP) catalyzes vectorial net transfer of diacylglycerol (DAG) from Manduca sexta larval high density lipophorin (HDLp-L) to human low density lipoprotein (LDL) producing an LDL of lower density and lipophorin subspecies of higher density. At equilibrium, a stable DAG-depleted very high density lipophorin species (density = 1.25 g/ml) is formed. Electrophoretic analysis of the substrate and product lipoproteins showed that apoprotein exchange or transfer between human LDL and lipophorin did not occur during the lipid transfer reaction. Facilitated net transfer of cholesteryl ester, free cholesterol, and phospholipid occurred to a much lower extent than DAG net transfer, indicating that under these conditions, LDL serves as a sink for lipophorin-associated DAG. This reaction, therefore, provides a method whereby the mass of lipid associated with human LDL can be modified in vitro without alteration of its apoprotein component. The DAG content of LDL increased in a linear manner with respect to LTP concentration and time during the initial phase of the reaction, demonstrating the utility of this system as a quantitative assay method for LTP-mediated net DAG transfer. When [3H]DAG-labeled LDL was prepared and employed in transfer experiments with unlabeled lipophorin, labeled DAG was recovered in the HDLp-L fraction. The amount of labeled DAG recovered in the HDLp-L fraction was dependent on the ratio of LDL to HDLp-L in the reaction. Thus, in this system, LTP-mediated DAG redistribution is bidirectional, suggesting that the final equilibrium distribution of lipid may be dictated by the properties of potential donor/acceptor lipoproteins rather than by an inherent particle substrate specificity of LTP.


Assuntos
Proteínas de Transporte/metabolismo , Diglicerídeos/metabolismo , Glicerídeos/metabolismo , Lepidópteros/metabolismo , Lipoproteínas LDL/metabolismo , Mariposas/metabolismo , Animais , Eletroforese em Gel de Poliacrilamida , Hemolinfa/metabolismo , Humanos , Larva , Lipoproteínas/isolamento & purificação , Peso Molecular , Ligação Proteica
8.
J Urol ; 141(5): 1091-4; discussion 1093-4, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2785219

RESUMO

Cystoprostatectomy specimens were evaluated in 66 male patients operated on for a pathological condition of the bladder with no evidence of prostatic malignancy on preoperative clinical assessment. There were 38 prostate cancers identified in 25 of 66 patients (38 per cent). Multiple foci of adenocarcinoma were noted in 10 of 25 patients (40 per cent). The mean tumor volume was 0.11 cc, with half of the cancers being less than or equal to 0.01 cc in volume. All 38 cancers were completely localized to the prostate and exact anatomical sites of origin for each of the cancers within the prostate were mapped. Whereas anatomical distribution of the cancers in the anteroposterior dimension was roughly uniform, a distinct predominance of apical prostatic cancers was observed. Possible anatomical explanations and implications of these findings in terms of the apical surgical margins at radical prostatectomy and cystoprostatectomy, and the new technologies currently available for diagnosis of prostate cancer are discussed.


Assuntos
Adenocarcinoma/patologia , Próstata/patologia , Neoplasias da Próstata/patologia , Neoplasias da Bexiga Urinária/cirurgia , Adenocarcinoma/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia , Neoplasias da Próstata/epidemiologia , Bexiga Urinária/cirurgia
9.
J Reprod Med ; 33(4): 387-90, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3130483

RESUMO

Ovarian hyperstimulation syndrome (OHS) is one of the potential complications associated with the use of human menopausal gonadotropin therapy. We recently dealt with a case of severe OHS presenting features of liver dysfunction; such a case has not been reported on before.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Infertilidade Feminina/tratamento farmacológico , Menotropinas/efeitos adversos , Indução da Ovulação/efeitos adversos , Adulto , Citoplasma/ultraestrutura , Feminino , Humanos , Hepatopatias/patologia , Mitocôndrias Hepáticas/ultraestrutura , Ovário/efeitos dos fármacos
10.
Ann Emerg Med ; 17(1): 25-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3337410

RESUMO

Axial (in-line) traction is recommended as a stabilizing maneuver during orotracheal intubation of a trauma victim with a potential cervical spine injury. There are no published data demonstrating the safety of this technique in trauma patients with an unstable cervical spine. In our study, 17 victims of blunt traumatic arrest had radiographic analysis of the cervical spine during orotracheal intubation, with and without axial traction. Four (24%) had unstable injuries, which included a C6-7 fracture dislocation, a Hangman's fracture, and two atlanto-occipital dislocations. Axial traction during oral intubation in these victims resulted in a mean distraction at the fracture site of 7.75 mm. Axial traction produced 4 mm of posterior subluxation in the C6-7 fracture dislocation, demonstrating that axial traction alone may result in subluxation, as well as distraction. This depends on the direction of the traction force and integrity of surrounding tissues. We recommend that trauma patients requiring intubation prior to a complete examination and radiographic analysis of the cervical spine be nasotracheally intubated without axial traction, and that the head and neck be stabilized in the neutral position. If a contraindication to nasotracheal intubation exists, a cricothyroidotomy should be performed.


Assuntos
Emergências , Intubação Intratraqueal , Traumatismo Múltiplo/terapia , Traumatismos da Coluna Vertebral/terapia , Tração , Estudos de Avaliação como Assunto , Fraturas Ósseas/diagnóstico por imagem , Humanos , Radiografia , Traumatismos da Coluna Vertebral/diagnóstico por imagem
11.
J Urol ; 139(1): 61-5, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3336108

RESUMO

Morphological features in radical prostatectomy specimens from 11 stage A and 73 stage B prostatic carcinomas were compared by mapping of tumor locations, and determinations of cancer volumes and histological patterns. Small stage A cancers were located anteromedially, while small stage B carcinomas were concentrated against the posterior capsule at the rectal surface. Small stage A carcinomas commonly invaded the anterior fibromuscular stroma and benign prostatic hyperplasia nodules, features that were uncommon even in large stage B tumors. Stage A cancers often appeared to arise within benign prostatic hyperplasia nodules and had a distinctive histological appearance. Even when large, stage A carcinomas tended not to spread close to the rectal surface of the gland. Stages A and B cancers spanned a roughly comparable volume range, and both showed progressive dedifferentiation with increasing volume. It is proposed that stages A and B cancers are biologically similar malignancies, distinguished only by their site of origin. Prognosis for patients with stage A carcinoma probably is closely related to tumor volume and dedifferentiation, features that are not reliably estimated in tissue samples removed at operation for benign prostatic hyperplasia.


Assuntos
Adenocarcinoma/patologia , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/patologia , Adenocarcinoma/cirurgia , Humanos , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/cirurgia
14.
Br J Radiol ; 57(675): 241-5, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6697085

RESUMO

Radiation treatment fields have been established in 40 patients with carcinoma of the urinary bladder using a technique based on B-scan measurements of tumour dimensions and position. Three-dimensional data were obtained using omnidirectional calipers and the in-built measuring system of the scanner gantry, and by measurement from the recorded images. All measurements of the tumour dimensions and co-ordinates of the tumour centre were related to a fixed patient reference point. The ultrasound measurements were superimposed on to the AP and lateral planning radiographs after multiplication by the appropriate magnification factor. Ultrasound tomograms provided accurate data for radiotherapy planning and offer a convenient method for monitoring the response to treatment on follow-up.


Assuntos
Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico , Humanos , Radiografia , Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/radioterapia
17.
Clin Radiol ; 32(4): 413-9, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7249518

RESUMO

There are two types of extravasation into the renal sinus from the fornices of the calyces; one due to transudation through an intact mucosa and the other due to an actual defect in the calyx. It is suggested that extravasation from the fornices into the renal sinus can occur spontaneously in the absence of obstruction and without a rise in pressure. Truly spontaneous extravasation can occur whether ureteric compression is used or not.


Assuntos
Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Rim/diagnóstico por imagem , Adulto , Idoso , Cólica/diagnóstico por imagem , Feminino , Humanos , Cálices Renais/diagnóstico por imagem , Nefropatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Obstrução Ureteral/complicações
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