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1.
Phys Rev Lett ; 127(24): 243601, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34951800

RESUMO

Quantum optical measurement techniques offer a rich avenue for quantum control of mechanical oscillators via cavity optomechanics. In particular, a powerful yet little explored combination utilizes optical measurements to perform heralded non-Gaussian mechanical state preparation followed by tomography to determine the mechanical phase-space distribution. Here, we experimentally perform heralded single-phonon and multiphonon subtraction via photon counting to a laser-cooled mechanical thermal state with a Brillouin optomechanical system at room temperature and use optical heterodyne detection to measure the s-parametrized Wigner distribution of the non-Gaussian mechanical states generated. The techniques developed here advance the state of the art for optics-based tomography of mechanical states and will be useful for a broad range of applied and fundamental studies that utilize mechanical quantum-state engineering and tomography.

2.
Phys Rev Lett ; 126(3): 033601, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543972

RESUMO

Adding or subtracting a single quantum of excitation to a thermal state of a bosonic system has the counter-intuitive effect of approximately doubling its mean occupation. We perform the first experimental demonstration of this effect outside optics by implementing single-phonon addition and subtraction to a thermal state of a mechanical oscillator via Brillouin optomechanics in an optical whispering-gallery microresonator. Using a detection scheme that combines single-photon counting and optical heterodyne detection, we observe this doubling of the mechanical thermal fluctuations to a high precision. The capabilities of this joint click-dyne detection scheme adds a significant new dimension for optomechanical quantum science and applications.

3.
J Clin Pathol ; 52(11): 865-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10690184

RESUMO

A 67 year old man with myelodysplasia was admitted as an emergency with a six week history of rectal bleeding and diarrhoea. Barium enema showed an irregular polypoid filling defect in the lateral wall of the proximal rectum near the rectosigmoid junction. Histology showed this to be a granulocytic sarcoma (extramedullary granulocytic leukaemia; chloroma) infiltrating the bowel. A low index of suspicion of this lesion results in an incorrect diagnosis in many such cases. A chloroacetate esterase immunoperoxidase stain will confirm the granulocytic nature of the tumour cells.


Assuntos
Leucemia Mieloide/complicações , Síndromes Mielodisplásicas/complicações , Neoplasias Retais/complicações , Idoso , Humanos , Imuno-Histoquímica , Leucemia Mieloide/patologia , Masculino , Síndromes Mielodisplásicas/patologia , Neoplasias Retais/patologia
4.
Ann R Coll Surg Engl ; 80(6): 433-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10209415

RESUMO

The role of preoperative localisation tests before initial neck exploration for primary hyperparathyroidism (PHP) remains controversial, as does the optimal surgical approach. We report our experience with preoperative ultrasound (US) and the operative management of sporadic PHP between 1990 and 1995. Preoperative US was carried out by an experienced radiologist. Three surgeons adopted a policy of 'selective' US-guided unilateral neck exploration (UNE); the fourth surgeon performed routine bilateral neck exploration (BNE). There were 72 patients: 26 men and 46 women, with a mean age of 57.4 +/- 12.5 years (range 21-80 years). All patients underwent initial neck exploration for 'sporadic' PHP, of whom 63 had preoperative US. This was positive in 52 patients; 27 of whom underwent a UNE, 23 had a BNE, and two patients had a UNE converted to a BNE. Patients with 'negative' US (n = 11), and those receiving no preoperative localisation test (n = 90) underwent a BNE. The sensitivity, specificity and accuracy of US were 80% (52/65), 100% (61/61), and 90% (113/126), respectively. Comparable success rates were achieved (BNE: 97% (33/34) vs UNE: 93% (27/29), P < 0.05), with very low morbidity. Failures with the scan-guided UNE were caused by missed contralateral adenomas. An experienced radiologist and a low incidence of multiglandular disease (MGD) are essential prerequisites for the scan-guided unilateral approach. An experienced surgeon, on the other hand, is the only prerequisite for the 'gold standard' bilateral approach.


Assuntos
Hiperparatireoidismo/diagnóstico por imagem , Hiperparatireoidismo/cirurgia , Adenoma/complicações , Adenoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Hiperparatireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/diagnóstico por imagem , Complicações Pós-Operatórias , Sensibilidade e Especificidade , Ultrassonografia
6.
Br J Obstet Gynaecol ; 101(10): 888-93, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7999691

RESUMO

OBJECTIVE: To assess the prognostic significance of presentation serum albumin, clinical stage and CA125 levels in ovarian cancer. DESIGN: Retrospective analysis of data using a Cox proportional hazards model. SETTING: A district general hospital oncology unit. SUBJECTS: One hundred and fourteen consecutive patients with epithelial ovarian cancer. INTERVENTIONS: Cytotoxic chemotherapy and surgery. MAIN OUTCOME MEASURE: Survival. RESULTS: A linear increase in risk was observed with high log CA125 (P < 0.0001) and with low albumin (P < 0.0001). In late stage patients (III and IV) albumin is the best predictor of survival (P = 0.0006). The presence of ascites, blood transfusion, type of surgery or chemotherapy did not improve the predictive model. CONCLUSIONS: CA125 and albumin can be used to identify prognostic subgroups independently of stage. Albumin alone can also be used as a predictor of survival. A simple classification of patients into three groups based on serum albumin of 41 g/l or more, 35 to 40 g/l and 34 g/l or less provides a clear separation of survival curves in the present group of patients.


Assuntos
Antígeno Ca-125/sangue , Neoplasias Ovarianas/mortalidade , Albumina Sérica/análise , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/cirurgia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida
7.
ASAIO J ; 38(3): M519-23, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1457915

RESUMO

Venous pressure measured by the dialyzer is an unreliable measure of intra-access venous pressure. During dialysis and zero extracorporeal blood flow, intra-access venous limb pressure (VPd) was measured directly 401 times in 133 subjects using a high flow "in-line" three-way stopcock adjacent to the venous return needle. Subjects with systolic VPd/systolic blood pressure (BP) > or = 0.4, inadequate blood flow, or edema in the access extremity were referred for angiography. Percent diameter lumen reduction by a stenosis (%D) > 50% was considered hemodynamically significant. The authors did 138 angiograms. It was found that VPd/BP increased with %D in both ePTFE bridge grafts and native fistulae. Measurements of venous limb VP/BP taken at the time of dialysis and at the time of angiography did not differ (n = 55). On 80 occasions, accesses had significant stenoses. The overall sensitivity of VPd/BP in ePTFE bridge grafts was 91% and specificity 91%. False negative results occurred in seven of 24 native and eight of 114 ePTFE graft studies; 14 of 15 patients had arm swelling caused by central stenosis. Recirculation > 15% was more sensitive (71%) in detecting stenosis in native accesses than was intra-access pressure. It was concluded that VPd/BP > 0.4 is a useful, sensitive, and specific criteria for detecting synthetic bridge graft accesses at risk for thrombosis.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Pressão Venosa/fisiologia , Angiografia , Constrição Patológica , Humanos , Diálise Renal/efeitos adversos , Trombose/diagnóstico por imagem , Trombose/etiologia
8.
Br J Cancer ; 59(5): 797-800, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2736216

RESUMO

Serum levels of mucin-like carcinoma associated antigen (MCA) were measured in 80 healthy women, 109 patients with breast cancer at presentation and in samples taken from 45 patients with active metastatic breast cancer. The MCA levels in controls had an upper limit of normal of 19.6 U ml-1 in post-menopausal and 16.4 U ml-1 in premenopausal women. The levels at presentation in stages I and II and III were not significantly different from the post-menopausal controls. Longitudinal studies over 5-9 years in 20 patients with stage I and II disease who had remained tumour-free showed a narrow MCA range for each individual patient, but the mean and range of a single measurement in a further 63 of these patients were similar to those of the normal controls. Rising MCA levels occurred in 12/14 patients who developed metastases in 2-8 years after surgery, but local recurrence was not associated with a rise of MCA. Eighty per cent of patients with active metastatic disease had MCA levels greater than 15 U ml-1. MCA levels fell during clinical responses to therapy in metastatic cancer. In the context of follow-up serum MCA levels appear to be a sensitive indicator of metastatic disease; caution is required in the interpretation of isolated measurements.


Assuntos
Antígenos de Neoplasias/análise , Antígenos Glicosídicos Associados a Tumores , Biomarcadores Tumorais/sangue , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
11.
Br J Surg ; 67(7): 528-30, 1980 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7417757

RESUMO

Occult rectal prolapse is a condition of young adults which causes problems in diagnosis. Symptoms consist of tenesmus and the passage of blood and mucus associated with constipation and straining at stool. The rectal prolapse often remains unrecognized for a long time because demonstration of the prolapse is difficult. There are characteristic changes in the rectum on clinical examination and these should alert the clinician to the diagnosis. Treatment of the prolapse relieves the symptoms.


Assuntos
Prolapso Retal/diagnóstico , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prolapso Retal/patologia , Prolapso Retal/terapia , Sigmoidoscopia , Fatores de Tempo
13.
Clin Radiol ; 30(2): 139-47, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-86404

RESUMO

Estracyt, a conjugate of an alkylating agent with an oestrogenic sterol, was given in a dose of 420 mg daily to a group of 44 postmenopausal patients with very advanced breast carcinoma. Thirty-eight of these were in relapse following chemotherapy and 32 had evidence of distant metastases. Seventeen patients had an objective response and marked or complete alleviation of symptoms, four others had a useful symptomatic response but no beneficial effect was observed in the remainder. Three who had shown no response to previous oestrogen therapy also failed to respond to Estracyt as did all nine patients with hepatic metastases. Oestrogen receptor status and age within the postmenopausal group seemed to have no bearing on the result. Side-effects were minimal with nausea in 18 patients but in only two did this necessitate withdrawal of the drug. Bone marrow depression did not occur. Changes in acute-phase reactant proteins suggested that part of the Estracyt was de-esterified in the liver liberating oestrone but the low incidence of vaginal haemorrhage and the recalcification of bony metastases suggested that on the whole Estracyt behaves as an anti-oestrogen as well as an antimitotic.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Idoso , Neoplasias da Mama/análise , Estramustina/uso terapêutico , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Metástase Neoplásica , Cuidados Paliativos , Receptores de Estrogênio/análise , Fatores de Tempo
15.
Br J Surg ; 64(2): 134-8, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-407964

RESUMO

The outcome in 254 patients with all stages of breast cancer treated by combination chemotherapy is presented. All the patients were treated 10 or more years ago. The 10-year survival rate for Stages I and II combined is 60 per cent, in Stage III 19 per cent and in Stage IV 3 per cent. The combined rate in Stages I and II differed markedly according to hormonal status. In premenopausal patients the rate was 84 per cent compared with 42 per cent in postmenopausal patients.


Assuntos
Androgênios/uso terapêutico , Neoplasias da Mama/mortalidade , Tiotepa/uso terapêutico , Adulto , Idoso , Androgênios/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Combinada , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Tiotepa/administração & dosagem , Fatores de Tempo
17.
Br Med J ; 1(5793): 142-4, 1972 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-5007839

RESUMO

A retrospective survey of 4,026 patients having truncal vagotomy and pyloroplasty for duodenal ulceration showed a mortality rate of 1.4% (55 patients). On analysis the commonest causes of death were found to be bronchopneumonia 37% (18 patients) and sepsis 20% (10 patients). More than half of the deaths occurred in patients aged over 50.


Assuntos
Úlcera Duodenal/cirurgia , Piloro/cirurgia , Vagotomia/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Broncopneumonia/mortalidade , Criança , Pré-Escolar , Úlcera Duodenal/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sepse/mortalidade , Infecção da Ferida Cirúrgica/mortalidade
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