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2.
Phys Chem Chem Phys ; 18(5): 4221, 2016 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-26771962

RESUMEN

Correction for 'Singlet lifetime measurements in an all-proton chemically equivalent spin system by hyperpolarization and weak spin lock transfers' by Y. Zhang et al., Phys. Chem. Chem. Phys., 2015, 17, 24370-24375.

5.
Phys Chem Chem Phys ; 17(37): 24370-5, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26330001

RESUMEN

Hyperpolarized singlet states provide the opportunity for polarization storage over periods significantly longer than T1. Here, we show how the singlet state in a chemically equivalent proton spin system can be revealed by a weak power spin-lock. This procedure allowed the measurement of the lifetimes of the singlet state in protic solvents. The contributions of different intra- and intermolecular relaxation mechanisms to singlet lifetimes are investigated with this procedure.

6.
Rev Sci Instrum ; 82(9): 091301, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21974566

RESUMEN

The Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument is a millimeter-wave cryogenic receiver designed to observe galaxy clusters via the Sunyaev-Zel'dovich effect from the 12 m APEX telescope on the Atacama plateau in Chile. The receiver contains a focal plane of 280 superconducting transition-edge sensor (TES) bolometers instrumented with a frequency-domain multiplexed readout system. The bolometers are cooled to 280 mK via a three-stage helium sorption refrigerator and a mechanical pulse-tube cooler. Three warm mirrors, two 4 K lenses, and a horn array couple the TES bolometers to the telescope. APEX-SZ observes in a single frequency band at 150 GHz with 1' angular resolution and a 22' field-of-view, all well suited for cluster mapping. The APEX-SZ receiver has played a key role in the introduction of several new technologies including TES bolometers, the frequency-domain multiplexed readout, and the use of a pulse-tube cooler with bolometers. As a result of these new technologies, the instrument has a higher instantaneous sensitivity and covers a larger field-of-view than earlier generations of Sunyaev-Zel'dovich instruments. The TES bolometers have a median sensitivity of 890 µK(CMB)√s (NEy of 3.5 × 10(-4) √s). We have also demonstrated upgraded detectors with improved sensitivity of 530 µK(CMB)√s (NEy of 2.2 × 10(-4) √s). Since its commissioning in April 2007, APEX-SZ has been used to map 48 clusters. We describe the design of the receiver and its performance when installed on the APEX telescope.

8.
Afr J Paediatr Surg ; 7(3): 156-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20859019

RESUMEN

BACKGROUND: Colostomy site, which is a potentially contaminated wound, is traditionally closed with interrupted skin stitches and placement of intraperitoneal or parietal or both drains; often with poor cosmetic outcome in our country. This study aims at prospective evaluation of colostomy closure wounds by different techniques. PATIENTS AND METHODS: This study was carried out in all infants and children with colostomy (for different pathologies) admitted for colostomy closure in our institute from August 1, 2006 to February 29, 2008. Patients were divided into two groups: Group A with colostomy closure without any drain and subcuticular skin closure and Group B with colostomy closure with both intraperitoneal and parietal drain and interrupted skin closure. Patient's details, including age, sex, body weight, diagnosis, preoperative bowel preparation, peroperative antibiotics, postoperative wound infection, anastomotic leaks, duration of hospitalisation and postoperative follow-up for wound assessment, were recorded. By the end of February 2008, 151 cases of colostomy closure were recorded, 70 in Group A and 81 in Group B. RESULTS: Statistical analysis of the data showed no statistically significant difference in wound infection and anastomotic leak between the two groups. On postoperative follow-up, wound assessment showed significantly better cosmesis in the no drain subcuticular group. CONCLUSION: This study shows that closing colostomies without any drain and subcuticular skin closure does not result in any increased incidence of wound infection and has better cosmetic results.


Asunto(s)
Antiinfecciosos/uso terapéutico , Colostomía/efectos adversos , Infección de la Herida Quirúrgica/tratamiento farmacológico , Niño , Preescolar , Colostomía/métodos , Países en Desarrollo , Drenaje , Femenino , Estudios de Seguimiento , Humanos , Incidencia , India/epidemiología , Lactante , Masculino , Estudios Prospectivos , Distribución por Sexo , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Técnicas de Sutura , Resultado del Tratamiento , Cicatrización de Heridas
10.
J Cancer Res Ther ; 6(4): 585-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21358110

RESUMEN

AIM: To evaluate the integral dose to carotid vessels in extended field intensity modulated radiotherapy (IMRT) (including the lower neck nodes in IMRT field) and split field IMRT (using separate single anterior field to treat lower neck nodes) in cancer nasopharynx. MATERIALS AND METHODS: Dosimetric data from 10 patients of carcinoma nasopharynx, undergoing IMRT, were evaluated in this prospective study. The carotid vessels were contoured from sternoclavicular joints upto the base of skull. IMRT plans were generated for all patients with extended field and split field IMRT techniques using nine coplanar beams with 6 MV photons. A dose of 70 Gy to planning target volume (PTV) 70 Gy, 59.4 Gy to PTV 59.4 Gy and 54 Gy to PTV 54 Gy was delivered in 33 fractions. The dose constraints were similar for both the techniques. The integral dose to the carotid arteries was calculated as the mean dose times the volume (mean dose Χ volume) in units of liter-gray. RESULTS: The mean dose to the carotid vessels in the extended field IMRT was 63.88 ± 0.97 Gy (mean dose ± SD) and it was 64.43 ± 0.73 Gy for the split field technique. The integral dose in the extended field versus split field technique was 0.29 ± 0.0207 and 0.32 ± 0.0213 liter-gray, respectively. The difference was statistically significant (P < 0.013). CONCLUSIONS: Extended field IMRT delivers a slightly lower integral dose to carotid arteries in treatment of cancer nasopharynx while maintaining good dose homogeneity to the PTV 54 Gy and can be preferred over split field radiotherapy.


Asunto(s)
Arterias Carótidas/efectos de los fármacos , Neoplasias Nasofaríngeas/radioterapia , Adulto , Humanos , Dosificación Radioterapéutica
11.
J Cancer Res Ther ; 5(3): 161-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19841556

RESUMEN

Brain metastases constitute one of the most common distant metastases of cancer and are increasingly being detected with better diagnostic tools. The standard of care for solitary brain metastases with the primary disease under control is surgery followed by radiotherapy. Radiotherapy is also the primary modality for the treatment of multiple brain metastases, and improves both the quality of life and survival of patient. Unfortunately, more than half of these treated patients eventually progress leading to a therapeutic dilemma. Another course of radiotherapy is a viable but underutilized option. Reirradiation resolves distressing symptoms and has shown to improve survival with minimal late neurotoxicity. Reirradiation has conventionally been done with whole brain radiotherapy, but now studies with stereotactic radiosurgery have also shown promising results. In this review, we focus on reirradiation as a treatment modality in such patients. We performed a literature search in MEDLINE (www.pubmed.org) with key words brain metastases, reirradiation, whole brain radiotherapy, stereotactic radiosurgery, interstial brachytherapy, and brain. The search was limited to the English literature and human subjects.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Braquiterapia , Irradiación Craneana/métodos , Humanos , Calidad de Vida , Radiocirugia , Dosificación Radioterapéutica , Radioterapia Adyuvante , Retratamiento , Análisis de Supervivencia , Resultado del Tratamiento
12.
J Cancer Res Ther ; 5(2): 78-84, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19542662

RESUMEN

AIM: The main objective of this study was to analyze the radiobiological effect of different treatment strategies on high-risk prostate adenocarcinoma. MATERIALS AND METHODS: Ten cases of high-risk prostate adenocarcinoma were selected for this dosimetric study. Four different treatment strategies used for treating prostate cancer were compared. Conventional four-field box technique covering prostate and nodal volumes followed by three-field conformal boost (3D + 3DCRT), four-field box technique followed by intensity-modulated radiotherapy (IMRT) boost (3D + IMRT), IMRT followed by IMRT boost (IMRT + IMRT), and simultaneous integrated boost IMRT (SIBIMRT) were compared in terms of tumor control probability (TCP) and normal tissue complication probability (NTCP). The dose prescription except for SIBIMRT was 45 Gy in 25 fractions for the prostate and nodal volumes in the initial phase and 27 Gy in 15 fractions for the prostate in the boost phase. For SIBIMRT, equivalent doses were calculated using biologically equivalent dose assuming the alpha/beta ratio of 1.5 Gy with a dose prescription of 60.75 Gy for the gross tumor volume (GTV) and 45 Gy for the clinical target volume in 25 fractions. IMRT plans were made with 15-MV equispaced seven coplanar fields. NTCP was calculated using the Lyman-Kutcher-Burman (LKB) model. RESULTS: An NTCP of 10.7 +/- 0.99%, 8.36 +/- 0.66%, 6.72 +/- 0.85%, and 1.45 +/- 0.11% for the bladder and 14.9 +/- 0.99%, 14.04 +/- 0.66%, 11.38 +/- 0.85%, 5.12 +/- 0.11% for the rectum was seen with 3D + 3DCRT, 3D + IMRT, IMRT + IMRT, and SIBIMRT respectively. CONCLUSIONS: SIBIMRT had the least NTCP over all other strategies with a reduced treatment time (3 weeks less). It should be the technique of choice for dose escalation in prostate carcinoma.


Asunto(s)
Adenocarcinoma/radioterapia , Probabilidad , Neoplasias de la Próstata/radioterapia , Humanos , Masculino , Radioterapia/métodos , Dosificación Radioterapéutica
13.
Indian J Chest Dis Allied Sci ; 51(2): 103-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19445446

RESUMEN

Management of locally advanced non-small cell lung cancer is associated with a poor overall survival using concurrent chemoradiotherapy. Therefore, newer approaches to treatment which enable dose escalation are warranted. Interstitial brachytherapy in lung is a new emerging concept with many distinct advantages. We report here a case of locally advanced non-small cell lung cancer with residual disease after conventional treatment. The patient was successfully treated using percutaneous interstitial brachytherapy and is disease-free at 18-month follow-up.


Asunto(s)
Braquiterapia/métodos , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Quimioterapia Adyuvante , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica
14.
Mymensingh Med J ; 18(1): 67-71, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19182753

RESUMEN

In Nephrotic Syndrome the amount of protein excretion is a reflection of activity of disease. Quantitative measurement of proteinuria by a 24-hour urine collection has been the accepted method of evaluation. Recent studies have shown that calculation of protein/creatinine ratio in a spot urine sample correlates well with the 24-hour urine protein (24-HUP) excretion. A study was conducted to compare the accuracy of a spot urinary protein/creatinine ratio (P/C ratio) and urinary dipstick with the 24-hour urine protein. Fifty two samples from 26 patients of nephrotic syndrome were collected. This included a 24-hour urine sample followed by the next voided random spot sample. The protein/creatinine ratio was calculated and dipstick was performed on the spot sample. This was compared with the 24-hour urine protein excretion. The correlation between the three samples was statistically highly significant (p<0.001) for all levels of proteinuria. The normal value of protein/creatinine ratio in Indian children was also estimated on 50 normal children admitted in the ward without any renal diseases calculated to be 0.053 (SE of mean+/-0.003).


Asunto(s)
Creatinina/orina , Síndrome Nefrótico/orina , Proteinuria/orina , Factores de Edad , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Pruebas de Función Renal , Masculino , Síndrome Nefrótico/diagnóstico , Síndrome Nefrótico/fisiopatología , Estudios Prospectivos , Proteinuria/diagnóstico , Proteinuria/fisiopatología , Sensibilidad y Especificidad , Estadística como Asunto , Factores de Tiempo
15.
J Cancer Res Ther ; 4(3): 126-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18923205

RESUMEN

AIMS: Radiotherapy forms an integral part of breast-conserving treatment in early-stage breast cancer. Subcutaneous fibrosis of the treated breast is an important late effect in whole-breast irradiation. The aim of this study was to compare the normal tissue complication probability (NTCP) for radiation-induced fibrosis in treated breast using accelerated partial-breast irradiation (APBI) vs conventional treatment. MATERIALS AND METHODS: Ten postoperative early-stage breast cancer patients (T1N0M0) were included in this dosimetric analysis. APBI treatment was planned using conformal radiotherapy technique and conventional treatment plans included two tangential portals. All the APBI treatment plans were made with five non-coplanar beams with 6 MV photons. The prescription dose was 38 Gy in 10 fractions for the APBI treatments and 50 Gy in 25 fractions, followed by a boost dose of 16 Gy in 8 fractions, for the conventional treatments. We used Lyman's relative-seriality model and the breast fibrosis NTCP model fitting parameters for the study. RESULTS: The equivalent uniform dose (EUD) was 30.09 Gy and 50.79 Gy in APBI and conventional treatment, respectively. The mean NTCP values for ipsilateral breast fibrosis in APBI and conventional treatment were 0.51 and 25.66%, respectively. Using the paired t-test, a statistically significant difference was seen in the breast fibrosis NTCP values for APBI vs conventional treatment (P < 0.001). CONCLUSIONS: APBI reduces the ipsilateral breast fibrosis compared to conventional whole-breast treatment in early-stage breast cancer.


Asunto(s)
Neoplasias de la Mama/radioterapia , Mama/patología , Mama/efectos de la radiación , Radioterapia/efectos adversos , Radioterapia/métodos , Neoplasias de la Mama/cirugía , Terapia Combinada , Femenino , Fibrosis/etiología , Humanos , Mastectomía Segmentaria , Dosificación Radioterapéutica
17.
Allergy ; 63(9): 1211-7, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18307574

RESUMEN

BACKGROUND: Filaggrin (FLG) null mutations are important genetic predisposing factors for atopic asthma and have recently been shown to influence controller and reliever medication needs in asthmatic children. Our objective was to study the role of FLG null alleles in asthma exacerbations. METHODS: FLG mutations R501X and 2282del4 were assayed in 1135 individuals ranging from 3 to 22 years old with asthma from Tayside and Dumfries, Scotland. Asthma exacerbations over the previous 6 months were also studied. RESULTS: The FLG mutations were significantly associated with greater risk of exacerbations in children with asthma. Exacerbations were significant for the R501X but not the 2282del4 mutation and the combined genotype compared to the wild-type with odds ratios of 1.97 (95% CI, 1.19-3.22; P = 0.009) and 1.61 (95% CI, 1.08-2.40; P = 0.021), respectively. Individuals with FLG null alleles were more likely to require oral steroids (31.4%vs 19.5%; OR = 1.89; P = 0.021) for their exacerbations. There was also a 1.71-fold increased risk (42.6%vs 30%; P = 0.041) of school absence owing to asthma exacerbations in asthmatic individuals with FLG null mutation. On sub-group analysis, the effect of FLG mutations on asthma exacerbations is significant (P = 0.045) only for participants with relatively mild asthma controlled on inhaled steroids, with inhaled albuterol according to need. CONCLUSION: In addition to their effect on asthma medication requirements reported previously, there is an association between the presence of FLG null mutations and the risk of asthma exacerbations in asthmatic children and young adults.


Asunto(s)
Asma/tratamiento farmacológico , Asma/genética , Glucocorticoides/administración & dosificación , Proteínas de Filamentos Intermediarios/genética , Adolescente , Niño , Preescolar , Proteínas Filagrina , Humanos , Masculino , Mutación , Índice de Severidad de la Enfermedad , Adulto Joven
18.
J Med Syst ; 31(4): 247-53, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17685148

RESUMEN

For a given DNA sequence, it is well known that pair wise alignment schemes are used to determine the similarity with the DNA sequences available in the databanks. The efficiency of the alignment decides the type of amino acids and its corresponding proteins. In order to evaluate the given DNA sequence for its proteomic identity, a pattern matching approach is proposed in this paper. A block based semi-global alignment scheme is introduced to determine the similarity between the DNA sequences (known and given). The two DNA sequences are divided into blocks of equal length and alignment is performed which minimizes the computational complexity. The efficiency of the alignment scheme is evaluated using the parameter, percentage of similarity (POS). Four essential DNA version of the amino acids that emphasize the importance of proteomic functionalities are chosen as patterns and matching is performed with the known and given DNA sequences to determine the similarity between them. The ratio of amino acid counts between the two sequences is estimated and the results are compared with that of the POS value. It is found from the experimental results that higher the POS value and the pattern matching higher are the similarity between the two DNA sequences. The optimal block is also identified based on the POS value and amino acids count.


Asunto(s)
Algoritmos , Bases de Datos Genéticas/estadística & datos numéricos , Reconocimiento de Normas Patrones Automatizadas/métodos , Alineación de Secuencia/métodos , Homología de Secuencia de Ácido Nucleico , Humanos
20.
Immunol Invest ; 35(2): 209-25, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16698678

RESUMEN

Cases of Acquired Aplastic Anaemia (AAA) in patients with a long history of pesticide exposure from agricultural fields have been investigated in our laboratory using an immunological approach. These patients showed moderate to severe degrees of bone marrow aplasia as a result of 9-12 years protracted exposure to pesticides which were mainly comprised of organophosphorous and organochloride compounds. The bone marrow aspirate culture was found to be severely deficient both in terms of differentiation and proliferation, and cell mediated immune function (CMI). We attempted ex vivo manipulation of the bone marrow population of patients in two different protocols: in one, stem cell factor (SCF), interleukin-3 (IL-3), and granulocyte-colony stimulating factor (G-CSF) were administered and, in the second set, cord blood-derived plasma factors (CBPF) were supplemented to evaluate the effects, if any. Simultaneously, two control groups including one for healthy normal control (N) and the second, for non-pesticide induced aplastic anaemia group of patients (NPAA) was also investigated for all the above parameters. Active colony formation and improved cellular immune activity (CMI) was observed more frequently in the CBPF treated group rather than that in the cytokine treated group. Surprisingly, administration of cytokines in the first set and CBPF in the second set triggered CD34 (+) cell generation as revealed through flow cytometric analysis (FACS). The effect was more pronounced in the second set. Investigations carried out with NPAA showed relatively insignificant effects with both cytokine and CBPF set up. The investigations indicated that AAA as induced by pesticides could be therapeutically manipulated by exogenous cytokines and growth factors and, more efficiently, by CBPF by way of immunopotentiation through microenvironmental supplementation.


Asunto(s)
Anemia Aplásica/inducido químicamente , Anemia Aplásica/inmunología , Células de la Médula Ósea/inmunología , Sangre Fetal/inmunología , Plaguicidas/envenenamiento , Adolescente , Adulto , Enfermedades de los Trabajadores Agrícolas/sangre , Enfermedades de los Trabajadores Agrícolas/inducido químicamente , Enfermedades de los Trabajadores Agrícolas/inmunología , Anemia Aplásica/sangre , Células de la Médula Ósea/citología , Procesos de Crecimiento Celular/inmunología , Pruebas Inmunológicas de Citotoxicidad , Femenino , Sangre Fetal/química , Humanos , Recién Nacido , Masculino , Nitroazul de Tetrazolio , Fagocitosis , Embarazo
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