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1.
Science ; 269(5224): 671-4, 1995 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-7624796

RESUMO

An artificial receptor has been designed to bind creatinine with a color change (chromogenic response) caused by proton transfer from one end of the receptor to the other. The receptor was synthesized and found to extract creatinine from water into chlorocarbon solvents. The color change in the organic layer is specific for creatinine relative to other organic solutes, and it is selective for creatinine relative to sodium, potassium, and ammonium ions. The chromogenic mechanism is revealed by x-ray crystal structures of creatinine, the free receptor, and the complex, showing "induced fit" binding resulting from electronic complementarity between host and guest.


Assuntos
Acridinas/síntese química , Compostos Cromogênicos/síntese química , Creatinina/análise , Naftiridinas/síntese química , Acridinas/química , Sítios de Ligação , Compostos Cromogênicos/química , Creatinina/sangue , Creatinina/química , Cristalização , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Hidrogênio/química , Ligação de Hidrogênio , Naftiridinas/química , Oxigênio/química , Prótons
2.
Hepatogastroenterology ; 48(41): 1308-11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11677952

RESUMO

BACKGROUND/AIMS: At present a pancreatic pseudocyst puncture guided by ultrasonography is a treatment of choice in the majority of hospitals. A classical two-dimensional sonography is usually implemented in these cases. However, its shortcomings, mainly in differential diagnosis, are acknowledged by most physicians. The real time monitoring of a fine-needle pseudocyst procedure by two-dimensional ultrasonography is of questionable reliability. In our study we evaluated the usefulness of three-dimensional sonography in the percutaneous fine-needle pancreatic pseudocyst puncture. METHODOLOGY: We examined fifty-two patients diagnosed as having pancreatic pseudocysts on the basis of clinical symptoms and two-dimensional ultrasonography findings. Then the decision to qualify certain patients for the percutaneous fine-needle aspiration guided by ultrasonography was made on the basis of two- and three-dimensional scan results. The next step in our investigation was to implement color Doppler in order to visualize all blood vessels at the planned biopsy site. Three-dimensional sonography was used to monitor the tip of the needle making its way to the pancreatic pseudocyst and later inside the fluid collection. RESULTS: Pancreatic pseudocysts were diagnosed in all of the 52 cases. Three-dimensional sonography was more precise in visualizing the shape and size than two-dimensional ultrasound scans. CONCLUSIONS: Three-dimensional presentation can better visualize irregular shapes, local thickenings, and calcification of pseudocyst walls than classical two-dimensional ultrasound scans. The use of subtraction in three-dimensional scans of blood vessels increases the safety in performing biopsies. It makes the aspiration of cytologic materials much safer to perform. In our study we have shown that three-dimensional sonography collects extremely useful information about the status of the pseudocyst structure and it should become a complementary method to classical ultrasonography. This technique when used on a routine basis ought to help us change the inclusion criteria for guided biopsies.


Assuntos
Biópsia por Agulha/instrumentação , Imageamento Tridimensional , Pseudocisto Pancreático/terapia , Punções/instrumentação , Ultrassonografia Doppler em Cores , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/irrigação sanguínea , Pâncreas/patologia , Pseudocisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/patologia
3.
Kardiol Pol ; 35(11): 284-91; discussion 292, 1991.
Artigo em Polonês | MEDLINE | ID: mdl-1800822

RESUMO

Emergency coronary bypass for cardiogenic shock has been associated with a high operative mortality. From February 1986 through October 1989, 40 patients with acute myocardial infarction were operated. Ten pts (25%) were in shock despite intensive treatment (intra-aortic balloon pump in 4, catecholamines in 10). Seven pts. required cardiopulmonary resuscitation before operations. After operations 66% of the patients required catecholamine support and 60% were treated with intra-aortic balloon pump. There were three (30%) hospital deaths (one in the operating room due to acute cardiac failure). Follow-up (100%),(mean 26 months) revealed one late death--39 months after operations. In functional class I were 2 patients, II--one, and III--two pts. One pt is in group IV (transplant candidate). Myocardial infarction complicated by cardiogenic shock can produce a mortality rate in excess of 85%. Contemporary medical management has had little effect on mortality, hence effective surgical therapy has evolved for this lesion.


Assuntos
Ponte de Artéria Coronária/métodos , Infarto do Miocárdio/cirurgia , Complicações Pós-Operatórias/etiologia , Choque Cardiogênico/cirurgia , Idoso , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Morte Súbita/etiologia , Emergências , Parada Cardíaca Induzida , Humanos , Cuidados Intraoperatórios , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Reperfusão Miocárdica , Complicações Pós-Operatórias/mortalidade , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade , Fatores de Tempo
4.
Phys Rev Lett ; 102(15): 152701, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19518626

RESUMO

The A/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at SIS. A stable beam of (124)Sn and radioactive beams of (124)La and (107)Sn at 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. Chemical freeze-out temperatures are found to be nearly invariant with respect to the A/Z of the produced spectator sources, consistent with predictions for expanded systems. Small Coulomb effects (DeltaT approximately 0.6 MeV) appear for residue production near the onset of multifragmentation.

5.
Clin Chem ; 39(9): 1820-4, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8375054

RESUMO

We report a new single-reagent colorimetric assay for the determination of calcium in serum. The assay is based on a novel chromogenic tetracarboxylic acid chelating agent. The method has several advantages over the o-cresolphthalein complexone (CPC) method, including improved linearity, better accuracy, increased stability, and lower working pH (9.0). The calibration curve for the assay is linear up to 4 mmol/L. The results for 47 patients' samples correlated well with results obtained with an Instrumentation Laboratory atomic absorption spectrophotometer. The mean (+/- SD) calcium values for the new method were 2.27 +/- 0.06 mmol/L and 2.26 +/- 0.05 mmol/L for the comparison method. The on-system stability of the reagents is 1 week vs 8 h for the CPC method.


Assuntos
Cálcio/sangue , Quelantes/síntese química , Compostos Cromogênicos/síntese química , Colorimetria/métodos , Humanos , Sensibilidade e Especificidade
6.
Clin Chem ; 38(9): 1654-7, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1525993

RESUMO

We report a colorimetric method for determining lithium in blood serum without sample pretreatment or solvent-extraction steps. The method is based on a novel chromogenic ionophore that exhibits exceptionally high selectivity (much greater than 4000:1) for lithium over sodium. The standard curve for the method is linear up to 3.5 mmol/L and exceeds the therapeutic range for lithium. The results for 57 patients' samples correlated well with results obtained with an Instrumentation Laboratory flame photometer (r = 0.97).


Assuntos
Colorimetria/métodos , Lítio/sangue , Etilenoglicóis/química , Humanos , Ionóforos/química , Reprodutibilidade dos Testes , Tensoativos
7.
J Anim Breed Genet ; 114(1-6): 69-78, 1997 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21395804

RESUMO

SUMMARY: Two different reciprocal translocations, rcp (8;14) (p21;q25) and rcp (7;13) (q13;q46), were described for the first time in Poland in the Polish Landrace and Duroc pigs. Observation of synaptonemal complexes showed the presence of a quadrivalent composed of translocational chromosomes and their homologues. Individuals carrying translocations were characterized by normal external appearance and correct semen parameters. Analysis of fertility made on the basis of litter size demonstrated that fertility decreased by 25% in the carrier of translocation rcp (8;14) and by 52% in the carrier of translocation rcp (7;13). ZUSAMMENFASSUNG: Zum erste mal festgestelte gegenseitige Translokationen bei Schweine in Polen Bein Polnischen Landras und Duroc Schweinen wurden zum erstenmal in Polen, zwei verschiedene reciproke Translokationen-rcp (8;14) (p21;q25) und rcp (7;13) (q13;q46)-festgestellt. Anhand der Beobachtungen des Synaptonemal Complex wurde die Anwesenheit eines Tetravalent nachgewiesen, welches aus Translokationschromosomen und seinen Homologen zusammengesetzt ist. Die Translokationstiere hatten normale Exterieur und Spermaparameter. Aufgrund der Fortpflanzungsergebmissen wurden verminderte Fruchtbarkeit bei Translokationstieren rcp (8;14)-um 25% und bei Translokationstieren rcp (7;13)-um 52% festgestellt. RÉSUMÉ: Les translocations réciproques identifiées pour la prèmière fois chez les porcs levés en Pologne Chez les porcs des races Landrace et Duroc on a constaté, pour la première fois en Pologne deux translocations réciproques différentes-rcp (8;14) (p21;q25) ainsi que rcp (7;13) (q13;q46). L'observation des complexes synaptonémals a manifesté la présence du quadrivalent composé de chromosomes de translocation et de leurs homologes. Les animaux-les porteurs de la translocation ont se caractérisé par l'extérieur normal et par les paramètres réguliers du sperme. L'analyse de la fertilité expérimenté selon de la taille des portées a démontré la réduction de la fertilité pour le porteur de la translocation rcp (8;14) à 25% cependant pour les porteurs de la translocation rcp (7;13) à 52%.

8.
Clin Chem ; 34(9): 1709-12, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3416420

RESUMO

We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Compostos Cromogênicos , Éteres de Coroa , Ionóforos , Potássio/sangue , Sódio/sangue , Espectrofotometria/métodos , Compostos Bicíclicos com Pontes , Quelantes , Éteres Cíclicos , Humanos , Controle de Qualidade , Valores de Referência
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