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1.
J Ultrasound Med ; 20(8): 821-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11503918

RESUMO

OBJECTIVE: To determine whether there is a relationship between gray scale or Doppler characteristics of the corpus luteum and first-trimester pregnancy outcome. METHODS: We conducted a prospective study of patients with spontaneous singleton pregnancies between 5 and 8 weeks' gestation. The corpus luteum size, sonographic appearance, resistive index, and peak systolic velocity were measured on transvaginal sonography. Maternal use of exogeneous progesterone was recorded. Only patients with known first-trimester outcome were included. RESULTS: There were 201 study patients. The corpus luteum could be visualized in 197 (98%) and had a mean +/- SD size of 1.9 +/- 0.6 cm, a mean resistive index of 0.50 +/- 0.08, and a peak systolic velocity of 20.5 +/- 11.2 cm/s. There were 151 first-trimester survivors (75.1 %) and 50 spontaneous losses (24.9%). In a comparison of the survivors and losses, there was no significant difference in mean corpus luteum size (1.9 versus 1.7 cm; P = .10, t test), mean resistive index (0.50 versus 0.50; P = .71, t test), peak systolic velocity (21 versus 19 cm/s; P = .29, t test), or sonographic appearance (P = .78, chi2 test). The lack of association between corpus luteum characteristics and outcome persisted when cases were stratified by progesterone use and the presence or absence of a heartbeat on the study sonogram. CONCLUSION: There is no apparent relationship between the characteristics of the corpus luteum and first-trimester pregnancy outcome.


Assuntos
Corpo Lúteo/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal , Corpo Lúteo/anatomia & histologia , Feminino , Humanos , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Progesterona/farmacocinética , Estudos Prospectivos , Reologia
2.
J Ultrasound Med ; 20(3): 263-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11270531

RESUMO

We sought to assess the sonographic findings and postnatal outcome in fetuses with the prenatal diagnosis of asymmetric hydrocephalus. The sonograms from cases of asymmetric hydrocephalus diagnosed prenatally at our institution were reviewed. Postnatal outcome was obtained from maternal, neonatal, and pediatric records. Fourteen fetuses at 17.3 to 38.9 weeks' gestational age on prenatal sonography had a maximum ventricular measurement of 10.2 to 48.8 mm, with the degree of asymmetry ranging from 2.2 to 27.3 mm. Thirteen of 14 had a normal-sized contralateral ventricle. Other fetal anomalies identified at sonography included Dandy-Walker malformation, intraventricular hemorrhage, porencephalic cyst, hydronephrosis, pleural effusion, and mild dilatation of a renal pelvis. Eleven fetuses had follow-up prenatal sonography. Among these, ventricular dilatation resolved in 5, remained the same in 3, increased in 2, and decreased in 1. Postnatal outcome was normal in 6 cases (43%) and abnormal in 8 (57%), including 2 cases of in utero intracranial hemorrhage, 2 with congenital syndromes, 1 with an imperforate foramen of Monro, 1 with tuberous sclerosis, 1 with developmental delays, and 1 with cerebral palsy. Asymmetric unilateral hydrocephalus appears to represent an entity different from bilateral hydrocephalus in that there is less risk of perinatal death, there are fewer associated anomalies, and the overall prognosis is better. Outcome may be normal, but fetuses with increasing unilateral ventriculomegaly and cases associated with other brain abnormalities tend to have a poor neurologic outcome.


Assuntos
Ventrículos Cerebrais/anormalidades , Ventrículos Cerebrais/diagnóstico por imagem , Hidrocefalia/diagnóstico por imagem , Ultrassonografia Pré-Natal , Anormalidades Múltiplas , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez
3.
JAMA ; 281(17): 1638-41, 1999 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10235159

RESUMO

CONTEXT: An increasing number of nonpalpable abnormalities requiring breast biopsy are being identified due to the widespread use of screening mammography. Large-core needle biopsy (LCNB) has become an alternative to surgical excision. OBJECTIVE: To determine whether LCNB is a safe and accurate technique to evaluate nonpalpable abnormalities found on breast imaging studies. DESIGN AND SETTING: Case series at an institutional referral center from August 1, 1991, to December 31, 1997. PATIENTS: A total of 1643 women with 1 or more suspicious breast abnormalities received LCNBs (n = 1836 lesions). INTERVENTION: The LCNB of the breast uses a 14- or 11-gauge needle with stereotactic localization or ultrasound guidance. MAIN OUTCOME MEASURE: Utility and potential limitations of LCNB compared with the criterion standard, surgical excision after wire localization. RESULTS: Of the 1836 breast lesions sampled, 444 (24%) were found to be malignant. A total of 412 (22%) were found to be malignant on the initial LCNB and 202 repeat biopsies yielded 32 additional malignancies. Complications were infrequent: 1 patient experienced a superficial infection and 1 developed a pneumothorax after LCNB. CONCLUSION: Image-guided LCNB is a reliable diagnostic alternative to surgical excision of suspicious nonpalpable breast abnormalities.


Assuntos
Biópsia por Agulha , Neoplasias da Mama/patologia , Adulto , Idoso , Biópsia por Agulha/instrumentação , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Ultrassonografia
4.
J Clin Ultrasound ; 27(2): 55-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9932248

RESUMO

PURPOSE: We describe the gray-scale and Doppler sonographic features of the corpus luteum during the first trimester of pregnancy. METHODS: Using transvaginal sonography, we prospectively evaluated the ovaries of 160 patients with spontaneous singleton intrauterine gestations between 5 and 8 weeks' menstrual age. Size, sonographic appearance, resistance index, and peak systolic velocity were recorded. RESULTS: The corpus luteum was identified in 157 (98%) of 160 patients. The mean diameter was 1.9 +/- 0.6 cm. The most common appearance was a round hypoechoic structure, found in 54 patients (34%). Other appearances included a cyst with a thick wall and anechoic center (43 patients, 27%), a cyst containing internal debris (36 patients, 23%), and a thin-walled simple cyst (24 patients, 15%). Corpus luteal blood flow was visualized with color Doppler imaging in 92% (145/157) of patients in whom the corpus luteum was found. Color Doppler imaging typically revealed a circumferential rim surrounding part or all of the corpus luteum. Low-resistance blood flow was seen with pulsed Doppler interrogation, with a mean resistance index of 0.49 +/- 0.08 and mean peak systolic velocity of 17 +/- 10 cm/second. CONCLUSIONS: The corpus luteum in early pregnancy is routinely identified with transvaginal sonography and has a wide range of sonographic appearances. Recognizing the various appearances of the corpus luteum is important to avoid confusing them with true ovarian abnormalities.


Assuntos
Corpo Lúteo/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Gravidez , Estudos Prospectivos
5.
Clin Imaging ; 21(4): 290-2, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9215479

RESUMO

Cystoendoscopic examination and standard radiological techniques occasionally fail to correctly establish that a pelvic mass is due to carcinoma arising within a urinary bladder diverticulum. MR imaging in oblique planes can facilitate the diagnosis in such cases by demonstrating the neck of the diverticulum. Also, T2-weighted images allow differentiation between tumor within a diverticulum and a necrotic extravesical mass.


Assuntos
Carcinoma de Células de Transição/diagnóstico , Divertículo/diagnóstico , Imageamento por Ressonância Magnética , Doenças da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Carcinoma de Células de Transição/complicações , Divertículo/complicações , Humanos , Masculino , Tomografia Computadorizada por Raios X , Bexiga Urinária/patologia , Doenças da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/complicações
6.
J Ultrasound Med ; 16(2): 95-9, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9166800

RESUMO

The purpose of this study was to assess the predictive value and sensitivity of discrepant ventricular size for fetal aortic coarctation. Postnatal follow-up data were obtained in 42 fetuses in whom ventricular size discrepancy (left ventricle smaller than right ventricle) was recognized on an obstetrical sonogram. Additionally, from postnatal records, we identified infants with coarctation who had had an obstetrical sonogram after 16 weeks. Fourteen of the 42 fetuses had coarctation or other aortic arch obstruction after birth (33% positive predictive value). Eight (62%) of 13 fetuses with ventricular discrepancy recognized before 34 weeks had coarctation, compared with six (21%) true positive cases among 29 recognized after 34 weeks (P = 0.01, Fisher's exact test). Of 21 infants with coarctation, ventricular discrepancy had been recognized by prenatal sonography in 13 (62% sensitivity). Ventricular discrepancy has moderate sensitivity and mediocre positive predictive value for coarctation. The limitations of this finding for diagnosing coarctation, particularly a higher false positive rate after 34 weeks, must be recognized, but it is still a useful sign to identify this potentially ductus-dependent lesion.


Assuntos
Coartação Aórtica/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Ventrículos do Coração/patologia , Ultrassonografia Pré-Natal , Antropometria , Feminino , Humanos , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Pediatr Radiol ; 26(5): 333-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8657462

RESUMO

OBJECTIVE: The goal of the study was to determine whether soft-copy images on high-resolution monitors (2.5 K x 2 K) are suitable for primary interpretation of images from pediatric and neonatal intensive care units. The hypotheses were that hard and soft images yield similar diagnostic information, and that both residents and faculty radiologists can use monitors effectively. Previous reports have produced conflicting results; the need for larger sample sizes has been emphasized. MATERIALS AND METHODS: One thousand one hundred and four images produced by computed radiography using the Kodak Ectascan Imagelink system were prospectively analyzed by two pediatric radiologists, one reading hard copy and the other soft copy of the same images. Bias was controlled by equal distribution of modalities between observers and by daily alternation of modality. Hard- and soft-copy observations of presence or absence of nine specific tubes and nine specific diagnostic findings were compared. Interobserver differences between pediatric radiologists and radiology residents were studied on additional images. The kappa statistic was used to evaluate the level of agreement for all observations. RESULTS: There was excellent agreement between hard and soft copy interpretation for each tube and diagnostic finding (kappa values 0.93-1.0) and excellent interobserver agreement between two pediatric radiologists (kappa values 0.84-1.0). The level of agreement between radiology residents and pediatric radiologist was excellent for the most objective findings. All results were statistically significant (p < 0.001). CONCLUSION: High resolution soft-copy images are suitable for primary interpretation in patients in pediatric and neonatal intensive care units.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Intensificação de Imagem Radiográfica , Sistemas de Informação em Radiologia , Criança , Terminais de Computador , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Variações Dependentes do Observador , Estudos Prospectivos , Radiografia Abdominal , Doenças Torácicas/diagnóstico por imagem , Ecrans Intensificadores para Raios X
8.
Radiology ; 197(3): 735-8, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7480747

RESUMO

PURPOSE: To evaluate the utility of stereotaxic core biopsy (SCB) in diagnosing recurrent carcinoma after breast-conserving therapy (BCT). MATERIALS AND METHODS: Of 316 patients evaluated with SCB, 17 (5%) had nonpalpable lesions in breasts previously treated with BCT. Surgical correlation was obtained in 14 patients. SCBs were performed with digital stereotaxic equipment, with patients prone. RESULTS: Carcinoma detected at SCB in 11 (79%) of 14 patients included infiltrating ductal carcinoma (IFDC) in five, ductal carcinoma in situ (DCIS) in five, and infiltrating lobular carcinoma (ILC) in one. Surgical histopathologic findings agreed with core biopsy findings in 10 of these patients. In one patient with two SCB-proved foci of IFDC, one IFDC was identified at mastectomy. In two (14%) patients, SCB revealed atypical ductal hyperplasia; however, DCIS was found at surgical biopsy. In one patient, the SCB finding of fat necrosis was confirmed at surgical biopsy. CONCLUSION: These data suggest that SCB may be useful in diagnosing recurrent carcinoma in the conservatively treated breast.


Assuntos
Biópsia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma/patologia , Carcinoma/cirurgia , Mastectomia Segmentar , Recidiva Local de Neoplasia/patologia , Técnicas Estereotáxicas , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Calcinose/patologia , Carcinoma/diagnóstico por imagem , Carcinoma in Situ/diagnóstico por imagem , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Terapia Combinada , Necrose Gordurosa/patologia , Feminino , Humanos , Hiperplasia , Mamografia , Mastectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Radiologia Intervencionista
9.
Nature ; 356(6366): 258-60, 1992 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-1552945

RESUMO

The need to develop a blood substitute is now urgent because of the increasing concern over blood-transmitted viral and bacterial pathogens. Cell-free haemoglobin solutions and human haemoglobin synthesized in Escherichia coli and Saccharomyces cerevisiae have been investigated as potential oxygen-carrying substitutes for red blood cells. But these haemoglobins cannot be used as a blood substitute because (1) the oxygen affinity in the absence of 2,3-bisphosphoglycerate is too high to allow unloading of enough oxygen in the tissues, and (2) they dissociate into alpha beta dimers that are cleared rapidly by renal filtration, which can result in long-term kidney damage. We have produced a human haemoglobin using an expression vector containing one gene encoding a mutant beta-globin with decreased oxygen affinity and one duplicated, tandemly fused alpha-globin gene. Fusion of the two alpha-globin subunits increases the half-life of this haemoglobin molecule in vivo by preventing its dissociation into alpha beta dimers and therefore also eliminates renal toxicity.


Assuntos
Substitutos Sanguíneos , Hemoglobinas/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Animais , Substitutos Sanguíneos/efeitos adversos , Cristalização , Escherichia coli/genética , Globinas/genética , Globinas/metabolismo , Meia-Vida , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Nefropatias/induzido quimicamente , Substâncias Macromoleculares , Estrutura Molecular , Mutação , Oxigênio/metabolismo , Ratos , Ratos Endogâmicos , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/metabolismo
10.
Biotechnology (N Y) ; 9(1): 57-61, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1367213

RESUMO

We have expressed human alpha and beta-globin cDNA clones from separate, synthetic galactose-regulated hybrid promoters contained on a single plasmid in Saccharomyces cerevisiae. Co-expression of the alpha and beta-globin chains in S. cerevisiae results in the assembly of these proteins into soluble tetrameric hemoglobin that accumulates to 3-5 percent of the total cell protein. Endogenously produced heme is incorporated into the tetramer and the protein produced is functionally and structurally indistinguishable from human Ao hemoglobin. This expression system has been used to produce both wild type hemoglobin and a low O2-affinity hemoglobin mutant that has oxygen binding and dissociation characteristics similar to human whole blood. The yeast expression system we describe may be suitable for the production of a recombinant hemoglobin based blood substitute as well as for detailed structure-activity studies of human hemoglobin.


Assuntos
Hemoglobinas/biossíntese , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Galactose/farmacologia , Regulação da Expressão Gênica , Globinas/biossíntese , Globinas/genética , Globinas/metabolismo , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Dados de Sequência Molecular , Mutação , Oxigênio/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética
11.
Proc Natl Acad Sci U S A ; 87(21): 8521-5, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2236062

RESUMO

Synthetic genes encoding the human alpha- and beta-globin polypeptides have been expressed from a single operon in Escherichia coli. The alpha- and beta-globin polypeptides associate into soluble tetramers, incorporate heme, and accumulate to greater than 5% of the total cellular protein. Purified recombinant hemoglobin has the correct stoichiometry of alpha- and beta-globin chains and contains a full complement of heme. Each globin chain also contains an additional methionine as an extension to the amino terminus. The recombinant hemoglobin has a C4 reversed-phase HPLC profile essentially identical to that of human hemoglobin A0 and comigrates with hemoglobin A0 on SDS/PAGE. The visible spectrum and oxygen affinity are similar to that of native human hemoglobin A0. The recombinant protein shows a reduction in Bohr and phosphate effects, which may be attributed to the presence of methionine at the amino termini of the alpha and beta chains. We have also expressed the alpha- and beta-globin genes separately and found that the expression of the alpha-globin gene alone results in a marked decrease in the accumulation of alpha-globin in the cell. Separate expression of the beta-globin gene results in high levels of insoluble beta-globin. These observations suggest that the presence of alpha- and beta-globin in the same cell stabilizes alpha-globin and aids the correct folding of beta-globin. This system provides a simple method for expressing large quantities of recombinant hemoglobin and allows facile manipulation of the genes encoding hemoglobin to produce functionally altered forms of this protein.


Assuntos
Escherichia coli/genética , Globinas/genética , Hemoglobinas/genética , Óperon , Sequência de Bases , Clonagem Molecular , Genes Sintéticos , Hemoglobinas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Cinética , Substâncias Macromoleculares , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/síntese química , Oxiemoglobinas/metabolismo , Ácido Fítico/farmacologia , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição
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