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991.
992.
J. A. Spencer J. Ward J. A. Guthrie P. J. Guillou P. J. A. Robinson 《European radiology》1998,8(1):23-29
The aim of our work was to investigate the use of a dynamic contrast-enhanced MR (DCEMR) technique for staging apparently
localised pancreatic cancer, and to determine the patterns of tumour and vascular enhancement with this technique. Thirty-five
consecutive patients were examined. The MR findings were correlated with surgical findings in 13 patients and with clinical
outcome in 22 patients. Breath-hold gradient-echo fast low angle shot (TR = 100, TE = 4, flip angle 80 °) acquisitions were
obtained at 10 and 40 s (right anterior coronal oblique plane) and at 90 s (axial plane) following intravenous gadolinium.
Mean contrast-to-noise ratio was higher on the first than the second acquisition (p < 0.001) and higher on the second acquisition than the third (p < 0.005). Tumour conspicuity was greatest and arterial anatomy was best demonstrated on the first acquisition and the portal
venous anatomy on the second. Small tumours were isointense by the third acquisition. Maximal intensity projections were helpful.
The MR findings correctly predicted the surgical findings in 11 of 13 cases (85 %) and the clinical course in the other 22
patients. The DCEMR imaging technique is valuable in the staging of patients with pancreatic cancer. Capillary and portal
venous phase images are both required for complete local staging.
Received 5 November 1996; Revision received 24 March 1997; Accepted 21 April 1997 相似文献
993.
994.
Experiences of the first 493 unrelated marrow donors in the National Marrow Donor Program 总被引:5,自引:2,他引:3
Stroncek DF; Holland PV; Bartch G; Bixby T; Simmons RG; Antin JH; Anderson KC; Ash RC; Bolwell BJ; Hansen JA 《Blood》1993,81(7):1940-1946
More than 410,000 people participated in the National Marrow Donor Program (NMDP) as of October 1, 1991, and more than 850 volunteers had donated marrow. While the incidence of serious morbidity as a result of bone marrow donation is rare, the incidence of lesser complications and the long-term consequences of marrow donation are not known. To determine the incidence of donor complications and measure the recovery time of volunteer, unrelated marrow donors, we analyzed the results of surveys of the first 493 persons who donated marrow through the NMDP. The marrows were collected at 42 centers. The median age of the donors was 37.9 years (range 19.1 to 55.6 years). The median volume of marrow collected was 1,050 mL (range 180 to 2,983 mL). Autologous red blood cells were transfused to 89.8% (439) of donors but only 0.6% (3) of donors received allogeneic blood. Acute complications related to the collection procedure occurred in 5.9% of donors; but a serious complication, apnea during anesthesia, occurred in only one donor. When donors were questioned approximately 2 days following discharge from their hospitalization, most donors described symptoms related to the collection; 74.8% experienced tiredness, 67.8% experienced pain at the marrow collection site, and 51.6% of the donors experienced low back pain. Donors were surveyed repeatedly until they felt that they had recovered completely. Mean recovery time was 15.8 days; however, 42 (10%) donors felt that it took them > or = 30 days to recover fully. The duration of the marrow collection procedure and duration of anesthesia both positively correlated with donor pain and/or fatigue following the collection; but the duration of the collection procedure had the highest correlation with post-collection pain and fatigue. The volume of marrow collected per unit of donor weight was more weakly correlated with donor pain and/or fatigue than the anesthesia and collection times. When multivariate analysis was used to analyze the correlation between donor recovery time and these variables, only the duration of the collection was found to correlate significantly with donor recovery time (P = .001). This analysis demonstrates that marrow donation is well tolerated with few complications. To decrease further the incidence of donor discomfort and recovery time following donation, the duration of the collection procedure, and probably the duration of anesthesia, and the volume of marrow collected, should be kept to a minimum. 相似文献
995.
Frequency and patterns of abnormality detected by iodine-123 amine emission CT after cerebral infarction 总被引:2,自引:0,他引:2
Single photon emission computed tomography (SPECT) was performed in 31 patients with cerebral infarction and 13 who had had transient ischemic attacks, using iodine-123-labeled N,N,N'-trimethyl-N'-(2-hydroxyl-3-methyl-5-iodobenzyl)-1,3-propanediamin e (I-123-HIPDM) as the radiopharmaceutical. SPECT scans were compared with computed tomographic (CT) scans. SPECT was as sensitive as CT in detecting cerebral infarction (94% vs. 84%). The abnormalities were larger on the SPECT scans than on the CT scans in 19 cases, equal in seven, and smaller in five (SPECT abnormalities greater than or equal to CT abnormalities in 86% of cases). Fifteen of 30 patients with hemispheric infarction had decreased perfusion (decreased uptake of I-123-HIPDM) to the cerebellar hemisphere contralateral to the cerebral hemisphere involved by the infarction (crossed cerebellar diaschisis). Nine of these 15 patients had major motor deficits, while only one of the 15 without crossed cerebellar diaschisis had a major motor deficit. 相似文献
996.
997.
A founder mutation in the gamma-sarcoglycan gene of gypsies possibly predating their migration out of India 总被引:4,自引:2,他引:2
Piccolo F; Jeanpierre M; Leturcq F; Dode C; Azibi K; Toutain A; Merlini L; Jarre L; Navarro C; Krishnamoorthy R; Tome FM; Urtizberea JA; Beckmann JS; Campbell KP; Kaplan JC 《Human molecular genetics》1996,5(12):2019-2022
We investigated the molecular basis of a severe form of early onset
autosomal recessive muscular dystrophy with sarcoglycan (SG) deficiency in
seven large Gypsy families living in different parts of Western Europe and
apparently not closely related. They were linked to the LGMD2C locus
(13q12) suggesting a primary defect in the gamma-SG gene coding for the 35
kDa dystrophin-associated glycoprotein. All of the 18 investigated patients
were homozygous for the same G-->A transition in codon 283 producing the
replacement of a conserved cysteine of the extra-cellular domain of the
protein by a tyrosine. All affected chromosomes in homozygous and
heterozygous relatives carried the same allele 5 of the intragenic marker
D13S232. Flanking markers were studied to delineate a common ancestral
haplotype, the size of which was used to compute the date of the founding
mutation. We found evidence that the mutation occurred between 60 and 200
generations ago, therefore possibly predating the commonly accepted date of
migration of the Gypsy ancestors out of India.
相似文献
998.
G M Guthrie H A Guthrie T L Fernandez N O Estrera 《Social science & medicine (1982)》1985,20(7):713-717
An experiment was performed on the maternity wards of three public hospitals in Cebu City, Philippines to determine whether the distribution of free samples of infant formula reduced the likelihood that mothers would breast feed or caused mothers to terminate nursing early. Samples were given or withheld alternately for 2 week intervals to mothers as they left maternity wards. They were followed for 8 months in the first experiment (N = 273) and for 2 months in a replication (N = 284). We found that there were no statistically significant differences between those who received samples and those who did not in initiation or maintenance of breast feeding. Mothers in both groups frequently turned to mixed schedules, but these varied from day to day depending on money to buy other forms of milk, or on the mother's health, or her plan to be away from the baby for one or more feeding periods. After the baby reached an age of 2-3 months, mothers, with few exceptions, used diluted sweetened condensed milk as a supplement and/or substitute for their own milk. It was found that, while mothers recognize the nutritional, economic and health benefits of breast feeding, they may terminate early on the basis of folk beliefs. Receiving formula samples, however, had no measured effect on their breast feeding practices. 相似文献
999.
Nontuberculous mycobacterial infection in AIDS: clinical, pathologic, and radiographic features 总被引:5,自引:0,他引:5
The medical records, radiographs, and pathologic specimens of ten patients with the diagnoses of nontuberculous mycobacterial infection and acquired immunodeficiency syndrome (AIDS) were examined. The radiographic findings of alveolar or nodular infiltrates and adenopathy were relatively nonspecific but in most cases led to bronchoscopic study or open-lung biopsy, which established the diagnosis. Bronchoscopic washings or sputum cultures, which frequently provided the first confirmation of infection, were always followed by positive blood or tissue cultures. In contrast to nontuberculous infection in immunocompetent hosts, disseminated infection was common, with evidence of extrapulmonary involvement in nine patients. On the basis of these findings, we recommend that any AIDS patient with sputum or bronchoscopic washings demonstrating nontuberculous mycobacterial organisms be tentatively classified as having disseminated infection while being evaluated with blood, bone-marrow, stool, and urine cultures, even if the chest radiograph shows no disease. 相似文献
1000.
JA Low AB Froese RS Galbraith JT Smith EE Sauerbrei EJ Derrick 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(5):433-437
Ninety-eight newborn infants, less than 34 weeks at birth, were studied to examine the relationship between newborn hypotension and hypoxemia and brain damage. Heart rate, blood pressure and oxygen tension were recorded continuously during the 96 h following delivery. Outcome measures included neuropathology in children who died, and motor and cognitive development at one year corrected age in children who survived. There were 22 children with a minor and 27 with a major abnormal outcome. There was a relationship between newborn hypotension, newborn hypoxemia and low birth weight, and a major abnormal outcome. The probability of a major abnormal outcome increased from 8% in newborns with no hypotension or hypoxemia, to 53% in children with both hypotension and hypoxemia. These findings support the contention that combinations of sustained newborn hypotension and hypoxemia are important factors in the development of brain damage, accounting for a major abnormal outcome. 相似文献