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91.
Chou  AC; Broun  GO Jr; Fitch  CD 《Blood》1978,52(1):187-195
Rabbits fed a vitamin E-deficient diet developed severe muscular dystrophy in 3-4 wk, but they did not become anemic. Nevertheless, reticulocyte counts increased in deficient rabbits (3.2%) compared to control rabbits (0.9%), and erythroid hyperplasia was evident in the bone marrow. Comparing deficient rabbits to controls, the plasma iron concentration was lower (134.4 versus 206.6 microgram/dl); the TIBC was higher (335.9 versus 228.3 microgram/dl); the whole blood protoporphyrin concentration was higher (131.6 versus 81.7 microgram/dl); and the total iron content was lower in spleen (71 versus 153 microgram), higher in skeletal muscle (4956 versus 3054 microgram), and unchanged in bone marrow, liver, and heart. Studies of iron absorption and excretion using 59Fe showed no abnormalities in deficient rabbits. There were abnormalities of ferrokinetics, however. The half-time of disappearance of 59Fe was shorter (100.6 versus 169.4 min), the plasma iron turnover was greater (1.25 versus 0.95 mg/dl blood/day), and the reappearance of 59Fe in circulating erythrocytes at day 9 was greater (77.2% versus 57.2%) in deficient rabbits. Anemia induced by phlebotomy accentuated the abnormal iron metabolism of deficient rabbits, and the animals were unable to correct the anemia. These findings show that vitamin E deficiency in rabbits causes abnormal erythropoiesis associated with abnormal iron metabolism and sequestration of iron in skeletal muscle.  相似文献   
92.
Hemophilia A: carrier detection and prenatal diagnosis by DNA analysis   总被引:2,自引:0,他引:2  
In this study, we used DNA polymorphisms for carrier detection and prenatal diagnosis of hemophilia A in a large group of Italian families. The restriction fragment length polymorphisms (RFLPs) investigated were the intragenic polymorphic Bc/I site within the factor VIII gene; the extragenic multiallelic Taq I system at the St14 locus; and the extragenic Bg/II site at the DX13 locus. The factor VIII probe was informative in 30%, St14 in 82%, and DX13 in 60% of obligate carriers. The combination of factor VIII-Bc/I and St14-Taq I showed that 91% of obligate carriers were heterozygotes for one or both; with all three probes, only 4% of obligate carriers were noninformative. In families clearly segregating for hemophilia A, RFLP analysis allowed us to define the carrier status for the hemophilia A gene in all 27 women tested. RFLP analysis allowed us to exclude the carrier status in 39 of 45 female relatives of sporadic patients. The combination of RFLP analysis and biological assay of factor VIII allowed us to identify a de novo mutation in the maternal grandfather in 7 of 12 of the families with sporadic cases, for which members of three generations were available for study. Nine of 10 couples requesting prenatal diagnosis provided informative RFLP DNA pattern. Carrier status was excluded in two women, two fetuses were shown to be female, and prenatal diagnosis was carried out in five pregnancies by DNA analysis. Prenatal testing was successful in three instances and failed in two because a sufficient amount of chorionic villous DNA was not obtained for the analysis.  相似文献   
93.
Martens  AC; Schultz  FW; Hagenbeek  A 《Blood》1987,70(4):1073-1078
In a rat model (BNML) for human acute myelocytic leukemia the distribution of leukemic cells in bone marrow samples from various sites was investigated, using monoclonal antibodies (MoAbs) and flow cytometry. Rats were studied before chemotherapy as well as thereafter, ie, in the "minimal residual disease" (MRD) phase. Bone marrow from different types of bones was analyzed from each animal. Before treatment, the ratio of the measured extreme values (ie, highest/lowest value) for leukemic cell frequencies in bones from individual rats ranged from 3.7 to 11.7. During the MRD phase the ratios of the extremes ranged from a factor of 36 to more than 13,000 from one rat to another. The variability between bones of comparable size was estimated by studying the ribs from each individual animal. Within individuals the extremes differed by a factor of 1.2 to 4.0 before chemotherapy and from 2.4 to greater than 320 after chemotherapy. The variability within the marrow cavity of a single bone was determined by analyzing multiple samples from femoral bones cut into slices. The leukemic cell frequency appeared to vary considerably, ie, before treatment from 1.7 to 7.3 and during MRD from 4 to 28,000. The presented data may contribute to understanding the sometimes conflicting observations in leukemic patients. Improvement of methods for detecting MRD will not automatically lead to a more accurate estimation of the total tumor burden. The reliability of diagnoses based on the analysis of single bone marrow aspirates appears to be highly questionable.  相似文献   
94.
BACKGROUND & AIMS: Intestinal transplantation is a developing therapeutic option for patients with irreversible intestinal failure or short bowel syndrome. The aim of this study was to delineate the histopathology of human intestinal allografts and to define the features of intestinal rejection. METHODS: The histological features of 3015 endoscopic biopsy specimens and 23 allograft specimens from 62 intestinal recipients were analyzed retrospectively and correlated with clinical findings. RESULTS: Acute allograft rejection was characterized by a varying combination of crypt injury, mucosal infiltration primarily by mononuclear cells (including blastic lymphocytes), and increased crypt cell apoptosis (more than 2 per 10 crypts). It represented a patchy, often ileal-centered process that could progress to mucosal ulceration; later episodes (more than 100 days posttransplant) tended to show lesser cellular infiltration and greater apoptosis than earlier episodes. Correlation with clinical rejection was good (false-positive rate of 9%; false-negative rate of 26%). Two resected specimens showed obliterative arteriopathy indicative of chronic rejection. In other specimens, preservation injury, cytomegalovirus infection, post-transplant lymphoproliferative disorder, and nonspecific features of active or past mucosal injury could be recognized. CONCLUSIONS: Mucosal biopsy specimens are a useful means of monitoring intestinal allografts. Based on features validated by clinical correlation, acute rejection can be identified reliably and can be differentiated from the other pathological processes affecting the intestinal allograft. (Gastroenterology 1996 Jun;110(6):1820-34)  相似文献   
95.

INTRODUCTION

Vernix caseosa peritonitis (VCP) is a rare and poorly recognised condition resulting from a sustained foreign body reaction to the vernix caseosa of the baby. This case-based review aims to highlight its importance for any medical team managing patients with peritonitis who have undergone a recent Caesarean section.

CASE REPORT

A 31-year-old woman presented 5 weeks after a Caesarean section with symptoms and signs of peritonitis.

CONCLUSIONS

Laparotomy and peritoneal lavage is the mainstay of treatment for VCP. Knowledge of the condition may stop inadvertent resection of normal intra-abdominal organs. Greater awareness of VCP is required to ensure earlier recognition as patients can recover well following timely operative intervention.  相似文献   
96.
97.
Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment.   相似文献   
98.
99.
100.
CORRELATIONBETWEENTHENUMBEROFMITOTICFIGURESANDTHEPERCENTAGEOFKi67-POSITIVECELLS INNON-HODGKIN’SLYMPHOMASHuangGaosheng;(黄高升)Fe...  相似文献   
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