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1.
Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
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An EMG and nerve-conduction-study protocol has been developed and used in all patients with brachial plexus lesions since 1985. The findings of EMG and nerve-conduction studies in obstetric brachial palsy (OBP) mostly suggest a falsely optimistic prognosis. To analyse this, all subjects were selected with complete avulsion of both roots C5 and C6 and/or complete rupture of the upper trunk verified during operation from a group of 162 infants with OBP (aged 4 to 14 months) and a group of 184 child and adult patients (aged 6 to 74 years) with a traumatic brachial plexus lesion. Fourteen infants, approximately 4 months old, with OBP, and 19 adults (aged 16 to 30 years) met the selection criteria. The infants from the group with OBP had at 4 months a nearly normal recruitment pattern of motor units in the biceps brachii and deltoid muscles, with little or no denervation. However, in the older group with traumatic brachial palsy, the same lesion caused complete denervation of both muscles. From the group with OBP, a third group (N=3) with the same lesion plus an additional lesion of C7 or a rupture of the middle trunk was selected. This additional lesion resulted in nearly complete denervation of both muscles. This means that C7 largely contributes to the innervation of both muscles at the time of birth, but this innervation is lost during later life in normally developing individuals (apoptosis). A central mechanism might be responsible for the clinical palsy and later spontaneous improvement which is always found in the infants with OBP.  相似文献   
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Aim: To describe cardiorespiratory fitness and body mass index (BMI) values in a representative population of 9-year-old Norwegian children in two rural communities and compare present values with previous findings.
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult.  相似文献   
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Morton  JD; Harrison  LB; Peschel  RE 《Radiology》1986,159(1):249-252
Of 179 patients with stage B or C adenocarcinoma of the prostate, 106 underwent iodine-125 seed-implant therapy (I-125 SI) and 73 received external-beam radiation therapy (EB). A retrospective analysis determined disease-free survival rate, local tumor control, and complication rate for each treatment group. The 5-year disease-free survival rates for SI-treated patients were 75% for stage B and 30% for stage C groups. Corresponding rates for EB-treated patients were 75% and 40%, respectively. The rate of local tumor control for stage B patients was 85% for SI-treated and 88% for EB-treated patients. The corresponding rates for stage C tumors were 75% for SI-treated and 92% for EB-treated patients. The rate of long-term complications in each group was approximately 10%. For stage B cancer of the prostate, I-125 SI treatment is an acceptable alternative to EB therapy; our data are inconclusive regarding stage C treatment, but EB therapy is preferred.  相似文献   
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The 13th edition of the standards of the American Association of Blood Banks specified storage at 1 to 6 degrees C for cryoprecipitated anti-hemophilic factor (Cryo) administered up to 6 hours after thawing if the Cryo is used for factor VIII (FVIII) content (Standard J4.210). Previous editions specified room-temperature (RT) storage for up to 6 hours. Currently, the temperature specification has been deleted. There are few data addressing the optimal storage temperature and maximum storage time for FVIII and fibrinogen in thawed Cryo. Thirty bags of Cryo were assayed for FVIII and fibrinogen. Each bag was divided into two aliquots; one was stored at RT and the other at 1 to 6 degrees C. Assays were performed immediately after thawing (Base) and 6 and 24 hours after thawing, respectively. All samples were filtered through 200-mu blood component infusion sets before assay. Three hundred analyses were performed, 150 each for FVIII and fibrinogen by conventional clotting technique. Data were analyzed by using a paired t test. Cryo stored at 1 to 6 degrees C for 6 and 24 hours showed an FVIII loss of 35 percent (p less than 0.0001) and 63 percent (p less than 0.0001), respectively. Cryo stored at RT for 6 and 24 hours had an FVIII loss of 8 percent (p greater than 0.05) and 20 percent (p less than 0.0001). Cryo stored at 1 to 6 degrees C for 6 and 24 hours had a fibrinogen loss of 20 percent (p less than 0.0001) and 43 percent (p less than 0.0001). Cryo stored at RT for 6 hours had no fibrinogen loss and a 2 percent loss at 24 hours (p greater than 0.05). These preliminary data show a significant loss of FVIII and fibrinogen activity in Cryo stored at 1 to 6 degrees C and filtered before assay. The FVIII and fibrinogen activity at RT is clearly maintained up to 6 hours after thawing.  相似文献   
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A near-fatal reaction during granulocyte transfusion of a neonate   总被引:1,自引:0,他引:1  
Although reactions to granulocyte transfusions in neonates are rarely reported, we observed a near-fatal pulmonary reaction, presumably due to white cell antibodies, in a neonate with Rh hemolytic disease. The hemolytic disease was being treated with exchange transfusions, and at 2 days after the infant's birth, bacterial sepsis was suspected and granulocyte transfusions were begun. The first granulocyte transfusion (Day 3) was uneventful. Five minutes after the beginning of the second granulocyte transfusion (Day 4), severe respiratory distress, hypotension, bradycardia, cyanosis, and acidosis suddenly occurred. The infant's serum obtained after the reaction contained granulocytotoxic and B-lymphocytotoxic antibodies that reacted with leukocytes from the second granulocyte donor. Antibodies could not be detected either in the initial infant serum or in maternal serum. However, an antileukocyte antibody was present in the serum of a parous woman donor. We used plasma from this woman to prepare reconstituted whole blood for the exchange transfusion that we performed immediately preceding the second granulocyte transfusion. Despite the sequence of events, an irrefutable cause-and-effect mechanism could not be established because the properties of the donor and neonatal antibodies were similar, but not identical. However, this catastrophic event emphasizes both the potential for adverse effects of granulocyte transfusions in neonates and the need for caution when transfusing blood from parous women.  相似文献   
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