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561.
To clarify normal values for cervical prevertebral soft-tissue measurements and evaluate when they are useful as a marker of cervical spine injury, the prevertebral soft-tissue measurements of 79 control and 57 acutely injured patients were retrospectively compared by two independent observers. The second, blinded, observer made a provisional diagnosis and indicated if increased soft-tissue measurements had assisted in making a diagnosis of injury. If measurements ≥7 mm at C2/3 and ≥21 mm at C6/7 were considered abnormal, a true positive rate of 53% and false positive rate of 5% were observed. The differences between the mean measurements in the control and injured groups were statistically significant (P<0.0001 at C2/3 and P<0.01 at C6). Soft-tissue measurement improved the diagnostic confidence of the blinded second reviewer in 17.5% of the injured group. Analysis of this subgroup revealed a 50% error rate in initial reporting. In all of these cases, the abnormal soft-tissues had been ignored prospectively. Routine measurement of the prevertebral soft tissues is a simple procedure that may provide an important clue to subtle cervical spine injury.  相似文献   
562.
The conversion of methionine to cyst(e)ine was determined in sheep infused with different amounts of methionine (0-5 g/d) into the duodenum by assaying the incorporation of 35S from intravenously-infused L-[35S]methionine into cyst(e)ine in wool, plasma albumin and the free plasma pool. The percentage of cystine-S in the plasma originating from methionine increased linearly from 4.5 to 18 with increasing supplemental methionine supply. The percentage of cysteine-S in albumin increased from 15 to 50; methionine supply increased to 3 g/d but then remained constant, indicating that the transsulphuration pathway of the liver was exceeded. The percentage of wool cysteine-S originating from methionine was high (approximately 70) at all methionine supplementation rates.  相似文献   
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566.
Testicular microlithiasis: imaging appearances and pathologic correlation   总被引:13,自引:0,他引:13  
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567.
Russin  LD 《Radiology》1986,159(1):115-116
Two women who had been sterilized by tubal ligation or cautery experienced recurrent pelvic pain several years later, and cystic adnexal masses were recognized in both patients. Both patients had bilateral hydrosalpinges with unilateral torsion and gangrene. These cases suggest there may be a predisposition to hydrosalpinx and tubal torsion following tubal ligation if the fimbriated end of the fallopian tube becomes occluded. Awareness of this potential complication may lead to increased recognition and earlier intervention in patients who have undergone tubal ligation.  相似文献   
568.
A monoclonal antibody to endothelial NOS (eNOS) was used to demonstrate the distribution and density of eNOS in the developing porcine lung. Lung tissue from large white pigs aged from less than 5 minutes to 3 months was immunostained and, using light microscopy, distribution of eNOS was assessed by a semiquantitative scoring system. At all ages eNOS was located on the endothelial cells of pulmonary and bronchial arteries and veins. Immunoreactivity for eNOS was greater in the larger, more proximal pulmonary arteries than at the periphery. In the lung of newborn pigs immunoreactivity for eNOS was present in arteries of all sizes but some showed no positive staining. At 2-3 days of age almost all arteries showed positive immunoreactivity. By 3 months of age the amount of eNOS had decreased and was less than that seen in the newborn. The highest level of eNOS was seen immediately after birth when the pulmonary arteries are dilating. eNOS may therefore play an important part in adaptation to extra-uterine life.  相似文献   
569.
Abstract We have studied effects of two partially purified human leukocyte (α) interferon (IFN) preparations (PIF-A and PIF-B) and a highly purified fibroblast (β) IFN on the functional activity of normal human neutrophils (PMNs). In vitro, PIF-B conferred a significant and dose-dependent enhancement of chemiluminescence (CL) induced both by phagocytosis and a soluble stimulus, f-Met-Leu-Phe, and decreased killing of Staph aureus. In contrast, PIF-A caused only a slight inhibition of bactericidal activity and had no effects on CL. β-IFN had no effects on either bactericidal activity or CL. Migration under agarose was decreased with all of the IFN but phagocytosis and release of enzymes was not affected. PMNs from seven patients treated with PIF-A for multiple myeloma exhibited increased CL responses but no other PMN functions were affected. The findings that human IFN preparations affect PMN functions indicate that high-dose IFN therapy of immunocompromised patients should be carefully evaluated for the possibility of increased infectious complications.  相似文献   
570.
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