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991.
We have synthesized pulmonary surfactant apoprotein SP-B peptides by solid-phase chemistry and demonstrated their ability to enhance the surface-active properties of synthetic lipid mixtures. The synthetic peptides were reactive with antiserum generated against the native bovine surfactant peptide. Both peptides conferred surfactant-like properties to synthetic lipid mixtures as assessed by a Wilhelmy balance and pulsating bubble surfactometer. Likewise, mixtures of synthetic SP-B peptides and lipid restored compliance of isolated surfactant-deficient rat lungs. This work demonstrates the utility of SP-B as a functional component of pulmonary surfactant mixtures for treatment of respiratory distress syndrome or other disorders characterized by surfactant deficiency.  相似文献   
992.
A longitudinal study of platelet behaviour (platelet aggregation and release reaction) in whole blood and of serum thromboxane B2 production was performed before, during and after normal pregnancy. The response of platelets to arachidonic acid and to adrenaline was significantly increased in the third trimester. Six weeks after delivery, values were still modestly increased but return to non-pregnant values was complete by 12 weeks. Serum thromboxane B2 production was unchanged throughout pregnancy and the puerperium.  相似文献   
993.
The scars of newborn intensive care   总被引:2,自引:0,他引:2  
Many techniques used in neonatal intensive care are invasive and the risk of producing skin damage is high. To investigate this, 100 consecutive survivors of neonatal intensive care (gestation 26-42 weeks, median 32) were examined in detail by a single observer at 16-29 months of age, and the scar severity, site and likely cause noted. Scarring was present in all infants although it was usually trivial. The total number of scars was inversely related to gestational age and directly related to the duration of intensive care. Eleven children had cosmetically or functionally significant lesions caused by chest drain insertion, extravasation of intravenous fluid or skin stripping by adhesive tape. To reduce the frequency and severity of skin damage, neonatal staff need to be aware that many routine procedures may lead to long term scarring. In particular, more careful wound closure after chest drain removal is needed.  相似文献   
994.
Vacuum drainage of groin wounds after vascular surgery: a controlled trial   总被引:1,自引:0,他引:1  
A pilot study of 100 consecutive groin wounds after vascular surgery demonstrated lymph leaks in 12 per cent. Lymph leak was significantly associated with wound infection and with prolongation of in-patient stay. A controlled trial was therefore instituted to assess the influence of vacuum drainage in groin wound healing. One hundred and twenty-seven wounds were randomized to drainage (n = 65) or no drainage (n = 62) and the wounds were examined 'blind' by independent observers. No difference in the incidence of lymph leakage or wound infection was noted between the two groups. The routine use of suction drainage for groin wounds in vascular surgery is unnecessary.  相似文献   
995.
996.
A three-pool model was used to improve white-matter T2 relaxometry in low signal-to-noise (SNR) data. To verify the model very high SNR T2 relaxometry experiments were performed on myelinated tissue samples and three-pool fractions were consistently found. Relaxation curves based on the in vitro results were simulated with multiple SNRs and fit using the three-pool model and three less constraining nonnegative least squares-based methods. All methods performed well with noiseless data. At lower SNR values the three-pool model was superior, primarily due to the fact that the other methods often could not unambiguously calculate pool fractions.  相似文献   
997.
Therapeutic trials in Huntington's disease (HD) are challenging as clinical progression is slow and variable and reliable biomarkers are lacking. We used magnetic resonance imaging and the brain boundary shift integral to quantify whole‐brain atrophy rates over 1 year in early and premanifest HD subjects, and controls. Early HD subjects had statistically significantly (P = 0.007) increased (threefold higher) rates of whole‐brain atrophy compared with controls. Higher atrophy rates were associated with longer CAG repeat length. MRI‐based measures of whole‐brain atrophy may have potential as a measure of progression in HD. © 2009 Movement Disorder Society  相似文献   
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A sensitive enzyme linked immunosorbent assay (ELISA) was developed to evaluate the potential of herpes simplex virus (HSV) specific antibodies in the diagnosis of herpetic eye infection. The presence of HSV specific secretory IgA (sIgA) in tears was found to be diagnostic of infection. However, serum and tear HSV specific IgG and IgA were not considered reliable indicators of active infection.  相似文献   
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