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141.
Seibert JJ; McCowan TC; Chadduck WM; Adametz JR; Glasier CM; Williamson SL; Taylor BJ; Leithiser RE Jr; McConnell JR; Stansell CA 《Radiology》1989,171(1):155-159
This study was conducted to determine if the resistive index (RI) could be used for the examination and follow-up of neonates with increased intracranial pressure. First, in a laboratory model with four mongrel dogs, RI was found to correlate linearly with cerebral perfusion pressure. Second, RI was studied in 57 healthy neonates and 285 neonates with abnormal clinical or head ultrasound findings. Average RI for healthy newborns was 75 +/- 10 and was inversely related to gestational age. RI in newborns with abnormal findings was uniformly elevated, but these values varied considerably and were not statistically different from normal values. Third, the RI was found to decrease significantly after patent ductus arteriosus ligation, tapping of subdural effusions, ventricular tapping (later cerebrospinal fluid shunting led to a further drop in RI), and ventriculoperitoneal shunting. Elevated RI indicates possible intra- or extracranial abnormality affecting cerebral blood flow. Doppler RI is valuable in following up neonates with abnormal or unstable conditions and in assessing the effectiveness of therapies to improve cerebral perfusion. 相似文献
142.
Recurrent miscarriage: principles of management 总被引:11,自引:7,他引:4
Recurrent miscarriage is a heterogeneous condition which has many possible
underlying causes. Ideally, couples with the problem should be managed in a
dedicated miscarriage clinic, with thorough investigations according to a
protocol, with structured history and investigation sheets. Counselling is
an important feature and may be provided by a specially trained counsellor,
or specialized nurse appropriately trained in counselling. Counselling
should include an explanation of the possible underlying causes of the
condition, and of the prognosis of each of the conditions. There is no
definite cause of miscarriage in approximately half of the patients. No
treatment is needed in this group, apart from reassurance and tender loving
care. Treatment of unproven value, for example progesterone support in
early pregnancy, should not be offered. Treatment offered empirically or as
part of a research project should have a sound scientific and statistical
basis, and should include careful counselling with informed consent of the
patient. There are many controversial issues in the management of recurrent
miscarriage; consequently, there is a need for locally agreed guidelines
for management. Women who conceive again should be offered regular
monitoring, including serial ultrasonography in the first trimester of
pregnancy. An active audit programme to review regularly the various
outcome measures set against defined targets should be established in the
clinic.
相似文献
143.
Cell surface aminopeptidases N (APN) and A (APA) have been characterized on cultured human glomerular epithelial cells and a SV40-transformed cell line derived from them. APN had a wide substrate specificity whereas APA only attacked peptides with an acidic N terminal amino acid. Both enzymes also differed by their sensitivity to divalent cations and to aminopeptidase inhibitors. Phorbolmyristate acetate (PMA) stimulated APN but not APA expression after a lag time of 12 hours. An increase of twice the basal value was observed with 10 ng.ml-1 PMA. This effect was confirmed by immunofluorescence staining using a specific anti-APN monoclonal antibody. Both ecto- and total enzyme activities were stimulated by PMA. The effect of PMA was suppressed by H7, a PKC inhibitor, and cycloheximide, an inhibitor of protein synthesis. Thrombin (1 to 2.5 U.ml-1) and interferon (IFN)-gamma (100 U.ml-1) also stimulated APN activity, the latter after longer exposure of the cells. APA activity was increased by 8-bromo-cAMP and two cAMP-stimulating agents, forskolin and isobutylmethylxanthine (IBMX). A twofold increase above basal value was obtained with 100 microM forskolin after 72 hours of treatment. cAMP-stimulated APA activity was suppressed by cycloheximide. Dexamethasone also stimulated APA activity. The effects of forskolin and dexamethasone were additive. These results demonstrate that APN and APA in glomerular epithelial cells are under different regulations: mitogens and IFN-gamma for APN, cAMP and glucocorticoids for APA. This selective expression may imply possible functional consequences in glomerular diseases. 相似文献
144.
145.
SUMMARY A case of Münchausen's syndrome with AIDS illustrates the need for a high index of caution when dealing with individuals whose histories are inconsistent and suspicious, particularly when they have moved area. 相似文献
146.
正相-反相两步高效液相色谱法制备毫克量级维生素D3异构体 总被引:2,自引:0,他引:2
利用正相半制备柱和反相分析柱的两步高效液相色谱法,在实验室规模制备了毫克是级维生素D3的三个重要异构体——维生素D3前体、光甾醇3和速甾醇3·维生素D3原体,7-去氢胆固醇的光照是在一个装有UVB荧光灯的光治疗室中进行。采用紫外分光光度法和高效液相色谱法对制得的三个异构体进行了定性定量分析。在这三个异构体检测极限下,除了维生素D3前体中有不超过0.25%的维生素D3杂质外,三个产品中均没有发现任何除它本身之外的其他异构体杂质。 相似文献
147.
SUMMARY The serendipitous presentation of a rectoperineal fistula in a 34-year-old nulliparous woman is described. This surgically correctable cause of an anogenital discharge posed a risk (if unrecognised) of producing a rectovaginal fistula at the time of vaginal delivery. 相似文献
148.
149.
150.
Steckley RA; Kronenberg MW; Born ML; Rhea TC; Bateman JE; Rollo FD; Friesinger GC 《Radiology》1982,142(1):179-185
Regional wall motion (RWM) abnormalities are sensitive indicators of left ventricular (LV) dysfunction, but quantitation of RWM with gated radionuclide ventriculography (RVG) has been limited, particularly in the left anterior oblique (LAO) projection. Regional LV performance was studied in 18 patients undergoing LAO RVG immediately prior to contrast ventriculography (CVG). Wall motion was analyzed by semiautomated and visual methods using several coordinate systems. For semiautomated methods, RVG and CVG wall motion were closely related in the two 90 degrees polar sectors at the apex and posterior wall (r = .85) and in the five 45 degrees polar sectors from midseptum through posterior wall (r = .82). The basal sectors on RVG had weak relationship to CVG, due to adjacent vascular structures. Semiautomated and visual grades for polar sectors on both CVG and RVG were closely related (r = .88- .94). Measured regional wall motion on LAO RVG compared favorably with near-simultaneous CVG in nonoverlapping portions of the LV and allowed objective quantitation of regional LV performance. 相似文献