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91.
92.
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation. 相似文献
93.
Sequence determination of the capsid protein gene and flanking regions of tobacco etch virus: Evidence for synthesis and processing of a polyprotein in potyvirus genome expression 总被引:6,自引:2,他引:6 下载免费PDF全文
Allison RF Sorenson JC Kelly ME Armstrong FB Dougherty WG 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(12):3969-3972
The nucleotide sequence of the 3′-terminal portion of the tobacco etch virus (TEV) genome was determined. The 2324-nucleotide sequence represented approximately one-fourth of the TEV genome and included the capsid protein gene and flanking regions. An open reading frame of 2135 nucleotides and an untranslated region of 189 nucleotides adjacent to a polyadenylate tract were identified. The sequence began within an open reading frame, indicating that the initiation codon was upstream of the available sequence data. The sequence of the 20 NH2-terminal amino acids of the TEV capsid protein was established chemically. An identical amino acid sequence, predicted from the nucleotide sequence, was located, commencing at amino acid - 263. These data indicated that maturation of the capsid protein required a post-translational cleavage of a larger protein precursor, with a probable cleavage site between the amino acids glutamine and glycine. 相似文献
94.
Stephens RW; Golder JP; Fayle DR; Hume DA; Hapel AJ; Allan W; Fordham CJ; Doe WF 《Blood》1985,66(2):333-337
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone. 相似文献
95.
A. Michael Peters Helen Allison W. Yu. Ussov 《European journal of nuclear medicine and molecular imaging》1994,21(4):322-327
Individual kidney glomerular filtration rate (IKGFR) can be measured from the renogram from the rate of uptake of technetium-99m diethylene triamine penta-acetic acid (99mTc-DTPA). A blood sample is required to derive IKGFR in millilitres per minute, which is then usually normalised to body surface area. We describe a technique which does not require a blood sample, is already normalised for plasma volume and uses the robust Patlak plot for measuring renal uptake. The rate of kidney uptake, dR(t)ldt, at time = 0, as a fraction of the injected dose, is equal to the fraction of the plasma volume (PV) filtered per minute, i.e. IKGFR/PV. The gradient dR(0)/dt cannot be accurately measured directly but is equal to [ · LV(0)], where is the renal uptake constant (proportional to IKGFR) and LV is the count rate over a left ventricular ROI. LV(0) was obtained by extrapolation of LV(t), while a is the slope of the Patlak plot up to 3 min. GFR/PV (i.e. right plus left kidneys) in patients with normal renal function was about 0.04 min–1, as would be expected from normal values of GFR (120 ml/min) and plasma volume (3 l). GFR/PV correlated significantly with the ratio of GFR to extracellular fluid volume (ECV), measured from the terminal exponential of the plasma clearance curve (GFR/PV = 3.2.GFR/ECV + 5.3 ml/min/1 [r = 0.82,n = 82]). GFR/PV (r = 0.74) and GFR/ECV (r = 0.82) both correlated inversely and non-linearly with plasma creatinine in 43 studies where the measurement was made within 1 week of the99mTcDTPA study. They also correlated significantly with the plasma cyclosporin trough level in 14 patients with dermatomyositis on the 30 occasions when this measurement was made within 1 week of the renogram (r = –0.38,P < 0.05 for GFR/PV andr = –0.77,P < 0.001 for GFR/ECV). The ratio of GFR/PV to GFR/ECV is the ratio of extracellular fluid volume to plasma volume, and this was 4.0 (SD 0.99). We conclude that both GFR/PV and GFR/ECV can be easily measured with99mTc-DTPA and are physiologically valid expressions of GFR. Although GFR/PV and GFR/ECV correlate with each other, the question is raised as to which of the two fluid volumes is the most appropriate for normalising GFR.
Correspondence to: A.M. Peters 相似文献
96.
97.
98.
This study compared the acute stress disorder and post traumatic stress disorder PTSD symptom profiles in motor vehicle accident survivors who sustained a mild traumatic brain injury MTBI or no TBI. Consecutive adult patients who sustained a MTBI n=79 and no TBI n=92 were assessed for acute stress disorder within 1 month of their trauma and reassessed for PTSD MTBI: n=63; non TBI; n=72 6 months post trauma. Comparable rates of acute stress disorder and PTSD were reported in MTBI and non TBI patients. Intrusive memories and fear and helplessness in response to the trauma were reported less frequently by MTBI than non TBI patients at the acute phase. Six months post trauma fewer MTBI patients than non TBI reported fear and helplessness in response to the trauma. These findings suggest that, whereas impaired consciousness at the time of a trauma may reduce the frequency of traumatic memories in the initial month post trauma, MTBI does not result in a different profile of longer term PTSD. 相似文献
99.
Proteinuria and interstitial injury. 总被引:8,自引:3,他引:8
Allison A Eddy 《Nephrology, dialysis, transplantation》2004,19(2):277-281
100.
Peace D. Imani Amos Odiit Sangeeta R. Hingorani Noel S. Weiss Allison A. Eddy 《Pediatric nephrology (Berlin, Germany)》2013,28(11):2199-2206