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1.
A C Srivastava A J Pinching M W Adler R Robertson R Higgs 《BMJ (Clinical research ed.)》1987,294(6570):495-496
Dr A C Srivastava has written to us to describe a case that raises the suggestion that people infected with the human immuno-deficiency virus (HIV) should carry identity cards. We asked two physicians, a general practitioner working with patients with the acquired immune deficiency syndrome (AIDS), and a general practitioner with a special interest in medical ethics to respond to the broad issues raised by Dr Srivastava''s letter. 相似文献
2.
Unusual features of CpG-rich (HTF) islands in the human alpha globin complex: association with non-functional pseudogenes and presence within the 3'' portion of the zeta gene. 总被引:10,自引:1,他引:9 下载免费PDF全文
We have characterised a cluster of CpG rich (HTF) islands in the alpha-globin complex and report here two unusual features: The human embryonic zeta 2-globin gene is associated with an HTF island within its 3' portion rather than at the 5' end. Furthermore at least two non-functional pseudogenes within the cluster (psi zeta 1 and psi alpha 2) are associated with CpG rich islands. 相似文献
3.
Rossi A.; Gottfried S. B.; Higgs B. D.; Zocchi L.; Grassino A.; Milic-Emili J. 《Journal of applied physiology》1985,58(6):1849-1858
In 11 mechanically ventilated patients, respiratory mechanics were measured 1) during constant flow inflation and 2) following end-inflation airway occlusion, as proposed in model analysis (J. Appl. Physiol. 58: 1840-1848, 1985. During the latter part of inflation, the relationship between driving pressure and lung volume change was linear, allowing determination of static respiratory elastance (Ers) and resistance (RT). The latter represents in each patient the maximum resistance value that can obtain with the prevailing time constant inhomogeneity. Following occlusion, Ers and RT were also obtained along with RT (min) which represents a minimum, i.e., resistance value that would obtain in the absence of time constant inhomogeneity. A discrepancy between inflation and occlusion Ers and RT was found only in the three patients without positive end-expiratory pressure, and could be attributed to recruitment of lung units during inflation. In all instances Ers and RT were higher than normal. RT(min) was lower in all patients than the corresponding values of RT, indicating that resistance was frequency dependent due to time constant inequalities. Changes in inflation rate did not affect Ers, while RT increased with increasing flow. 相似文献
4.
Interrupter technique for measurement of respiratory mechanics in anesthetized humans 总被引:1,自引:0,他引:1
Gottfried S. B.; Higgs B. D.; Rossi A.; Carli F.; Mengeot P. M.; Calverly P. M.; Zocchi L.; Milic-Emili J. 《Journal of applied physiology》1985,59(2):647-652
Flow (V), volume (V), and tracheal pressure (Ptr) were measured throughout a series of brief (100 ms) interruptions of expiratory V in six patients during anesthesia (halothane-N2O) and anesthesia-paralysis (succinylcholine). For the latter part of spontaneous expiration and throughout passive deflation during muscle paralysis, a plateau in postinterruption Ptr was observed, indicating respiratory muscle relaxation. Under these conditions, passive elastance of the total respiratory system (Ers) was determined as the plateau in postinterruption Ptr divided by the corresponding V. The pressure-flow relationship of the total system was determined by plotting the plateau in Ptr during interruption against the immediately preceding V. Ers averaged 23.5 +/- 1.9 (SD) cmH2O X l-1 during anesthesia and 25.5 +/- 5.4 cmH2O X l-1 during anesthesia-paralysis. Corresponding values of total respiratory system resistance were 2.0 +/- 0.8 and 1.9 +/- 0.6 cmH2O X l-1 X s, respectively. Respiratory mechanics determined during anesthesia paralysis using the single-breath method (W.A. Zin, L. D. Pengelly, and J. Milic-Emili, J. Appl. Physiol. 52: 1266-1271, 1982) were also similar. Early in spontaneous expiration, however, Ptr increased progressively during the period of interruption, reflecting the presence of gradually decreasing antagonistic (postinspiratory) pressure of the inspiratory muscles. In conclusion, the interrupter technique allows for simultaneous determination of the passive elastic as well as flow-resistive properties of the total respiratory system. The presence of a plateau in postinterruption Ptr may be employed as a useful and simple criterion to confirm the presence of respiratory muscle relaxation. 相似文献
5.
6.
P K Behrakis B D Higgs A Baydur W A Zin J Milic-Emili 《Journal of applied physiology (Bethesda, Md. : 1985)》1983,55(4):1085-1092
In six spontaneously breathing anesthetized subjects [halothane approximately 1 maximum anesthetic concentration (MAC), 70% N2O-30% O2], we measured flow (V), volume (V), and tracheal pressure (Ptr). With airway occluded at end-inspiration tidal volume (VT), we measured Ptr when the subjects relaxed the respiratory muscles. Dividing relaxed Ptr by VT, total respiratory system elastance (Ers) was obtained. With the subject still relaxed, the occlusion was released to obtain the V-V relationship during the ensuing relaxed expiration. Under these conditions, the expiratory driving pressure is V X Ers, and thus the pressure-flow relationship of the system can be obtained. By subtracting the flow resistance of equipment, the intrinsic respiratory flow resistance (Rrs) is obtained. Similar measurements were repeated during anesthesia-paralysis (succinylcholine). Ers averaged 23.9 +/- 4 (+/- SD) during anesthesia and 21 +/- 1.8 cmH2O X 1(-1) during anesthesia-paralysis. The corresponding values of intrinsic Rrs were 1.6 +/- 0.7 and 1.9 +/- 0.9 cmH2O X 1(-1) X s, respectively. These results indicate that Ers increases substantially during anesthesia, whereas Rrs remains within the normal limits. Muscle paralysis has no significant effect on Ers and Rrs. We also provide the first measurements of inspiratory muscle activity and related negative work during spontaneous expiration in anesthetized humans. These show that 36-74% of the elastic energy stored during inspiration is wasted in terms of negative inspiratory muscle work. 相似文献
7.
De novo truncation of chromosome 16p and healing with (TTAGGG)n in the alpha-thalassemia/mental retardation syndrome (ATR-16). 总被引:12,自引:7,他引:5
J Lamb P C Harris A O Wilkie W G Wood J G Dauwerse D R Higgs 《American journal of human genetics》1993,52(4):668-676
We have previously described a series of patients in whom the deletion of 1-2 megabases (Mb) of DNA from the tip of the short arm of chromosome 16 (band 16p13.3) is associated with alpha-thalassemia/mental retardation syndrome (ATR-16). We now show that one of these patients has a de novo truncation of the terminal 2 Mb of chromosome 16p and that telomeric sequence (TTAGGG)n has been added at the site of breakage. This suggests that the chromosomal break, which is paternal in origin and which probably arose at meiosis, has been stabilized in vivo by the direct addition of the telomeric sequence. Sequence comparisons of this breakpoint with that of a previously described chromosomal truncation (alpha alpha)TI do not reveal extensive sequence homology. However, both breakpoints show minimal complementarity (3-4 bp) to the proposed RNA template of human telomerase at the site at which telomere repeats have been added. Unlike previously characterized individuals with ATR-16, the clinical features of this patient appear to be solely due to monosomy for the terminal portion of 16p13.3. The identification of further patients with "pure" monosomy for the tip of chromosome 16p will be important for defining the loci contributing to the phenotype of this syndrome. 相似文献
8.
9.
In the rat paw prostacyclin was 5–10 times less potent than PGE2 in causing oedema, and 5 times less potent in potentiating carrageenin-induced oedema, which it did in a dose-related manner. Prostacyclin was 5 times more potent than PGE2 in producing hyperalgesia and as potent as PGE2 in restoring carrageenin-induced hyperalgesia. The effects on oedema were longer lasting than those on hyperalgesia.6-oxo-PGF1α was 500 times less potent than PGE2 in causing oedema by itself and in potentiating carrageenininduced oedema. It had no hyperalgesic activity in this test. 相似文献
10.
Four unusual pregnane derivatives, 5alpha-pregna-1,20-dien-3-one (1), 1,4,20-pregnatrien-3-one (3), 5alpha-pregn-20-en-3alpha-o1 o-acetate (4), and 5alpha-pregn-20-en-1alpha,3alpha-diol 3-acetate (6) have been isolated from an unidentified soft coral from Canton Island. 相似文献