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991.
A series of C(3)-cyclopropyl cephems and carbacephems has been prepared by palladium catalyzed addition of diazomethane to the corresponding C(3)-vinyl derivatives. The phenylglycyl cyclopropyl cephem derivatives exhibit better Gram-positive activity than cephalexin or cefaclor, while the aminothiazole oxime cyclopropyl cephem derivatives were not as active as the corresponding C(3)-vinyl cephems. 相似文献
992.
R D Montgomery 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1989,83(6):724-728
The clinical profile of tropical spastic paraparesis (TSP), described in scattered tropical and subtropical territories over the past 30 years, has been more clearly defined since the discovery of its direct association with human T lymphotropic virus type 1 (HTLV-1). A chronic disease of adults, commoner in women, it usually presents as a progressive spastic paraparesis with sphincter disturbance, sometimes with backache and lower limb sensory disorder. Most cases are chair-bound within 10 years. Histology reveals a chronic lymphocytic meningomyelopathy, predominantly in the spinal cord, together with long tract demyelination and hyalinoid thickening of the media and adventitia of small blood vessels. Geographical areas of high prevalence of TSP are known in the Caribbean, South America, South Africa, southern Japan, the Seychelles and probably in India, and it is sparsely endemic elsewhere. The virus appears to exist within lymphocytes for long periods. Vertical transmission occurs postnatally, and sexual and transfusion infection are also recognized, but much remains to be clarified regarding its pathogenesis and epidemiology. 相似文献
993.
994.
In acute experiments on anesthetized cats with total ischemia of the brain (15-minute arrest of blood autoperfusion of the cerebral vessels by a stable blood volume) it was shown that euphylline and no-shpa administered before ischemia or in the early period after ischemia inhibit or prevent the development of the postischemic phenomenon of non-recovery of the cerebral blood flow. The two drugs contributed to survival of albino rats following the brain ischemia produced by ligation of both carotid arteries. 相似文献
995.
A D Costello E K Warrington 《Journal of neurology, neurosurgery, and psychiatry》1987,50(9):1110-1116
A right-handed man with a left hemisphere lesion extending into the right hemisphere, with evidence of both a left-sided neglect dyslexia and right-sided visuospatial neglect is reported. When copying simple geometric designs he omitted to copy figures on the right-hand side of the page, when bisecting lines he tended to bisect the line to the left of the line's actual centre. He had a neglect dyslexia which was characterised by paralexic errors affecting the beginning (that is, left) of words. The occurrence of these two phenomena provides evidence of a dissociation of these forms of neglect. The findings are discussed in relation to the possible mechanisms of unilateral neglect. 相似文献
996.
Participation of angiotensin II in learning and memory. III. Interactions of angiotensin II with GABAergic drugs 总被引:1,自引:0,他引:1
D Yonkov V Georgiev T Kambourova M Opitz 《Methods and findings in experimental and clinical pharmacology》1987,9(4):205-208
The experiments were carried out on male albino rats trained and tested for retention (24 hr later) in a shuttle-box. Angiotensin II (AT II) 0.10 micrograms intracerebroventricularly (i.c.v.), gamma-aminobutyric acid (GABA) 100 micrograms i.c.v., bicuculline 0.5 and 1.0 mg/kg intraperitoneally (i.p.), and picrotoxin 0.5 and 1.0 mg/kg i.p. administered independently or in combinations immediately after training. AT II was found to improve retention. GABA also facilitated retention. Combination of AT II + GABA potentiated the memory-improving effect of AT II. Bicuculline and picrotoxin at a dose of 0.5 mg/kg did not affect retention, while at a dose of 1.0 mg/kg they improved it. Combinations of AT II + bicuculline (0.5 mg/kg) and AT II + picrotoxin (0.5 mg/kg) abolished the retention-improving effect of AT II. Bicuculline (0.5 mg/kg) or picrotoxin (0.5 mg/kg) abolished the retention-facilitating effect of the combination of AT II + GABA as well as the potentiating action of GABA on the memory effect of AT II. These results suggest the participation of GABAergic transmission in the CNS in the mechanisms of the long-term memory-improving effect of AT II. 相似文献
997.
Experience with the 'skew flap' below-knee amputation 总被引:3,自引:0,他引:3
A review of 353 lower limb amputations over the last 7 years has been performed to assess the results of the skew flap myoplastic below-knee amputation which was introduced in April 1983 because of reported advantages in terms of wound healing and earlier ambulation. Comparing the first 3 1/2 year period with the second, the total number of amputations decreased by 31 per cent. The number of above-knee amputations remained similar in the two periods (82,62), whilst the number of Gritti-Stokes amputations fell from 79 to 21 (0.001 greater than P greater than 0.01). The proportion of below-knee (BK) amputations increased from 50 (23.7 per cent) to 59 (41.5 per cent) (0.01 greater than P greater than 0.025). The groups were comparable in terms of previous vascular surgery and co-existing medical conditions. The time to full stump healing was significantly shorter in the skew flap group compared with the earlier Burgess type BK amputation (P = 0.001), and there was a trend to fewer stump failures in the skew flap group. We therefore feel that the skew flap amputation gives superior results to the Burgess BK amputation in terms of healing and a lower complication rate, allowing a higher proportion of BK amputations to be performed. A prospective randomized trial of the two techniques is in hand to determine the accuracy of this hypothesis. 相似文献
998.
Ambient light affects pulse oximeters 总被引:1,自引:0,他引:1
999.
1000.
Dorsal dislocation of the ulnar styloid and extensor carpi ulnaris tendon into the distal radioulnar joint: the empty sulcus sign 总被引:1,自引:0,他引:1
Two cases of distal radioulnar joint (DRUJ) disruption and diastasis secondary to distal radial fractures were associated with displacement of the ulnar styloid and extensor carpi ulnaris (ECU) into the DRUJ. Both cases had a palpable empty ECU tendon sulcus. In one case surgical exploration revealed that the ulnar styloid, triangular fibrocartilage, and extensor carpi ulnaris tendon had dislocated into the DRUJ as a unit. The end result was good. In the second case lack of recognition and reduction of the ECU tendon and ulnar styloid led to persistent subluxation and diastasis. The end result was poor. Early recognition of the dislocation of the ulnar and ECU into the DRUJ and their significance may avoid poor results. 相似文献