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991.
D H Char J R Castro J M Quivey T L Phillips A R Irvine R D Stone S Kroll 《Ophthalmology》1989,96(12):1708-1715
The optimum radiation therapy for uveal melanoma is uncertain. Both helium ion irradiation and 125I brachytherapy have been used to treat this neoplasm. This investigation analyzed the control and complication rates of uveal melanomas treated with helium ions of 125I plaques. In both a retrospective and a prospective dynamically balanced study, the control rates appeared to be similar. There were more posterior segment complications after 125I plaques and more anterior segment complications, including neovascular glaucoma, after helium ion irradiation. The follow-up period is too short to draw definitive conclusions on the radiation complications. Overall, approximately 89% of eyes were retained and less than 4% of treated eyes were removed because of failure to control the tumor. 相似文献
992.
Effects of vasodilator drugs on venous tone in conscious rats 总被引:1,自引:0,他引:1
The dose-response effects of vasodilator drugs, nitroglycerin, sodium nitroprusside and hydralazine, on mean arterial pressure (MAP) and mean circulatory filling pressure (MCFP), an index of body venous tone, were investigated in conscious, unrestrained, intact rats as well as in rats treated with the ganglionic blocker, hexamethonium. The effects of these drugs were compared with those of the vehicle, normal saline, in control rats. In intact rats, i.v. infusion of nitroglycerin did not alter MAP while i.v. infusions of nitroprusside or hydralazine caused dose-dependent decreases in MAP. After ganglionic blockade, all three drugs decreased MAP. In intact rats, nitroglycerin and sodium nitroprusside did not affect MCFP but hydralazine increased MCFP. After treatment with hexamethonium, all three drugs decreased MCFP. The decreases in MCFP caused by nitroglycerin and nitroprusside, but not that by hydralazine, were significantly greater than the corresponding changes in control rats. Thus, in intact rats, the direct venodilator actions of nitroprusside and nitroglycerin were masked by endogenous sympathetic tone. When sympathetic nerve activity was attenuated, both nitroprusside and nitroglycerin have venodilator effects. Hydralazine, on the other hand, had insignificant venodilator effect both in the presence and absence of sympathetic reflexes. 相似文献
993.
H Ikenaga T Ogihara S Iyori S Kou H Yoshikawa M M Okura 《Postgraduate medical journal》1989,65(768):761-764
A case of a young Japanese woman with long-standing ulcerative colitis complicated by preinfarction angina due to Takayasu's aortitis is presented. Successful emergency aorto-coronary bypass operation was performed. Whether the association of these two diseases can be explained by a common mechanism is discussed. 相似文献
994.
S Watanabe K Nakano H Misumi M Yoshikai M Endo A Hashimoto H Koyanagi 《Nihon Geka Gakkai zasshi》1989,90(9):1513-1516
St. Jude Medical valve replacement was performed in 1,039 patients; 320 had aortic (AVR), 543 mitral (MVR), and 176 had double valve replacement (DVR). There were 44(4.2%) early deaths. Follow-up extended in 995 patients from 10 to 130 months, with a cumulative period of 2,730 patients-years. The overall survival rates of AVR, MVR, and DVR patients at 10 years were 60.5%, 89.6%, 90.3% respectively. The linearized incidences of valve thrombosis, thromboembolism, anticoagulation-related hemorrhage, prosthetic valve endocarditis, and significant hemolysis were as follows: 0.11%/pt-yr, 1.33%/pt-yr, 0.04%/pt-yr, 0.18%/pt-yr, and 0.11%/pt-yr, respectively. There were no structural failure after 10 years follow-up. Reoperation (explant and re-replacement or suture repair) was required in 10 patients. Seven of them had periprosthetic leakage, 2 had valve thrombosis, and one underwent reoperation because of a technical error. Actuarially over 98% of patients were free of valve-related mortality at 10 years. St. Jude Medical valve is an excellent alternative for use in the surgical treatment of valvular heart disease. 相似文献
995.
Iu A Kuchak N V Sokolovski? T F Kharchenko V Iu Romanovski? 《Gigiena truda i professional'nye zabolevaniia》1989,(9):12-14
The first phase of data bank of hazard (DBH) of polymers has been developed and put into operation on the basis of CM-computers. DBH is a factographical computer-based system of data collection, storage and processing aimed at complex assessment of material and substance hazard. Systems approach to the analysis of material's characteristics serves as a methodological basis. DBH data base includes a set of input and output documents according to 5 types of biological hazards involving sanitary and chemical surveillance, fire hazard and thermodestruction, the data on material's microbiologic resistance, their electrifying and toxicohygienic characteristics. DUAMC-3 operational system, DUAMC. DBH software are included into the system of data banks of materials' technological properties. 相似文献
996.
997.
A sample of 110 consecutive first admission young schizophrenic patients treated between 1964 and 1967 was rediagnosed in 1981. Among 92 survivors, 27 could be labelled as paraphrenics. From information available at inception 97 variables were coded covering such areas as personality, previous disturbances, age and type of onset, and symptoms around admission. Sixty-three out of 97 variables were hypothesized to differentiate, at admission, future paraphrenics from the rest of the sample. Paraphrenics were found to have had less contact disturbance, better self-esteem, less neurotic symptoms in adolescence and childhood, and less complaints of unhappiness when growing up. They had more regressive and paranoid symptoms at admission, were older at onset of the disease, which was more acute, more often connected with precipitating events, and confusion. Certain non-regressive symptoms such as brooding, anhedonia and concentration difficulties were less common. A discriminant analysis yielded a proportion of correct predictions = 0.64 (p less than 0.05). The results are in accordance with the theory of more favourable energetic and organizational capacity in paranoid schizophrenics as compared with non-paranoids. 相似文献
998.
Fatigue during stretch-shortening cycle exercises: changes in mechanical performance of human skeletal muscle 总被引:6,自引:0,他引:6
Stretch-shortening cycle (SSC), which is a normal contraction behavior of muscle, was used as a model to investigate muscular fatigue. Nine male volunteers were subjected to 100 repeated and exhaustive SSC contractions of the forearm extensors using a special sledge apparatus incorporating a force plate system. The fatigue contractions were performed on submaximal levels but the before-after comparison also included maximal drop-jump condition on the sledge as well as falls on to the floor. The results indicated that in the 100 submaximal SSCs the fatigue was characterized by increases in the contact times for both the eccentric and concentric phases of SSC, but the influence was more pronounced on the concentric part. The force-time curves during contact on the platform were influenced by fatigue so that the initial force peak became higher and the subsequent initial drop of force more pronounced. During submaximal and maximal drops, the angular velocities changed in the two phases of SSC. With progressing fatigue, the eccentric maximal angular velocity increased and the corresponding concentric velocities decreased. These changes were accompanied by slight changes in the elbow joint mechanism with respect to the contact, release, and maximal flexion angles. The results suggest that repeated SSC induces fatigue and the fatigue effects on the mechanical behavior of the muscle are very much similar to those induced by either isometric or concentric fatigue contractions. However, the transfer of the energy between eccentric and concentric phases was drastically reduced and this implies that SSCs can be used effectively to examine the fatiguability of the system regulating muscle stiffness during exercise. 相似文献
999.
In the cat synapses between vesicle containing profiles were observed in ventral and dorsolateral pontine nuclei. The presynaptic elements consisted of two types of axon terminals: axon terminals characterized by a population of small (38-40 nm) round synaptic vesicles (SSV) and axon terminals containing pleomorphic synaptic vesicles (PSV). The postsynaptic pale elements (PP) had pleomorphic vesicles and some features attributed to dendrites. In the dorsolateral pontine nucleus most of PP profiles took part in serial synapses, usually as an intermediate component, they were rarely observed in triads. On the basis of their electron microscopical appearance and synaptic relations they might be considered to represent a dendritic part of putative interneurons. 相似文献
1000.
In the upper limb, diffuse cavernous haemangiomas occur infrequently but their treatment is often unsatisfactory and the result of surgical excision disappointing. Four cases of these diffuse haemangiomas are described and their management discussed. 相似文献