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101.
The argon laser set at 50 mum, 100-150 mW, o-2 s occluded corneal blood vessels in pigmented Dutch rabbits provided the corneal responsible for inducing vascularization was inactive. After arterial treatment with the argon laser retrograde flow in untreated veins was demonstrated by fluorescein angiography. Therefore all corneal new vessels should be treated, not just arteries. Minimal iris damage complicated the laser therapy, but this was not thought necessarily to contraindicate the use of the argon laser to treat corneal blood vessels in man. The iris damage was associated with outpouring of aqueous from the ciliary processes, and it took up to a week for the blood-aqueous barrier to return to its normal state.  相似文献   
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Values for the resistances shunting sections of tapped potentiometers are rapidly computed from simple data using two alternative digital-computer programs which provide potentiometer-network designs, having a specified accuracy, for arbitrary monotonic and nonmonotonic functions.  相似文献   
106.
A microinjection of endothelin-1 (ET-1; 10 pmol) into the superior colliculus (SC) of anaesthetised rats caused a decrease in blood pressure. Microinjection into the same nucleus of Nomega-nitro-L-arginine methyl ester (L-NAME; 0.1, 0.5, 1 micromol), an L-arginine analogue and a potent inhibitor of nitric oxide (NO) synthase, increased the basal mean arterial blood pressure. Treatment of SC with L-NAME (1 micromol) did not affect the depressor response induced by injection of ET-1 (10 pmol), into the SC, at the peak of the pressor response to L-NAME. In addition, L-arginine L-ARG) (1 micromol), the substrate for NO synthase, microinjected into the superior colliculus prior to ET-1 did not significantly increase the depressor response to ET-1. These findings, therefore, suggest that within the SC the nitric oxide synthesis does not affect depressor responses induced by ET-1.(c) 1998 The Italian Pharmacological Society  相似文献   
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Unlike other forms of tuberculosis, tuberculous cerebral abscess is a rare complication of human immunodeficiency virus (HIV) infection and usually presents at a late stage of the disease. This article describes a case of tuberculous cerebral abscess in an HIV-infected patient that was effectively treated with surgery and chemotherapy. The patient has survived more than 5 1/2 years since being diagnosed and remains in good health.  相似文献   
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The racemic 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) is currently used at several centers for myocardial metabolic imaging with SPECT. Recently, the 3(R)-BMIPP isomer showed a 20%-25% higher myocardial uptake and lower liver uptake than 3(S)-BMIPP in fasted rats. The aim of this study was to determine if these differences in myocardial and liver uptake also occur in humans. METHODS: Iodine-123-labeled 3(R)-BMIPP and 3(S)-BMIPP isomers were injected at rest, on two separate days, in six patients with stable coronary artery disease. Dual-head, whole-body scintigraphy was performed 20 min and 3 hr after injection. SPECT cardiac imaging was performed 60 min after injection. RESULTS: Myocardial activity averaged (% injected dose +/- s.d.) 3.15 +/- 0.49 versus 3.01 +/- 0.44 at 20 min (p = ns) and 2.64 +/- 0.38 versus 2.55 +/- 0.41 at 3 hr postinjection (p = ns) for the 3(R)-BMIPP and 3(S)-BMIPP isomers, respectively. Liver activity averaged 9.50 +/- 1.18 versus 9.44 +/- 0.66 at 20 min and 5.33 +/- 0.64 versus 5.43 +/- 0.66 at 3 hr, respectively (p = ns). SPECT showed no difference in the distribution of the two isomers between normal and infarcted myocardium. CONCLUSION: There is no significant difference in myocardial and liver distribution of the 3(R)-BMIPP and 3(S)-BMIPP isomers in humans.  相似文献   
109.
The successful conclusion of an intercorrelation program developed in the US Breeder program has provided significant insight on the factors governing the swelling that develops in ion-bombardment studies and its relationship to the swelling that occurs during neutron irradiation. It appears that the injected interstitial or a related phenomenon exerts a pronounced influence on ion-induced swelling. This conclusion has ramifications with respect to the conduct and interpretation of ion irradiation experiments employed to study the effect of helium or composition on swelling.  相似文献   
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