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排序方式: 共有4099条查询结果,搜索用时 15 毫秒
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Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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Tears of the retinal pigment epithelium (RPE) are a recognized complication of pigment epithelium detachments associated with age-related macular degeneration (ARMD). The RPE tears are often associated with a poor visual prognosis and typically do not occur with subretinal hemorrhage. We report the case of a 76-year-old man with ARMD who developed an RPE tear associated with subretinal hemorrhage, without a demonstrable subretinal neovascular membrane. Temporally, there was a marked decrease in his vision that returned to his earlier baseline visual acuity over the course of six months of observation. 相似文献
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Central and peripheral effects of oxytocin administration in prairie voles (Microtus ochrogaster) 总被引:3,自引:0,他引:3
The present study examined the hypothesis that oxytocin (OT) may influence female sexual behavior in prairie voles (Microtus ochrogaster). The effectiveness of OT to induce sexual behavior was tested in ovariectomized females that were injected daily with estradiol benzoate (EB, 0.02 micrograms, twice), a dose insufficient for estrus induction. On the third day females received intracerebroventricular (ICV) injections of OT (1, 300, or 1000 ng) or saline vehicle. In the presence of minimal estrogen stimulation, OT did not induce sexual receptivity, or influence autogrooming or other social interactions. The behavioral effects of OT were examined in another group of ovariectomized females that received daily oil or EB injections (10 micrograms, twice) followed on the third day by either ICV (1, 300, or 1000 ng) or intraperitoneal (IP) (1, 3, or 10 micrograms) injections of OT. Among EB-treated females, only those in confirmed estrus, prior to ICV or IP injection, were included in these studies. There was a dose-related decrease in the percentage of females that remained in behavioral estrus after ICV OT. In those females that continued to show sexual behavior, lordosis frequencies and durations were unaffected by ICV OT. Nonsexual behavior did not differ between mated females and those exhibiting OT-inhibited sexual behavior. In females that were EB-treated, autogrooming and side-by-side behavior increased after ICV OT, while there was a decline in aggression. Female sexual and nonsexual behaviors were not significantly affected by IP OT.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
S.L. Atkin A.M. Coady D. Horton N. Sutaria L. Sellars C. Walton 《Diabetic medicine》1995,12(3):267-270
A 15-year-old girl presented de novo in diabetic ketoacidosis having been comatose for 24 h (day 1). A CT scan and lumbar puncture performed on admission were normal and her conscious level slowly improved over several days. On day 7 she had central neurological signs of bilateral knee clonus and an extensor plantar response. In addition, she had developed lower motor neurological signs of an ulnar nerve palsy of the left forearm, and ulnar, median, and radial nerve palsies of the right forearm. Magnetic resonance imaging (MRI), performed on day 12, showed multiple small cerebral haematomata with appearances at least several days of age. The scattered lesions were localized particularly to the parieto-occipital region, with sparing of the basal ganglia and without cerebral oedema, a novel feature not previously described in juvenile ketoacidosis. Four months later there was minimal residual disability of her right arm. The clinical findings together with the MRI images suggested that the peripheral nerve and central lesions were temporally related, suggesting a common aetiology. However, it is likely that MRI showed cerebral lesions which may have been missed by the conventional CT scanning performed initially. 相似文献
8.
Crohn's disease of the vulva 总被引:1,自引:0,他引:1
We have reported a case of Crohn's disease of the vulva, an unusual manifestation of inflammatory bowel disease. The initial management of this condition should be medical, using antibiotics and established regimens to control gastrointestinal symptoms. Surgical therapy is appropriate when medical management fails, as it did in our patient. 相似文献
9.
D. Chemla P. Démolis M. Thyrault D. Annane Y. Lecarpentier and JF Giudicelli 《Fundamental & clinical pharmacology》1996,10(4):393-399
Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (Vm ) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (Gmax = +dV/dtmax ). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, Gmax was of a similar magnitude (551 ±30 and 555 ± 44 cm/s2 , respectively) despite major differences in the respective D, Vm , Q and R values. In neither artery was there a relationship between Gmax and either resting Q or R. At the brachial artery level, Gmax was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between Gmax and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow. 相似文献
10.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献