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991.
992.
993.
Pneumocystis carinii pneumonia is a major cause of morbidity and mortality in patients with the acquired immunodeficiency syndrome. When P. carinii is disseminated, the choroid may be involved and the infection is often fatal. We examined, treated, and followed up two patients who developed choroidal lesions typical of P. carinii while taking aerosolized pentamidine for prophylaxis. The choroidal lesions gradually resolved after three weeks of therapy with intravenous trimethoprim and sulfamethoxazole in one patient, and after three weeks of therapy with parenteral pentamidine in the other patient. The patients did not have clinical or laboratory evidence of P. carinii infection other than in the eye. It thus appears that early ophthalmologic examination may detect disease before it is threatening to sight and allow systemic therapy to be instituted before widely disseminated infection results in a fatal outcome.  相似文献   
994.
995.
Improved selectivity to one chemical shift component was obtained using simultaneous slice-selective and chemical shift-selective excitation in sequences with usual spin-echo refocusing. The new type of sequences can be applied on modern whole-body units and permits multislice operation. Spatial-spectral excitation is based on prior research in this field, but the proposed improved version provides off-center slice excitation by the usual processing of the RF pulse envelopes. In addition, no irregular gradient shapes are necessary. The required B0 homogeneity of the new method is similar to conventional “fat-sat” techniques. In contrast to fat-sat methods, selectivity to water is not reduced by unavoidable mis-adjustments of the transmitter or B1 field inhomogeneities in the newly developed approach. Thus, the reported method has the potential to replace standard frequency selective fat-sat sequences for most applications.  相似文献   
996.
A 25 year old woman presented with severe myocardial dysfunction. Laboratory tests showed hypocalcaemia caused by hypoparathyroidism. After the restoration of normal concentrations of serum total and free ionic calcium indices of left ventricular function returned to normal and her symptoms disappeared.  相似文献   
997.
998.
Separate age groups of autoimmune NZB/BINJ and non-autoimmune C57BL/BNNia mice were compared for habituation of locomotor activity and its retention over four separate testing sessions spaced at 24-hr intervals. A decline in locomotion (distance in cm) or in the time spent in the center zone as a function of sessions was taken to indicate retention for habituation to stimuli within the test apparatus. The time spent in the center zone decreased as a function of sessions in young and mature C57BL/6NNia mice but failed to show reliable between-session decreases in old (24–26-months) C57BL/ 6NNia mice. When compared with the old C57BL/6NNia mice, young NZB/BINJ mice showed similar impairments. Habituation of locomotion was present in all age groups of C57BL/6NNia mice, but absent in NZB/BINJ mice regardless of age. The retention impairments of 2–4 month old NZB/BINJ mice were attenuated when i.p. injections of 0.04–0.16 mg physostigmine/kg were given just following each habituation session. The effectiveness of physostigmine was substantially reduced when injections were delayed by 20 min or longer following each habituation session. The time-dependent reversal of the aged-like retention deficits by the cholinesterase inhibitor, physostigmine, suggests that cholinergic modulation of memory storage processes may be impaired in NZB/BINJ mice.  相似文献   
999.
1000.
A case of spontaneous intra-aneurysmal thrombosis, verified angiographically, is reported in a patient with subarachnoid hemorrhage and without surgical intervention. The frequency of such an occurence and the factors involved are reviewed and discussed.  相似文献   
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