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1.
The political disintegration of former Yugoslavia inaugurated in 1991 resulted in the decentralization of health systems in the federation's successor nation-states. Efforts by the Open Society Institute improved public health planning and management needs consequent to health sector changes. Beginning in Croatia in 2001, the Institute developed ongoing collaborations between Andrija Stampar School of Public Health and the US Centers for Disease Control and Prevention. In 2003 and 2004, it expanded its project to include the republics of Macedonia and of Serbia and Montenegro.  相似文献   
2.
A case is reported of recurrent laryngotracheoesophageal cleft following two attempted repairs. The anterior approach to the larynx and trachea provided excellent exposure for defining the extent of the recurrent cleft, and allowed precise anatomic repair. Neurovascular structures were easily avoided by this operative method. Of 170 clefts reported in the literature, 19 recurred necessitating reoperation. The anterior approach to the larynx and trachea is appropriate in recurrent clefts and may be preferable at the initial repair.  相似文献   
3.
The functional significance of presynaptic alpha-receptor modulation of sympathetic nerves was examined in vivo in the canine renal vascular bed. In pentobarbital-anesthetized dogs, the vasoconstrictor response to renal nerve stimulation and exogenous norepinephrine was compared before and during intra-arterial infusions of epinephrine, oxymetazoline, clonidine, and norepinephrine. Only epinephrine produced a modest decrease in stimulation-induced vasoconstriction at 1 Hz. After pretreatment with desipramine, intra-arterial infusions of epinephrine or norepinephrine did not alter stimulation-induced vasoconstrictor responses relative to exogenous norepinephrine. Further, neither yohimbine nor phentolamine (10(-9) to 10(-3) g, intra-arterial) produced a distinctly increased vasoconstrictor response to nerve stimulation relative to exogenous norepinephrine. Thus, studies using alpha-receptor agonists, antagonists, and inhibition of neuronal uptake failed to reveal a physiologically significant alpha-receptor-mediated negative feedback mechanism for stimulation-induced vasoconstriction in the canine renal vascular bed.  相似文献   
4.
Pramipexole (PPX) is a full intrinsic activity, direct-acting dopamine (DA) agonist possessing 7-fold higher affinity for D3 than for D2 receptors. It also is a potent antioxidant. PPX was previously shown to be neuroprotective because it dose dependently attenuated the DA neuron loss produced by levodopa in mesencephalic cultures. Several different drugs with properties similar to PPX were studied here to better understand the mechanism or mechanisms responsible for this neuroprotective effect. The D3-preferring agonist 7-hydroxy-diphenylaminotetralin (7-OH-DPAT) and the D3 antagonist U99194, respectively, increased and decreased the neuroprotective effects of PPX in a dose-dependent fashion. Addition of the selective D2 agonist U95666 or the D2/D3 antagonists domperidone or raclopride did not affect PPX's neuroprotective effect. Interestingly, 7-OH-DPAT by itself did not attenuate the DA neuron loss produced by levodopa. However, when 7-OH-DPAT was combined with a low dose of the antioxidants U101033E or alpha-tocopherol, the toxic effects of levodopa were attenuated. Similar results were observed when the D3-preferring agonist PD128, 907 was studied. In addition, media conditioned by exposure of mesencephalic cultures incubated with all D3-preferring agonists studied was shown to enhance the growth of DA neurons in freshly harvested recipient cultures implicating a D3-mediated trophic activity in the neuroprotective effect. These data suggest that PPX's neuroprotective actions in the levodopa toxicity model are a consequence of its combined actions as a D3 receptor agonist and an antioxidant.  相似文献   
5.
Striatal trophic activity is reduced in the aged rat brain   总被引:2,自引:0,他引:2  
Our previous studies demonstrated that the survival of a mesencephalic graft was reduced in aged animals suggesting an age-related decline in target-derived neurotrophic activity. We tested this hypothesis by examining dopamine (DA) and trophic activities from the striatum of intact or unilateral 6-hydroxydopamine (6-OHDA) lesioned rats of increasing age. Fisher 344 rats were 4, 12, 18, and 23 months old (m.o.) at sacrifice. Half the animals had received unilateral 6-OHDA lesions of the mesostriatal DA pathway 8 weeks earlier. Striatal tissue punches were analyzed for DA, homovanillic acid (HVA), and DA activity (HVA/DA) using HPLC. The remainder of the striatal tissue was homogenized to generate tissue extracts which were added to E14.5 ventral mesencephalic cultures to test trophic activity. In the non-lesioned animals, striatal DA was reduced and striatal DA activity was increased in the 18 and 23 m.o. animals relative to the 4 and 12 m.o. animals. Striatal trophic activity was inversely related to age. In the lesioned animals, striatal DA ipsilateral to 6-OHDA infusion was below detection limits while the contralateral striatum exhibited age-related changes in DA similar to those seen in the non-lesioned animals. In 4 m.o. lesioned rats, striatal trophic activity ipsilateral to 6-OHDA infusion was elevated by 26% relative to the contralateral side. The ipsi/contra-lateral differences in striatal trophic activity were reduced in 12 m.o. animals and absent in the 18 and 23 m.o. groups. These data suggest that advancing age is associated with a reduction in striatal DA as well as trophic activity. Moreover, the aged striatum loses its ability to biochemically and trophically compensate for DA reduction and therefore may represent a more challenging environment for the survival, growth, and function of a fetal graft.  相似文献   
6.
Despite many recent efforts to predict and control emerging infectious disease threats to humans, we failed to anticipate the zoonotic viruses which led to pandemics in 2009 and 2020. The morbidity, mortality, and economic costs of these pandemics have been staggering. We desperately need a more targeted, cost-efficient, and sustainable strategy to detect and mitigate future zoonotic respiratory virus threats. Evidence suggests that the transition from an animal virus to a human pathogen is incremental and requires a considerable number of spillover events and considerable time before a pandemic variant emerges. This evolutionary view argues for the refocusing of public health resources on novel respiratory virus surveillance at human–animal interfaces in geographical hotspots for emerging infectious diseases. Where human–animal interface surveillance is not possible, a secondary high-yield, cost-efficient strategy is to conduct novel respiratory virus surveillance among pneumonia patients in these same hotspots. When novel pathogens are discovered, they must be quickly assessed for their human risk and, if indicated, mitigation strategies initiated. In this review, we discuss the most common respiratory virus threats, current efforts at early emerging pathogen detection, and propose and defend new molecular pathogen discovery strategies with the goal of preempting future pandemics.  相似文献   
7.
This is the first reported case in which a Logothetopulos pack was utilized to achieve pelvic hemostasis in a patient requiring a cesarean hysterectomy for placenta accreta with postpartum hemorrhage. The Logothetopulos pack is an easily constructed gauze tamponade method that proved to be life-saving in this case.  相似文献   
8.
Dopamine and dobutamine are sympathomimetic amines with divergent peripheral vascular actions. The renal, mesenteric, and femoral vascular and total systemic hemodynamic effects of these amines were compared in pentobarbital-anesthetized dogs. Both agents increased myocardial contractility. Infusion rates of dopamine greater than 5 mug per kilogram per minute increased mean aortic pressure. Dobutamine increased mean aortic pressure. Dobutamine in creased the systolic pressure but did not alter mean aortic pressure. Dobutamine increased cardiac output more than dopamine. Dopamine infusions up to 10 mug per kilogram per minute increased renal and mesenteric blood flow and decreased vascular resistance. Dobutamine had negligible effects on the renal or mesenteric blood flow but produced dose-related increases in femoral blood flow. Dopamine did not significantly alter femoral hemodynamics. These results more clearly define the systemic and regional vascular hemodynamic effects of these agents.  相似文献   
9.
Stage 4S neuroblastoma is an unusual malignancy that has an excellent prognosis, except in young infants. A 2-month-old with 4S neuroblastoma complicated by massive hepatomegaly, managed by abdominal decompression surgery and a negative-pressure dressing system is presented. Diffuse alveolar hemorrhage also developed, which was treated with high-dose corticosteroids.  相似文献   
10.
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