对乙酰氨基酚引起的急性肝衰竭：一项美国多中心前瞻性研究结果

严重的对乙酰氨基酚肝毒性常常会引起急性肝衰竭（ALF），作者在美国的22所三级护理中心调查了由对乙酰氨基酚引起的肝衰竭的发生率、危险因素和预后，用超过6年的时间收集到662例完全符合ALF（包括肝源性凝血症和肝性脑病）标准的患者资料，详细分析后发现：其中有275例（45％）是由对乙酰氨基酚引起的。调查发现，对乙酰氨基酚相关性ALF的年度百分比由1998年的28％上升至2003年的51％。对乙酰氨基酚的中位摄入量为24g（相当于48个高含量的片剂）。在上述275例中，误服过量者有131例（48％），有意服用者（即有自杀倾向者）有122例（44％），还有22例（8％）为不明意图。在误服组中38％同时服用了两种或多种对乙酰氨基酚制剂，63％患者服用了含有镇静剂的复合制剂。据报道，81％患者因为急性或慢性疼痛误服了对乙酰氨基酚和（或）其他镇痛剂。总体上，有178例研究对象（65％）存活，74例（27％）未经肝移植而死亡，23例（8％）进行了肝移植，其中71％的患者仅存活了3周。未接受移植的存活率和肝移植存活率在误服组和有意服用组差别不明显。     

Production of nitrite by primary rat astrocytes in response to pneumococci

Recent studies using a rat model of pneumococcal meningitis have shown that nitric oxide synthase (NOS) inhibitors greatly attenuated microvascular changes and brain edema formation. The site of NO production during bacterial meningitis is unknown. In this study we tested whether primary astrocyte cultures from neonatal rat cortex can be induced to release NO upon stimulation with pneumococci. NO production was assessed by measuring nitrite in the cell culture supernatant using the Griess reaction. Stimulation with heat-killed unencapsulated pneumococci (HKP) increased nitrite concentrations in astrocyte culture supernatants in a dose-dependent fashion. Administration of AT-nitro-L-arginine (L-NA), aminoguanidine, L-canavanine, cycloheximide, and dexamethasone prevented the increase in nitrite concentrations. Addition of L-arginine, but not of o-arginine, partially reversed the inhibitory effect of L-NA. Administration of SOD increased nitrite accumulation. Moreover, at 72 h after stimulation with heat-killed pneumococci (10⁷ cfu/ml) astrocytes showed an inducible NOS-like immunoreactivity. Accumulation of nitrite was also observed when rat cerebellar neurons and microglia were stimulated with HKP, whereas there was only a slight increase of nitrite in media of rat C6 glioma cells, but no increase of nitrite when the human glioblastoma cell line LN-229 was stimulated with HKP. There was a stronger increase in nitrite levels when astrocytes from Lewis rats were used compared to that from Wistar rats. In conclusion, our study indicates that astrocytes, neurons and microglia are inducible for NO production upon stimulation with pneumococci.     

Chronic anxiolytic treatment effects on conflict behavior in the rat

The present studies examined the effects of chronic posttest treatment with the antipanic agent alprazolam (ALP) or the traditional anxiolytic agents chlordiazepoxide (CDP) and phenobarbital (PhB) on conflict behavior. In daily ten-minute sessions, water-deprived rats were trained to drink from a tube which was occasionally electrified (0.25 or 0.5 mA). Electrification was signalled by a tone. Chronic ALP (10 mg/kg/day), CDP (40 mg/kg/day), PhB (80 mg/kg/day) or vehicle were injected IP after conflict testing (in some experiments again 12-16 hours later) for a minimum of 6 weeks. Chronic ALP (but not CDP or PhB) resulted in a time-dependent increase in punished responding, with a latency to onset of 3-4 weeks; this effect was not antagonized by the benzodiazepine antagonist Ro15-1788. These data support the hypothesis that conflict paradigms may serve as animal models for the study of antipanic agents. Moreover, these data suggest that not all anxiolytics will exhibit antipanic efficacy.     

A rare thyroid vascular anomaly: a unique thyroid artery arising from the right carotid bifurcation

The evidence of thyroid vascular anomalies is is frequent and may manifest itself with an anatomic alteration. The absence of the inferior thyroid artery is reported in 1% of the cases, while a thyroid artery arising from the common carotid artery has been found in 2% of examined patients. In the observed case we retain that the rarity is not only due to the contemporary presence of two anomalies, but also to the presence of an anomalous vessel which arises from right carotideal bifurcation and bloody supplies either right lobular or left lobular of thyroid, thus resulting the sole gland's arterial vessel.     

The delivery of preventive services in primary care practices according to chronic disease status.

OBJECTIVES: The current study examined the relationship between chronic disease status and the receipt of cancer preventive services over a 3-year period. METHODS: Adults (n = 4320) cared for by 167 nonacademic physicians in 42 primary care group practices were studied. Medical records were audited for each patient, as were patient responses to two questionnaires assessing health and sociodemographic characteristics. RESULTS: While the odds of having received counseling to obtain regular checkups were increased for men (1.56) and women (1.46) with hypertension, the odds were reduced (range = 0.32 to 0.81) for having received a sigmoidoscopy (women with diabetes or hypertension, men with hypertension or heart disease), fecal occult blood test (men with diabetes or heart disease, women with heart disease), mammogram or counseling about smoking (women with diabetes), clinical breast exam (women with heart disease), and Pap test (women with diabetes or heart disease). CONCLUSIONS: The presence of common chronic health problems in older adults is associated with lower levels of cancer screening services.