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1.
ABSTRACT

The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization.  相似文献   
2.
To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions.  相似文献   
3.
We report the MRI features in a series of four patients with primary angiitis of the central nervous system (PACNS). Based on MRI features, clinical presentation, paraclinical investigations and laboratory tests, including cerebrospinal fluid (CSF) analysis, various differentials were considered. In two patients with MRI findings of cortical, subcortical and deep white matter lesions, lack of mass effect, focal areas of bleed and heterogeneous parenchymal, leptomeningeal or pial enhancement and a normal magnetic resonance angiography, a differential diagnosis of primary angiitis of the CNS was also considered. In all patients, an open brain biopsy was advised to establish a definitive diagnosis of PACNS. Here, we briefly discuss the MRI features, correlation with clinical presentation and paraclinical parameters for the diagnosis of this entity. We also briefly review the literature.  相似文献   
4.
Abstract This paper examines the impact of medical technology on the careers of people with post-polio respiratory disability. The data have been taken from multiple in-depth interviews with ten people who contracted polio during the epidemics of the early 1950s, all of whom used or had used a variety of methods of mechanical respiratory support. It focuses on ideologies of disability and the adoption of technology, the management of respiratory insufficiency and strategies of'trading off whereby the benefits of technology are maximized and the costs minimized. While technology made an enormous contribution to the quality of life of these people, the problems it created transformed both their experience of the illness and the character of their everyday existence.  相似文献   
5.
Paroxysmal dyskinesias (PxDs) are involuntary, episodic movements that include paroxysmal kinesigenic (PKD), paroxysmal nonkinesigenic (PNKD), and paroxysmal hypnogenic (PHD) varieties. Although most PxDs are primary (idiopathic or genetic), we found 17 of our 76 patients with PxD (22%) to have an identifiable cause for their PxD (10 men; mean age, 41.4 years). Causes included peripheral trauma (in three patients), vascular lesions (in four), central trauma (in four), kernicterus (in two), multiple sclerosis (in one), cytomegalovirus encephalitis (in one), meningovascular syphilis (in one), and migraine (in one). The latency from insult to symptom onset ranged from days (trauma) to 18 years (kernicterus), with a mean of 3 years. Nine patients had PNKD, two had PKD, five had mixed PKD/PNKD, and one had PHD. Hemidystonia was the most common expression of the paroxysmal movement disorder, present in 11 patients. Both of the patients with PKD had symptom durations of <5 minutes. Symptom duration ranged from 10 seconds to 15 days for PNKD and from 5 minutes to 45 minutes for mixed PKD/PNKD. There were no uniformly effective therapies, but anticonvulsant drugs, clonazepam, and botulinum toxin injections were the most beneficial. Awareness of the variable phenomenology and the spectrum of causes associated with secondary PxD will allow for more timely diagnosis and early intervention.  相似文献   
6.
BACKGROUND: Human serum albumin (HAS) is used to treat hypoproteinaemia in neonates and as a volume expander. The aim of this study was to quantify the decrease in serum concentration of ionized magnesium ([Mg2+]) when human serum albumin is added to neonatal serum in vitro. METHODS: Human serum albumin was added to 20 cord serum samples of term infants to reach incremental concentrations of 0 to 20.0 g/l and [Mg2+] were measured. RESULTS: Serum [Mg2+] decreased significantly with the addition of serum albumin. At incremental serum albumin concentration of 10 to 20 g/l, which is within the range of the desired aim in the treatment of hypoalbuminaemia, the magnitude of the decrease in serum [Mg2+] was approximately 0.041 to 0.052 mmol/l (10 to 13 per cent) from the average baseline value. CONCLUSION: The addition of albumin causes a decrease in [Mg2+]. From this in vitro study we speculate that fast infusion of albumin in human neonates may potentially cause a clinically significant decrease in serum [Mg2+].  相似文献   
7.
8.
Molecular chaperones assist in the biosynthesis and processing of proteins. Most chaperones are induced by physiological stresses. We have shown that dietary energy restriction decreases the mRNA and protein levels of many endoplasmic reticulum chaperones in the livers of mice. Here, we have investigated the response of chaperone mRNA to feeding. Control and 50% energy-restricted C3B10RF1 mice were deprived of food for 24 h, fed, and killed 0, 1.5, 5 or 12 h after feeding. Chaperone mRNAs were strongly induced as early as 1.5 h after feeding in control and energy-restricted mice. The integrated levels of these mRNA over 24 h were significantly lower in energy-restricted mice. The mRNA response to energy intake was mirrored over the course of days in the level of chaperone protein. A similar but smaller response to feeding was found in kidney and muscle. Puromycin and cycloheximide failed to inhibit the feeding response, suggesting that feeding releases chaperone expression from an unstable inhibitor. Studies with dibutyryl-cAMP- and glucagon-supplemented, normal and streptozotocin-diabetic mice suggest that glucagon and insulin may be mediators of the feeding response. Adrenalectomy enhanced the feeding induction, but dexamethasone administration had no effect. Thus, postprandial changes in insulin and glucagon may link chaperone gene expression to feeding, possibly in several tissues including liver.  相似文献   
9.
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant.  相似文献   
10.
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost.  相似文献   
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