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71.
72.
Skaggs DL Roy AK Vitale MG Pfiefer C Baird G Femino D Kay RM 《Journal of pediatric orthopedics》2002,22(2):265-267
The purpose of this study was to investigate the quality of evaluation and management of children requiring timely orthopaedic surgery before admission to a tertiary pediatric facility. A retrospective chart review was performed on 372 consecutive children who underwent orthopaedic surgery for a diagnosis of fracture, infection, slipped capital femoral epiphysis (SCFE), or compartment syndrome during a 22-month period at the authors' facility. Of the 372 children, 142 children (38%) first received medical care elsewhere; these are the subjects of this study. Before being seen at the authors' institution, 27 children (19%) had a problem in treatment or diagnosis and 18 (13%) had a delay in diagnosis or treatment of greater than 48 hours. Problems in diagnosis included five children with unrecognized open fractures, four of whom did not receive antibiotics; six children with missed SCFE, five of whom were not made non-weight-bearing; and six missed closed fractures. Delay in treatment occurred for 15 fractures, with a mean delay of >7 days until surgical treatment. Insurance status and primary language of the family were not associated with problems or delays in treatment. Overall, 32% of children undergoing time-sensitive orthopaedic surgery at a tertiary pediatric center had problems or delays in the medical care they received before transfer. 相似文献
73.
Dalley JW Chudasama Y Theobald DE Pettifer CL Fletcher CM Robbins TW 《Psychopharmacology》2002,160(4):425-433
RATIONALE: Drug-paired stimuli elicit drug craving and relapse in addicts and drug-seeking behavior in rats. The functional integrity of the basolateral amygdala (BLA) is necessary for reinstatement of cocaine-seeking behavior elicited by cocaine-conditioned stimuli, but not by cocaine itself. It is unclear, however, whether the BLA plays a similar role in reinstatement of heroin-seeking behavior. OBJECTIVES: To this end, we examined the effects of tetrodotoxin (TTX)-induced inactivation of the BLA on conditioned and heroin-primed reinstatement of extinguished heroin-seeking behavior. METHODS: Rats were trained to press a lever for IV infusions of heroin (maintenance dose of 25 microg/infusion) paired with presentations of a light-tone stimulus complex during daily 3-h sessions. Responding was then allowed to extinguish prior to reinstatement testing. Reinstatement of extinguished heroin-seeking behavior (i.e. lever pressing in the absence of heroin reinforcement) was measured in the presence of response-contingent presentation of the heroin-paired stimulus complex alone and then following TTX (5 ng/0.5 microl per side) or vehicle infused into the BLA. In a separate group of rats, reinstatement was measured after saline injection (SC) and then following heroin priming (0.25 mg/kg, SC) with TTX or vehicle infused into the BLA. RESULTS: Both response contingent presentation of the stimulus complex and heroin priming significantly reinstated extinguished heroin-seeking behavior, and BLA inactivation abolished the ability of the heroin-paired stimuli and of heroin priming to reinstate responding. CONCLUSIONS: These findings suggests that the BLA is a critical component of the neural circuitry that mediates conditioned and heroin-induced reinstatement of heroin-seeking behavior. Furthermore, different neural substrates may mediate drug-primed relapse to cocaine versus heroin-seeking behavior. 相似文献
74.
Mechanisms of apoptosis induced by purine nucleosides in astrocytes 总被引:16,自引:0,他引:16
Di Iorio P Kleywegt S Ciccarelli R Traversa U Andrew CM Crocker CE Werstiuk ES Rathbone MP 《Glia》2002,38(3):179-190
Astrocytes release adenine-based and guanine-based purines under physiological and, particularly, pathological conditions. Thus, the aim of this study was to determine if adenosine induced apoptosis in cultured rat astrocytes. Further, if guanosine, which increases the extracellular concentration of adenosine, also induced apoptosis determined using the TUNEL and Annexin V assays. Adenosine induced apoptosis in a concentration-dependent manner up to 100 microM. Inosine, hypoxanthine, guanine, and guanosine did not. Guanosine or adenosine (100 microM) added to the culture medium was metabolized, with 35% or 15%, respectively, remaining after 2-3 h. Guanosine evoked the extracellular accumulation of adenosine, and particularly of adenine-based nucleotides. Cotreatment with EHNA and guanosine increased the extracellular accumulation of adenosine and induced apoptosis. Inhibition of the nucleoside transporters using NBTI (100 microM) or propentophylline (100 microM) significantly decreased but did not abolish the apoptosis induced by guanosine + EHNA or adenosine + EHNA, respectively. Apoptosis produced by either guanosine + EHNA or adenosine + EHNA was unaffected by A(1) or A(2) adenosine receptor antagonists, but was significantly reduced by MRS 1523, a selective A(3) adenosine receptor antagonist. Adenosine + EHNA, not guanosine + EHNA, significantly increased the intracellular concentration of S-adenosyl-L-homocysteine (SAH) and greatly reduced the ratio of S-adenosyl-L-methioine to SAH, which is associated with apoptosis. These data demonstrate that adenosine mediates apoptosis of astrocytes both, via activation of A(3) adenosine receptors and by modulating SAH hydrolase activity. Guanosine induces apoptosis by accumulating extracellular adenosine, which then acts solely via A(3) adenosine receptors. 相似文献
75.
Candice Contet Claire Gavériaux-Ruff Audrey Matifas Claudia Caradec Marie-France Champy Brigitte L Kieffer 《Neuropsychopharmacology》2006,31(8):1733-1744
Exposure to stress triggers hormonal and behavioral responses. It has been shown that the endogenous opioid system plays a role in some physiological reactions to stress. The opioid system was described to mediate analgesia induced by mild stressors and to modulate the activation of the hypothalamic-pituitary-adrenal axis. Our study assessed the contribution of opioid receptors in stress-induced analgesia and adrenocorticotropic hormone (ACTH) and corticosterone release by a genetic approach. We performed a parallel analysis of mice deficient in mu, delta, or kappa opioid receptors, as well as of triple opioid receptor knockout mice, following exposure to a mild stress (3-min swim at 32 degrees C). In wild-type mice, stress elicited an increase in jumping latency on the hot plate, which was influenced by gender and genetic background. This analgesic response was reversed both by naloxone and by the triple mutation, and decreased in mu and delta opioid receptor knockout females. In wild-type females, stress also delayed front- and hindpaw behaviors in the hot plate test and increased tail-flick latency in the tail immersion test. Opioid receptor deletion however did not affect these stress responses. In addition, stress produced an increase in ACTH and corticosterone plasma levels. This endocrine response remained unchanged in all mutant strains. Therefore our data indicate that, under our stress conditions, the endogenous opioid system is recruited to produce some analgesia whereas it does not influence hypothalamic-pituitary-adrenal axis activity. This implies that brain circuits mediating analgesic and hormonal responses to stress can be dissociated. 相似文献
76.
BACKGROUND AND OBJECTIVE: To determine methods to assess the success of blinding in randomized controlled trials (RCTs). METHODS: We searched MEDLINE, the Cochrane Controlled Trials Register, and the Cochrane Method Register and performed a manual search to target studies that attempt to assess blinding and describe the methods used in those studies. RESULTS: A total of 90 reports were selected. Reports assessed the success of blinding participants (n = 58), care providers (n = 36), and outcome assessors (n = 15). Of the 58 reports assessing the success of blinding participants, 54 (93%) reported asking participants to guess their treatment assignment. There was no consistency in timing of assessment (e.g., once at the end of the trial, 57%, or several times during the trial, 26%) or modalities of answering (e.g., "do not know" answers, 43%, or participants forced to guess, 31%). A statistical analysis was performed in 57% of reports. The statistical analysis mainly compared the proportion of correct guesses to those produced by chance (32%) or checked for a relation between participants' guesses and treatment assignment (23%). CONCLUSIONS: Methods of assessing the success of blinding, analysis and reporting the results were inconsistent and questionable. 相似文献
77.
Grounded theory and participatory action research methods are distinct approaches to qualitative inquiry. Although grounded theory has been conceptualized in constructivist terms, it has elements of positivist thinking with an image of neutral search for objective truth through rigorous data collection and analysis. Participatory action research is based on a critique of this image and calls for more inclusive research processes. It questions the possibility of objective social sciences and aspires to engage people actively in all stages of generating knowledge. The authors applied both approaches in a project designed to explore the experiences of female survivors of childhood sexual abuse with physical therapy and subsequently develop a handbook on sensitive practice for clinicians that takes into consideration the needs and perspectives of these clients. Building on this experience, they argue that the integration of grounded theory and participatory action research can empower clients to inform professional practice. 相似文献
78.
A rat model of preeclampsia 总被引:1,自引:0,他引:1
Ianosi-Irimie M Vu HV Whitbred JM Pridjian CA Nadig JD Williams MY Wrenn DC Pridjian G Puschett JB 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2005,27(8):605-617
Preeclampsia/eclampsia is a disorder of human pregnancy that continues to exact significant maternal morbidity and mortality and fetal wastage. Therapy of these disorders has not changed in over 50 years and there are no proven preventive measures. We describe a model of the development of a syndrome in the pregnant rat that resembles preeclampsia, which results from the imposition of excessive volume expansion early in gestation. We administered desoxycorticosterone acetate (DOCA) to pregnant animals whose drinking water had been replaced with saline. We compared the results obtained in these animals with those resulting from the study of control, virgin animals, virgin animals receiving DOCA and saline, and normal pregnant (NP) animals. The virgin animals given DOCA and saline did not become hypertensive. The experimental paradigm in the DOCA plus saline pregnant (PDS) animals provides many of the phenotypic characteristics of the human disorder including the development of hypertension, proteinuria, and intrauterine growth restriction. In addition, the mean blood nitrite/nitrate concentration was reduced in the PDS rats compared with their NP counterparts. We propose that this model may prove to be useful in the study of the human condition. 相似文献
79.
80.
Yano EM Asch SM Phillips B Anaya H Bowman C Chang S Bozzette S 《Military medicine》2005,170(11):952-959
OBJECTIVE: As the largest provider of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome health care services, the Department of Veterans Affairs (VA) has launched a national quality improvement program. As a first step, an assessment of how care for veterans with HIV/acquired immunodeficiency syndrome was organized was conducted. METHODS: Structured surveys were administered to senior HIV clinicians in 118 VA facilities, about local approaches to structuring, staffing, and delivering HIV health services. RESULTS: HIV care was chiefly delivered in special VA-based HIV clinics. HIV-related services were widely available on site, with non-VA referrals being more commonly needed to meet long-term care needs. Urban VA facilities had greater HIV caseloads, were more likely to have separate HIV clinics, and had greater access to HIV expertise, whereas rural practices focused on primary care-based models and tended to rely on off-site VA HIV experts. CONCLUSIONS: Understanding the organization and management of VA-based HIV services will help design systematic quality improvement efforts and meet the treatment needs of HIV-infected veterans. 相似文献