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21.
We have developed two protocols for inducing sustained, high-dose, alcohol-reinforced, oral alcohol drinking among some members of Macaca nemestrina social groups. Both protocols initially co-present alcohol and the entire daily food supply in a 2-h daily drinking session, with a later return to continuous availability of food. One protocol presents unflavored aqueous alcohol to partially food-deprived subjects; the other compares the drinking of flavored alcohol solutions with the drinking of equally palatable isocaloric non-alcohol solutions when monkeys are not deprived of food. Daily high-dose drinking developed in both protocols, with biomedical changes similar to those of early human alcoholism. Daily drinking to blood alcohol concentrations above 100 mg/dl was sustained in some animals after return to baseline food conditions, and this may have been related to social rank within the groups. Alcohol reinforced drinking of the flavored solutions. Although food deprivation initially produced heavier drinking, drinking with the two protocols was equivalent after return to baseline feeding conditions. These procedures open new opportunities for examining combined social and genetic influences on alcoholic-like drinking. 相似文献
22.
Gary Coleman Tom A. Gardiner Ariel Boutaud Alan W. Stitt 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(4):581-587
Background A recombinant form of the α2(IV)NC1 domain of type IV collagen has been shown to have potent anti-angiogenic activity although
this peptide has not been studied in the context of proliferative retinopathies. In the current investigation we examined
the potential for α2(IV)NC1 to regulate retinal microvascular endothelial cell function using a range of in vitro and in vivo
assay systems.
Materials and methods α2(IV)NC1 at concentrations between 0.1 and 1 μg/ml was added to retinal microvascular endothelial cells (RMECs) followed
by assessment of cell attachment, proliferation and survival. This agent was also tested within a novel in vitro three-dimensional
retinal angiogenesis assay and the number of angiogenic sprouts quantified. α2(IV)NC1 was also delivered intra-vitreally to
mice with oxygen-induced proliferative retinopathy (OIR) and neovascularisation evaluated in comparison with vehicle-treated
controls.
Results RMECs treated with α2(IV)NC1 (0.1, 0.5 and 1 μg/ml) showed delayed attachment at 3 h post-seeding, although this deficit had
been restored at the 6-h time point. BrdU assay of DNA replication revealed that confluent RMECs treated with α2(IV)NC1 showed
no measurable response in comparison with vehicle-treated controls. By contrast, proliferation of sub-confluent RMECs was
significantly reduced by α2(IV)NC1 at 0.5 μg/ml (P<0.01). α2(IV)NC1 also induced apoptosis in RMECs and inhibited angiogenesis of pre-existing retinal vascular networks in
vitro (P<0.001). Intra-vitreal injection of α2(IV)NC1 in the OIR model significantly inhibited pre-retinal neovascularisation compared
with vehicle-treated controls (P<0.001).
Conclusion α2(IV)NC1 inhibits angiogenesis in the retinal microvasculature. This recombinant protein has potential for the treatment
of neovascularisation in proliferative retinopathies.
BioStratum Inc. did not sponsor this research in any way. None of the authors are paid consultants with this company. 相似文献
23.
24.
Margaret Hogg Maxine Braithwaite Michael Bailey Tom Kotsimbos John W Wilson 《Journal of cystic fibrosis》2007,6(3):223-227
With increasing numbers of cystic fibrosis (CF) patients surviving to adulthood, issues related to vocation inevitably arise and warrant specific attention. We examined the percentage of participants with CF currently working and explored risk factors for work disability among adults with CF. METHOD: We recruited 50 consecutive patients from an adult cystic fibrosis service. Demographic, employment history, illness severity indicators and CF-attributed work disability factors were evaluated. Demographic risk factors for work disability using the illness severity measures of FEV(1), S-K score, CRDQ, and recent hospitalisation as independent variables were determined. RESULTS: Factorial analysis of a disability index (DI) indicated no dependency on FEV(1) or S-K score, but dependency on quality of life indices (p<0.05), age (p<0.05) and hospital admission rate (p<0.05). Hours worked per week were dependent on quality of life (p<0.01) (mastery of disease domain), fewer hospital admissions (p<0.01) and age (p<0.05). Sixty-eight percent of the sample reported that CF resulted in significant impediments to employment. However, few had sought vocational guidance (6%). CONCLUSION: Determinants of workforce participation shows that hours worked and perceived disability are more dependent on mastery of disease, age, and time in hospital, than on clinical severity scores. Health professionals may assist productivity through career counselling or tailored programs. 相似文献
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27.
Scott D Simon Erik P Castle Robert G Ferrigni Paul E Andrews 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(2):205-207
PURPOSE: To determine whether a routine postoperative chest x-ray is required following uneventful laparoscopic nephrectomy to rule out pneumothorax. METHODS: From June 1999 to May 2003, 308 laparoscopic nephrectomy cases were performed by 5 different surgeons. This consisted of 121 radical nephrectomies, 106 donor nephrectomies, 29 simple nephrectomies, 29 partial nephrectomies, and 23 nephroureterectomies. Of the 308 procedures, 186 postoperative chest x-ray s were obtained in the recovery room: 183 routinely and 3 for known intraoperative diaphragmatic injuries. Routine chest x-rays were not obtained in 122 cases due to the individual surgeon's preference. Of these 122 patients, 15 underwent chest x-ray performed while hospitalized secondary to pulmonary issues or fever. RESULTS: Of the 308 cases, 4 pneumothoraces were identified on chest x-ray. Three were identified in the patients who had intraoperative identification of diaphragmatic injury. The fourth pneumothorax was identified in a patient who did not have a routine postoperative chest x-ray but did have a chest x-ray obtained due to postoperative shoulder pain. The pneumothorax in this patient resolved spontaneously. No incidental findings existed of pneumothorax in any patient who underwent routine postoperative chest x-ray. CONCLUSION: In our series, a pneumothorax was identified either intraoperatively or based on postoperative clinical findings. None of the 183 routine postoperative chest x-rays changed patient management. Routine postoperative chest x-ray is not necessary in uncomplicated laparoscopic nephrectomy. 相似文献
28.
29.
Emma L Wignall Jon M Dickson Paul Vaughan Tom F D Farrow Iain D Wilkinson Michael D Hunter Peter W R Woodruff 《Neuropsychopharmacology》2004,56(11):832-836
BACKGROUND: Previous structural magnetic resonance (MR) research in patients with posttraumatic stress disorder (PTSD) has found smaller hippocampal volumes in patients compared with control subjects. These studies have mostly involved subjects who have had PTSD for a number of years, such as war veterans or adult survivors of childhood abuse. Patients with recent-onset PTSD have rarely been investigated. To our knowledge only one other study has investigated such a group. The aim of this study was to compare hippocampal volumes of patients with recent onset PTSD and nontrauma-exposed control subjects. METHODS: Fifteen patients with PTSD, recruited from an accident and emergency department, were compared with 11, non-trauma-exposed, healthy control subjects. Patients underwent a structural MR scan soon after trauma (mean time = 158 +/- 41 days). Entire brain volumes, voxel size 1 x 1 x 1 mm, were acquired for each subject. Point counting and stereology were used to measure the hippocampal and amygdala volume of each subject. RESULTS: Right-sided hippocampal volume was significantly smaller in PTSD patients than control subjects after controlling for effects of whole brain volume and age. Neither left nor total hippocampal volume were significantly smaller in the PTSD group after correction. Whole brain volume was also found to be significantly smaller in patients. There were no differences in amygdala or white matter volumes between patients and control subjects. CONCLUSIONS: This result replicates previous findings of smaller hippocampal volumes in PTSD patients, but in an underinvestigated population, suggesting that either smaller hippocampal volume is a predisposing factor in the development of PTSD or that damage occurs within months of trauma, rather than a number of years. Either of these two hypotheses have significant implications for the treatment of PTSD. For instance, if it could be shown that screening for hippocampal volume may, in some cases, predict those likely to develop clinical PTSD. 相似文献
30.
A portable ultrasound unit with a 3.5-MHz probe allows accurate imaging of both cerebral hemispheres and partial imaging of the posterior fossa through unilateral exploratory burr holes or a craniotomy. In patients with clinical signs of transtentorial herniation after severe head injury, this unilateral technique can detect extraaxial and intraparenchymal mass lesions more accurately than is possible with bilateral exploratory burr holes. 相似文献