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991.
Ccile Rousseau Ghayda Hassan Toby Measham Nicolas Moreau Myrna Lashley Thelma Castro Caminee Blake Georges McKenzie 《Health & place》2009,15(3):751-760
Caribbean and Filipino immigrant families in Canada have much in common: the women have often immigrated as domestic workers, first-generation children may be separated from their parents for long periods, and they must deal with negative stereotypes of their ethnic group. This transcultural study looks at the associations between family relations and adolescents’ perceptions of both their own group and the host society, and analyzes how these affect their mental health. The results suggest that family cohesion plays a key role in shaping adolescents’ perceptions of racism in the host country and in promoting a positive appraisal of their own community, thus highlighting the need for a systemic understanding of family and intergroup relations. 相似文献
992.
A series of fluorinated 1,2,4‐triazolo[1,5‐a]pyrimidine‐6‐carboxylic acid derivatives was designed and synthesized as fluoroquinolone analogues. The synthesized compounds were screened against Mycobacterium tuberculosis H37Rv strain at 6.25 μg/mL concentration. Compound 4 , the 7‐oxo‐2‐(trifluoromethyl)‐4,7‐dihydro‐1,2,4‐triazolo[5,1‐a]pyrimidine‐6‐carboxylic acid was found to be a very potent inhibitor, being able to inhibit 92% growth of M. tuberculosis H37Rv at 6.25 μg/mL concentration. At the same time, it proofed to be nontoxic to mammalian cells (IC50 > 62.5 μg/mL in VERO cells). 相似文献
993.
Jafarnejad A Bathaie SZ Nakhjavani M Hassan MZ 《The Journal of pharmacology and experimental therapeutics》2008,324(2):850-857
Diabetes mellitus has been classified as a conformational disease because of changes induced in the structure and function of proteins due to hyperglycemia. In this study, we investigated the effect of high-dose and long-term use of acetyl salicylic acid (ASA) on the streptozotocin-induced diabetic rats as a model of type I diabetes, with consideration on the structure and/or function of proteins. The N-[methylnitrosocarbamoyl]-d-glucosamine (streptozotocin)-induced diabetic rats together with the normal rats were studied for 5 months with and without receiving 100 mg/kg ASA in drinking water. All rats were investigated from different aspects such as heat shock protein (HSP) 70 level, serum glucose and insulin concentration, advanced glycated end product (AGE) and glycated hemoglobin (HbA1c) formation, lipid profile, high-density lipoprotein (HDL) functionality (paraoxonase1 and lecithin cholesterol acyltransferase activities), and the antioxidant system. In addition, the in vitro effect of ASA on the structure of albumin as a model protein was studied in the presence of glucose by spectroscopic techniques such as fluorometry and circular dichroism. The results show that ASA therapy causes a decrease in the glucose level and AGE and HbA1c formation, improves the lipid profile, HDL functionality, and the antioxidant capacity, induces serum HSP70, and overall decreases mortality of diabetic rats in comparison with the group without treatment. The conformation of glycated bovine serum albumin is different from the native form, and ASA retains the conformation of this protein similar to the native. The improving effect of ASA on diabetic rats is mostly due to its role as a chemopreventive agent in the structural conservation and protection of proteins involved in diabetes pathogenesis. 相似文献
994.
Geronikaki A Vicini P Dabarakis N Lagunin A Poroikov V Dearden J Modarresi H Hewitt M Theophilidis G 《European journal of medicinal chemistry》2009,44(2):473-481
On the basis of computer prediction of biological activity by PASS and toxicity by DEREK, the most promising 32-alkylaminoacyl derivatives of 3-aminobenzo[d]isothiazole were selected for possible local anaesthetic action. This action was evaluated using an in vitro preparation of the isolated sciatic nerve of the rat and compared with lidocaine which was used as a reference compound. QSAR studies showed that the polarizability, polarity and molecular shape of molecules have a positive influence on their local anaesthetic activity, while contributions of aromatic CH and singly bonded nitrogen are negative. Since the estimated PASS probabilities to find local anaesthetic activity in the most active compounds are less than 50%, these compounds may be considered to be possible NCEs. 相似文献
995.
996.
Background Until recently, laparoscopic ultrasound (LUS)-guided biopsy has been difficult with the available probes on the market. This
study aimed to present a new laparoscopic ultrasound probe (Hitachi, EUP-OL531) for guided biopsy and describe its impact
on the clinical outcome for patients with upper gastrointestinal (UGI) cancer.
Methods Patients referred with confirmed UGI cancer from June 2003 to December 2006 were included in the study. After a standard workup
including computed tomography, endoscopic ultrasound, and ultrasound of the neck, operable patients underwent LUS with or
without fine-needle aspiration (FNA).
Results From a total of 175 patients, 19 (11%) underwent LUS-guided FNA after a significant lesion was found. The LUS-guided FNA confirmed
distant metastasis in 14 of the 19 patients and changed the clinical management for these 14 patients (8%). There were no
adverse events due to LUS or LUS-guided FNA.
Conclusion The current results with the new LUS probe for guided FNA are encouraging in terms of its diagnostic ability, safety, and
ease of use. 相似文献
997.
Recent evidence suggests substantial overlap between mood and anxiety disorders, both in clinical presentation and associated features. A theoretical framework to account for this overlap focuses on negative affectivity, defined as the disposition to experience negative emotional states, including fear, sadness, and guilt. This model has been successful in explaining the co-occurrence of depressive and anxiety disorders in humans. As a next step, development of an animal model focused on both depression- and anxiety-relevant behaviors may advance understanding of depression-anxiety symptom overlap, relations of these disorders with associated medical conditions and responses to treatment. This study was designed to investigate inducible and quantifiable depression- and anxiety-like behaviors in prairie voles (Microtus ochrogaster). Adult, female prairie voles were exposed to 4 weeks of social pairing (control) or isolation, an established stressor for socially monogamous mammals (including humans). Operational measures of depression (sucrose intake and behaviors in the forced swim test), anxiety (behaviors in the elevated plus maze), and aggression (responses to an unrelated prairie vole pup) were investigated. Social isolation induced a progressive decline in sucrose intake and increased immobility time during the forced swim test. Social isolation also decreased the amount of time spent in the open arms of the elevated plus maze, and increased pup-directed attack behavior. The current findings suggest that isolation induces behaviors reflecting elevated negative affect. These results may provide a foundation for creating a rodent model to examine the mechanisms underlying comorbid mood and anxiety disorders. 相似文献
998.
Mas JL Trinquart L Leys D Albucher JF Rousseau H Viguier A Bossavy JP Denis B Piquet P Garnier P Viader F Touzé E Julia P Giroud M Krause D Hosseini H Becquemin JP Hinzelin G Houdart E Hénon H Neau JP Bracard S Onnient Y Padovani R Chatellier G;EVA-S investigators 《Lancet neurology》2008,7(10):885-892
999.
Developing accessible biomarkers of neurotoxic effects which are readily applicable to human populations poses a challenge for neurotoxicology. In the past, the neurotoxic organometal trimethyltin (TMT) has been used as a denervation tool to validate the enhanced expression of GFAP as a biomarker of astrogliosis and neurotoxicity resulting from chemical exposures. In the present study, TMT was used to assess the detection of serum autoantibodies as biomarkers of neurotoxicity. Previous studies in both human and animals have demonstrated the presence of serum autoantibodies to neurotypic [e.g., neurofilament triplet (NF)] and gliotypic proteins [myelin basic protein (MBP) and glial fibrillary acidic protein (GFAP)] as a peripheral marker of neurodegeneration that may be applicable to humans and experimental studies. Male Long-Evans rats (45 days of age) were administered either TMT (8 mg/kg; s) or an equal volume of sterile 0.9% saline. At 1, 2, and 3 weeks post-administration, serum was collected, and rats were sacrificed for the collection of brains. Serum autoantibodies (both IgM and IgG isotypes) to NF68, NF160, NF200, MBP, and GFAP were assayed using an ELISA. Saline only rats did not have detectable levels of autoantibodies. Only sera from TMT-exposed rats had detectable titers of autoantibodies to NFs with IgG predominating starting week 2. Anti-NF68 titers were highest compared to NF160, or NF200. Autoantibodies to MBP and GFAP also were detected; however, there was no significant increase in their titers until week 3. Hippocampal GFAP, detected at these time points, was significantly (p<0.05) higher than in control brains, indicating the induction of astrogliosis as confirmed by immunostaining of brain sections. The detection of anti-NFs, as indicative of neuronal insult, was consistent with loss of hippocampal neurons in CA3 and CA1. Our results suggest that the detection of autoantibodies to neurotypic and gliotypic proteins may be used as peripheral biomarkers to reveal evidence of nervous system neurotoxicity. 相似文献
1000.
Hassan I You YN Cima RR Larson DW Dozois EJ Barnes SA Pemberton JH 《Surgical endoscopy》2008,22(3):739-743
Introduction Laparoscopic assisted (LA) colectomy has significant patient benefits but is technically challenging. Hand-assisted laparoscopic
surgery (HALS) allows tactile feedback because the surgeon’s hand assists in retraction and dissection. This may decrease
the technical difficulty and shorten the learning curve associated with performing laparoscopic colectomy. We investigated
the patient selection and short-term clinical outcomes of HALS and LA since the introduction of HALS to our minimally invasive
colorectal practice.
Methods Prospectively collected data on 258 patients undergoing HALS (n = 109) or LA colectomy (n = 149) during a calendar year (2004) were analyzed. Patient and disease characteristics, operative parameters, and perioperative
outcomes were compared.
Results HALS patients were similar to LA patients in age (51 vs. 54 yrs), gender (56 vs. 52% male), body mass index (26 vs. 26 kg/m2),
comorbidities (84 vs. 85% with one or more), and diagnosis (83 vs. 80% benign), but differed in incidence of previous surgery
(49 vs. 30%; P = 0.008). A significantly greater proportion of HALS patients underwent complex procedures and extensive resections. Conversion
rates (15 vs. 11%, P = 0.44), intraoperative complications (4 vs. 1%, P = 0.17), 30-day morbidity (18 vs. 11%, P = 0.12) and surgical reinterventions (2 vs. 1%, P = 0.58) did not differ. Recovery measured by days to flatus was not different [mean (standard deviation) 3(2) vs. 3(2) days,
P = 0.26], however HALS patients had longer operative times [276(96) vs. 211(107) minutes P < 0.0001] and 1 day longer stay in hospital [6(3) vs. 5 (3) days, P = 0.0009)].
Conclusions Patients undergoing HALS underwent more-complex procedures than LA patients but retained the short-term benefits associated
with LA colectomy. HALS facilitates expansion of a minimally invasive colectomy practice to include more challenging procedures
while maintaining short-term patient benefits.
Presented at the 2007 Annual Meeting of the Society of American Gastrointestinal and Endoscopic Surgeons, Las Vegas, Nevada. 相似文献