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81.
82.
The expression of parvalbumin-like immunoreactivity (PV-LIR) was examined in the mystacial representation within the primary somatosensory cortex (SI) of postnatal day 21 and adult rabbits. PV-LIR was expressed in a prominent vibrissa-like array of patches in layer IV despite the fact that barrels were indistinct in the cytoarchitecture. Each patch consisted of dense terminal-like PV-LIR and a preferential concentration of intensely labeled stellate neurons. Layer V contained scattered small and large intensely labeled basket cells. Layer Vb had a distinct layer of lightly labeled large pyramidal cells that received labeled basket cell terminations. Upper layer VI also contained patches of terminal-like PV-LIR that were in register with the overlying vibrissae pattern. These patches also contained a preferential distribution of labeled non-pyramidal cells as well as modified pyramidal cells. These results suggest that PV-LIR in rabbits delineates cortical modules composed of thalamorcotical afferents and inhibitory local circuits in the absence of a distinct barrel cytoarchitecure. In contrast, prior studies of rat SI cortex have revealed a distinct barrel cytoarchitecture but a uniform distribution of PV-LIR. The differences in PV-LIR between rodents and lagomorphs within the vibrissae representation in SI may be related to species differences in thalamic and local cortical circuits devoted to the whisker sense. 相似文献
83.
D Evison R F R Brown P Rice 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(10):1087-1093
The chemical warfare agent, sulphur mustard (SM), is a potent blistering agent in man. Skin exposure can produce partial-thickness burns which take up to three months to heal. The aim of this study was to investigate the use of early laser ablation as a means of accelerating this exceptionally slow rate of healing. Four circular partial-thickness SM burns were induced on the dorsum of nine large white pigs (under general anaesthesia). At 72 h post-exposure, three burns per animal were ablated with a single pass of an UltraPulse 5000C CO(2) laser, at a fluence of 5-6 J cm(-2). All the burns were dressed with silver sulphadiazine and a semi-occlusive dressing. At one, two and three weeks post-surgery three animals were culled and all lesions excised for histological analysis. Burn depth was confirmed and measurements of the radii of regenerative epithelium were performed allowing the area of the zone of re-epithelialisation in each lesion to be calculated. Laser-treated lesions showed a significant increase (350%) in healing rates compared to controls (p<0.005). At two weeks, the laser-treated sites were 95% healed in comparison with control sites (28% healed). These data suggest that laser ablation may be effective in the treatment of partial-thickness SM-induced skin injury. 相似文献
84.
IL-12 and IL-23: master regulators of innate and adaptive immunity 总被引:27,自引:0,他引:27
Claire L. Langrish Brent S. McKenzie Nicholas J. Wilson Rene de Waal Malefyt Robert A. Kastelein Daniel J. Cua † 《Immunological reviews》2004,202(1):96-105
Summary: Initiation of an effective immune response requires close interactions between innate and adaptive immunity. Recent advances in the field of cytokine biology have led to an increased understanding of how myeloid cell‐derived factors regulate the immune system to protect the host from infections and prevent tumor development. In this review, we focus on the function of interleukin (IL)‐23, a new member of the IL‐12 family of regulatory cytokines produced by activated macrophages and dendritic cells. We propose that IL‐12 and IL‐23 promote two distinct immunological pathways that have separate but complementary functions. IL‐12 is required for antimicrobial responses to intracellular pathogens, whereas IL‐23 is likely to be important for the recruitment and activation of a range of inflammatory cells that is required for the induction of chronic inflammation and granuloma formation. These two cytokines work in concert to regulate cellular immune responses critical for host defense and tumor suppression. 相似文献
85.
Alex W Wilson Stephen J Medhurst Claire I Dixon Nick C Bontoft Lisa A Winyard Kim T Brackenborough Jorge De Alba Christopher J Clarke Martin J Gunthorpe Gareth A Hicks Chas Bountra Daniel S McQueen Iain P Chessell 《European Journal of Pain》2006,10(6):537-549
Clinically, inflammatory pain is far more persistent than that typically modelled pre-clinically, with the majority of animal models focussing on short-term effects of the inflammatory pain response. The large attrition rate of compounds in the clinic which show pre-clinical efficacy suggests the need for novel models of, or approaches to, chronic inflammatory pain if novel mechanisms are to make it to the market. A model in which a more chronic inflammatory hypersensitivity phenotype is profiled may allow for a more clinically predictive tool. The aims of these studies were to characterise and validate a chronic model of inflammatory pain. We have shown that injection of a large volume of adjuvant to the intra-articular space of the rat knee results in a prolonged inflammatory pain response, compared to the response in an acute adjuvant model. Additionally, this model also results in a hypersensitive state in the presence and absence of inflammation. A range of clinically effective analgesics demonstrate activity in this chronic model, including morphine (3mg/kg, t.i.d.), dexamethasone (1mg/kg, b.i.d.), ibuprofen (30mg/kg, t.i.d.), etoricoxib (5mg/kg, b.i.d.) and rofecoxib (0.3-10mg/kg, b.i.d.). A further aim was to exemplify the utility of this chronic model over the more acute intra-plantar adjuvant model using two novel therapeutic approaches; NR2B selective NMDA receptor antagonism and iNOS inhibition. Our data shows that different effects were observed with these therapies when comparing the acute model with the model of chronic inflammatory joint pain. These data suggest that the chronic model may be more relevant to identifying mechanisms for the treatment of chronic inflammatory pain states in the clinic. 相似文献
86.
Kazumasa Fujitani Jaffer A. Ajani Christopher H. Crane Barry W. Feig Peter W. Pisters Nora Janjan Garrett L. Walsh Stephen G. Swisher Ara A. Vaporciyan David Rice Angela Welch Jackie Baker Josephine Faust Paul F. Mansfield MD 《Annals of surgical oncology》2007,14(4):1305-1311
Background Significant tumor downstaging has been achieved in patients with localized gastric or gastroesophageal adenocarcinoma by induction
chemotherapy and preoperative chemoradiotherapy (CTX–CTXRT). However, the influence of CTX–CTXRT on operative morbidity and
mortality has not yet been clarified. The aim of the present study was to document the frequency and nature of morbidity and
mortality after surgery combined with CTX–CTXRT, and identify factors predictive of postoperative complications in patients
with localized gastric or gastroesophageal adenocarcinoma.
Methods A prospectively collected database on 71 consecutive patients who underwent CTX–CTXRT at M.D. Anderson Cancer Center between
January 1997 and August 2004 was reviewed. Postoperative morbidity and mortality were investigated, and risk factors for overall
complications were identified by multivariate logistic regression analysis.
Results Overall morbidity and mortality rates were 38.0% (27 patients) and 2.8% (2 patients), respectively. Age greater than 60 years
[relative risk 11.3 (95% confidence interval 2.50–50.6)] and body mass index (BMI) of 26 kg/m2 or above [relative risk 4.08 (95% confidence interval 1.08–15.4)] were significant risk factors for overall complications.
Conclusions CTX–CTXRT can be performed safely with an acceptable operative morbidity and a low operative mortality rate in patients with
gastric or gastroesophageal cancer, with careful consideration of added risk associated with age and obesity. 相似文献
87.
Background: The slitlamp can be used to estimate the anterior chamber depth (ACD). The length of a slit object is increased until the corneal and iris/lens images appear to just touch. Multiplying the just‐touching‐slit‐length (JTSL) by a conversion factor gives an estimate of the ACD as measured by ultrasonography. The purpose of this study was to determine if central corneal thickness (CCT) affects the accuracy of this technique. Methods: The ACD of 50 subjects was measured by A‐scan ultrasonography and estimated by the slitlamp technique. CCT was measured by ultrasonic pachometry. The refractive error was determined subjectively. Results: The average ultrasonographic ACD for all subjects was 3.32 ± 0.65 mm. The average JTSL was 2.46 ± 0.38 mm. The conversion ratio between the ultrasonographic ACD and the average JTSL was 1.35. The predicted ACD using the regression equation of JTSL on the ultrasound anterior chamber depth (USACD) was 3.32 ± 0.54 mm. The corresponding value using the regression equation of JTSL and CCT on USACD was exactly the same, that is, 3.32 ± 0.54 mm. Conclusion: Incorporation of CCT into a regression equation does not improve the accuracy of the Smith technique. 相似文献
88.
89.
Changes in the design of hospital wards have usually been determined by architects and members of the nursing and medical professions, the views and preferences of patients have seldom been sought directly The Hospital Anxiety and Depression scale and the Disturbance Due to Hospital Noise questionnaire were administered to 64 female patients on bay and Nightingale wards together with a questionnaire designed for this study Perceptions of social and physical factors of ward design were examined, and their relationship to psychological well-being and sleep patterns The results show that the bay ward seemed to offer a more favourable environment for patients but some of the disadvantages of bay wards are balanced by better staffing levels and better and more modern facilities Visibility to nurses was lower on the bay ward The Nightingale ward was perceived as significantly noisier than the bay ward and noise levels were significantly correlated to anxiety scores Paradoxically the increase in noise levels appeared to improve the perceived level of privacy on the Nightingale ward Seventy-five per cent of patients were found to prefer the bay ward design, and since neither design appears to have major disadvantages their continued introduction should be encouraged However, recommendations are made concerning the optimizing of patients' well-being within the bay ward setting 相似文献
90.