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51.
《Journal of liposome research》2013,23(1):88-94
This blinded crossover study evaluated the efficacy and pain sensitivity evoked by a previously reported liposome-encapsulated mepivacaine formulation (). Thirty healthy volunteers received an intraoral injection (1.8?mL), at four different sessions, of the following formulations: 2% mepivacaine with 1:100,000 epinephrine (MVC2%EPI), 3% mepivacaine (MVC3%), and 2 and 3% liposome-encapsulated mepivacaine (MVC2%LUV and MVC3%LUV). Latency period and duration of anesthesia were assessed by an electrical pulp tester and injection discomfort by a visual analog scale (VAS). Data were analyzed with Tukey-Kramer and Friedman tests (P?<?0.05). No significant difference was found regarding latency period (in minutes) among the formulations (P?>?0.05). The duration of anesthesia after the injection of MVC3%LUV was higher than the one obtained after the infiltration of MVC2%LUV and of MVC3% (P?<?0.05). However, the duration of anesthesia obtained with MVC3% did not differ from the one obtained with MVC2%LUV (P?>?0.05). MVC3%LUV showed lower VAS median values than MVC2%EPI (P?<?0.05), and there were no significant differences among the others formulations. Liposome-encapsulated 3% mepivacaine showed longer duration of anesthesia, in comparison to the commercial formulation of MVC3%. MVC2%LUV was able to produce a similar duration of anesthesia as the 3% commercial formulation, despite the 50% decrease in the anesthetic concentration. Thus, the encapsulation of mepivacaine increased the duration of anesthesia and reduced the injection discomfort caused by vasoconstrictor-associated formulations in healthy volunteers. 相似文献
52.
《Chronobiology international》2013,30(5):759-765
We examined the well-known spontaneous discharge (SD) and lightevoked (PD) discharge of the crayfish caudal photoreceptor for the possible existence of a daily rhythm in spike frequency. To do this, we isolated the abdominal nerve cord in vitro and studied its discharge frequency in constant darkness. Single cosinor analysis revealed significant SD and PD circadian rhythms (P <. 05) with periods τ = 24.4h and 24.2h, respectively. These oscillations correspond to an endogenous circadian discharge of the caudal photoreceptor that is enhanced by light. The importance of this rhythm in the adaptive behavior of crayfish is discussed. (Chronobiology International, 18(5), 759–765, 2001) 相似文献
53.
《Chronobiology international》2013,30(5):425-433
The circadian rhythm of core body temperature is associated with widespread physiological effects. However, studies with other more practical temperature measures, such as wrist (WT) and proximal temperatures, are still scarce. The aim of this study was to investigate whether obesity is associated with differences in mean WT values or in its daily rhythmicity patterns. Daily patterns of cortisol, melatonin, and different metabolic syndrome (MetS) features were also analyzed in an attempt to clarify the potential association between chronodisruption and MetS. The study was conducted on 20 normal-weight women (age: 38?±?11 yrs and BMI: 22?±?2.6?kg/m2) and 50 obese women (age: 42?±?10 yrs and BMI: 33.5?±?3.2?kg/m2) (mean?±?SEM). Skin temperature was measured over a 3-day period every 10?min with the “Thermochron iButton.” Rhythmic parameters were obtained using an integrated package for time-series analysis, “Circadianware.” Obese women displayed significantly lower mean WT (34.1°C?±?0.3°C) with a more flattened 24-h pattern, a lower-quality rhythm, and a higher intraday variability (IV). Particularly interesting were the marked differences between obese and normal-weight women in the secondary WT peak in the postprandial period (second-harmonic power [P2]), considered as a marker of chronodisruption and of metabolic alterations. WT rhythmicity characteristics were related to MetS features, obesity-related proteins, and circadian markers, such as melatonin. In summary, obese women displayed a lower-quality WT daily rhythm with a more flattened pattern (particularly in the postprandial period) and increased IV, which suggests a greater fragmentation of the rest/activity rhythm compared to normal-weight women. These 24-h changes were associated with higher MetS risk. (Author correspondence: garaulet@um. es) 相似文献
54.
Thomas Silberfeld Lucie Bittner Cindy Fernández‐García Corinne Cruaud Florence Rousseau Bruno de Reviers Frederik Leliaert Claude E. Payri Olivier De Clerck 《Journal of phycology》2013,49(1):130-142
The brown algal genus Padina (Dictyotales, Phaeophyceae) is distributed worldwide in tropical and temperate seas. Global species diversity and distribution ranges, however, remain largely unknown. Species‐level diversity was reassessed using DNA‐based, algorithmic species delineation techniques based on cox3 and rbcL sequence data from 221 specimens collected worldwide. This resulted in estimates ranging from 39 to 61 putative species (ESUs), depending on the technique as well as the locus. We discuss the merits, potential pitfalls, and evolutionary and biogeographic significance of algorithmic species delineation. We unveil patterns whereby ESUs are in all but one case restricted to either the Atlantic or Indo‐Pacific Ocean. Within ocean basins we find evidence for the vast majority of ESUs to be confined to a single marine realm. Exceptions, whereby ESUs span up to three realms, are located in the Indo‐Pacific Ocean. Patterns of range‐restricted species likely arise by repeated founder events and subsequent peripatric speciation, hypothesized to dominate speciation mechanisms for coastal marine organisms in the Indo‐Pacific. Using a three‐gene (cox3, psaA and rbcL), relaxed molecular clock phylogenetic analysis we estimated divergence times, providing a historical framework to interpret biogeographic patterns. 相似文献
55.
Cynthia J. Tsay 《The Yale journal of biology and medicine》2013,86(2):245-254
Julius Wagner-Jauregg, a preeminent Austrian psychiatrist was awarded the Nobel
Prize in Medicine in 1927 for the development of malaria therapy for the
treatment of neurosyphilis, or general paresis of the insane. Despite being only
one of three psychiatrists to win a Nobel Prize, he has faded from public
consciousness and his name recognition pales in comparison to his contemporary
and fellow Austrian, Sigmund Freud. This paper explores his contributions to the
field of biological psychiatry and also touches upon reasons, such as the
growing bioethics movement, his controversial affiliation with the Nazi Party,
and the evolution of neurosyphilis, that explain why Wagner-Jauregg is not more
widely celebrated for his contributions to the field of psychiatry, even though
his malarial treatment could be considered the earliest triumph of biological
psychiatry over psychoanalysis. 相似文献
56.
Daniel R. Matute Alexandra Harris 《Evolution; international journal of organic evolution》2013,67(8):2451-2460
Drosophila yakuba and D. santomea are sister species that differ in their levels of abdominal pigmentation; D. yakuba shows heavily pigmented posterior abdominal segments in both sexes, whereas D. santomea lacks dark pigment anywhere on its body. Using naturally collected lines, we demonstrate the existence of altitudinal variation in abdominal pigmentation in D. yakuba but not in D. santomea. We use the variation in pigmentation within D. yakuba and two body‐color mutants in D. yakuba to elucidate selective advantage of differences in pigmentation. Our results indicate that although differences in abdominal pigmentation have no effect on desiccation resistance, lighter pigmentation confers ultraviolet radiation resistance in this pair of species. 相似文献
57.
医院绩效管理中存在倾向于刚性管理并热衷于惩罚方式的现象,其结果是无意中起了引导员工为逃避惩罚而隐瞒相关信息的作用,从而使医院员工不能共同分享与讨论各种经验教训,不利于医院进行持续质量改进。而有效预防与解决这一问题的主要策略是在绩效管理中进行人性化管理,并以柔性化操作处理那些不易进行刚性考核或易在刚性考核中产生消极后果的问题。 相似文献
58.
??????? 目的 探讨抗菌药物临床应用专项整治活动对综合医院住院患者抗菌药物使用强度的影响。方法 以限定日剂量(DDD)为单位,对某综合性医院在实施专项整治前、后住院患者抗菌药物使用强度(AUD)进行统计、分析。结果 专项整治活动降低了住院患者累计AUD值,大环内酯类等药物AUD明显下降,第二代、第三代和第四代头孢菌素和不同管理级别抗菌药物AUD均下降。但还存在用药集中、注射用头孢哌酮钠舒巴坦钠AUD下降不明显等问题。结论 专项整治有效降低了综合医院住院患者AUD,但与卫生行政部门标准仍存在差距,应进一步加强管理。 相似文献
59.
《Bioscience, biotechnology, and biochemistry》2013,77(12):3098-3101
Microfluid filters were fabricated, which possessed 2,100 cylindrical through-bores (φ40 μm) in 200 μm-thickness polymethylmethacrylate (PMMA) sheets (φ3 mm), by deep X-ray lithography using synchrotron radiation. To evaluate the microfluid filters as a device for an immunoassay, we bound the goat anti-mouse immunogloblin G (IgG) antibody to the surface of the filters, and set the filters between reaction vessels stacked vertically in a microreactor. An enzyme-linked immunosorbent assay (ELISA) of mouse IgG using the goat anti-mouse IgG/horseradish-peroxidase (HRP) conjugate indicated that mouse IgG could be quantitatively detected in the range of 0–100 ng/ml, demonstrating the applicability of vertical microfluidic operation to the immunoassay. 相似文献
60.
目的了解妇科恶性肿瘤术后患者阴道微生态的状况,探讨妇科恶性肿瘤术后阴道微生态评价的临床意义。方法选取100例妇科恶性肿瘤术后复查的患者,取阴道分泌物进行微生态评价,以同期30例绝经体检妇女作为对照。结果妇科恶性肿瘤术后阴道优势菌以乳酸杆菌为主的,占41%;菌群密集度多在+ + ~+ + +,占52%;菌群多样性多在+ + ~+ + +,44% ;PH^4.5,占35% ;VVC阳性率为4% ;阴道毛滴虫阳性率为7% ;BV阳性率为5% ;微生态失调的发生率占69%。结论(1)妇科恶性肿瘤术后,阴道微生态失调发生率明显增高;(2)妇科恶性肿瘤术后阴道微生态的失调与肿瘤的种类、恶性程度、手术范围、卵巢去留等无关,但术后时间越长,阴道微生态失调率越高;(3)评价妇科恶性肿瘤术后阴道微生态环境的状况,对预防与治疗术后生殖道感染具有重要指导意义。 相似文献