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941.
目的:探讨在大鼠乳腺癌骨转移诱导癌症疼痛的调控过程中Akt信号通路的作用。方法:将Wistar成模wistar大鼠随机分为Model组、Model+GSK690693组及Model+Saline组;Model组大鼠不进行鞘内注射,Model+GSK690693组及Model+Saline组大鼠,于手术后数天(post-cancer cell implantation day,PID)PID 13 d、14 d及21 d鞘内分别注入Akt特异抑制剂GSK690693、等量生理盐水组,分别于PID 0 d、7 d、14 d及21 d,观察大鼠痛相关行为学检查,PID 21 d取DRG行免疫印迹检查p-Akt表达。结果:在鞘内注射Akt特异性抑制剂GSK690693后,Model+GSK690693组大鼠的机械缩足反射阈值上升,自发性疼痛行为值及患侧DRG中p-Akt表达下降。在PID 14 d、21 d等不同时间节点,Model+GSK690693组大鼠的疼痛行为学与Model+Saline组大鼠、Model组大鼠经统计学比较有显著的统计学差异(P0.01);PID 21d Model+GSK690693组大鼠患侧DRG中p-Akt表达与Model组的比较有显著统计学意义(P0.01),与Model+Saline组比较有统计学意义(P0.05);结论:鞘内注射Akt特异性抑制剂GSK690693可抑制大鼠乳腺癌骨转移诱导的大鼠痛相关行为。  相似文献   
942.
目的:探讨平行侧入法硬膜外穿刺腰硬联合麻醉对剖宫产术后腰背痛的影响。方法:选择2014年10月至2016年9月在我院行剖宫产的产妇95例,将其随机分为两组。对照组45例,产妇接受平行直入法硬膜外穿刺腰硬联合麻醉,观察组50例产妇接受平行侧入法硬膜外穿刺麻醉。比较两组产妇术后宫缩、伤口、腰背疼痛VAS评分、术中穿刺情况、术后使用镇痛泵的有效按压次数及术后3 d、7 d、14 d和2个月后腰背疼痛的情况。结果:观察组产妇术后宫缩、伤口以及腰背疼痛评分、术后使用镇痛泵的有效按压次数均显著低于对照组(P0.05),且术中一次性穿刺成功率显著高于对照组(P0.05),且术后7 d、14 d以及2个月腰背痛的发生率显著低于对照组(P0.05)。结论:平行侧入穿刺法行腰硬联合麻醉可有效提高剖宫产产妇一次穿刺成功率,显著缓解产妇的术后疼痛,并降低术后腰背疼痛的发生率。  相似文献   
943.
Objective: To compare ethnic differences in visceral adipose tissue (VAT), assessed by computed tomography, and type 2 diabetes risk among 55‐ to 80‐year‐old Filipino, African‐American, and white women without known cardiovascular disease. Research Methods and Procedures: Subjects were participants in the Rancho Bernardo Study (n = 196), the Filipino Women's Health Study (n = 181), and the Health Assessment Study of African‐American Women (n = 193). Glucose and anthropometric measurements were assessed between 1995 and 2002. Results: African‐American women had significantly higher age‐adjusted BMI (29.7 kg/m2) and waist girth (88.1 cm) compared with Filipino (BMI, 25.5 kg/m2; waist girth, 81.9 cm) or white (BMI: 26.0 kg/m2; waist girth: 80.7 cm) women. However, VAT was significantly higher among Filipino (69.1 cm3) compared with white (62.3 cm3; p = 0.037) or African‐American (57.5 cm3, p < 0.001) women. VAT correlated better with BMI (r = 0.69) and waist (r = 0.77) in whites, compared with Filipino (r = 0.42; r = 0.59) or African‐American (r = 0.50; r = 0.56) women. Age‐adjusted type 2 diabetes prevalence was significantly higher in Filipinas (32.1%) than in white (5.8%) or African‐American (12.1%) women. Filipinas had higher type 2 diabetes risk compared with African Americans [adjusted odds ratio, 2.30; 95% confidence interval (CI), 1.09 to 4.86] or whites (adjusted odds ratio, 7.51; 95% CI, 2.51 to 22.5) after adjusting for age, VAT, exercise, education, and alcohol intake. Discussion: VAT was highest among Filipinas despite similar BMI and waist circumference as whites. BMI and waist circumference were weaker estimates of VAT in Filipino and African‐American women than in whites. Type 2 diabetes prevalence was highest among Filipino women at every level of VAT, but VAT did not explain their elevated type 2 diabetes risk.  相似文献   
944.
Objective: To evaluate the interplay among abdominal adipose tissue distribution, the cortisol axis, the autonomic nervous system, and insulin resistance. Research Methods and Procedures: Two age‐, sex‐, and BMI‐matched groups were studied. Fifteen subjects were first‐degree relatives of patients with type 2 diabetes (R), and 15 had no family history of diabetes (controls, C). A hyperinsulinemic euglycemic clamp, cortisol measurements, and analysis of heart rate variability (HRV) were performed. Computed tomography was performed in a subgroup (n = 9 + 9) to determine abdominal adipose tissue distribution. Results: R tended to be less insulin‐sensitive than C (M value 9.2 ± 1.0 vs 10.3 ± 0.7 mg/kg per minute, not significant). Stimulation with tetracosactin or corticotropin releasing hormone yielded lower peak serum cortisol levels in R (p = 0.03 and p = 0.06, respectively). The amount of visceral abdominal fat (VAT) tended to be greater in R. In all subjects, VAT was negatively correlated to insulin sensitivity (r = ?0.93, p < 0.001). There was a positive association between VAT and resting heart rate (r = 0.70, p = 0.003) and sympathetic/parasympathetic ratio in HRV assessment after tilt (r = 0.53, p = 0.03). Subcutaneous abdominal tissue was not associated with insulin sensitivity or any of the hormonal or HRV assessments. Discussion: Subjects genetically predisposed for type 2 diabetes had a tendency toward a larger amount of VAT and to lower insulin sensitivity compared with control subjects. The amount of visceral fat was strongly associated with insulin resistance and signs of a high ratio of sympathetic vs. parasympathetic reactivity. A large amount of visceral fat may act in concert with sympathetic/parasympathetic imbalance to promote the development of insulin resistance, and this may be partly independent of genetic background.  相似文献   
945.
Barton and Blanchard's report that multicomponent behavioral treatment fails to modify chronic daily headaches is discussed with reference to the effectiveness of behavioral and drug treatments for chronic tension-type headache, the distinction between chronic tension-type headache and chronic migraine, and the psychophysiology of episodic vs. persistent pain (K. A. Barton & E. B. Blanchard, 2001). It is suggested that the treatment of chronic daily headache can be improved through research on the benefits of combined behavioral and drug therapy, the psychophysiology of persistent pain, and methods of preventing episodic headaches from evolving to daily headaches.  相似文献   
946.
Human toxocariasis is a helminthozoonosis due to the migration of Toxocara species larvae through human organism. Humans become infected by ingesting either embryonated eggs from soil (geophagia, pica), dirty hands or raw vegetables, or larvae from undercooked giblets. The diagnosis relies upon sensitive immunological methods (ELISA or western-blot) which use Toxocara excretory-secretory antigens. Seroprevalence is high in developed countries, especially in rural areas, and also in some tropical islands. The clinical spectrum of the disease comprises four syndromes, namely visceral larva migrans, ocular larva migrans, and the more recently recognized "common" (in adults) and "covert" (in children) pictures. Therapy of ocular toxocariasis is primarily based upon corticosteroids use, when visceral larva migrans and few cases of common or covert toxocariasis can be treated by anthelmintics whose the most efficient appeared to be diethylcarbamazine. When diagnosed, all of these syndromes require thorough prevention of recontamination (especially by deworming pets) and sanitary education.  相似文献   
947.
Nerve growth factor induces P2X(3) expression in sensory neurons   总被引:3,自引:0,他引:3  
Glial cell line-derived neurotrophic factor (GDNF) and nerve growth factor (NGF) are neuroprotective for subpopulations of sensory neurons and thus are candidates for pain treatment. However, delivering these factors to damaged neurons will invariably result in undamaged systems also being treated, with possible consequences for sensory processing. In sensory neurons the purinergic receptor P2X(3) is found predominantly in GDNF-sensitive nociceptors. ATP signalling via the P2X(3) receptor may contribute to pathological pain, suggesting an important role for this receptor in regulating nociceptive function. We therefore investigated the effects of intrathecal GDNF or NGF on P2X(3) expression in adult rat spinal cord and dorsal root ganglia (DRG). In control spinal cords, P2X(3) expression was restricted to a narrow band of primary afferent terminals within inner lamina II (II(i)). Glial cell line-derived neurotrophic factor treatment increased P2X(3) immunoreactivity within lamina II(i) but not elsewhere in the cord. Nerve growth factor treatment, however, induced novel P2X(3) expression, with intense immunoreactivity in axons projecting to lamina I and outer lamina II and to the ventro-medial afferent bundle beneath the central canal. In the normal DRG, we found a greater proportion of P2X(3)-positive neurons at cervical levels, many of which were large-diameter and calcitonin gene-related peptide-positive. In both cervical and lumbar DRG, the number of P2X(3)-positive cells increased following GDNF or NGF treatment. De novo expression of P2X(3) in NGF-sensitive nociceptors may contribute to chronic inflammatory pain.  相似文献   
948.
MK—801降低炎性痛在鼠脊髓NOS表达和NO含量   总被引:15,自引:2,他引:13  
Zeng JB  Li WB  Li QJ  Chen XL  Zhou AM  Ling YL 《生理学报》2001,53(1):55-60
用NADPH-d组织化学法,观察鞘内注射NMDA受体拮抗剂MK-801对大鼠右后掌皮下注射甲醛诱发的炎症性痛及痛过敏过程中脊髓后角一氧化氮合酶(NOS)表达的影响,同时测定一氧化氮(NO)代谢终产物  相似文献   
949.
神经病理性痛的交感—感觉耦联作用   总被引:4,自引:0,他引:4  
Xu H  Hu SJ 《生理科学进展》2001,32(2):111-115
周围组织和神经受到损伤引起自发性疼痛、触刺激诱发痛和痛觉过敏等慢性痛症状。交感神经系统通过发展异常交感功能,或者通过影响传入神经异常活动参与上述的病理性变化,进而造成神经病理性痛。本文对目前关于交感-感觉耦联作用及其受体、细胞内和神经机制进行综述。  相似文献   
950.
Eleven clones of a single strain of Leishmania infantum (MCAN/ES/88/ISS441, Doba) were analyzed for biological behavior in vivo and in vitro. Different clones showed differences in growth dependent upon the two culture media employed. All clones displayed only slight differences in H2O2 and NaNO2 sensitivity compared to the original strain, whereas in vitro infectivity for mouse peritoneal macrophages differed significantly among the clones. In vivo infections in hamsters correlated strongly with in vitro infectivity. The phenotypic differences found suggest a polyclonal structure for the Leishmania infantum strain studied.  相似文献   
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