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51.
健脾益气对神经内分泌免疫网络影响的实验研究   总被引:11,自引:1,他引:11  
为了观察健脾益气对神经内分泌免疫网络的调节作用,本实验用皮质酮(10mg/kg)造成大鼠下丘脑—垂体—肾上腺—胸腺(HPAT)轴抑制模型,观察健脾益气代表名方四君子汤(SJ)对HPAT轴的影响。结果表明皮质酮大鼠下丘脑单胺类递质的含量明显增高,血浆ACTH、CORT含量明显降低,体内与体外淋巴细胞增殖反应明显受抑,自然杀伤细胞活性下降,淋巴细胞诱生的IL—2和γ—IFN水平明显降低。200%四君子汤灌胃(10g/kg)能有效改善神经和免疫功能,而对内分泌系统作用不明显。桃红四物汤(TH)对皮质酮大鼠HPAT轴无影响  相似文献   
52.
53.
Oleamide (cis-9,10-octadecenoamide) is an endogenous sleep-inducing lipid and prototypic member of a new class of biological signaling molecules identified in recent years. In the present study, the anxiolytic-like effect of oleamide was studied in several experimental models of anxiety in group-housed and socially isolated mice. As the results show, socially isolated mice exhibited an anxiogenic-like profile in the elevated plus-maze test, the light/dark test, and the hole-board test, which could be significantly reversed by oleamide (10 or 20 mg/kg, i.p.). Moreover, oleamide significantly reduced the anxiety levels in grouped-housed mice. In the isolation-induced aggressive test, oleamide markedly reduced the attacking duration and increased the attacking latency. It is concluded that oleamide has an anxiolytic-like effect in socially isolated or group-housed mice, which suggests that fatty acid amides might be involved in the regulation of anxiety-related behavior in mice.  相似文献   
54.
The 21st century ushered in the century of human beings. The previous era characterized by the chase after super technology has been replaced by a new era which focuses on the meaning of human existence and quality of life. Clinical practice has accordingly also undergone rapid change. Amongst the many competing technologies, clearly magnetic resonance technology, especially ultra high-field magnetic resonance imaging, plays a major role in defining current clinical practice. Elimination of all invasive aspects from diagnostic imaging, including intravenous infusion or use of ionizing radiation, is one of the final goals of the new generation of clinical imaging. This goal is especially worthwhile when one consider the welfare of children. Technological MRI advancements are steadily bridging the gap towards this goal. With T2 reversed and three-dimensional anisotropy (3DAC) contrast imaging on a 3.0T system, the anatomical resolution of routine clinical images has reached a level of resolution equivalent to general pathology. Realistic imaging microscopy application is also on the horizon with the establishment of clinical 7.0T systems. Individual brain activation maps can now be readily obtained under clinical settings thanks to high-field functional MRI (fMRI). Nevertheless, because active self-organizing processes of cortical functionalities are under active development in the pediatric population, fMRI has only limited, if any, clinical usage in children. Similarly, whereas connectivity analysis in the individual patient using diffusion tensor imaging (DTI) has little clinical usage in the pediatric population, DTI can be successfully applied to multiple subject analysis for exploring unknown connectivity abnormalities in this age group. Magnetic resonance spectroscopy (MRS) and its pictorial display (spectroscopic imaging) is now finding more and more clinical applications across the age spectrum of patients.  相似文献   
55.

Ethnopharmacological relevance

Traditional Chinese medicine (TCM), which is fundamentally different from Western medicine, has been widely investigated using various approaches. Cellular- or molecular-based imaging has been used to investigate and illuminate the various challenges identified and progress made using therapeutic methods in TCM. Insight into the processes of TCM at the cellular and molecular changes and the ability to image these processes will enhance our understanding of various diseases of TCM and will provide new tools to diagnose and treat patients.

Materials and methods

Various TCM therapies including herbs and formulations, acupuncture and moxibustion, massage, Gua Sha, and diet therapy have been analyzed using positron emission tomography, single photon emission computed tomography, functional magnetic resonance imaging and ultrasound and optical imaging. These imaging tools have kept pace with developments in molecular biology, nuclear medicine, and computer technology.

Results

We provide an overview of recent developments in demystifying ancient knowledge - like the power of energy flow and blood flow meridians, and serial naturopathies - which are essential to visually and vividly recognize the body using modern technology.

Conclusions

In TCM, treatment can be individualized in a holistic or systematic view that is consistent with molecular imaging technologies. Future studies might include using molecular imaging in conjunction with TCM to easily diagnose or monitor patients naturally and noninvasively.  相似文献   
56.
The termination of an unpleasant or painful somatic condition can produce a rewarding sense of relief, even if the stimulus that causes the termination is itself unpleasant or painful under normal circumstances. We aimed to identify central neural mechanisms of pain relief from capsaicin-elicited heat-hyperalgesia by administering cold stimuli. We hypothesized that cooling might facilitate endogenous descending inhibitory mechanisms. We compared intraindividual neural responses of 15 healthy male volunteers to cold (20, 0 degrees C), intermediate (30 degrees C) and heat stimuli (43 degrees C) on untreated vs. capsaicin-treated skin using event-related fMRI in a 2 x 4 factorial design. Thermal stimuli were applied at the right hand in two separate imaging sessions using a Peltier-element. Psychophysical ratings of the perceived valence and intensity (VAS: 1-100) were obtained after each stimulus. The 43 degrees C-stimulus was perceived as excessively painful on capsaicin-treated skin as opposed to an unpleasant sensation on normal skin. In contrast, the 0 degrees C-stimulus was perceived unpleasant when applied on untreated skin while subjects rated the same stimulus pleasant in the capsaicin-treated condition. When neural responses to the 0 degrees C-stimulus were compared between the untreated and capsaicin-treated skin condition there were stronger BOLD-responses in prefrontal cortex (PFC) and periaqueductal grey (PAG) which correlated with increasing perceived pleasantness (VAS). Based on a connectivity analysis which identified cold-dependent contributions of PFC activity with PAG in heat-hyperalgesia we propose that cold-induced pain relief partly results from activation of endogenous descending inhibition of nociception. The data illustrate that perception of nociceptive input may largely be determined by competing aversive-appetitive motivational states.  相似文献   
57.

Introduction

Ozone has been proposed as an antioxidant enzyme activator, immunomodulator and cellular metabolic activator. This study was designed to investigate the efficacy of ozone therapy in the prevention of esophageal damage and stricture formation developed after esophageal caustic injuries in the rat.

Materials and Methods

Forty-five rats were allocated into three groups; sham-operated, un-treatment and treatment groups. Caustic esophageal burn was created by instilling 15% NaOH in the distal esophagus. The rats were left untreated or treated with 1 mg/kg/day ozone intraperitoneally. All rats were sacrificed at 28 days. Efficacy of the treatment was assessed by measuring the stenosis index (SI) and histopathologic damage score, and biochemically by determining tissue hydroxyproline content (HP), superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA) and protein carbonyl content (PCC) in esophageal homogenates.

Results

Whereas seven (47%) rats died in the un-treatment group, all rats in the sham-operated and the treatment group survived during the study. SI, the histopathologic damage score, was significantly lower in the ozone-therapy group than the un-treatment group. HP levels were significantly higher in the un-treatment group than the group treated with ozone. Caustic esophageal burn increased MDA and PCC levels and also decreased SOD and GPx enzyme activities. In contrast, ozone therapy decreased the elevated MDA and PCC levels and also increased the reduced SOD and GPx enzyme activities.

Conclusion

Ozone has a preventive effect in the development of fibrosis by decreasing tissue damage and increasing the antioxidant enzyme activity in an experimental model of corrosive esophageal injury.  相似文献   
58.
Antimalarial activity of alkaloids isolated from Stephania rotunda   总被引:2,自引:0,他引:2  
Stephania rotunda (Menispermaceae) is used in traditional medicine for the treatment of fever. Four major alkaloids: dehydroroemerine, tetrahydropalmatine, xylopinine, cepharanthine as well as aqueous extract (SA), dichloromethane extracts (SD1 and SD2) from this plant were tested against Plasmodium falciparum W2 in vitro. Dehydroroemerine, cepharanthine and SD1 were the most active against W2 with IC(50) of 0.36, 0.61microM and 0.7microg/mL, respectively. Their IC(50) on human monocytic THP1 cells were 10.8, 10.3microM and >250microg/mL, respectively. Cepharanthine, SD1 and SA were selected for in vivo antimalarial test against Plasmodium berghei in mice. The results of SD1 and SA at dose of 150mg/kg showed a decrease of 89 and 74% of parasitaemia by intra-peritoneal injection and 62.5 and 46.5% of parasitaemia by oral administration, respectively. The result of cepharanthine at dose of 10mg/kg showed a decrease of 47% of parasitaemia by intra-peritoneal injection and 50% of parasitaemia by oral administration. Drug interaction of chloroquine and major alkaloids indicates that cepharanthine-chloroquine and tetrahydropalmatine-xylopinine associations are synergistic. These results are in agreement with the use of this plant in the treatment of malaria. This is the first report on in vivo antimalarial investigation for Stephania rotunda.  相似文献   
59.
BackgroundTo evaluate the safety and efficacy of single incision plus one (SI+1) port three-dimensional (3D) laparoscopic minimally invasive esophagectomy (MIE).MethodsClinical data of patients who underwent 3D thoracic laparoscopic MIE in our department from September 2020 to March 2021 were analyzed retrospectively. According to the different methods of laparoscopic surgery, the patients were divided into 2 groups: SI+1 port 3D laparoscopy group and multiportal 3D laparoscopy group. The operation time of the 3D laparoscopy component, amount of intraoperative blood loss, number of celiac lymph node dissections, postoperative abdominal drainage days, postoperative total abdominal drainage, postoperative complications, and length of hospital stay were analyzed.ResultsThere was no significant difference between the 2 methods in laparoscopic operation time (30.11±5.86 vs. 28.45±4.72 min, P=0.49), intraoperative blood loss (34.44±9.82 vs. 35.91±6.25 mL, P=0.69), number of celiac lymph node dissections (8.44±3.13 vs. 7.09±2.12, P=0.27), postoperative abdominal drainage days (3.11±0.33 vs. 3.00±0.00 days, P=0.28), postoperative total abdominal drainage (95.00±23.33 vs. 92.27±11.26 mL, P=0.74), postoperative complications (22.2% vs. 27.3%, P=0.33), and hospital stay (9.67±0.71 vs. 10.18±0.87 days, P=0.17). None of the patients enrolled in the study had recurrence or death to date.ConclusionsThe application of SI+1 port 3D laparoscopy in minimally invasive resection of esophageal carcinoma is safe and feasible.  相似文献   
60.
SI units     
Measurements are performed every day by anaesthetists. An understanding of measurement is required for examinations in anaesthesia and daily practice. This article describes the history behind the International System of Units (SI), current definitions and the most recent changes. Non-SI units are also described. A summary of SI unit naming conventions is given.  相似文献   
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