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1.

Objective

Humans can acquire a wide variety of motor skills using sensory feedback pertaining to discrepancies between intended and actual movements. Acupuncture needle manipulation involves sophisticated hand movements and represents a fundamental skill for acupuncturists. We investigated whether untrained students could improve their motor performance during acupuncture needle manipulation using visual feedback (VF).

Methods

Twenty-one untrained medical students were included, randomly divided into concurrent (n = 10) and post-trial (n = 11) VF groups. Both groups were trained in simple lift/thrusting techniques during session 1, and in complicated lift/thrusting techniques in session 2 (eight training trials per session). We compared the motion patterns and error magnitudes of pre- and post-training tests.

Results

During motion pattern analysis, both the concurrent and post-trial VF groups exhibited greater improvements in motion patterns during the complicated lifting/thrusting session. In the magnitude error analysis, both groups also exhibited reduced error magnitudes during the simple lifting/thrusting session. For the training period, the concurrent VF group exhibited reduced error magnitudes across all training trials, whereas the post-trial VF group was characterized by greater error magnitudes during initial trials, which gradually reduced during later trials.

Conclusions

Our findings suggest that novices can improve the sophisticated hand movements required for acupuncture needle manipulation using sensorimotor learning with VF. Use of two types of VF can be beneficial for untrained students in terms of learning how to manipulate acupuncture needles, using either automatic or cognitive processes.  相似文献   

2.
Pullout of implants at the proximal and distal ends of multilevel constructs represents a common spinal surgery problem. One goal concerning the development of new spinal implants is to achieve stable fixation together with the least invasive approach to the spinal column. This biomechanical study measures the influence of different modes of implantation and different screw designs, including a new monocortical system, on the maximum pullout strength of screws inserted ventrolaterally into calf vertebrae. The force pullout of eight different groups were tested and compared. Included were three bicortical used single screws (USS, Zielke-VDS, single KASS). To further increase pullout strength either a second screw (KASS) or a pullout-resistant nut can be added (USS with pullout nut). A completely new concept of anchorage represents the Hollow Modular Anchorage System (MACS-HMA). This hollow titanium implant has an increased outside diameter and is designed for monocortical use. Additionally two screw systems suitable for bicortical use were tested in monocortical mode of anchorage (USS, single KASS). We selected seven vertebrae equal in mean size and bone mineral density for each of the eight groups. The vertebral body and implant were connected to both ends of a servohydraulic testing machine. Displacement controlled distraction was applied until failure at the metal-bone-interface occurred. The maximum axial pullout force was recorded. Mean BMD was 312 +/- 55 mg CaHA/ml in cancellous bone and 498 +/- 98 mg CaHA/ml in cortical bone. The highest resistance to pullout found, measured 4.2 kN (KASS) and 4.0 kN (USS with pullout nut). The mean pullout strength of Zielke-VDS was 2.1 kN, of single KASS 2.5 kN, of MACS-HMA 2.6 kN and of USS 3.2 kN. There was no statistically significant difference (t-test, p > 0.05) between bicortical screws and the new monocortical implant. For the strongest fixation at the proximal or distal end of long spinal constructs the addition of a second screw or a pullout-resistant nut behind the opposite cortex offers even stronger fixation.  相似文献   

3.
Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge. Recently, needles with the potential for double-blinding were developed, so we tested if acupuncture can be double-blinded in a randomized study of sixty-seven patients with acute pain ≥ 3 (0-10 scale following third molar removal) who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle. To test if acupuncture was administered double-blind, patients and acupuncturists were asked about perceived treatment allocation at the end of the study. To test if there were clues which led to identification of the treatment, deep dull pain associated with needle application and rotation (termed “de qi” in East Asian medicine), and patients’ pain levels were assessed. Perceived treatment allocation depended on actual group allocation (p < 0.015) for both patients and acupuncturists, indicating that the needles were not successful in double-blinding. Up to 68% of patients and 83% of acupuncturists correctly identified the treatment, but for patients the distribution was not far from 50/50. Also, there was a significant interaction between actual or perceived treatment and the experience of de qi (p = 0.027), suggesting that the experience of de qi and possible non-verbal clues contributed to correct identification of the treatment. Yet, of the patients who perceived the treatment as active or placebo, 50% and 23%, respectively, reported de qi. Patients’ acute pain levels did not influence the perceived treatment. In conclusion, acupuncture treatment was not fully double-blinded which is similar to observations in pharmacological studies. Still, the non-penetrating needle is the only needle that allows some degree of practitioner blinding. The study raises questions about alternatives to double-blind randomized clinical trials in the assessment of acupuncture treatment.  相似文献   

4.
A study was designed to establish whether acupuncture has any analgesic properties beyond those of suggestion. In three one-hour experimental sessions the increases in detection thresholds and tolerances for thermal pain at six body locations on 12 subjects were compared. A control session (without needles) was followed by one session in which electrically stimulated needles were inserted in accord with Chinese practice, and another in which the needles were inserted to avoid all recognised acupuncture "points." Acupuncture was significantly more effective than suggestion in raising overall body pain thresholds but just below significance for tolerances. A significant disproportionate effect on the epigastrium, predicted by the choice of acupuncture points, was found for tolerances but not thresholds.  相似文献   

5.
摘要 目的:探讨"调神畅志"针刺法对帕金森伴便秘(Parkinson''s disease with constipation)模型大鼠结肠组织中5-羟色胺4受体(5-HT4R)及钙调蛋白(CaM)-肌球蛋白轻链激酶(MLCK)信号通路影响的研究,并探讨其可能作用机制。方法:采用随机数字表将60只大鼠分为空白组、假手术组、模型组、西药组、常规针刺组、调神畅志针刺组,每组10只。模型组、常规针刺组、调神畅志针刺组颈背部皮下注射鱼藤酮的方法制造PDD大鼠模型,并用阿扑吗啡(APO)诱导检测。常规针刺组选取天枢、足三里、上巨虚及舞蹈震颤控制区,接电针,连续波频率15Hz,刺激强度2 mA,留针30分钟,1日1次,连续4周;调神畅志针刺组:选取王顺教授 " 调神畅志 " 三六九针法,百会透太阳、中脘、气海、足三里、太冲,采用连续波,头针频率45Hz,腹针频率30Hz,肢体针频率15Hz(体现调神畅志三六九针法的头针重、腹针中、四肢针轻的量化刺激),刺激强度约2 mA,留针30 min,1日1次,连续4周;西药组采用美多芭、莫沙必利每日灌胃,连续治疗4周;模型组、假手术组:每日2 mL生理盐水灌胃,连续4周;空白组不予处理。采用Western blot法检测各组近端结肠组织中5-HT4R、CaM及MLCK蛋白表达以及含量水平。结果:与空白组相比,模型组大鼠近端结肠组织中5-HT4R、CaM及MLCK蛋白表达水平显著降低(P<0.01),与模型组比较,三个治疗组(西药组、常规针刺组、调神畅志针刺组)近端结肠组织5-HT4R、CaM及MLCK蛋白表达水平显著升高(P<0.01)。与常规针刺组相比,调神畅志组5-HT4R、CaM及MLCK蛋白表达水平明显升高(P<0.05)。结论:针刺可改善PD伴便秘大鼠模型便秘症状,且调神畅志针刺组优于常规针刺组,其作用机理可能通过调节大鼠结肠组织中5-HT4R蛋白表达以及激活CaM-MLCK信号通路来实现的。  相似文献   

6.
7.
Acupuncture needle rotation has been previously shown to cause specific mechanical stimulation of subcutaneous connective tissue. This study uses acupuncture to investigate the role of mechanotransduction-based mechanisms in mechanically-induced cytoskeletal remodeling. The effect of acupuncture needle rotation was quantified by morphometric analysis of mouse tissue explants imaged with confocal microscopy. Needle rotation induced extensive fibroblast spreading and lamellipodia formation within 30 min, measurable as an increased in cell body cross sectional area. The effect of rotation peaked with two needle revolutions and decreased with further increases in rotation. Significant effects of rotation were present throughout the tissue, indicating the presence of a response extending laterally over several centimeters. The effect of rotation with two needle revolutions was prevented by pharmacological inhibitors of actomyosin contractility (blebbistatin), Rho kinase (Y-27632 and H-1152), and Rac signaling. The active cytoskeletal response of fibroblasts demonstrated in this study constitutes an important step in understanding cellular mechanotransduction responses to externally applied mechanical stimuli in whole tissue, and supports a previously proposed model for the mechanism of acupuncture involving connective tissue mechanotransduction.  相似文献   

8.
Needle traces have been used for revealing historical changes in needle longevity of Pinus sylvestris L. and Picea abies (L.) H. Karst. In this paper we compared the needle-trace diameter of five conifer species [Abies sibirica Ledeb., Picea abies, Pinus sylvestris, Pseudotsuga menziesii (Mirb.) Franco and Taxus baccata L.] in respect of needle size. In case of P. sylvestris, we studied how needle-trace diameter varied among different growing sites and among different shoots within a site, and related that variation to needle morphology and structure. Pinus sylvestris had the greatest diameter of needle traces (mean±SD =233±30 m) followed by T. baccata (141±19 m) and P. menziesii (121±30 m). The smallest needle-trace diameter was in A. sibirica (85±21 m) and P. abies (80±18 m). Among species, the needle-trace diameter was strongly correlated with needle length (r =0.93, P <0.05). Within P. sylvestris, the needle-trace diameter was significantly affected by location (P <0.001) and varied significantly among shoots within a location (P <0.001). The shoots of P. sylvestris which had greater average diameter of needle traces, tended to have longer (r =0.36, P <0.05), wider (r =0.55, P <0.05) and heavier (r =0.64, P <0.05) needles with greater stomatal density (r =0.55, P <0.05). Although our results do not allow the use of needle-trace diameter to predict properties of needle structure at the present stage, they nevertheless indicate general trends and point to a need for further studies.  相似文献   

9.
10.
The effects of partial debudding on photosynthesis, stomatal conductance and nitrogen contents of 1-year-old needles and newly grown needles were studied in Picea jezoensis (Sieb. et Zucc.). Seventy-five percent of the buds of P.jezoensis seedlings were removed soon after bud break. Gas exchange was measured three times for 1-year-old needles and twice for current-year needles. The photosynthetic rates of 1-year-old needles were greater in debudded seedlings than in control seedlings, and the difference increased as the growing season progressed. This greater photosynthetic rate in debudded seedlings was accompanied by greater stomatal conductance. However, neither the photosynthetic rates nor the stomatal conductance of current-year needles differed between debudded and control seedlings after the needles had fully expanded. Debudding also had no effect on mass-based nitrogen contents in either the 1-year-old or the current-year needles. Area-based nitrogen in the 1-year-old needles did not differ between debudded and control seedlings, but was greater in debudded seedlings than in control seedlings in current-year needles. These results suggest that the enhanced photosynthetic rate is more likely a result of an increased root/leaf ratio that reduces the stomatal limitation of photosynthetic rate than a result of altered sink-source relationships or increased leaf nitrogen content.  相似文献   

11.
Age and shade effects on needle structure and photosynthesis were determined within a lower part of Abies alba crown along a horizontal increasing gradient of branches self-shading. It was hypothesized that a decrease in net CO2 assimilation rate with increasing needles’ age would be related to: (1) structural age-related changes in needles, (2) reduction of stomatal conductance, (3) nitrogen translocation from old to young needles, and (4) decrease in efficiency of photochemical processes. Leaf mass-to-area ratio increased non-linearly with needle age. In a needle cross section, distance between the vascular bundles decreased, and height of palisade parenchyma cells increased with age. The structural changes observed in our study might lead to an increase in internal resistance to CO2 with greater needle age. Total needle nitrogen concentration linearly decreased with age due to dilution and/or translocation to younger needles. When expressed per needle area, nitrogen content was reduced in 6-year-old needles compared with younger ones. Net CO2 assimilation rate per needle area decayed and was accompanied by a decrease in transpiration and water and photosynthetic nitrogen use efficiency. Old needles maintained high photochemical efficiency which compensated to some extent for light deficit in their micro-light environments. Our results have suggested that there is a mechanism controlling the relation between efficiency of light and dark photosynthetic processes along the needle age and shade gradient in A. alba crown.  相似文献   

12.
Light-saturated net photosynthesis (Asat), dark respiration (RD), and foliar nutrient content of eight European Scots pine (Pinus sylvestris L.) provenances were measured at experimental sites in western Poland. Two-year-old seedlings were planted in 1984 at two sites with similar soils in areas of contrasting air pollution. One site was near a point source of SO2 and other pollutants, and another 12 km to the southeast in an area free of acute air pollution was treated as a control. The eight provenances were from a large north-tosouth latitudinal range (60 to 43° N). At the heavily polluted site Scots pine trees exhibited lower growth rates and crown dieback and deformation. Soil pH, Ca and Mg were at least 10 times lower, and Al 10 times higher at the polluted than the control site. In 1991, concentrations of Al, P, Ca, S, Mn, Fe, and Zn in oneyear old Scots pine foliage were higher and Mg lower at the polluted than control site. At both sites foliar Mg levels were within the range considered deficient (0.6 mg g-1), and at the polluted site, Al concentrations were very high (670 to 880 g g-1). In all provenances, RD of one-year-old needles was higher (by 22% on average) and Asat was lower (by 37% on average) at the polluted than the control site. The ratio of Asat: RD was half as great in all provenances at the polluted (4 to 6) than control site (8 to 11). Provenances of southern origin had greater increases in RD and water-use efficiency at the polluted site than other provenances. Within the polluted site alone, or across both sites, Asat in Scots pine was negatively correlated to the Al: Ca ratio (p<0.001, r=–0.93). Across sites RD increased with needle N and Al (multiple regression, p<0.001). The data suggest that at the polluted site there is excessive soil Al and deficient Mg availability, low needle Mg and high Al concentrations and high Al: Ca ratios, and that these have resulted in reduced photosynthetic capacity and increased respiration.  相似文献   

13.
Summary This study evaluated the contribution of different ages of foliage to the nutrient and carbon balance of black spruce (Picea mariana (Mill.) B.S.P.) from a nutrient-poor peatland in Alberta. Seasonal patterns of foliar nitrogen and phosphorus concentration and content were examined in six needle cohorts up to 10 years old. Trees were treated to simulate excess nutrient deficiency (removal of all one-year-old foliage), nutrient excess (fertilized with 250, 50, 100 kg ha–1 NPK split application in June and July), or left as controls. Gas exchange (net assimilation-Na, stomatal conductance-gs, mesophyll conductance-gm, water-use efficiency-WUE, dark respiration-RS) was measured on six different needle cohorts in several control trees in 1989 and 1990. Nitrogen and phosphorus concentration decreased with needle age. Foliar nutrient concentration fell from April to June and then was stable until September except for the fertilized trees where it increased. There was no evidence of greater than normal retranslocation of nutrients from older needles for defoliated trees or greater than normal nutrient loading in older needles of fertilized trees. NA, gs, gm, WUE, and RS were similar for all needles up to six or eight years old, these older needles having NA of 65% of current needles and similar RS. The results do not support to conclusion that older needles of black spruce are retained as an adaptation to nutrient stress. It does not appear that older needles serve as a nutrient storage site in conditions of excess nutrient availability or a greater than normal nutrient source during times of excess nutrient deficiency. It appears that the maintenance of long-livedfoliage in black spruce does not provide for greater flexibility in tree nutrient allocation. Their contribution to the carbon balance of the tree seems to be sufficient to explain their retention.  相似文献   

14.
Summary The effect of ozone, needle age, and season on the pH of homogenate and acid contents of Scots pine and Norway spruce needles is presented. In addition enzyme activities of cytochrome C-oxidase (cyt. C-ox), phosphoenolpyruvate-carboxylase (PEPC), shikimic acid-dehydrogenase (SHDH) and malate-dehydrogenase (MDH) were measured in Scots pine needles. In freshly sprouted spruce needles the level of quinic acid is high and the pH of the needle homogenate is low. Shikimic acid starts at low levels, increases with increasing needle age and becomes dominant, whereas the quinic acid content decreases. Malic acid has a marked seasonal trend; no trend was found in citric acid. Ozone (200 g/m3) decreased shikimic acid and quinic acid, whereas pH, malic acid and citric acid increased. Ozone (100 g/m3) had a similar effect, except in the current-year spruce needles. In Scots pine needles ozone led to increased enzymatic activities of cyt. C-ox, PEPC and SHDH, and a decrease in the activity of MDH. This effect was more pronounced in summer than in autumn, but the visible damage was greater in autumn. These effects can be found with other stresses and are not specific for ozone.  相似文献   

15.
在婴幼儿HBV高感染村,实施一人一针一管一用一消毒的严格措施后,使一岁儿童HBV感染率下降53.0%,HBsAg阳性率下降55.5%,使HBsAg阴性母亲的1~2岁儿童HBV感染率下降64.6%~76.4%,HBsAg阳性率降低78.6%~81.9%。  相似文献   

16.
Monoterpene levels in current year needles of Douglas fir ( Pseudotsuga menziesii (Mirb.) Franco) seedlings were measured at the end of 4 years of exposure to ambient or elevated CO2 (+179 µmol mol−1), and ambient or elevated temperature (+0.3.5^C). Eleven monoterpenes were identified and quantified using gas chromatography/flame ionization detector/mass spectroscopy, with eight of these compounds regularly occurring in all trees examined. Elevated CO2 exposure significantly reduced the levels for four of the eight main compounds in needles. Total monoterpene production was reduced by 52% ( P  < 0.05). Elevated temperature also reduced monoterpene levels ( P  < 0.07). The combination of elevated temperature and elevated CO2 resulted in a 64% reduction in total monoterpenes compared with needles on ambient temperature trees. Two-way anova showed no significant temperature-CO2 interaction. It is hypothesized that seasonal reductions in needle monoterpene pools under elevated CO2 and temperature conditions may be due to a combination of competing carbon sinks, including increased carbon flux through the roots.  相似文献   

17.
W. H. Parry  W. Powell 《Oecologia》1977,27(3):239-252
Summary No difference in the rate of symptom development and needle loss was evident between resistant and susceptible trees. Population growth rates, which were higher on current year needles in the upper crown, adult weights, reproductive state and instar ratios were similar for aphids from both resistant and susceptible trees. Overwintering survival rates were higher on susceptible trees and were the main cause of the higher number of aphids found on susceptible trees and on the lower crown in comparison with the resistant trees and the upper crown. The supercooling points of needles from resistant trees were higher than those from susceptible trees during the three coldest months of the year-December, January and February. As the aphid freezes at the same temperature as the needle on which it feeds differences in needle freezing temperatures can result in greater aphid mortality on the resistant trees at the temperatures prevailing in NE Scotland during the period of the study. No correlation was found between provenance latitude and supercooling ability of the needles although a very great variability was evident between individual trees. Changes in the form of the super-cooling temperature frequency curves indicated a gradual increase in the quantity of nucleators present in the spruce needles during the winter, the change being more pronounced in the resistant needles.  相似文献   

18.
Summary Monoterpenes in needles of Picea abies (L.) Karst. were studied to reveal whether or not the symptoms of forest decline observed in three mountain regions of South Germany (Bavaria) — needle loss and needle yellowing — are related to changes in the amounts of all or individual terpenes. The nutrient supply of the needles was examined in addition to the terpene concentrations, since the disease symptom montane yellowing is often associated with mineral deficiency. At two of the eight locations, trees exhibited Mg-deficiency, at one location K-deficiency was observed, and at another location the S-content of the needles indicated SO2-pollution. Using various statistical methods of analysis, no correlation was observed between the mineral element content of the needles, the percentage of needle loss and either the absolute or percentile terpene amounts stored within the needles. This finding is independent of needle age, date of sampling and terpene pattern. Concerning needle yellowing, the data show a tendency towards a reduction of the terpene concentrations in needles originating from branches with partly yellow needles compared to needles from exclusively green-needled branches. In spite of the fact that only 2-year-old and older needles show the disease symptom of yellowing, the terpene level is reduced even in still green, juvenile and 1-year-old needles. No terpene was found to be an indicator for early recognition of injury.  相似文献   

19.
Radio frequency energy (RFE) thermal chondroplasty has been a widely-utilized method of cartilage debridement in the past. Little is known regarding its effect on tissue mechanics. This study investigated the acute biomechanical effects of bipolar RFE treatment on human chondromalacic cartilage. Articular cartilage specimens were extracted (n?=?50) from femoral condyle samples of patients undergoing total knee arthroplasty. Chondromalacia was graded with the Outerbridge classification system. Tissue thicknesses were measured using a needle punch test. Specimens underwent pretreatment load-relaxation testing using a spherical indenter. Bipolar RFE treatment was applied for 45?s and the indentation protocol was repeated. Structural properties were derived from the force-time data. Mechanical properties were derived using a fibril-reinforced biphasic cartilage model. Statistics were performed using repeated measures ANOVA. Cartilage thickness decreased after RFE treatment from a mean of 2.61?mm to 2.20?mm in Grade II, II-III, and III specimens (P?相似文献   

20.
马尾松毛虫对马尾松和湿地松的选择与适应研究   总被引:2,自引:2,他引:0  
用马尾松老叶、新叶,湿地松老叶、新叶,当年生马尾松新叶、湿地松新叶和当年生以20%和40%β-蒎烯处理过的马尾松新叶作食料饲养马尾松毛虫。结果表明:马尾松毛虫幼虫在第1代发生期取食马尾松老叶、马尾松新叶、湿地松老叶和湿地松新叶等4种不同质量的食料后,因其食料中10种必需氨基酸含量和挥发性物质β-蒎烯含量的不同,导致幼虫的存活率差异显著。其中,取食马尾松老叶的幼虫成活率最高(44%),依次为马尾松新叶(32.7%)、湿地松老叶(4%),而取食湿地松新叶的幼虫全部死亡。通过马尾松针叶增加外援β-蒎烯喂养马尾松毛虫实验,表明增加了外源β-蒎烯的松针饲养的马尾松毛虫幼虫与用同样松针未增加外源β-蒎烯饲养的幼虫相比,死亡率明显提高;松树中β-蒎烯含量的增加与幼虫成活率呈显著负相关。由此,我们阐明了马尾松与湿地松对马尾松毛虫的抗虫机制。  相似文献   

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