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51.
The authors report the case of a 33-year-old woman who exhibited, at the age of 17, a left-sided hemiplegia, which was followed by good motor recovery, though with a permanent deficit in fine finger movements. She had a widespread loss of neural tissue in the right hemisphere (crossed cerebrocerebellar atrophy), including (1) marked atrophy and thinning of the precentral and postcentral gyri; (2) widespread deep white matter destruction, including the corticospinal tract; and (3) crossed cerebellar atrophy. Except over the supplementary motor area (SMA), transcranial magnetic stimulation did not elicit motor evoked potentials in the affected hand. Nevertheless, during opening and closing of the affected hand, functional magnetic resonance imaging showed an activation of the lesioned primary sensorimotor cortex (SMC), as well as of the intact SMA and the parietal areas, but not of the ipsilateral motor areas. The authors speculate that recovery was achieved by a motor command generated in the SMC and the parietal cortex, passing through corticospinal axons originating in the SMA.  相似文献   
52.
目的研究不同月龄的雄性大鼠成骨细胞内钙浓度及钙通道电流是否存在差异.方法采用二次酶消化法分离不同月龄(分别为1、2、3、5、7、9、11、13、15)雄性大鼠的原代成骨细胞,通过激光扫描共聚焦技术测定细胞内游离钙浓度([Ca2+]i)(以平均荧光强度表示),同时应用全细胞膜片钳技术记录成骨细胞膜钙电流(ICa)的变化.结果共聚焦结果显示随月龄增加,成骨细胞内[Ca2+]i逐渐降低,但相邻2月龄组之间细胞内[Ca2+]i无显著性差异(P>0.05);1、2、3月龄组与11、13、15月龄组成骨细胞内[Ca2+]i有显著性差异(P<0.05),5、7、9月龄组与各组相比均无差异(P>0.05).应用全细胞膜片钳技术发现刺激电压为+10 mV时,2、7、13月龄组鼠ICa分别为(-392.77±97.07)pA、(-330.33±33.86)pA和(-287.68±71.01)pA,13月龄组鼠与2月龄组鼠相比,ICa明显降低(P<0.05),而7月龄组鼠与2月龄组鼠和13月龄组鼠相比,ICa均没有明显差异(P>0.05).结论不同月龄大鼠成骨细胞内[Ca2+]i存在差异,其机制可能与细胞膜上钙通道活性改变相关.  相似文献   
53.
The acromioclavicular joint is a potential source of pain in the shoulder. There are a variety of disorders that can affect this joint, including distal clavicle osteolysis, posttraumatic arthritis, osteoarthritis, and rheumatoid arthritis. Nonoperative treatment for this condition with nonsteroidal medication and activity modification can alleviate the pain. When conservative treatment is exhausted, surgical resection of the distal clavicle is often necessary. Arthroscopic resection of the distal clavicle preserves the acromioclavicular ligaments to prevent postoperative distal clavicle instability. The procedure is performed in either the beach chair or lateral position and requires the use of a shaver, electrocautery, and a burr for soft tissue and debridement and bone resection.  相似文献   
54.
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1.  相似文献   
55.
To assess the curative effects of different reduction techniques on the dislocation of cricoarytenoid joint caused by intubation,indirect laryngoscope (IL) and direct laryngoscope (DL) were utilized for the closed reduction of the displaced arytenoid under local anesthesia.23 patients who underwent the reduction for dislocated arytenoid under IL or DL from January 1991 to June 2001 were reviewed.The data were collected on the duration of the laryngeal injury,times of receiving reduction,side-effects after the treatment and the period for voice to returen to normal.The relationship between the duration of the laryngeal lesion and the period of the voice rehabilitation was examined.13 patients received the reduction under IL and 10 patients under DL,Except the times of the reduction,which showed significant difference,no differences were found between IL group and DL group in the course and the period of voice rehabilitation,as well as sore throat after the manipulation.The patients‘ voice recovery was positively related to their course of disease in both IL and DL group.It is coucluded that the recovery of normal voice is obviously affected by the duration of arytenoid dislocation.The reduction under Il is as effective as under DL in the treatment of arytenoid dislocation.Reduction by DL is better suit the patients with long time course of disease.  相似文献   
56.
右美沙芬对兔急性脑外伤后脑血流速度的影响   总被引:1,自引:0,他引:1  
目的 :应用经颅多普勒超声 (TCD)技术研究右美沙芬治疗兔颅脑急性损伤后脑血流速度的变化及其意义。方法 :健康雄性白家兔 2 0只 ,随机分为 2组。A组 (n =1 0 )为脑外伤组 ,B组 (n =1 0 )为脑外伤后右美沙芬治疗组。应用TCD分别测定外伤前、伤后 5min、6h、72h、1 6 8h兔大脑中动脉 (MCA)脑血流速度。观察指标为收缩期血流速度 (vS) ,舒张期血流速度 (vD)和脉动指数 (PI)。结果 :A组伤前、后 5min、1 6 8hvS 与B组比较 ,差异无统计学意义 ;A组伤后 6h、72hvS((39.4 5± 7.5 )cm/s,(4 1 .2 0± 5 .94 )cm/s)与B组 ((5 1 .6 8± 1 0 .32 )cm/s,(5 2 .4 1± 8.5 6 )cm/s)比较差异有统计学意义 (P <0 .0 5 ) ;A组伤前、后 5min、1 6 8hvD 与B组比较 ,差异无统计学意义 ;A组伤后 6h、72hvD((2 6 .33± 3.4 6 )cm/s,(2 5 .84± 5 .6 9)cm/s)与B组 ((33.6 4± 4 .2 7)cm/s ,(34.86± 7.4 8)cm/s)比较差异有统计学意义 (P <0 .0 5 ) ;A组伤前、后 5minPI值与B组比较差异无统计学意义 ,A组伤后 6h、72h、1 6 8hPI(2 .0 6±0 .5 8,2 .2 5± 0 .36 ,1 .5 3± 0 .39)与B组 (1 .2 6± 0 .2 9,1 .38± 0 .2 9,0 .96± 0 .1 7)比较差异有统计学意义 (P <0 .0 5 )。结论 :提示右美沙芬可通过改善脑血流速度、降低脉动指  相似文献   
57.
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic.  相似文献   
58.
作者报告了10例室上性心动过速,共11条径路的射频消融的成功经验。介绍了左侧显性旁路、隐匿性旁路及房室结双径路射频导管改良的基本方法以及定位标准。  相似文献   
59.
制备了聚乙烯醇 (PVA)与聚苯乙烯磺酸 (PSSA)的共混膜 ,并研究了膜的组成、热处理温度、甲醇水溶液浓度等对膜电导率和甲醇透过率的影响。与目前普遍使用的NafionTM膜相比 ,这种由阻醇材料PVA与离子交换材料PSSA共混后形成的聚合物膜既能提高阻醇性能 ,又具有一定的电导率。一种以聚苯乙烯磺酸含量为 17%的膜 ,其电导率可达 3× 10 -3 S·cm-1,但甲醇透过率P仅为 2× 10 -8cm2 ·s-1。如果以σ/P为综合指标 ,则此膜的综合性能比NafionTM膜高约 4 0倍  相似文献   
60.
Rat spinal dorsal horn neurons in slice preparations perfused with Ringer solution containing 0.5-1 microM TTX and/or 10-20 mM tetraethylammonium at 29 degrees C, were studied by using a single microelectrode voltage-clamp technique. Slow persistent inward currents were recorded during depolarizing voltage commands to membrane potentials positive to about -40 mV. The inward current was depressed by removing external Ca, or by adding 0.1-0.2 mM Cd, 5 mM Co or 0.1 mM verapamil, and was increased by adding Ba or Bay-K 8644. Substance P (SP) augmented a persistent slow inward Ca-sensitive current in a dose-dependent manner. It is suggested that this effect may be instrumental in generating the SP-evoked slow depolarization, increase in membrane excitability, and the 'bursting' behavior in the immature rat dorsal horn neurons. In addition, in some neurons SP reduced the M-like current, which effect may contribute to, but not explain, generation of the SP-induced slow depolarization.  相似文献   
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