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101.
Age-related changes in cortical porosity of the midshaft of the human femur   总被引:1,自引:1,他引:0  
Complete cross-sections from the femoral midshaft of 180 individuals of known height and weight, aged 21–97 y, from a modern Australian population were examined using automatic video image analysis to quantify total subperiosteal porosity (TSPP). More specifically, the aim was to investigate whether age changes were similar in both sexes in (1) total subperiosteal area (TSPA), cortical area (CA) and medullary area (MA), (2) intracortical porosity (ICP), and (3) the respective contributions to TSPP made by MA and intracortical void area (ICVA). Our findings indicated that both sexes showed a significantly greater height normalised TSPA in the 70s as compared with the 20s. Males had consistently larger bones with a greater height normalised CA. In both sexes CA showed a tendency to increase till the 7th decade and then to decline, more so in females. MA approximately trebled in females and doubled in males over the age range studied. Although ICP also increased, from 4–6% in young adults to over 9% in the elderly, it showed a significant difference between the sexes only in the 3rd decade, being greater in males at this stage. By contrast, TSPP became significantly greater in females (from that recorded in the 3rd decade) by the time they reached the 50s, while in males this did not occur till the 80s. It increased from ∼25% in young adults of both sexes to ∼50% in females and ∼37% in males in their 80s. However, in the elderly there was great variability in both sexes in the appearance of bones from individuals of similar chronological age. Some bones differed little from those in younger subjects, others showed greatly increased ICP, still others displayed reduced cortical widths with low ICP. The femoral midshaft resembles other skeletal sites in that age changes in TSPP are more marked in females than males.  相似文献   
102.
Single neuron activities in the lateral hypothalamic area (LHA) were recorded during bar press feeding task in the monkey. First registered neurons were sorted into 2 groups, glucose-sensitive (GS) and glucose-insensitive (GIS) neurons, depending on their glucose sensitivity. Then firing variations to feeding, electrophoretically applied catecholamines and opiate, and to odor and taste stimuli were investigated. GS neurons responded to dopamine, noradrenaline and morphine more often than GIS neurons. In feeding task GS neurons responded during bar press (BP) and reward (RW) periods with long-lasting inhibition of firing and at cue tone (CT) with transient inhibition, while GIS neurons responded during BP and RW periods mainly with excitation and at cue light (CL) with excitation. A majority of GS neurons responded to both odor and taste stimuli more often than GIS neurons. Data suggest that these two kinds of neurons in the LHA may be involved in different functional aspects of feeding: GS neurons, mainly in internal information processing and reward mechanism, and GIS neurons, in external information processing and motor aspects.  相似文献   
103.
目的 :探讨耕耘疗法在中小面积深度烧伤创面治疗中的疗效。方法 :对小面积深Ⅱ度~浅Ⅲ度烧伤创面进行了耕耘疗法 ,然后外用MEBO。结果 :治愈 16 5例 ,深Ⅱ度创面多在 17± 2 0天内愈合。浅Ⅲ度创面也在 2 8± 3 0天内愈合。结论 :通过采用耕耘方法可改善深度创面的局部微循环 ,尽快清除坏死组织 ,促进创面液化 ,充分发挥MEBO药效 ,使创面愈合期明显缩短 ,减少了疤痕率  相似文献   
104.
Previous functional magnetic resonance imaging (fMRI) studies suggest that motor system abnormalities are present in schizophrenia. However, these studies have often produced conflicting or ambiguous findings. The purpose of this study was to ascertain whether activation differences could be identified in stable schizophrenic patients on the basis of BOLD measures in two motor regions, the primary motor cortex, Brodmann area 4 (BA4) and the premotor and supplementary motor area, Brodmann area 6 (BA6). Twenty-one schizophrenic patients and 21 healthy control subjects were studied with BOLD fMRI methods during a sequential finger tapping task. Statistical parametric maps were generated for each subject, and anatomic regions were automatically defined using an anatomic atlas. Compared with controls, the schizophrenic patients showed a significant reduction in contralateral activation for both BA4 and BA6 (P<0.001), and in ipsilateral activation in BA4 (P=0.007) and BA6 (P=0.002). In healthy controls, the coactivation in the ipsilateral cortex is reduced in comparison with the contralateral cortex for right and left handed tasks. In BA4, this reduction is significant for right (P=0.007) and left (P=0.003) finger tapping. Similar results were obtained for BA6. Further analyses are necessary to evaluate the activation in other motor system regions.  相似文献   
105.
六十年代以来,区域研究与地方史理论在美国汉学界开始流行。文章试图在全面厘清汉学区域研究及地方史视角兴起原因的基础上,分析这一现象在思想文化研究中的利弊得失,以期展现中国研究的复杂性并反思我们引进海外汉学成果时的态度。  相似文献   
106.
The spatial and temporal pattern of expression of the protein products of immediate early genes (IEGs) c-fos, fos B, and egr-1 were mapped in medial preoptic area (MPOA) and ventral bed nucleus of stria terminalis (VBST) during maternal behavior in rats. Immunocytochemical analysis indicated significant increases in the number of cells expressing c-Fos after 2 h of pup exposure, while Fos B levels showed a delayed response, reaching maximal levels after 6 h.  相似文献   
107.
A 9-month-old male infant had generalized diffuse blue-gray pigmentation over most of his body, sparing the scalp, face, neck, palms, soles, periumbilical area, genital area, and nipples. Within the lesion, there were several conspicuous macules of considerably darker hue. Histologic examination revealed numerous dermal melanocytes. By 16 months of age, the child's blue-gray pigmentation had decreased substantially.  相似文献   
108.
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray (PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro). Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat) into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7 nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan (3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii) the close relationship between glutamate and vasopressin in the central blood pressure regulation. Received: 1 April 1997 / Accepted: 2 February 1998  相似文献   
109.
Summary Muscle force recovery from short term intense exercise was examined in 16 physically active men. They performed 50 consecutive maximal voluntary knee extensions. Following a 40-s rest period five additional maximal contractions were executed. The decrease in torque during the 50 contractions and the peak torque during the five contractions relative to initial torque were used as indices for fatigue and recovery, respectively. Venous blood samples were collected repeatedly up to 8 min post exercise for subsequent lactate analyses. Muscle biopsies were obtained from m. vastus lateralis and analysed for fiber type composition, fiber area, and capillary density. Peak torque decreased 67 (range 47–82%) as a result of the repeated contractions. Following recovery, peak torque averaged 70 (47–86%) of the initial value. Lactate concentration after the 50 contractions was 2.9±1.3 mmol·l−1 and the peak post exercise value averaged 8.7±2.1 mmol·l−1. Fatigue and recovery respectively were correlated with capillary density (r=−0.71 and 0.69) but not with fiber type distribution. A relationship was demonstrated between capillary density and post exercise/peak post exercise blood lactate concentration (r=0.64). Based on the present findings it is suggested that lactate elimination from the exercising muscle is partly dependent upon the capillary supply and subsequently influences the rate of muscle force recovery. Dr. Tesch was on leave from Department of Clinical Physiology, Karolinska Hospital, Stockholm, Sweden  相似文献   
110.
Objectives: To assess the efficacy and tolerability of a new matrix patch delivering 0.05 mg estradiol per day (Estraderm MX 50) in postmenopausal women with moderate to severe postmenopausal symptoms. Methods: A multicenter, double-blin, randomized, between-patient, placebo controlled trial in 109 postmenopausal women was carried out. Patches were applied twice weekly for 12 weeks. Patients were assessed at 4, 8 and 12 weeks of treatment. The primary efficacy variable was change from baseline in mean number of moderate to severe hot flushes (including night sweats) per 24 h during the last 2 weeks of treatment. Other variables included Kupperman Index, local and systemic tolerability. Plasma concentrations of estradiol (E2), estrone (E1) and estrone sulfate (E1S) were determined before and after treatment. Results: Estraderm MX was significantly superior to placebo (P < 0.001) in reducing mean number of moderate to severe hot flushes (including night sweats) per 24 h after 4, 8 and 12 weeks of treatment. The estimate of treatment group differences after 12 weeks was 4.2 hot flushes (95% confidence interval: 2.6–5.5). Estraderm MX also significantly reduced Kupperman Index at all time points compared to placebo (P < 0.001). Estraderm MX induced increases in mean E2, E1 and E1S plasma levels as expected (E2: baseline 2.7 pg/ml, 12 weeks 38.9 pg/ml; E1: baseline 18.8 pg/ml, 12 weeks 41.6 pg/ml; E1S: baseline 235.6 pg/ml, 12 weeks 765.1 pg/ml). Overall rates of adverse experiences were similar for Estraderm MX and placebo. The number of patients reporting skin irritation was low and similar in both groups. Conclusions: Estraderm MX 50, a new matrix patch, offers an effective and well tolerated dosage form for transdermal delivery of 0.05 mg E2 per day.  相似文献   
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