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101.
102.
Third-instar German cockroach nymphs were held to maturity in continuous proximity to test surfaces treated with hydroprene and fenoxycarb, which they were unable to contact directly. Surfaces tested were unfinished plywood, fiberboard, vinyl tile (absorbent surfaces), glass, stainless steel, ceramic tile, and formica (nonabsorbent surfaces). Number of oothecae, percent egg hatch, and survival did not differ between any fenoxycarb treatment and the untreated controls, but there was significant wing twisting (76-94%) for all nonabsorbent surfaces. Number of oothecae was significantly lower and percent wing twisting was significantly higher for all hydroprene-treated surfaces with respect to the untreated controls, although survival was not affected. These effects were less pronounced for the nonabsorbent surfaces. These results indicate that hydroprene, but not fenoxycarb, has significant biological activity through volatile action when applied at current label rates. This activity is likely to have important consequences for control, especially for "crack and crevice" applications in confined spaces.  相似文献   
103.
Summary In bovine -mannosidosis, the thyroid in the affected newborn shows marked cytoplasmic vacuolation. There is an associated reduction in the serum concentrations of thyroxine and tri-iodothyronine.  相似文献   
104.
105.
Summary Staining reactions for a number of histochemical procedures for lipophilic staining and protein were studied in the enamel matrix along the length of rat incisors. Sudan Black gave a positive stain across the whole thickness of very early enamel (up to 30 m) but this staining only continued as a narrow band close to the ameloblasts as the enamel matured. A variety of tests for protein produced almost identical staining patterns in enamel matrix up to 100 m thick. Since the pattern of lipid staining persisted, after using a number of procedures which could normally be expected to remove lipid, it is suggested that Sudan Black positive staining may be due to lipophilic protein rather than lipid itself. Fluoride did not significantly alter the staining reactions for lipid and protein but did proceduce matrix which was much more effectively stained by cross-linking agents FFDNB and FF sulphene.  相似文献   
106.
An influential theory of long-term memory, in which new episodic learning is dependent upon the integrity of semantic memory, predicts that a double dissociation between episodic and semantic memory is not possible in new learning. Contrary to this view, we found, in two separate experiments, that patients with impaired semantic memory showed relatively preserved performance on tests of recognition memory if the stimuli were perceptually identical between learning and test. A significant effect of semantic memory was only seen when a perceptual manipulation was introduced in the episodic task. To account for these findings, we propose a revision to current models of long-term memory, in which sensory/perceptual information and semantic memory work in concert to support new learning.  相似文献   
107.
Kinematics of the scaphotrapezio-trapezoidal joint during wrist flexion/extension motion (FEM) and radial/ulnar deviation (RUD) was investigated using a 3-dimensional dynamic motion analysis system. The scaphoid/trapezoid motion was found to be a rotational motion obliquely oriented relative to the sagittal plane of the wrist and described in an ulnoflexion/radial extension motion plane in both FEM and RUD of the wrist. The axis of rotation of the scaphoid/trapezoid motion during both FEM and RUD wrist motions was essentially the same and runs through the radiopalmar aspect of the distal scaphoid and the waist of the capitate. Motion analysis also revealed that the trapezium-trapezoid and trapezoid-capitate joints are essentially immobile. Hence, the scaphotrapezio-trapezoidal motion is considered to be a single degree of freedom that is essentially the same in both FEM and RUD of the wrist.  相似文献   
108.
益母草的化学、药理和临床研究进展   总被引:50,自引:0,他引:50  
阮金兰  杜俊蓉  曾庆忠  钱忠明 《中草药》2003,34(11):1069-1073
查阅近20年有关文献,对益母草的化学成分、药理作用、临床应用研究进展进行综述。益母草主要含有生物碱类、黄酮类、二萜类、脂肪酸类、挥发油类等化合物;药理作用研究证明其具有调经止血、保护心肌缺血再灌注损伤、抗血小板聚集、降低血液黏度等作用;在临床上常用来治疗流产后出血、冠心病、心肌缺血、高黏血症、痛经等疾病。益母草具有广泛的药理活性,对其药效学物质基础进行深入研究和开发,将具有重要意义。  相似文献   
109.
Twenty-two consecutive patients (23 wrists) underwent open reduction internal fixation of dorsal perilunate dislocations and fracture-dislocations through combined dorsal and volar approaches. One of 5 experienced wrist surgeons performed these procedures within an average of 3 days of injury (range, 0-26 days) and intercarpal fixation was kept within the proximal carpal row. Motion was instituted an average of 10 weeks (range, 5-16 weeks) after injury. All patients were males. The average age at the time of injury was 32 years (range, 16-60 years). The average follow-up period was 37 months (range, 13-65 months). Average flexion-extension motion arc and grip strength in the injured wrist were 57% and 73%, respectively, compared with the contralateral wrist. The scapholunate angle increased and the revised carpal height ratio decreased over time, which was statistically significant for both measurements. Three patients (3 wrists) required wrist arthrodesis and a fourth patient had an immediate scaphoid excision and 4-corner arthrodesis secondary to an irreparable scaphoid fracture. One patient required a proximal row carpectomy to treat septic arthritis. Nine of the remaining 18 wrists had radiographic evidence of arthritis, most often at the capitolunate or scaphocapitate articulations. Short form-36 mental summary scores were significantly greater than age- and gender-matched US population values; physical summary scores were significantly less. The disabilities of arm, shoulder, and hand evaluation, Mayo wrist score, and patient-rated wrist evaluation all reflected loss of function. Seventy-three percent of all patients had returned to full duties in their usual occupations and a total of 82% were employed.  相似文献   
110.
The mechanism responsible for insulin resistance during pregnancy remains unclear. Considerable evidence indicates that insulin receptor substrate-1 could play an important role in insulin sensitivity. It seems possible that the gestational hormonal milieu could affect insulin receptor substrate-1. In the present study, measurements of tyrosine phosphorylation and protein content of insulin receptor substrate-1 and gene expression in the liver, skeletal muscle and adipose tissue in the rat indicated that, during pregnancy, significant changes occurred in these parameters. We found in early gestation that muscle and adipose tissue were highly sensitive to insulin action, because the phosphorylation of insulin receptor substrate-1 is greater than in late gestation. However, in late gestation the tissue most sensitive to insulin action, reflecting insulin receptor substrate-1 phosphorylation, was the liver. Our hypothesis was that these results are connected with the changes in concentrations of estradiol and progesterone observed during pregnancy. It was concluded that the present findings demonstrate that different concentrations of gestational hormones play an important role in insulin sensitivity in this period, and that each tissue responds in the most appropriate manner to guarantee the gestation in its entirety, controlling the phosphorylation of insulin receptor substrate-1 in response to insulin receptor activation.  相似文献   
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