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71.
Y P Wu  G R Wang  J P Sha  L G Wang  N X Qu  C Y Lu  Y M Yu 《Biorheology》1988,25(1-2):77-83
We have used hydroelastic waves to treat the closed trauma of the soft tissue. The Shu Huo Jiu (S. H. J.) which is the Chinese traditional medicine alcohol, was used as the fluid medium for generating the pressure waves. The biomechanical model was established and analysed. Both animal and human tests have been made. A practical system was designed, constructed and clinically tested to treat the closed trauma, such as the bruise, contusion, sprain etc.. This system was found to be effective.  相似文献   
72.
Intrathymic, Ia-bearing antigen-presenting cells (APC) are believed to play an important role in the development of a mature, functional T-cell repertoire. We used chronic in vivo treatment of neonatal mice with anti-I-A monoclonal Ab (MAb) to examine the expression of I-A and I-E antigens on intrathymic and peripheral APC. Three weeks after continuous treatment with anti-I-A MAb, FACS analysis of unfractionated spleen cells revealed a 75-90% reduction in the number of I-A bearing cells. Splenic antigen-presenting capacity measured by the ability of unseparated or density gradient-enriched APC to stimulate I-A- or I-E-reactive T-cell hybridomas was also greatly reduced. In contrast to the expression of I-A and I-E molecules in the splenic APC, anti-I-A MAb treatment resulted in decreased thymic APC I-A expression without significant changes in I-E as measured by FACS analysis. This was confirmed in functional studies in which allo-I-A- or auto-I-A-reactive T-cell hybridomas could not be stimulated by treated thymic APC. Unlike splenic APC, anti-I-A-treated thymic APC did not differ significantly from normals in their ability to stimulate allo-I-E-reactive T hybridomas. This lack of linkage or comodulation of I-A and I-E expression on thymic but not splenic APC may allow us to study the role of I-A molecules and I-E molecules on the development and expansion of functional, mature T-cell repertoires.  相似文献   
73.
绿尾虹雉生态学研究   总被引:16,自引:0,他引:16  
绿尾虹雉Lophophorus lhuysti生态和生物学研究是中国科学院重点科研课题——“中国珍稀濒危难类生态生物学”——部分工作。 本文为作者对绿尾虹雉所作的生态和生物学系统研究首次报道。绿尾虹雉主要牺息于海拔3,500—4,000米亚高山灌丛和草甸。杂食性鸟类,以植物性食物为主,亦食昆虫。营巢于岩洞或灌丛地面上,每窝产3—4,多达11枚卵。种群密度1.32—1.58只/km~2。目前数量急剧下降,处于濒危,急待保护。  相似文献   
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75.
Phosphorylation of ankyrin decreases its affinity for spectrin tetramer   总被引:5,自引:0,他引:5  
The effects of phosphorylation on the interaction between spectrin and ankyrin were investigated. Spectrin and ankyrin were phosphorylated using purified human erythrocyte membrane and cytosolic (casein kinase A) kinases. These two kinases have similar properties as well as activities toward spectrin and ankyrin. Both kinases catalyzed the incorporation of about 2 mol of phosphate/mol of spectrin and about 7 mol of phosphate/mol of ankyrin. These phosphates were incorporated primarily into seryl and threonyl residues of the proteins. The phosphopeptide maps of ankyrin phosphorylated by the membrane kinase and casein kinase A were identical. Binding studies indicate that ankyrin exhibits different affinities for spectrin dimers (KD = 2.5 +/- 0.9 X 10(-6) M) and tetramers (KD = 2.7 +/- 0.8 X 10(-7) M). These dissociation constants were not appreciably affected by the phosphorylation of spectrin. On the other hand, phosphorylation of ankyrin was found to significantly reduce its affinity for either phosphorylated or unphosphorylated spectrin tetramers (KD = 1.2 +/- 0.1 X 10(-6) M) but not spectrin dimers (KD = 2.5 +/- 0.4 X 10(-6) M). The same results were obtained using either the membrane kinase or casein kinase A as the phosphorylating enzyme. The above observation suggests that ankyrin phosphorylation may provide an important mechanism for the regulation of the erythrocyte membrane cytoskeletal network.  相似文献   
76.
To examine the effects of prepubertal steroid environment on subsequent estrous cyclicity and gonadotropin secretion, Silastic implants containing 25, 50 or 100% 17 beta-estradiol (E2;n=34), 50% diethylstilbestrol (DES; n=16) or 50% testosterone (T; n=17) were placed into female rats at 12 days of age and removed on the day of vaginal opening (18-24 days of age). At 80 days of age, the percentages of regularly cycling females in the E2-(three groups combined), DES- and T-implanted groups were 59%, 0% and 59%, respectively. By 110 days of age, the percentages were reduced to 24%, 0% and 0%, and at 140 days of age 6%, 0% and 0%, respectively. Many of these females displayed irregular estrous cycles followed by a persistent estrous (PE) state. By contrast, 89% of the control females (blank implants or no implant) maintained regular cycles up to 140 days of age. At 150 days of age, an i.p. injection of gonadotropin-releasing hormone (GnRH; 100 ng/100 g BW) markedly increased serum luteinizing hormone (LH), but not follicle-stimulating hormone (FSH), in intact PE females treated prepubertally with E2 implants. After the test with GnRH, PE rats were ovariectomized (OVX). Thirty days after OVX, similar GnRH administration significantly increased serum levels of both LH and FSH, but these responses were significantly (P less than 0.01) reduced when compared with those in OVX controls. Progesterone administration to estradiol benzoate-primed, acutely (3 days) OVX, or long-term (43 days) OVX-PE females did not increase LH or FSH release. These results indicate that exposure to exogenous estrogen or T prior to puberty precipitates the decline in estrous cyclicity associated with the loss of gonadotropin surge response, presumably due to an alteration in hypothalamic GnRH release.  相似文献   
77.
含有E.coli galK和gpt基因的重组DNA pPB22用显微注射法导入昆明白小鼠受精卵,经发育,最后得到21只成年小鼠。其中1只小鼠的肝脏显示出E.coli gpt酶活性,但未检测出E.coli galK酶活性。印迹分子杂交表明,外源的pPB 22重组DNA已整合到2只小鼠的染色体上,其中包括那只肝脏中显示E.coli gpt酶活性的小鼠。  相似文献   
78.
The beta-adrenergic agonist 1-isoproterenol evokes an acute (less than 5 min) stimulation of endocytosis, hexose transport and amino acid transport, measured by the temperature-sensitive uptake of HRP, 3H-DG and 14C-AIB, in mouse kidney cortex slices. This stimulation is concentration dependent and is maximal at 10(-8)-10(-7) M isoproterenol. Peroxidase cytochemistry showed that the hormonal increase in HRP uptake is confined to proximal tubules. The rapid membrane response is abolished in a calcium-free medium and by the beta-adrenergic antagonist propranolol, indicating Ca2+- and beta-adrenoreceptor-dependence. Isoproterenol (1 microM) rapidly (less than 30 sec) stimulates the influx and efflux of 45Ca in cortex slices. Isoproterenol also decreased mitochondrial 45Ca and increased soluble 45Ca. These results indicate that beta-adrenergic stimulation of membrane transport functions involves an increased influx of extracellular calcium and a mobilization of intracellular (mitochondrial) calcium. An increase in cytosolic Ca2+ concentration appears to be the regulatory signal for these membrane transport processes.  相似文献   
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