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The density of substance P (SP)-, calcitonin gene-related peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-immunoreactive (ir) nerve endings was quantitatively evaluated in intact and inflamed gastrocnemius-soleus muscle of the rat. In persistently inflamed muscle (12 days after a single injection of Freund’s adjuvant into the muscle), the density of SP-ir fibres was significantly increased. CGRP- and VIP-ir fibres displayed an insignificant increase in density. The density of fibres ir for nerve growth factor (NGF) and for growth-associated protein 43 (GAP-43/B-50), a marker for axonal sprouting, regeneration and synaptic reorganisation, increased significantly in persistently inflamed muscle. The data are consistent with the established contribution of NGF on the expression of SP and GAP-43 in afferent neurones under the influence of a persistent inflammation. Received: 8 September 1997 / Accepted: 12 February 1998  相似文献   
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Infection is the most important cause of mortality in leucopenic patients. A broad spectrum antibiotic therapy is imperative in febrile and neutropenic patients. In a multicentric study we have used ceftazidime (100 mg/kg/d) and netilmicin (6 mg/kg/d) in 88 children (fever greater than or equal to 38.5 degrees C, neutropenia less than 500/mm3) treated for acute leukemias (59), non Hodgkin lymphomas (13) or solid tumors (16). Median age was 7 years (2 months-16 years). In patients who continued to remain febrile, vancomycin (40 mg/kg/d) was added after 48 hours. The effective treatment was continued until a neutrophil count greater than 1,000/mm3. The first combination (ceftazidime + netilmicin) was effective in 64 children (73%) and the second combination (ceftazidime + netilmicin + vancomycin) in 11 patients. Bacteria were isolated in 39 children: Escherichia coli: 9, Staphylococcus epidermidis: 9, Staphylococcus aureus: 8, Streptococcus: 6, Pseudomonas aeruginosa: 3, Streptococcus pneumoniae: 1, Haemophilus: 1, Klebsiella pneumoniae: 1, Proteus: 1, Serratia: 1, Flavobacterium: 1. In these 39 patients, 30 became apyretic with ceftazidime and netilmicin and 6 after vancomycin. All blood culture were negative after the first combination. The median duration of antibiotic therapy was 14 days (5-9 days: 28, 10-20 days: 43, greater than 20 days: 17). There were no death, no superinfection. Tolerance was good without kidney or liver or biological perturbation. We conclude that the combination ceftazidime and netilmicin is effective in neutropenic children.  相似文献   
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Clinically significant pneumococcal isolates were prospectively collected from outpatients with respiratory tract infections by 19 different clinical microbiology laboratories in Germany. Resistance rates in a total of 961 isolates were as follows: penicillin, 6.6%; clarithromycin, 10.6%; tetracycline, 13.9%; and levofloxacin, 0.1%. Among 324 isolates from children, pneumococcal serotypes 19F (17.0%), 23F (13.0%), and 6B (11.7%) were the predominant types.  相似文献   
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In many European countries, the level of pneumococcal resistance to macrolides has now passed the level of resistance to penicillin G. A total of 82 erythromycin A-resistant isolates of Streptococcus pneumoniae were collected by 11 laboratories in seven European countries. All of the isolates were tested for antimicrobial susceptibility, analyzed for clonal relatedness by multilocus sequence typing, and characterized for macrolide resistance genotypes. The prevalence of the macrolide resistance genotypes varied substantially between countries. In France (87.5% of all strains), Spain (77.3%), Switzerland (80%), and Poland (100%), strains were predominantly erm(B) positive, whereas higher levels of mef(A)-positive strains were reported from Greece (100%) and Germany (33.3%). Macrolide resistance was caused by the oligoclonal spread of some multilocus sequence types, but significant differences in clonal distribution were noted between France and Spain, countries from which high levels of macrolide resistance have been reported. Overall, sequence type 81 (Spain23F-1 clone) was by far the most widespread. The mainly erm(B)-positive serotype 14 clone (sequence type 143), first reported in Poland in the mid-1990s, is now widespread in France.  相似文献   
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Caenorhabditis elegans let-7, a founding member of the microRNA family, is predicted to bind to six sites in the 3'UTR of the mRNA of its target gene, lin-41, to down-regulate LIN-41. Here, we demonstrate that wild-type let-7 microRNA binds in vitro to RNA from the lin-41 3'UTR. This interaction is dependent on two conserved let-7 complementary sites (LCSs). A 27-nucleotide sequence between the LCSs is also necessary for down-regulation in vivo. LCS mutations compensatory to the lesion in let-7(n2853) can partially restore lin-41 3'UTR function in a let-7(n2853) background, providing the first experimental evidence for an animal miRNA binding directly to its validated target in vivo.  相似文献   
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The oxygen consumption (VO2 microL/h/mg) of sham and of traumatized rat brains within 30 min and 6 h after a lateral fluid percussion injury (FPI) was measured with the Cartesian microrespirometer. Brain slices were cut at the plain of injury and site-specific 20-60-microg cores of tissue were transferred to the microrespirometer. In sham brains, the cortical VO2 (CVO2) was 13.78+/-0.64 and the hippocampal VO2 (HPVO2) was 11.20+/-0.58 microL/h/mg (p<0.05). Within 30 min of the injury, the respective values of 16.89+/-0.55 and 14.91+/-0.06 were significantly increased (p<0.05). The combined VO2 (CVO2, HPVO2) of 12.49+/-0.06 microL/h/mg in shams was significantly less than the combined VO2 of 15.90+/-0.59 microL/h/mg at 30 min post FPI (p<0.001). The maximal CVO2 of 19.49+/-1.10 microL/h/mg and the maximal HPVO2 of 15.98+/-0.99 microL/h/mg were both obtained from the ipsilateral side of the injury. Whereas the contralateral cortical value for injured brains was not significantly different from that of the shams, both ipsilateral and contralateral hippocampal values were significantly greater than that of the shams in response to injury (p<0.05). By 6 h postinjury, the combined VO2 had dropped to 10.01+/-0.84 microL/h/mg but was not significantly lower than the sham values. The data indicate that normal CVO2 is greater than normal HPVO2. The FPI produces significant increases in both CVO2 and HPVO2. Also, while the immediate increase in CVO2 appears to be injury-site dependent, that is, regional, the increase in HPVO2 appears to be global.  相似文献   
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回春液补肾助阳药效学的实验研究   总被引:2,自引:0,他引:2  
回春液由人参、鹿茸、貂鞭等名贵中药组成。有补肾助阳,填精益气等功效。药效学研究证实,该药有促进幼鼠发育及增加去势大鼠前列腺——精液囊的重量,亦显著增加小鼠血红蛋白的含量,表明回春液有雄性激素样作用。  相似文献   
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