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1.
The purpose of this investigation was to determine whether the presence of selected disease-associated bacteria in health-associated plaque correlated with future gingivitis. Sites of periodontal health were identified in 65 adults. Six months later (recall 1) plaque was collected from sites that remained in periodontal health, and 5 species of specific bacteria and pathogen-related oral spirochetes were detected using monoclonal antibodies in a microscopic assay. Members of the spirochete morphogroup were also identified by phase contrast microscopy. The relationship between site-specific detection of bacteria at recall 1 and development of gingivitis at recall 2 or 3 was evaluated by means of logistic regression using generalized estimating equations, from which odds ratios (OR) were estimated. Significance was conservatively defined as OR > 2.0 and P < 0.05. We found that 488 of 1,424 healthy sites developed gingivitis over the 12-month interval between recall 1 and 3. Only the spirochete morphogroup (OR =2.04; P=0.002) was significantly associated with the transition from health to gingivitis. The association of Treponema socranskii with future gingivitis was higher than expected (OR=2.27), but the relationship was not statistically significant (P=0.163). Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, and pathogen-related oral spirochetes did not correlate well with gingivitis (OR < 2.0). Health-associated plaque from 5 sites contained Treponema denticola, and all 5 sites progressed to gingivitis. An OR could not be calculated because T. denticola was not detected in health-associated plaque from stable healthy sites. These findings indicated that the presence of T. denticola and unidentified spirochetes in health-associated plaque was associated with increased susceptibility to gingival inflammation. Future studies assessing a larger panel of dental plaque microorganisms, with shorter intervals between baseline and follow-up assessment, are necessary to more fully evaluate the association between detection of specific organisms at healthy sites and risk for gingivitis.  相似文献   
2.
The experiment reports the effects of appropriate and inappropriate instructions and 2 drugs (.5 g chloral hydrate and 10 mg racemic amphetamine sulphate) on motor performance and mood measures. The Ss were 90 older men randomly assigned to 9 experimental groups. The design used was expansion of a model design involving Drug Disguised groups, Placebo groups (300 mg lactose), an Untreated group, and Amphetamine, Chloral Hydrate, and Neutral instructions. The drugs and placebos were given to the Ss in capsules, and all Ss received orange juice, which was also the vehicle for the disguise. The Untreated group received orange juice only. Instructions alone affected performance, but had little or no effect on mood. Instructions appropriate to the presumed drug effects produced performance deterioration on the simple motor tasks used. Instructions inappropriate to the presumed drug effects counteracted much of the drug produced decrement. A slight decrement in performance was found in the Placebo group which received Amphetamine instruction. Amphetamine treated Ss produced reports of greater comfort on the mood index than did chloral hydrate. On the other hand, the chloral hydrate instructions resulted in greater comfort than the Amphetamine instructions. There was no interaction between drug effects and instructional effects. The 2 Placebo groups did not differ significantly on the mood index. The effects of instructions on mood were found only when the drug was present. Several suggestions are offered for further research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Recombinant Clostridium difficile glutamate dehydrogenase (L-glutamate:NAD oxidoreductase, EC 1.4.1.2) was purified 177-fold to electrophoretic homogeneity with a 62% recovery through a four-step procedure involving gel filtration and ion-exchange and dye affinity chromatography. The approximate molecular weights of the native enzyme by gel filtration and subunits by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were consistent with a hexameric structure for the purified enzyme. The enzyme-catalyzed glutamate oxidation was an NAD-dependent sequential process in which NADP could not be substituted as coenzyme. Several dinucleotide analogs of NAD structurally altered in either the pyridine or the purine moiety were observed to function as coenzymes when substituted for NAD. Nicotinamide mononucleotide did not serve as a coenzyme for glutamate oxidation. Product inhibition by NADH was competitive with respect to NAD. In deadend inhibition studies, adenosine diphosphoribose was shown to be an effective coenzyme-competitive inhibitor.  相似文献   
4.
Entamoeba histolytica causes invasive amebiasis, a major parasitic disease of the developing world, whose primary symptoms are liver abscess and colitis. All strains of E. histolytica express a 260-kDa surface Gal/GalNAc lectin that is antigenically conserved and immunogenic. The lectin is required for adherence to human intestinal epithelial cells and contact-dependent killing of immune effector cells. By expression cloning, the carbohydrate recognition domain (CRD) was identified within the lectin heavy-subunit cysteine-rich region. Of interest for a hepatic parasite, the CRD had sequence identity to the receptor-binding domain of hepatocyte growth factor (HGF) and competed with HGF for binding to the c-Met HGF receptor. In an animal model of invasive disease, immunization with the CRD inhibited liver-abscess formation, yet in humans, a naturally acquired immune response against the CRD did not persist.  相似文献   
5.
The potential role of alpha2-adrenoceptors in modulating the activity of adenylyl cyclase in the rat striatum was examined. The selective alpha2-adrenoceptor agonist, UK14,304, produced a concentration-dependent inhibition of forskolin-stimulated accumulation of cAMP in striatal slices. The effect of UK14,304 was reversed by pre-incubation of striatal slices with the selective alpha2-adrenoceptor antagonist, RX821002. To determine whether alpha2C-adrenoceptors contribute to the alpha2-adrenoceptor-induced inhibition of forskolin-stimulated cAMP accumulation, an antisense oligodeoxynucleotide directed against alpha2C-adrenoceptor mRNA (alpha(2C)AS) or a random sequence (RS) was infused directly into the striatum. The ability of alpha(2C)AS to reduce the expression of alpha2C-adrenoceptors has been previously demonstrated. Alpha2C(AS) infusions did not reduce the ability of UK14,304 to inhibit forskolin-stimulated cAMP accumulation. Instead, alpha(2C)AS significantly enhanced forskolin-stimulated cAMP accumulation on the infusion side compared to the contralateral striatum. In contrast to the effects of alpha(2C)AS, infusions of RS had no effects on forskolin-stimulated cAMP accumulation or on the ability of UK14,304 to inhibit this effect. Incubation of striatal slices from untreated rats with RX821002 could mimic the ability of alpha(2C)AS infusion to enhance forskolin-stimulated cAMP accumulation, and did so in a concentration-dependent manner. Alpha2-adrenoceptors are negatively coupled to adenylyl cyclase in the rat striatum and alpha2C-adrenoceptors appear to be under tonic activation by an endogenous ligand in striatal slices.  相似文献   
6.
The prevalence of infection by the invasive parasite Entamoeba histolytica and the noninvasive parasite Entamoeba dispar was determined in 2000 children in Bangladesh. Antigen detection identified more cases of E. histolytica-E. dispar infection than did culture or microscopy. Microscopic identification of E. histolytica-E. dispar complex infection in stool did not equate with the diagnosis of amebic dysentery because most amebic infections in this population were due to E. dispar: Urban children with diarrhea had a 4.2% prevalence of E. histolytica infection and a 6.5% prevalence of E. dispar infection; rural asymptomatic children had a 1.0% prevalence of E. histolytica infection and a 7.0% prevalence of E. dispar infection. Shigella dysenteriae and Shigella flexneri infections were more frequent in children who also had Entamoeba infection, a potentially important consideration for the empiric treatment of dysentery in this population.  相似文献   
7.
A Giardia lamblia antigen detected by the TechLab Giardia Test (TechLab, Inc., Blacksburg, Va.) and the Alexon ProSpecT Giardia microplate assay (Alexon, Inc., Sunnyvale, Calif.) was purified by immunoaffinity chromatography from supernatant fluids of encystment cultures. Two major proteins (Mr 22,000 and 26,000) were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Coomassie staining that did not resemble the GSA65 antigen reportedly detected by the Alexon test. These proteins reacted intensely with the monoclonal antibodies used in both commercial enzyme-linked immunosorbent assays (ELISAs). Both proteins had identical N-terminal amino acid sequences and were identified as cyst wall protein 1 (CWP1). The 26-kDa form appeared early during encystment followed by the appearance of the 22-kDa form. Recombinant CWP1 (Mr 26,000) was strongly positive in both commercial tests. CWP1 was stable in human stool specimens, resistant to degradation by proteases and N- and O-glycanases, and unaffected by oxidation with sodium periodate. Two minor proteins with Mrs of 32,000 and 39,000 were detected in CWP1 preparations by using a sensitive fluorescent protein stain. Both were identified as CWP2, and neither reacted with the monoclonal antibodies from the commercial tests. We analyzed 535 stool specimens for CWP1 by using both commercial ELISAs and resolved discrepant results by using routine ova and parasite examination (O&P) and on immunofluorescence antibody assay. The presence of CWP1 correlated well between both ELISAs (98.7% correlation). Our results demonstrate that both commercial ELISAs detect CWP1, which is a useful diagnostic marker because it is highly stable, is secreted in large amounts by encysting trophozoites, and correlates well with O&P.  相似文献   
8.
In the US over one million persons are currently infected with the HIV, over half a million have had AIDS, and over 300,000 have died from AIDS. Worldwide, it is estimated that more than 17 million people are currently infected with HIV, and over 1,200,000 cases of AIDS have been reported to the World Health Organization. By some estimates, up to 40% of patients with AIDS will ultimately develop some form of cancer. Non-Hodgkin's lymphoma, Kaposi's sarcoma and invasive cervical cancer have a higher incidence in persons with HIV infection and all three are AIDS-defining illnesses. In addition, several reports suggest that a number of other malignancies may occur at an increased incidence in persons with HIV infection, including squamous-cell carcinoma of the head, neck and anus, plasmacytoma, melanoma, small-cell lung cancer, basal-cell cancer, and germ-cell tumours. Clinicians should become familiar with HIV-related malignancies as their incidence is expected to further increase as more effective therapies for HIV and associated opportunistic infections allow patients to live longer in an advanced state of immunodeficiency. In the current article, we will review the clinical and therapeutic aspects of the most common AIDS-related malignancies including non-Hodgkin's and Hodgkin's lymphomas, Kaposi's sarcoma and anogenital epithelial neoplasias.  相似文献   
9.
Comments on D. G. Barker's (1966) article on the correlation of economic, educational, and other demographic variables with the number of psychologists per 100,000 population over the 48 contiguous states. A reply by Barker follows. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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