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Summary Conditioning therapy with aggressive chemotherapy and irradiation induces a state of transient combined immunodeficiency in bonemarrow transplant recipients. This promotes the occurrence of severe cytomegalovirus (CMV) infections, the most frequent lethal complication after bone-marrow transplantation (BMT) at present.Forty-four BMT recipients received CMV-IgG-hyperimmunoglobulin for CMV prophylaxis intravenously. The efficacy of this prophylaxis and possible risk factors for the occurrence of CMV-induced interstitial pneumonia (IP) were analyzed. Risk factors for the promotion of a CMV-IP were: additional immunosuppressive therapy after BMT, CMV-positive serostatus of the recipient, CMV-seropositive granulocyte transfusion, CMV infection immediately prior to BMT, and HLA-haploidentical BMT. In this study the incidence of graftversus-host disease was low and was not associated with the incidence of CMV infections. The use of T-cell-depleted grafts did not result in increased CMV infections or IP and may possibly have improved the immunological reconstitution.Abbreviations BMT Bone-marrow transplantation - CMV Cytomegalovirus - CMV-IG CMV-IgG-hyperimmunoglobulin - GvHD Graft-versus-host disease - IP Interstitial pneumonia - IS Immunosuppressive therapy  相似文献   
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Recently, chronic Aristolochia poisoning was found responsible for the aetiology of Balkan endemic nephropathy (BEN) in Croatia, Serbia, and Bosnia, and diet was the likely route of exposure to aristolochic acid (AA). BEN, often associated with an increased incidence of upper urinary tract carcinoma (UUC), also affects residents of certain rural villages in Romania. AA is a nephrotoxin and human carcinogen that forms DNA adducts after metabolic activation, which induce characteristic TP53 mutations in urothelial tumours. Here we present the first evidence linking AA exposure to UUC in residents of an endemic region in the Romanian Mehedinti County. DNA was extracted from kidney and tumour tissue of seven patients who underwent nephroureterectomy for UUC and resided in BEN villages (endemic group). Five patients with UUC from nonendemic villages served as controls. AA‐DNA adducts (7‐(deoxyadenosin‐N6‐yl)‐aristolactam I), established biomarkers of AA exposure, were identified by 32P‐postlabelling in renal DNA of six patients from the endemic group and in one of the nonendemic group (adduct levels ranged from 0.3 to 6.5 adducts per 108 nucleotides). Additionally, an A to T transversion in TP53, a base substitution characteristic of AA mutagenic activity was found in urothelial tumour DNA of one patient from the endemic group. Our results provide a molecular link to the cause of urothelial tumours in BEN regions of Romania indicating that AA is the common aetiological agent for BEN across its numerous geographical foci. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Objectives. We examined the association between influenza outbreaks in 83 metropolitan areas and credit card and mortgage defaults, as measured in quarterly zip code–level credit data over the period of 2004 to 2012.Methods. We used ordinary least squares, fixed effects, and 2-stage least squares instrumental variables regression strategies to examine the relationship between influenza-related Google searches and 30-, 60-, and 90-day credit card and mortgage delinquency rates.Results. We found that a proxy for influenza outbreaks is associated with a small but statistically significant increase in credit card and mortgage default rates, net of other factors. These effects are largest for 90-day defaults, suggesting that influenza outbreaks have a disproportionate impact on vulnerable borrowers who are already behind on their payments.Conclusions. Overall, it appears there is a relationship between exogenous health shocks (such as influenza) and credit default. The results suggest that consumer finances could benefit from policies that aim to reduce the financial shocks of illness, particularly for vulnerable borrowers.Seasonal influenza is a viral airborne disease that generally spreads each fall and winter, causing an estimated 1.5 million people to get sick and 200 000 to be hospitalized in a typical year in the United States.1,2 Symptoms can range from mild and hardly distinguishable from a common cold to severe and life-threatening. Influenza accounts for at least 500 000 deaths in the United States in the past 3 decades.3For employed individuals, influenza can make attending work difficult, because of either personal illness or caring for sick household members. This generates significant costs to employers and employees. Estimates from 2007 suggest that annual influenza outbreaks lead to $16.3 billion in lost productivity and wages, and $10.4 billion in medical costs,4 although these costs vary considerably across place.5Although there is a robust literature on the economic costs of influenza, we know little about how such unexpected health shocks are associated with other aspects of the economy, such as loan defaults. We built on existing knowledge of the economic costs of influenza by examining how influenza outbreaks influence credit card and mortgage default rates in US cities.In the wake of the Great Recession, loan defaults have increased, with negative financial consequences for families.6 For loans due on a monthly basis, such as mortgages and credit cards, past-due balances and late fees accumulate each month. Three missed payments (90-day delinquent) is a signal of a loan at high risk for failure and in most states triggers legal collections processes.7In the microeconomic literature, illness is seen as a shock—an unexpected event—that can affect household income and expenses. If the shock results in a disruption to income, households will respond with shifts in consumption and expenditure patterns.8 We contend that influenza, as a health shock, has the potential to trigger loan default by constraining a family’s budget because of personal illness or caretaking burdens. Influenza may also trigger inattention to household financial management and a lack of planning for future bill payments.9–11 This may be especially problematic for borrowers who are already behind on their payments, whom we define as vulnerable borrowers. For these borrowers, who also tend to be economically vulnerable and disadvantaged in other ways,12,13 an influenza outbreak could increase the likelihood of further missed payments. A recent study supports this notion, and shows that economically vulnerable households are more likely to borrow and borrow more in the event of a health shock than less vulnerable households.14 However, this study did not examine credit default.A growing literature examines the complex and potentially multidirectional relationship between health and default.15–19 Most research examines whether defaults influence health,15,19,20 and less examines how health may have an impact on default risk.21 However, a key problem inherent in this literature is that health status is endogenous, and it is difficult if not impossible to disentangle processes of causation, selection, and reverse causation with survey data.Our interest in influenza provides us with a unique opportunity to improve causal estimates of health shocks on default. Influenza occurs to varying degrees in every city and year in the United States, and the intensity of the outbreak is an ostensibly exogenous health shock for communities. Thus, influenza outbreaks provide a natural experiment in which we use variation in influenza severity across time and place to identify the effects of a particular health shock on default. Specifically, we ask whether influenza outbreaks in US metropolitan statistical areas (MSAs) are associated with defaults from the first quarter (March) of 2004 (Q1 2004) to the second quarter (June) of 2012 (Q2 2012).We make 3 contributions with this study. First, we extended the literature on the economic costs of influenza. Second, we contributed to the literature on health shocks and default by providing a stronger test of the potential causal impacts of health shocks on loan default. Third, we considered whether effects vary across types of default, including 30-, 60-, and 90-day defaults. We predicted that influenza may have the greatest effect on borrowers who are already in default, such that the association between influenza and default should be stronger for borrowers who are farther behind.  相似文献   
5.
Journal of Thrombosis and Thrombolysis - The role of the A>G polymorphism at position 19911 in the prothrombin gene (factor [F] 2 at rs3136516) as a risk factor for venous thromboembolism...  相似文献   
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Synthetic oligonucleotides (18-mers) containing either a singledeoxyadenosine residue or a single deoxyguanosine residue weretreated with aristolochic acid I (AAI) or aristolochic acidII (AAII), the main components of theplant carcinogen aristolochicacid (AA). These reactions resulted in the formation of site-specificallyadducted oligonucleotides containing the two known AAI—DNAadducts (dA—AAI, dG—AAI) or the two known AAII—DNAadducts (dA—AAII, dG—AAII) at position 15 from the3'end. Using HPLC chromatography, the oligonucleotides werepurified and subsequently shown to contain the adducts of interestby 32P-postlabelling. The adducted oligonucleotides were usedas templates in primer (11-mer) extension reactions catalysedby modified bacteriophage T7 DNA polymerase (Sequenase). Regardlessof the type of DNA adduct examined, DNA synthesis was blockedpredominantly (80–90%) at the nucleotide 3' to each adduct,although primer extension to the full length of the templatewas noted with unmodified control templates. However, 15 nucleotideproducts, indicating blocking of DNA synthesis after incorporationof a nucleotide opposite the adduct and translesional synthesisproducts were formed in all cases in different amounts, dependingon the adduct structure. When a 14-mer primer together withhigh dNTP concentrations was used to examine nucleotide incorporationdirectly across from the four different purine adducts we foundthat the deoxyadenosine adducts (dA–AAI and dA–AAII)allowed incorporation of dAMP and dTMP equally well, whereasthe deoxyguanosine adducts (dG–AAI and dG–AAII)allowed preferential incorporation of dCMP. Molecular dynamicsimulations showed that the aristolactam moiety of all adductsexhibit a strong stacking, with the adenine residue at the 3'end of the 14-mer primer. These studies demonstrate that allAA purine adducts provide severe blocks to DNA replication andthat the guanine adducts may not be very efficient mutageniclesions. In contrast, the translesional bypass past adenineadducts of the aristolochic acids suggests a mutagenic potentialresulting from dAMP incorporation by polymerase. AT  相似文献   
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3-Nitrobenzanthrone (3-NBA) is a suspected human carcinogen found in diesel exhaust and ambient air pollution. The main metabolite of 3-NBA, 3-aminobenzanthrone (3-ABA), was recently detected in the urine of salt mining workers occupationally exposed to diesel emissions. Determining the capability of humans to metabolize 3-ABA and understanding which human enzymes are involved in its activation are important in the assessment of individual susceptibility. We compared the ability of eight human hepatic microsomal samples to catalyze DNA adduct formation by 3-ABA. Using the (32)P-postlabeling method, we found that all hepatic microsomes were competent to activate 3-ABA. DNA adduct patterns with multiple adducts, qualitatively similar to those formed in vivo in rats treated with 3-ABA, were observed. These patterns were also similar to those formed by the nitroaromatic counterpart 3-NBA and which derive from reductive metabolites of 3-NBA bound to purine bases in DNA. The role of specific cytochrome P450s (P450s) in the human hepatic microsomal samples in 3-ABA activation was investigated by correlating the P450-linked catalytic activities in each microsomal sample with the level of DNA adducts formed by the same microsomes. On the basis of this analysis, most of the hepatic microsomal activation of 3-ABA was attributable to P450 1A1 and 1A2 enzyme activity. Inhibition of DNA adduct formation in human liver microsomes by alpha-naphthoflavone and furafylline, inhibitors of P450 1A1 and 1A2, and P450 1A2 alone, respectively, supported this finding. Using recombinant human P450 1A1 and 1A2 expressed in Chinese hamster V79 cells and microsomes of baculovirus-transfected insect cells (Supersomes), we confirmed the participation of these enzymes in the formation of 3-ABA-derived DNA adducts. Moreover, essentially the same DNA adduct pattern found in microsomes was detected in metabolically competent human lymphoblastoid MCL-5 cells expressing P450 1A1 and 1A2. Using rat hepatic microsomes, we showed that both human and rat microsomes lead to the same 3-ABA-derived DNA adducts. Pretreatment of rats with beta-naphthoflavone or Sudan I, inducers of P450 1A1 and 1A2, and P450 1A1 alone, respectively, significantly stimulated the levels of 3-ABA-derived DNA adducts formed by rat liver microsomes. Utilizing purified rat recombinant P450 1A1, the participation of this enzyme in DNA adduct formation by 3-ABA was corroborated. In summary, our results strongly suggest a genotoxic potential of 3-ABA for humans. Moreover, 3-ABA is not only a suitable biomarker of exposure to 3-NBA but may also directly contribute to the high genotoxic potential of 3-NBA.  相似文献   
10.
3-nitrobenzanthrone (3-NBA) is a potent mutagen and suspected human carcinogen identified in diesel exhaust and ambient air pollution. 3-aminobenzanthrone (3-ABA), 3-acetylaminobenzanthrone (3-Ac-ABA) and N-acetyl-N-hydroxy-3-aminobenzanthrone (N-Ac-N-OH-ABA) have been identified as 3-NBA metabolites. Recently we found that 3-NBA and its metabolites (3-ABA, 3-Ac-ABA and N-Ac-N-OH-ABA) form the same DNA adducts in vivo in rats. In order to investigate whether human cytochrome P450 (CYP) enzymes (i.e., CYP1A2), human N,O-acetyltransferases (NATs) and sulfotransferases (SULTs) contribute to the metabolic activation of 3-NBA and its metabolites, we developed a panel of Chinese hamster V79MZ-h1A2 derived cell lines expressing human CYP1A2 in conjunction with human NAT1, NAT2, SULT1A1 or SULT1A2, respectively. Cells were treated with 0.01, 0.1 or 1 microM 3-NBA, or its metabolites (3-ABA, 3-Ac-ABA and N-Ac-N-OH-ABA). Using both enrichment versions of the (32)P-postlabeling assay, nuclease P1 digestion and butanol extraction, essentially 4 major and 2 minor DNA adducts were detected in the appropriate cell lines with all 4 compounds. The major ones were identical to those detected in rat tissue; the adducts lack an N-acetyl group. Human CYP1A2 was required for the metabolic activation of 3-ABA and 3-Ac-ABA (probably via N-oxidation) and enhanced the activity of 3-NBA (probably via nitroreduction). The lack of acetylated adducts suggests N-deacetylation of 3-Ac-ABA and N-Ac-N-OH-ABA. Thus, N-hydroxy-3-aminobenzanthrone (N-OH-ABA) appears to be a common intermediate for the formation of the electrophilic arylnitrenium ions capable of reacting with DNA. Human NAT1 and NAT2 as well as human SULT1A1 and SULT1A2 strongly contributed to the high genotoxicity of 3-NBA and its metabolites. Moreover, N,O-acetyltransfer reactions catalyzed by human NATs leading to the corresponding N-acetoxyester may be important in the bioactivation of N-Ac-N-OH-ABA. As human exposure to 3-NBA is likely to occur primarily via the respiratory tract, expression of CYPs, NATs and SULTs in respiratory tissues may contribute significantly and specifically to the metabolic activation of 3-NBA and its metabolites. Consequently, polymorphisms in these genes could be important determinants of lung cancer risk from 3-NBA.  相似文献   
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