全文获取类型
收费全文 | 177篇 |
免费 | 5篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 11篇 |
2014年 | 8篇 |
2013年 | 7篇 |
2012年 | 13篇 |
2011年 | 8篇 |
2010年 | 8篇 |
2009年 | 4篇 |
2008年 | 9篇 |
2007年 | 5篇 |
2006年 | 8篇 |
2005年 | 14篇 |
2004年 | 9篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 5篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有182条查询结果,搜索用时 15 毫秒
81.
Shagirova Zh. M. Kurbatova L. A. Shulenina L. V. Semyachkina A. N. Mikhailov V. F. Zasukhina G. D. 《Biophysics》2011,56(5):950-954
Codon 312 and 751 polymorphisms of XPD gene and codon 399 polymorphism of XRCC1 gene of peripheral blood lymphocytes in patients with Down syndrome (DS) (46 individuals) and Ehlers-Danlo syndrome (EDS)
(47 individuals) and in a group of healthy donors (control) (40 individuals) were studied. The frequency of XPD genotype (G312G) coding for the most effectively functioning form of XPD protein was lower in patients with DS (26%) than
in the group of healthy donors (42.5%) (p = 0.035), whereas no significant differences with the control were revealed for this codon in patients with EDS. No patients
with XPD genotype (C751C) (p = 0.036) were revealed in the group of EDS patients, while this genotype was found in 16% of the group of healthy donors
and in 17% of patients with DS. A trend of XRCC1 genotype frequency reduction (A399A) (p = 0.085) in EDS patients (3.9%) compared with the group of healthy donors (13.5%) and DS patients (13.3%) was obtained. These
data showed that polymorphisms of the excision repair genes under study were accompanied by an elevated individual radiosensitivity
in patients with DS. Genes investigated (their polymorphic variants) did not participate in the mechanisms for radiosensitive
phenotype formation in EDS patients. 相似文献
82.
Courtney M. Yuen Ekaterina V. Kurbatova Eleanor S. Click J. Sean Cavanaugh J. Peter Cegielski 《PloS one》2013,8(12)
Background
Development of resistance to antituberculosis drugs during treatment (i.e., acquired resistance) can lead to emergence of resistant strains and consequent poor clinical outcomes. However, it is unknown whether Mycobacterium tuberculosis complex species and lineage affects the likelihood of acquired resistance.Methods
We analyzed data from the U.S. National Tuberculosis Surveillance System and National Tuberculosis Genotyping Service for tuberculosis cases during 2004–2011 with assigned species and lineage and both initial and final drug susceptibility test results. We determined univariate associations between species and lineage of Mycobacterium tuberculosis complex bacteria and acquired resistance to isoniazid, rifamycins, fluoroquinolones, and second-line injectables. We used Poisson regression with backward elimination to generate multivariable models for acquired resistance to isoniazid and rifamycins.Results
M. bovis was independently associated with acquired resistance to isoniazid (adjusted prevalence ratio = 8.46, 95% CI 2.96–24.14) adjusting for HIV status, and with acquired resistance to rifamycins (adjusted prevalence ratio = 4.53, 95% CI 1.29–15.90) adjusting for homelessness, HIV status, initial resistance to isoniazid, site of disease, and administration of therapy. East Asian lineage was associated with acquired resistance to fluoroquinolones (prevalence ratio = 6.10, 95% CI 1.56–23.83).Conclusions
We found an association between mycobacterial species and lineage and acquired drug resistance using U.S. surveillance data. Prospective clinical studies are needed to determine the clinical significance of these findings, including whether rapid genotyping of isolates at the outset of treatment may benefit patient management. 相似文献83.
Max W. Adelman Ekaterina Kurbatova Yun F. Wang Michael K. Leonard Nancy White Deborah A. McFarland Henry M. Blumberg 《PloS one》2014,9(7)
Introduction
The Centers for Disease Control and Prevention has recommended using a nucleic acid amplification test (NAAT) for diagnosing pulmonary tuberculosis (TB) but there is a lack of data on NAAT cost-effectiveness.Methods
We conducted a prospective cohort study that included all patients with an AFB smear-positive respiratory specimen at Grady Memorial Hospital in Atlanta, GA, USA between January 2002 and June 2008. We determined the sensitivity, specificity, and positive and negative predictive value of a commercially available and FDA-approved NAAT (amplified MTD, Gen-Probe) compared to the gold standard of culture. A cost analysis was performed and included costs related to laboratory tests, hospital charges, anti-TB medications, and contact investigations. Average cost per patient was calculated under two conditions: (1) using a NAAT on all AFB smear-postive respiratory specimens and (2) not using a NAAT. One-way sensitivity analyses were conducted to determine sensitivity of cost difference to reasonable ranges of model inputs.Results
During a 6 1/2 year study period, there were 1,009 patients with an AFB smear-positive respiratory specimen at our public urban hospital. We found the NAAT to be highly sensitive (99.6%) and specific (99.1%) on AFB smear-positive specimens compared to culture. Overall, the positive predictive value (PPV) of an AFB smear-positive respiratory specimen for culture-confirmed TB was 27%. The PPV of an AFB smear-positive respiratory specimen for culture-confirmed TB was significantly higher for HIV-uninfected persons compared to those who were HIV-seropositive (152/271 [56%] vs. 85/445 [19%]; RR = 2.94, 95% CI 2.36–3.65, p<0.001). The cost savings of using the NAAT was $2,003 per AFB smear-positive case.Conclusions
Routine use of the NAAT on AFB smear-positive respiratory specimens was highly cost-saving in our setting at a U.S. urban public hospital with a high prevalence of TB and HIV because of the low PPV of an AFB smear for culture-confirmed TB. 相似文献84.
Background
Interferon-α in combination with ribavirin is the current gold standard for treatment of chronic hepatitis C. It is unknown if the development of autoimmune thyroid disease (TD) during treatment confers an improved chance of achieving sustained virologic response. The aim of this study is to assess the chance of achieving sustained virologic response (SVR) in patients who developed TD during treatment when compared with those who did not.Methods
We performed a tertiary hospital-based retrospective nested case-control analysis of 19 patients treated for hepatitis C who developed thyroid disease, and 76 controls (matched for age, weight, gender, cirrhosis and aminotransferase levels) who did not develop TD during treatment. Multivariate logistic-regression models were used to compare cases and controls.Results
The development of TD was associated with a high likelihood of achieving SVR (odds ratio, 6.0; 95% confidence interval, 1.5 to 24.6) for the pooled group containing all genotypes. The likelihood of achieving SVR was increased in individuals with genotype 1 HCV infection who developed TD (odds ratio, 5.2; 95% confidence interval, 1.2 to 22.3), and all genotype 3 patients who developed TD achieved SVR.Conclusions
Development of TD during treatment for hepatitis C infection is associated with a significantly increased chance of achieving SVR. The pathophysiogical mechanisms for this observation remain to be determined.Trial Registration
The Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRB12610000830099 相似文献85.
Background
Foreign-born individuals comprise >50% of tuberculosis (TB) cases in the U.S. Since anti-TB drug resistance is more common in most other countries, when evaluating a foreign-born individual for TB, one must consider the risk of drug resistance. Naturally, clinicians query The Global Project on Anti-tuberculosis Drug Resistance Surveillance (Global DRS) which provides population-based data on the prevalence of anti-TB drug resistance in 127 countries starting in 1994. However, foreign-born persons in the U.S. are a biased sample of the population of their countries of origin, and Global DRS data may not accurately predict their risk of drug resistance. Since implementing drug resistance surveillance in 1993, the U.S. National TB Surveillance System (NTSS) has accumulated systematic data on over 130,000 foreign-born TB cases from more than 200 countries and territories. Our objective was to determine whether the prevalence of drug resistance among foreign-born TB cases correlates better with data from the Global DRS or with data on foreign-born TB cases in the NTSS.Methods and Findings
We compared the prevalence of resistance to isoniazid and rifampin among foreign-born TB cases in the U.S., 2007–2009, with US NTSS data from 1993 to 2006 and with Global DRS data from 1994–2007 visually with scatterplots and statistically with correlation and linear regression analyses. Among foreign-born TB cases in the U.S., 2007–2009, the prevalence of isoniazid resistance and multidrug resistance (MDR, i.e. resistance to isoniazid and rifampin), correlated much better with 1993–2006 US surveillance data (isoniazid: r = 0.95, P<.001, MDR: r = 0.75, P<.001) than with Global DRS data, 1994–2007 (isoniazid: r = 0.55, P = .001; MDR: r = 0.50, P<.001).Conclusion
Since 1993, the US NTSS has accumulated sufficient data on foreign-born TB cases to estimate the risk of drug resistance among such individuals better than data from the Global DRS. 相似文献86.
O. L. Kurbatova E. Yu. Pobedonostseva F. R. Gurgenova K. B. Bulaeva 《Russian Journal of Genetics》2012,48(10):1048-1054
Using the 2002 All-Russian population census data, the parameters of differential fertility as a component of natural selection (Crow??s indices) have been calculated for women of seven age cohorts of the seven most numerous ethnic groups of the Republic of Dagestan. It has been shown that in the population of Dagestan in the second half of the 20th century the intensities of two types of selection tended to decrease, viz., intragroup selection relaxed in each ethnic group due to considerable reduction of interfamily variance in fertility and intergroup selection relaxed due to reduction of interethnic differences in fertility. A reduction of the average number of offspring (k) was observed in all ethnic groups, suggesting the spread of birth regulation practices (abortion and contraception). Nevertheless, all Muslim groups (aboriginal Dagestan ethnic groups and Azerbaijanis) are still characterized by an extended pattern of reproduction (2.7 < k < 3.3); in Russians k = 2.1. Interethnic differentials in natural reproduction rates, along with migration processes, account for the dynamics of the ethnic composition and gene-pool structure of the population of the Republic of Dagestan. 相似文献
87.
WalterDuartedeAraujo Filho Fábio Kurt Schneider Rigoberto EM Morales 《Biomedical engineering online》2012,11(1):1-14
Background
In recent years magnesium alloys have been intensively investigated as potential resorbable materials with appropriate mechanical and corrosion properties. Particularly in orthopedic research magnesium is interesting because of its mechanical properties close to those of natural bone, the prevention of both stress shielding and removal of the implant after surgery.Methods
ZEK100 plates were examined in this in vitro study with Hank's Balanced Salt Solution under physiological conditions with a constant laminar flow rate. After 14, 28 and 42 days of immersion the ZEK100 plates were mechanically tested via four point bending test. The surfaces of the immersed specimens were characterized by SEM, EDX and XRD.Results
The four point bending test displayed an increased bending strength after 6 weeks immersion compared to the 2 week group and 4 week group. The characterization of the surface revealed the presence of high amounts of O, P and Ca on the surface and small Mg content. This indicates the precipitation of calcium phosphates with low solubility on the surface of the ZEK100 plates.Conclusions
The results of the present in vitro study indicate that ZEK100 is a potential candidate for degradable orthopedic implants. Further investigations are needed to examine the degradation behavior. 相似文献88.
YK Onno Teng Gillian Wheater Vanessa E Hogan Philip Stocks EW Nivine Levarht Tom WJ Huizinga Rene EM Toes Jacob M van Laar 《Arthritis research & therapy》2012,14(2):R57
Introduction
B-cell depletion has become a common treatment strategy in anti-TNF-refractory rheumatoid arthritis (RA). Although the exact mechanism of how B-cell depletion leads to clinical amelioration in RA remains to be elucidated, repetitive treatment with B-cell-depleting agents leading to long-term B-cell depletion has been reported to be beneficial. The latter has led to the hypothesis that the beneficial effects of B-cell depletion might act through their influence on pathogenic autoreactive plasma cells.Methods
In this study, we investigated the effects of a fixed retreatment regimen with anti-CD20 mAbs on the humoral (auto)immune system in a cohort of therapy-refractory RA patients.Results
Fixed retreatment led to long-term B-cell depletion in peripheral blood, bone marrow and, to a lesser extent, synovium. Also, pathologic autoantibody secretion (that is, anticitrullinated peptide antibodies (ACPAs)) was more profoundly affected by long-term depletion than by physiological protective antibody secretion (that is, against measles, mumps and rubella). This was further illustrated by a significantly shorter estimated life span of ACPA-IgG secretion compared to total IgG secretion as well as protective antibody secretion.Conclusion
By studying plasma cell function during an extensive 2-year period of B-cell depletion, autoantibody secretion was significantly shorter-lived than physiologically protective antibody secretion. This suggests that the longevity of autoreactive plasma cells is different from protective long-lived plasma cells and might indicate a therapeutic window for therapies that target plasma cells. 相似文献89.
90.
L V Miriasova I A Basnak'ian N B Egorova E A Kurbatova L N Reshilov A Iu Krylova O V Efimtseva N L Shagam V F Salov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(7):43-46
In the technology of the cultivation of K. pneumoniae vaccine strain 204 with a view to obtaining biomass for the production of antigenic preparations the traditionally used culture medium with full nutritional value has been replaced by the alternative variant of synthetic medium. The specific physiological and morphological features of this strain grown in synthetic culture medium have been studied and described. Irrespective of the composition of the culture media used for cultivation, the antigenic preparations have been shown to have no difference in their chemical composition, immunogenic and toxic properties. 相似文献