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1.
In a recent study (Oldoni & García, 2007), some field strains of infectious laryngotracheitis viruses (ILTV) were characterized as genotypically different (group VI) from ILT vaccine strains. The objective of this study was to evaluate the protection elicited by one chicken embryo origin (CEO) and one tissue culture origin (TCO) vaccine against a field isolate from group VI after direct and indirect exposure to ILTV live attenuated vaccines. In phase 1 of the experiment, non-vaccinated chickens were placed into contact with the eye drop vaccinates for a period of four weeks after vaccination. Transmission of the vaccine virus to these in-contact birds was demonstrated by real time PCR and antibody production, although the in-contact birds did not become protected against disease when subsequently challenged in phase 2 of the experiment. This emphasized the importance of uniform vaccination to obtain adequate protection, both to avoid the occurrence of susceptible chickens, and to minimize the potential for reversion to virulence of live-attenuated vaccines. In phase 2, protection against challenge with a group VI field virus was assessed four weeks after vaccination by scoring clinical signs and mortality, and quantifying weight gain. Sentinel birds were added to the groups one day after challenge to assess shedding of challenge virus, using real time PCR and virus isolation, during the period 2 to 12 days post challenge. The results showed that the CEO and TCO eye drop-vaccinated chickens were protected against challenge with the group VI virus, even though it was genetically different from the vaccine strains, and that challenge virus was not transmitted from these protected birds to the sentinels.  相似文献   
2.
The aim of this study is to report our 3years experience with the screening of congenital disorders of glycosylation. A common isoelectric focusing method with immunofixation was used for analysis of serum transferrin and alpha1-antitrypsin, apart from several other procedures. A group of about 1000 individuals, both healthy controls and patients, mostly with signs of a metabolic disease were examined. Here we present an overview of (1) hypoglycosylation findings, (2) distribution of protein variants, (3) misguiding rare Tf variants found in our set, and (4) association of some phenotypes with various diseases.  相似文献   
3.
The BAB/14 (BALB/c.C57BL/Ka-Ig-1b/Hz) congenic mouse strain was found to respond to (4-hydroxy-3-nitrophenyl)acetyl (NP)-chicken globulin immunization with nonheteroclitic anti-NP antibodies as does the BALB/c inbred partner strain. This is in contrast to the heteroclitic anti-NP response of the C57BL/Ka allotype donor strain and indicates that the allotype linked VH-NP gene was inherited with the VH-DEX gene from BALB/c rather than with the allotype genes from C57BL/Ka. This verifies the interpretation of BAB/14 as an immunoglobulin gene recombinant. Two recombinants between VH-DEX and Ig-1 allotype genes have been found among 554 chromosomes tested yielding a recombination frequency of 0.4%. Analysis of the BAB/14 recombinant showed that this crossover occurred between VH genes implying that VH genes and CH genes are not organized in separate clusters separated by a large spacer region but are contiguous. Analysis of the recombination frequencies indicates that the total number of VH genes must be at least 50.  相似文献   
4.
Antibodies to tumor necrosis factor (TNF)-α have been recently proposed as effective treatment for patients with Crohn's disease. Here, we analyze the functional role of TNF-α in a mouse model of chronic intestinal inflammation induced by the hapten reagent 2,4,6,-trinitrobenzene sulfonic acid (TNBS) that mimics some characteristics of Crohn's disease in humans. Macrophage-enriched lamina propria (LP) mononuclear cells from mice with TNBS-induced colitis produced 10–30-fold higher levels of TNF-α mRNA and protein than cells from control mice. When mice with chronic colitis were treated by intraperitoneal injection of antibodies to TNF-α, an improvement of both the clinical and histopathologic signs of disease was found. Isolated macrophage-enriched LP cells from anti-TNF-α-treated mice produced strikingly less pro-inflammatory cytokines such as interleukin (IL)-1 and IL-6 in cell culture. The predominant role of TNF-α in the mouse TNBS-induced colitis model was further underlined by the finding that striking colonic inflammation and lethal pancolitis was induced in TNF-α-transgenic mice upon TNBS treatment. Conversely, no significant TNBS-induced colitis could be induced in mice in which the TNF-α gene had been inactivated by homologous recombination. Complementation of TNF-α function in TNF?/? mice by the expression of a mouse TNF-α transgene was sufficient to reverse this effect. Taken together, the data provide direct evidence for a predominant role of TNF-α in a mouse model of chronic intestinal inflammation and encourage further clinical trials with antibodies to TNF-α for the treatment of patients with Crohn's disease.  相似文献   
5.
Clinical trials have demonstrated that buspirone (BuSpar) is effective in the treatment of anxiety with efficacy and dosage comparable to diazepam or chlorazepate. Buspirone has a unique structure and a pharmacologic profile which distinguishes it from the benzodiazepines. Because it lacks the anticonvulsant, sedative, and muscle-relaxant properties associated with other anxiolytics, buspirone has been termed "anxioselective." Animal studies suggest that it lacks potential for abuse, and this finding is supported by clinical investigations. Further preclinical work supports the contention that buspirone lacks liability to produce physical dependence or to significantly interact with central nervous system depressants such as ethanol. Moreover, biochemical investigations have not identified any direct interaction of buspirone with the benzodiazepine-gamma-aminobutyric acid-chloride ionophore complex. Pharmacologic studies on the molecular level indicate that buspirone interacts with dopamine and serotonin receptors. Recent behavioral, electrophysiological, and biochemical studies have clearly demonstrated that early hypotheses that buspirone might be considered a neuroleptic are no longer tenable. Recent evidence indicates that other neurotransmitter systems (serotonin, norepinephrine, acetylcholine) mediate buspirone's effects. It is hoped that future studies can define the mechanism by which buspirone alleviates the clinical manifestations of anxiety.  相似文献   
6.
7.
In this study, the development and validation of a real-time (ReTi) PCR assay is described using a Taqman labeled probe for the detection and quantitation of infectious larygotracheitis virus (ILTV) in chickens. The ReTi ILTV assay was highly specific with a quantitation limit of 100 viral template copies per amplification reaction. In experimentally infected, birds during early acute stages of infection, an average of 6.67 log(10) viral template copies/amplification reaction were detected, while at chronic late stages of infection an average of 2.86-3.27 log(10) viral template copies/amplification reaction were detected. A total of 246 tracheal swab samples collected from natural outbreaks of the disease were tested by virus isolation and the ReTi ILTV assay. Both assays agreed in 37% of the samples tested and the ReTi ILTV assay detected approximately 3.7 times more positives samples than virus isolation. A minimum of 5 log(10) viral template copies/amplification reaction were required from a tracheal swab to render a virus isolation positive result. In conclusion, the ReTi ILTV assay was highly specific, sensitive, reproducible, and capable of reliably quantifying viral nucleic acid directly from clinical samples.  相似文献   
8.

Objective

Prior reviews evaluating the role of antidepressants in cancer-related depression have drawn conflicting conclusions. These reviews have also not explored differences in efficacy and tolerability between antidepressants. We conducted a meta-analysis to address these limitations.

Method

We searched Medline (1948–2013), the Cochrane Library (1800–2013), the Cumulative Index to Nursing and Allied Health Literature (1986–2013), ClinicalTrials.gov (2013) and meeting abstracts. We included randomized trials comparing antidepressants to placebo or no treatment for cancer-related depression. We used random effects to calculate standardized mean differences (SMD).

Results

Of 5178 potentially eligible citations, 9 trials (1169 subjects) met inclusion criteria. Trials of mianserin found a robust reduction in depression scores at ≥ 4 weeks of treatment (SMD: 0.60, 95% confidence interval (CI): 0.24–0.95). Similar, but less robust, results were observed with paroxetine (SMD: 0.22, 95% CI: 0.01–0.42) and fluoxetine (SMD 0.34, 95% CI: 0.02–0.66). Conversely, there was no advantage with amitriptyline or desipramine. Compared to placebo, the odds of dropping out due to side effect were higher with fluoxetine and paroxetine and lower with mianserin. Methodological quality was moderate.

Conclusions

Paroxetine, fluoxetine and mianserin improve cancer-related depression but may vary in efficacy and tolerability. High-quality, randomized trials of newer antidepressant agents are needed to identify optimal treatments for managing cancer-related depression.  相似文献   
9.
10.
Background: The diagnosis of SARS-CoV-2 is almost exclusively performed by PCR or antigen detection. The detection of specific antibodies has not yet been considered in official diagnostic guidelines as major laboratory evidence for a case definition. The aim the present study is to analyze antibody responses in outpatient and inpatient cohorts of COVID-19 patients in the Czech Republic over a 12-month period, and assess the potential of antibodies as a diagnostic tool. Methods: A total of 644 patients was enrolled in the prospective study. IgA, IgM and IgG antibody levels, as well as virus neutralization titers, were analyzed over a 12-month period. Results: Our study showed low antibody positivity levels at the admission. However, at 2 weeks after infection, 98.75% and 95.00% of hospitalized patients were IgA and IgG positive, respectively. Even in the outpatient cohort characterized by milder disease courses, the IgG antibody response was still sustained at 9 and 12 months. The data show a high correlation between the IgG levels and virus neutralization titers (VNTs). Samples from later time-points showed positive antibody responses after vaccination in both cohorts characterized by high IgG levels and VNT over 1:640. The samples from unvaccinated persons indicated a relatively high level of reinfection at 6.87%. Conclusions: Our results show that the detection of antibodies against the SARS-CoV-2 shows an increasing sensitivity from week 2 after infection and remains highly positive over the 12-month period. The levels of IgG antibodies correlate significantly with the VNTs. This suggests that the serological data may be a valuable tool in the diagnosis of SARS-CoV-2 infection.  相似文献   
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