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991.
Hypoxia induced by low O2 pressure is responsible for several physiological and behavioral alterations. Changes in physiological systems are frequent, including inflammation and psychobiological declines such as mood and cognition worsening, resulting in increased reaction time, difficulty solving problems, reduced memory and concentration. The paper discusses the possible relationship between glutamine supplementation and worsening cognition mediated by inflammation induced by high altitude hypoxia. The paper is a narrative literature review conducted to verify the effects of glutamine supplementation on psychobiological aspects. We searched MEDLINE/PubMed and Web of Science databases and gray literature by Google Scholar for English articles. Mechanistic pathways mediated by glutamine suggest potential positive effects of its supplementation on mood and cognition, mainly its potential effect on inflammation. However, clinical studies are scarce, making any conclusions impossible. Although glutamine plays an important role and seems to mitigate inflammation, clinical studies should test this hypothesis, which will contribute to a better mood and cognition state for several people who suffer from problems mediated by hypoxia.  相似文献   
992.
Using several complementary analytical methods, we demonstrated that the monoclonal antibody Trastuzumab (Tz), diluted in 0.9% sodium chloride can be stored in polyolefin infusion bags at 4 °C or room temperature up to 6 months with no evidence of chemical or physical instability. No aggregation of Tz was observed and its three dimensional structure remains unaltered. Thus, the practical use of diluted Tz can be safely extended to optimize the workload of centralized preparation units and to minimize costs.  相似文献   
993.
康福霞  曳凤黎 《医学争鸣》2000,21(12):1497-1497
0 引言 膀胱嗜铬细胞瘤是极少见的肿瘤 ,其典型的临床症状是排尿时或排尿后出现头痛、心慌、面色苍白、多汗和血压升高 ,B超、CT和尿 VMA检查可明确诊断 ,我科共收治膀胱嗜铬细胞瘤 5例 ,就其术前护理特点总结如下 .1 临床资料 本组 5 (男 3,女 2 )例 ,年龄 2 6~ 5 6岁 .5例测尿 VMA,4例显著高于正常 ,5例均通过膀胱镜检获得定位诊断 ,3例分别位于膀胱前、顶壁 ,2例分别位于膀胱颈及三角区 ,病体最大为 7cm× 8cm× 7cm,最小为直径 2 cm,2例经活检术前确诊 .病史 2 0 d~ 1a,5例均出现排尿时头晕、心慌及血压升高 ,3例伴有无痛性肉…  相似文献   
994.
Three withaphysalins, rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-2,24-dienolide(withaphysalin M) (1), rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-18-ethoxy-1-oxowitha-2,24-dienolide (withaphysalin F ethyl ether, withaphysalin O) (2), and rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-24-enolide (withaphysalin N) (3), were isolated from the leaves of Acnistus arborescens. The structures were deduced from 1D ((1)H NMR, (13)C NMR, DEPT-(13)C NMR) and 2D (COSY, HMQC, HMBC) NMR analysis and the relative stereochemical assignments based on 1D NOESY correlations and analysis of coupling constants. Compounds 1 and 2 displayed potent cytotoxic activity against a panel of human cancer cell lines.  相似文献   
995.

Ethnopharmacological relevance

The leaves of Hancornia speciosa Gomes are popularly used in Brazil to treat diabetes and hypertension. Cardiovascular diseases are the main cause of death worldwide and their incidences are increasing in Brazilian population. The present study aimed to investigate the hypotensive effect and the mechanism of action of Hancornia speciosa Gomes.

Methods

A fraction of the ethanolic extract of leaves from Hancornia speciosa (SFH) was obtained and standardized by its content on rutin, bornesitol and quinic acid. Systolic blood pressure (SBP) of normotensive mice was measured by tail pletismography. SFH was given orally and SBP was monitored for 5 h. Angiotensin-converting enzyme (ACE) inhibitor activity of SFH (1 mg/kg) or captopril (10 mg/kg) was measured by colorimetric methods. Serum nitrite levels were measured by spectrophotometry.

Results

SFH induced a dose-dependent hypotensive effect in normotensive mice. The serum activity of ACE and the level of angiotensin II were significantly reduced by SFH and by captopril. Administration of SFH induced a significant increase on plasmatic level of nitrites and the systemic inhibition of nitric oxide synthase by L-NAME (20 mg/kg) reduced the hypotensive effect of SFH.

Conclusions

The present work demonstrated that Hancornia speciosa has a potent hypotensive effect in normotensive mice. The inhibition of ACE leading to reduction on angiotensin II and increase on NO levels might account for the hypotensive effect. These results support the use of Hancornia speciosa by traditional medicine as antihypertensive.  相似文献   
996.

Ethnopharmacological relevance

Brassica oleracea L. var. acephala D.C. has been extensively used in Brazilian traditional medicine to treat gastric ulcer.

Aim of the study

This study was conducted to evaluate the in vivo genotoxic and/or antigenotoxic potential of a Brassica oleraceae hydroalcoholic extract obtained from the leaves, in different cells of mice.

Materials and methods

Analyses were performed using the comet assay, on leukocytes (collected 4 and 24 h after treatment), liver, brain, bone marrow and testicular cells (collected 24 h after treatment), and using the micronucleus test (MN) in bone marrow cells. Eight groups of albino Swiss mice were treated (N=6): control (C), positive control (doxorubicin 80 mg/kg (DXR)), and six experimental groups, which received 500, 1000 and 2000 mg/kg of Brassica oleraceae extract alone by gavage, while a further three groups received the same doses plus DXR (80 mg/kg). We calculated the damage scores, and their averages were compared by ANOVA followed by the Tukey test for multiple comparisons.

Results

The results demonstrated that none of the tested doses of Brassica oleraceae extract showed genotoxic effects by the comet assay, or clastogenic effects by the MN test. On the other hand, for all cells evaluated, the three tested doses of the Brassica extract promoted inhibition of DNA damage induced by DXR.

Conclusions

Under our experimental conditions, Brassica oleraceae leaf extract showed no genotoxic or clastogenic effects in different cells of mice. However, it did show a significant decrease in DNA damage induced by doxorubicin. It is suggested that the antigenotoxic properties of this extract may be of great pharmacological importance, and may be beneficial for cancer prevention.  相似文献   
997.
998.
T-cell mediated immune responses are critical for acquired immunity against infection by the intracellular protozoan parasite Trypanosoma cruzi. Despite its importance, it is currently unknown where protective T cells are primed and whether they need to re-circulate in order to exert their anti-parasitic effector functions. Here, we show that after subcutaneous challenge, CD11c(+)-dependent specific CD8(+) T-cell immune response to immunodominant parasite epitopes arises almost simultaneously in the draining lymph node (LN) and the spleen. However, until day 10 after infection, we observed a clear upregulation of activation markers only on the surface of CD11C(+)PDCA1(+) cells present in the LN and not in the spleen. Therefore, we hypothesized that CD8(+) T cells re-circulated rapidly from the LN to the spleen. We investigated this phenomenon by administering FTY720 to T. cruzi-infected mice to prevent egress of T cells from the LN by interfering specifically with signalling through sphingosine-1-phosphate receptor-1. In T. cruzi-infected mice receiving FTY720, CD8 T-cell immune responses were higher in the draining LN and significantly reduced in their spleen. Most importantly, FTY720 increased susceptibility to infection, as indicated by elevated parasitemia and accelerated mortality. Similarly, administration of FTY720 to mice genetically vaccinated with an immunodominant parasite antigen significantly reduced their protective immunity, as observed by the parasitemia and survival of vaccinated mice. We concluded that re-circulation of lymphocytes mediated by sphingosine-1-phosphate receptor-1 greatly contributes to acquired and vaccine-induced protective immunity against experimental infection with a human protozoan parasite.  相似文献   
999.
Ambient particles have been consistently associated with adverse health effects, yielding mainly high cardiorespiratory morbidity and mortality. Diesel engines represent a major source of particles in the urban scenario. We aimed to modify the composition of diesel particles, by means of different extraction procedures, to relate changes in chemical profile to corresponding indicators of respiratory toxicity. Male BALB/c mice were nasally instilled with saline, or with diesel particles, treated or not, and assigned to five groups: saline (SHAM), intact diesel particles (DEP), and diesel particles previously treated with methanol (METH), hexane (HEX), or nitric acid (NA). Elemental composition and organic compounds were analyzed. Twenty-four hours after nasal instillation, respiratory parameters were measured and lung tissue was collected for histological analysis. Static elastance was significantly increased in groups DEP and MET in relation to the other groups. HEX and NA were different from DEP but not significantly different from SHAM and METH groups. The difference between dynamic and static elastance was increased in DEP, METH, and NA treatments; HEX was not statistically different from SHAM. DEP and METH groups presented significantly increased upper airways resistance, while DEP, METH, and NA showed higher peripheral airways resistance values. All groups had a higher total resistance than SHAM. DEP, METH, and NA showed significant increased infiltration of polymorphonuclear cells. In conclusion, diesel particles treated with hexane (HEX) resulted in a respiratory-system profile very similar to that in SHAM group, indicating that hexane treatment attenuates pulmonary inflammation elicited by diesel particles.  相似文献   
1000.
We compared the results obtained by serotyping of PorB epitopes using an expanded panel of monoclonal antibodies (mAb) including mAb 7 and mAb 10, with results obtained by RFLP of rRNA genes (ribotyping). The purpose of this study was to assess the correlation between phenotypic- and genotypic- methods for typing N. meningitidis. The ribotypes obtained using ClaI or EcoRV endonucleases grouped the strains in seven and two different patterns, respectively. This additional characterization of PorB epitopes improved the correlation between these two methods of typing N. meningitidis.  相似文献   
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