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31.

Purpose

Interleukin-6 (IL-6) production and signalling are increased in the inflamed mucosa in inflammatory bowel diseases (IBD). As published serum levels of IL-6 and its soluble receptors sIL-6R and sgp130 in IBD are from small cohorts and partly contradictory, we systematically evaluated IL-6, sIL-6R and sgp130 levels as markers of disease activity in Crohn’s disease (CD) and ulcerative colitis (UC).

Methods

Consecutive adult outpatients with confirmed CD or UC were included, and their disease activity and medication were monitored. Serum from 212 CD patients (815 measurements) and 166 UC patients (514 measurements) was analysed, and 100 age-matched healthy blood donors were used as controls.

Results

IL-6 serum levels were significantly elevated in active versus inactive CD and UC, also compared with healthy controls. However, only a fraction of IBD patients showed increased serum IL-6. IL-6 levels ranged up to 32.7 ng/mL in active CD (>?5000-fold higher than in controls), but also up to 6.9 ng/mL in inactive CD. Increases in active UC (up to 195 pg/mL) and inactive UC (up to 27 pg/mL) were less pronounced. Associations between IL-6 serum levels and C-reactive protein concentrations as well as leukocyte and thrombocyte counts were observed. Median sIL-6R and sgp130 levels were only increased by up to 15%, which was considered of no diagnostic significance.

Conclusions

Only a minority of IBD patients shows elevated IL-6 serum levels. However, in these patients, IL-6 is strongly associated with disease activity. Its soluble receptors sIL-6R and sgp130 do not appear useful as biomarkers in IBD.
  相似文献   
32.

Objective

This study aimed to determine the inter-rater and intrarater reliability, agreement, and minimal detectable change (MDC) of the neck muscle strength test using a handheld dynamometer in healthy women and women with headaches.

Methods

Neck muscle strength in maximal voluntary contraction was measured using the Lafayette Manual Muscle Testing attached to a nonelastic belt in 25 women with migraines and in 25 healthy women. Three repetitions of flexion, extension, and lateral flexion were performed. The tests were performed by 2 examiners on the same day, with a 10-minute interval, and by 1 examiner, with a 1-week interval. The reliability was verified by the intraclass correlation coefficient, the agreement determined by standard error measurement, and the MDC calculated.

Results

The protocol exhibited moderate to excellent intrarater and inter-rater reliabilities in both groups (intraclass correlation coefficientrange, 0.53-0.90). The standard error measurement ranged from 0.43 to 1.81 and the MDC from 1.49 up to 4.61.

Conclusion

Quantification of neck muscle strength using the handheld dynamometer with an attached nonelastic belt exhibited moderate to excellent intra- and inter-rater reliability in women with and without migraines. Moreover, the standard error measurement and MDC were proven to be useful in the interpretation of data and in guiding clinical decisions.  相似文献   
33.
The association of aminopyridine-based acrylic acid and its salt was studied by NMR titration experiments. The AA (acceptor, acceptor) hydrogen-bonding pattern present in the salt forms a complex readily with a DD (donor, donor) hydrogen-bonding pattern of the substituted ureas even in polar and competitive environment. The double carbon–carbon bond in the acrylic acid derivative is subjected to photoisomerization. This is dependent on the association with substituted urea derivatives. The substituent in ureas influences the trans/cis isomerization kinetics and position of the photostationary state. Two mechanisms that influence the photoisomerization were proposed. To the best of our knowledge, the trans/cis photoisomerization influenced by the substituent in such a hydrogen-bonding pattern has not observed previously. It was shown that interaction with urea derivatives causes lowering of the trans-to-cis photoreaction rates.

The association of aminopyridine-based acrylic acid and its salt was studied by NMR titration experiments.  相似文献   
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Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) seems to employ two routes of entrance to the host cell; via membrane fusion (with the cells expressing both angiotensin converting enzyme 2 (ACE2) and transmembrane peptidase/serine subfamily member 2/4 (TMPRSS2/4)) or via receptor-mediated endocytosis (to the target cells expressing only ACE2). The second mode is associated with cysteine cathepsins (probably cathepsin L) involvement in the virus spike protein (S protein) proteolytic activation. Also furin might activate the virus S protein enabling it to enter cells. Gastrointestinal tract (GIT) involvement in SARS-CoV-2 infection is evident in a subset of coronavirus disease 2019 (COVID-19) patients exhibiting GIT symptoms, such as diarrhea, and presenting viral-shedding in feces. Considering the abundance and co-localization of ACE2 and TMPRSS2 in the lower GIT (especially brush-border enterocytes), these two receptors seem to be mainly involved in SARS-CoV-2 invasion of the digestive tract. Additionally, in vitro studies have demonstrated the virions capability of infection and replication in the human epithelial cells lining GIT. However, also furin and cysteine cathepsins (cathepsin L) might participate in the activation of SARS-CoV-2 spike protein contributing to the virus invasiveness within GIT. Moreover, cathepsin L (due to its involvement in extracellular matrix components degradation and remodeling, the processes enhanced during SARS-CoV-2-induced inflammation) might be responsible for the dysregulation of absorption/ digestion functions of GIT, thus adding to the observed in some COVID-19 patients symptoms such as diarrhea.  相似文献   
37.
Lactoferrin (Lf) was shown to exhibit its antiviral activity at an early phase of viral infection and a mechanism whereby the protein interacts with host cell surface molecules has been suggested. In this study, human Lf (HLf) and seven HLf‐derived synthetic peptides (HLP) corresponding to the N‐terminal domain of the native protein (1–47 amino acids sequence) were assayed for their capacity to prevent hepatitis B virus (HBV) infection and replication using the HepaRG and HepG2.2.2.15 cell lines. Of the series tested, four peptides showed 40–75% inhibition of HBV infection in HepaRG cells, HLP1–23, containing the GRRRR cationic cluster, being the most potent. Interestingly, this cluster is one of the two glycosaminoglycan binding sites of the native HLf involved in its antiviral activity; however, the mechanism of the HLP1–23 action was different from that of the full‐length protein, the peptide inhibiting HBV infection when pre‐incubated with the virus, while no effect was observed on the target cells. It is suggested that the cationic cluster is sufficient for the peptide to interact stably with negatively charged residues on the virion envelope, while the absence of the second glycosaminoglycan binding site prevents its efficient attachment to the cells. In conclusion, this peptide may constitute a non‐toxic approach for potential clinical applications in inhibiting HBV entry by neutralizing the viral particles. J. Med. Virol. 85:780–788, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
38.
BackgroundCytomegalovirus (CMV) reactivation remains one of the most frequent complications after allogeneic hematopoietic stem cell transplantation (HSCT).MethodsAn analysis of the pre-transplant risk factors of CMV reactivation was performed in 98 patients aged 0.5–22 years (median 10.5) undergoing allogeneic HSCT. CMV reactivation was tested by assessing viral load using PCR method. Following factors were analyzed: type of conditioning, graft source, donor type, use of T-depletion and CMV-serostatus of the donor and recipient. Each factor was assigned from 0 to 2 points. Based on total score for each patient, CMV reactivation risk scale was developed, and two groups with low (LR) and high (HR) risk were determined.ResultsCMV reactivation was seen in 25 patients (24.5%). The significant risk factors for CMV reactivation were: CMV-positive recipient (p<0.001), unrelated donor (p<0.002), use of ATG (p<0.002) and PBSC (p<0,01). In the HR group the incidence of reactivation CMV was significantly higher than in LR group (47.8% vs. 5.4%, p<0.001).ConclusionsCMV seropositivity of the recipient was an independent predictor factor of CMV reactivation. The use of risk point scale of CMV reactivation allows for identification of patients with the higher risk of CMV reactivation.  相似文献   
39.
European Journal of Clinical Microbiology & Infectious Diseases - In order to improve the diagnosis of giardiasis, fecal samples (high/medium/low concentration of cysts) were processed by the...  相似文献   
40.
Chelicerata, the second largest subphylum of Arthropoda, includes invertebrates with a wide range of body size. Pseudoscorpions are among small or miniature chelicerates which exhibit several morphological, anatomical, and developmental features related to miniaturization, e.g., replacement of book lungs by tracheae, unpaired gonads, and matrotrophic development of the embryos outside the female body, in the brood sac. In this paper, we show the ovary structure of two pseudoscorpion species, Cheiridium museorum and Apocheiridium ferum (Cheiridiidae). Both cheiridiids are one of the smallest pseudoscorpions. The results of our observations conducted in light, transmission electron, and confocal microscopy demonstrate that the ovary of C. museorum and A. ferum, displays a significant structural difference that is unusual for chelicerates. The difference concerns the spatially restricted position of the germarium. We show that such ovary architecture results in a significantly reduced number of growing oocytes and in consequence a reduced number of deposited eggs. A centrally located germarium implies also a modified pattern of ovary development during oocyte growth due to long distance migration of the germline and the accompanying somatic cells. Herein, we postulate that such an ovary structure is related to the pseudoscorpion's small body size and it is a step towards miniaturization in the smaller pseudoscorpions species.  相似文献   
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