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21.
Forensic Science, Medicine and Pathology - Forensic entomology is a discipline in which insect evidence is used to determine the minimum postmortem interval (PMImin). The insect evidence may also...  相似文献   
22.
It has been previously shown that acetylcholine (ACh) may affect pro-inflammatory and anti-inflammatory cytokines. The role of the cholinergic system in radiation-induced inflammatory responses and tissue damage remains unclear. Therefore, the present study was designed to determine the radio-protective properties of the cholinergic system in the ileum and the liver of rats. Rats were exposed to 8-Gy single-fraction whole-abdominal irradiation and were then decapitated at either 36 h or 10 d post-irradiation. The rats were treated either with intraperitoneal physiological saline (1 ml/kg), physostigmine (80 µg/kg) or atropine (50 μg/kg) twice daily for 36 h or 10 d. Cardiac blood samples and liver and ileal tissues were obtained in which TNF-α, IL-1β and IL-10 levels were assayed using ELISA. In the liver and ileal homogenates, caspase-3 immunoblots were performed and myeloperoxidase (MPO) activity was analyzed. Plasma levels of IL-1β and TNF-α increased significantly following radiation (P < 0.01 and P < 0.001, respectively) as compared with non-irradiated controls, and physostigmine treatment prevented the increase in the pro-inflammatory cytokines (P < 0.01 and P < 0.001, respectively). Plasma IL-10 levels were not found to be significantly changed following radiation, whereas physostigmine augmented IL-10 levels during the late phase (P < 0.01). In the liver and ileum homogenates, IL-1β and TNF-α levels were also elevated following radiation, and this effect was inhibited by physostigmine treatment but not by atropine. Similarly, physostigmine also reversed the changes in MPO activity and in the caspase-3 levels in the liver and ileum. Histological examination revealed related changes. Physostigmine experiments suggested that ACh has a radio-protective effect not involving the muscarinic receptors.  相似文献   
23.

PURPOSE

The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al2O3 and two Y-TZP core materials.

MATERIALS AND METHODS

Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data.

RESULTS

The characteristic strengths of Ce-TZP/Al2O3 specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05).

CONCLUSION

It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.  相似文献   
24.
Hybrid polymers of peptides resembling (partially) folded protein structures are promising materials in biomedicine, especially in view of folding-interactions between different segments. In this study polymers bearing repetitive peptidic folding elements, composed of N-terminus functionalized bis-ω-ene-functional oligo-l-lysine(carboxybenzyl(Z))s (Lysn) with repeating units (n) of 3, 6, 12, 24 and 30 were successfully synthesized to study their secondary structure introduced by conformational interactions between their chains. The pre-polymers of ADMET, narrowly dispersed Lysns, were obtained by ring opening polymerization (ROP) of N-carboxyanhydride (NCA) initiated with 11-amino-undecene, following N-terminus functionalization with 10-undecenoyl chloride. The resulting Lysns were subsequently polymerized via ADMET polymerization by using Grubbs’ first generation (G1) catalyst in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) generating the ADMET polymers (A-[Lysn]m) (m = 2–12) with molecular weights ranging from 3 to 28 kDa, displaying polydispersity (Đ) values in the range of 1.5–3.2. After chemical analyses of Lysns and A-[Lysn]ms by 1H-NMR, GPC and MALDI-ToF MS, secondary structural investigations were probed by CD spectroscopy and IR spectroscopy in 2,2,2-trifluoroethanol (TFE). In order to study A-[Lysn]ms with defined molecular weights and low polydispersity values (Đ = 1.03–1.48), the ADMET polymers A-[Lysn=3]m=3 and A-[Lysn=24]m=4 were fractionated by preparative GPC, and subsequently analysed by 1H-NMR, analytical GPC, MALDI-ToF MS and CD spectroscopy. We can demonstrate the influence of chain length of the generated polymers on the formation of secondary structures by comparing Lysns with varying n values to the ADMET-polymers with the help of spectroscopic techniques such as CD and FTIR-spectroscopy in a helicogenic solvent.

We demonstrate the influence of chain length of segmented polymers bearing dynamic folding elements onto the formation of secondary structures with the help of spectroscopic techniques such as CD and FTIR-spectroscopy in a helicogenic solvent.  相似文献   
25.
Background: To our knowledge, there is no study comparing Ponto Plus® (Oticon Medical AB, Askim, Sweden) and Baha® 5 (Cochlear Bone Anchored Solutions AG, Mölnlycke, Sweden) available in the literature.

Aims/objectives: The primary aim was to compare the performance of the Baha 5 with the Ponto Plus device in terms of speech understanding in quiet and in noise. In addition, to determine statistically whether or not the difference between the abutment systems created any variation in terms of skin reaction.

Materials and methods: Twenty bone-anchored hearing instrument users, ten in each group, were evaluated for speech understanding in quiet and several signal-to-noise ratios using the Turkish Matrix Test in a two-speaker setup. The Holger classifications were also reviewed to determine adverse skin reactions.

Results: It was revealed that the hearing results of both devices were similar and, when the skin reactions were compared, there was no statistically significant difference between the two-implant systems.

Conclusions and significance: Because of the similar results of the groups, it can be interpreted as the key different device features such as the size, weight, colour alternatives, and the ease of use of the devices might be important in terms of device preference.  相似文献   
26.
Silver linden, Tilia argentea Desf. ex DC (Tiliaceae) leaves are used in the treatment of common cold and bronchitis. In order to evaluate this information, antinociceptive and anti-inflammatory activities of the two main flavonoid glycosides: kaempferol-3,7-O-alpha-dirhamnoside and quercetin-3,7-O-alpha-dirhamnoside isolated from the leaves, were investigated. For the antinociceptive activity, p-benzoquinone-induced writhing test and for the anti-inflammatory activity, carrageenan-induced hind paw edema model in mice were used. Both compounds were shown to possess potent antinociceptive and anti-inflammatory activity at 50 mg/kg dose, per os, without inducing any apparent acute toxicity as well as gastric damage.  相似文献   
27.
28.

Purpose

Renal cell carcinoma (RCC) accounts for approximately 80% of the primary renal cancers, and current treatment strategies are not sufficient to provide a certain solution. Since there are not many treatment options, interest in discovery of alternative drugs has increased.

Methods

In the current study, anticancer activity of a novel heterodinuclear Cu(II)–Mn(II) complex (Schiff base—SB) in combination with poly(ethylene oxide) and poly(propylene oxide) block copolymer (pluronic) P85 was tested against RCC. Cell viability, apoptosis and gene expression analysis were conducted in vitro by using Renca cells.

Results

The results revealed that the SB–P85 combination decreased cell proliferation by increasing the apoptotic gene expressions and apoptosis. Renca-injected BALB/c mice were used to mimic early stage of RCC model. Treatment with SB–P85 combination suppressed tumor formation and growth compared to baseline.

Conclusion

Overall, SB–P85 showed promising anticancer activity against RCC in vitro and in vivo.
  相似文献   
29.
30.
PurposeThe aim of this study is to analyze antimicrobial resistance and multidrug (MDR)/extensively (XDR) resistance trend among Streptococcus pneumoniae isolates causing invasive disease in adult patients.MethodsWe analyzed antimicrobial resistance and multidrug resistance trend among invasive S.pneumoniae isolates recovered from adult patients (≥18-years) in a tertiary University Hospital, Turkey between 1996 and 2018. The antibiotic susceptibility pattern was determined by using gradient-test for penicillin and cefotaxime and disk-diffusion method for other antibiotics.ResultsA total of 272 isolates (74.3% from the bloodstream) of S. pneumoniae were collected during the study period. The highest non-susceptibility rate was obtained for tetracycline (63.5%), followed by trimethoprim/sulfamethoxazole (48%), penicillin-oral (30.4%), erythromycin (21.7%), clindamycin (15.8%), ciprofloxacin/levofloxacin (5.9%), penicillin-parenteral (5.5%), cefotaxime (2.2%), and rifampisin (1.8%), respectively. No resistance was observed against vancomycin during the years studied. Over the study period, a significant increase in the rate of antimicrobial resistance among invasive pneumococcal isolates was detected with a peak at period 2014–2018. Although there was an increase in the rates of non-susceptibility to penicillin oral, parenteral penicillin, cefotaxime, erythromycin and clindamycin in adult patients, the results were not statistically significant except erythromycin. Prevalence of MDR and XDR S. pneumoniae were 29% and 9.2% respectively. When the serotypes of MDR isolates were examined, it was noted that serotype 19F (35%) and 14 (12.5%) were the most common.ConclusionsOur study showed an overall increase in non-susceptibility rates of penicillin and erythromycin in invasive S.pneumoniae isolates recovered from Turkish adult patients. Although the prevalence of MDR showed fluctuation between years, the incidence of MDR remained stable. These data indicate the necessity for continuous monitoring and assessment of serotypes and antimicrobial resistance trends in S.pneumoniae in different age groups at both the national and the regional levels as it can be affected by the serotypes dominant in that region, rational use of antibiotics and the vaccination programs.  相似文献   
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