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191.
192.
Chacham AS  Maia MB  Greco M  Silva AP  Greco DB 《AIDS care》2007,19(Z1):S12-S22
In Brazil in the last decade there has been an increase in the susceptibility of young women to HIV. This study explored the link between autonomy, or control over major domains of economic, social and sexual life, and susceptibility to HIV infection among poor young women living in an urban slum area of Brazil. A cross-sectional survey was carried out on a random sample of 356 young women between 15 and 24 years old. The study found that indicators of autonomy that relate to sexuality, mobility and freedom from threat by partners were significantly correlated with practices linked to HIV prevention and with access to health services promoting prevention, especially among adolescents. Young women who talked to their partner about condom use before first intercourse and co-decided with them on condom use were more likely to use condoms. In contrast, those who had ever been victim of physical violence by a partner or whose partners restricted their mobility were less likely to use condoms. The study found that young women were more likely to have accessed health services for gynaecological examinations, family planning services and HIV testing if they had ever been pregnant. The findings indicate that structural gender inequalities translate into unequal relationships and reduced autonomy, increasing young women's susceptibility to HIV. A bias in HIV testing and reproductive health services towards pregnant women leaves many susceptible youth without early access. The study suggests the development of a reproductive health policy that ensures that young women access services before they get pregnant and that also reaches young males.  相似文献   
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194.
Unverricht–Lundborg disease (EPM1), the most common progressive myoclonic epilepsy, is associated with a defect of cystatin B (CSTB), a protease inhibitor. We used CSTB knockout mice to test the hypothesis that EPM1 onset is related to a latent hyperexcitability and that progression depends on higher susceptibility to seizure-induced cell damage. Hippocampal slices prepared from CSTB-deficient mice were hyperexcitable, as they responded to afferent stimuli in CA1 with multiple population spikes and kainate perfusion provoked the appearance of epileptic-like activity earlier than in WT mice. This hyperexcitability may depend on loss of inhibition, because the density of GABA-immunoreactive cells was reduced in the hippocampus of CSTB knockouts. In vivo, CSTB-deficient mice treated with kainate displayed increased susceptibility to seizures, with shorter latency to seizure onset and increased seizure severity compared with WT littermates. Furthermore, a greater degree of neuronal damage was observed in CSTB-deficient than in WT mice after seizures of identical grade, indicating increased susceptibility to seizure-induced cell death.  相似文献   
195.
The aim of this study was to determine the validity and reliability of a Portuguese version of the Postpartum Depression Screening Scale (PDSS). A total of 120 new mothers completed the translated version of PDSS and later were interviewed using the Structured Clinical Interview for DSM-IV Axis I Disorders, our gold standard for clinical status. The best cut-off score for the Portuguese version was 102, with a sensibility of 94%, a specificity of 95%, a positive predictive value of 75% and a negative predictive value of 99%. Reliability, measured by the alpha coefficient of internal consistency, was .95. The PDSS is considered ready for use in the screening of Brazilian new mothers for postpartum depression.  相似文献   
196.
Malaria is one of the most important tropical diseases and mainly affects populations living in developing countries. Reduced sensitivity of Plasmodium sp. to formerly recommended antimalarial drugs places an increasing burden on malaria control programs as well as on national health systems in endemic countries. The present study aims to evaluate the antimalarial activity of betulinic acid and its derivative compounds, betulonic acid, betulinic acid acetate, betulinic acid methyl ester, and betulinic acid methyl ester acetate. These substances showed antiplasmodial activity against chloroquine-resistant Plasmodium falciparum parasites in vitro, with IC50 values of 9.89, 10.01, 5.99, 51.58, and 45.79 μM, respectively. Mice infected with Plasmodium berghei and treated with betulinic acid acetate had a dose-dependent reduction of parasitemia. Our results indicate that betulinic acid and its derivative compounds are candidates for the development of new antimalarial drugs.  相似文献   
197.

Ethnopharmacological relevance

Peperomia serpens (Piperaceae), popularly known as “carrapatinho”, is an epiphyte herbaceous liana grown wild on different host trees in the Amazon rainforest. Its leaves are largely used in Brazilian folk medicine to treat inflammation, pain and asthma.

Aim of the study

This study investigated the effects of essential oil of Peperomia serpens (EOPs) in standard rodent models of pain and inflammation.

Materials and methods

The antinociceptive activity was evaluated using chemical (acetic acid and formalin) and thermal (hot plate) models of nociception in mice whereas the anti-inflammatory activity was evaluated by carrageenan- and dextran-induced paw edema tests in rats croton oil-induced ear edema, as well as cell migration, rolling and adhesion induced by carrageenan in mice. Additionally, phytochemical analysis of the EOPs has been also performed.

Results

Chemical composition of the EOPs was analyzed by gas chromatography and mass spectrometry (GC/MS). Twenty-four compounds, representing 89.6% of total oil, were identified. (E)-Nerolidol (38.0%), ledol (27.1%), α-humulene (11.5%), (E)-caryophyllene (4.0%) and α-eudesmol (2.7%) were found to be the major constituents of the oil. Oral pretreatment with EOPs (62.5-500 mg/kg) significantly reduced the writhing number evoked by acetic acid injection, with an ED50 value of 188.8 mg/kg that was used thereafter in all tests. EOPs had no significant effect on hot plate test but reduced the licking time in both phases of the formalin test, an effect that was not significantly altered by naloxone (0.4 mg/kg, s.c.). EOPs inhibited the edema formation induced by carrageenan and dextran in rats. In mice, EOPs inhibited the edema formation by croton oil as well as the leukocyte and neutrophil migration, the rolling and the adhesion of leukocytes.

Conclusions

These data show for the first time that EOPs has a significant and peripheral antinociceptive effect that seems unrelated to interaction with the opioid system. EOPs also displays a significant anti-inflammatory effect in acute inflammation models. This effect seems to be related to components which inhibit the production of several inflammatory mediators. These results support the widespread use of Peperomia serpens in popular medicine to treat inflammation and pain.  相似文献   
198.
4‐Nerolidylcatechol (4‐NC) isolated from Piper peltatum L. (Piperaceae) was evaluated for in vitro antiplasmodial activity against Plasmodium falciparum (cultures of both standard CQR (K1) and CQS (3D7) strains and two Amazonian field isolates) and for in vivo antimalarial activity using the Plasmodium berghei‐murine model. 4‐NC exhibits significant in vitro and moderate in vivo antiplasmodial activity. 4‐NC administered orally and subcutaneously at doses of 200, 400 and 600 mg/kg/day suppressed the growth of P. berghei by up to 63% after four daily treatments (days 1–4). Also, 4‐NC exhibited important in vitro antiplasmodial activity against both standard and field P. falciparum strains in which 50% inhibition of parasite growth (IC50) was produced at concentrations of 0.05–2.11 μg/mL and depended upon the parasite strain. Interestingly, healthy (non‐infected) mice that received 4‐NC orally presented (denatured) blood plasma which exhibited significant in vitro activity against P. falciparum. This is evidence that mouse metabolism allows 4‐NC or active metabolites to enter the blood. Further chemical and pharmacological studies are necessary to confirm the potential of 4‐NC as a new antimalarial prototype. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
199.
Carter M  O'Keefe JH 《Mayo Clinic proceedings. Mayo Clinic》2008,83(11):1294; author reply 1294-1294; author reply 1296
  相似文献   
200.
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