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31.
Endothelial cells of the pulmonary circulation are equipped with an ectoenzyme protease system on their luminal surface. The
membrane-bound proteases act on the circulating polypeptides and cleave certain peptide bonds in their structure, thus modifying
their biological properties. We studied the enzyme dipeptidyl peptidase IV (DP-IV) in mammalian lungs in order to elucidate
its contribution to the aforementioned proteolytic processing. We have found that lungs of mammalian species posses DP-IV
with different levels of specific activity. In rat lungs the specific activity of DP-IV progressively increased during development
between the 18th fetal and the 70th postnatal days. Human embryonal and fetal lungs had significantly higher specific activity
of DP-IV compared with the lungs of adult individuals. The enzyme in lungs was mainly membrane bound and was solubilized by
some detergents, but not with papain and trypsin. The Triton X-100-solubilized DP-IV from rat lung lysosomal-microsomal membranes
migrated during electrophoresis on continuous 4–30% gradient polyacrylamide gel at native apparent Mr values of 260 000 and 490 000. Using a histochemical technique we found the enzyme activity of DP-IV in the capillary bed
of the lung alveolar septa only. Four aminoacyl-L-proline-4-nitroanilide substrates for DP-IV were cleaved rapidly during
one passage through isolated perfused blood-free rat lungs. The perfusion profiles of cleavage of these substrates were largely
coincident with that of Blue Dextran 2 000, a compound, which is unlikely to leave the intravascular space. Taken together,
the data suggest that DP-IV operates in vivo as a membrane-bound ectoenzyme on the luminal surface of pulmonary endothelial
cells and that it may cleave certain circulating polypeptides. 相似文献
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33.
Michael Zech MD Robert Jech MD PhD Sylvia Boesch MD Matej Škorvánek MD PhD Ján Necpál MD Jana Švantnerová MD Matias Wagner MD Ariane Sadr-Nabavi PhD Felix Distelmaier MD Martin Krenn MD PhD Tereza Serranová MD PhD Irena Rektorová MD PhD Petra Havránková MD PhD Alexandra Mosejová MD Iva Příhodová MD PhD Jana Šarláková MD Kristína Kulcsarová MD Olga Ulmanová MD PhD Karel Bechyně MD Miriam Ostrozovičová MD Vladimír Haň MD PhD Joaquim Ribeiro Ventosa MD Theresa Brunet MD Riccardo Berutti PhD Mohammad Shariati MD Ali Shoeibi MD Susanne A. Schneider MD Alice Kuster MD Matthias Baumann MD David Weise MD Friederike Wilbert MD Wibke G. Janzarik MD Matthias Eckenweiler MD Volker Mall MD Bernhard Haslinger MD Steffen Berweck MD Juliane Winkelmann MD Konrad Oexle MD 《Movement disorders》2021,36(8):1959-1964
34.
Zemlyanova M. A. Zaitseva N. V. Ignatova A. M. Stepankov M. S. Toropov L. I. Kol’dibekova Yu. V. 《Bulletin of experimental biology and medicine》2021,170(5):665-668
Bulletin of Experimental Biology and Medicine - In female Wistar rats, we studied the effects of daily 20-day administration of intragastric suspension of nanosized calcium oxide on hematological... 相似文献
35.
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Matteo Brucoli Paolo Boffano Irene Romeo Chiara Corio Arnaldo Benech Muhammad Ruslin Tymour Forouzanfar Thomas Starch‐Jensen Tanía Rodríguez‐Santamarta Juan Carlos de Vicente Johanna Snll Hanna Thorn Marko Tarle Emil Dediol Petia Pechalova Nikolai Pavlov Hristo Daskalov Iva Doykova Kadri Kelemith Tiia Tamme Andrey Kopchak Ievgen Shumynskyi Pierre Corre Helios Bertin Quentin Goguet Marine Anquetil Aurlien Louvrier Christophe Meyer Tadej Dovak David Vozli
Ane Birk Boban Ani
i Vitomir S. Konstantinovic 《Dental traumatology》2020,36(3):241-246
37.
Proapoptotic N-truncated BCL-xL protein activates endogenous mitochondrial channels in living synaptic terminals
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Jonas EA Hickman JA Chachar M Polster BM Brandt TA Fannjiang Y Ivanovska I Basañez G Kinnally KW Zimmerberg J Hardwick JM Kaczmarek LK 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(37):13590-13595
Neuronal death is often preceded by functional alterations at nerve terminals. Anti- and proapoptotic BCL-2 family proteins not only regulate the neuronal death pathway but also affect excitability of healthy neurons. We found that exposure of squid stellate ganglia to hypoxia, a death stimulus for neurons, causes a cysteine protease-dependent loss of full-length antiapoptotic BCL-xL, similar to previous findings in mammalian cells. Therefore, to determine the direct effect of the naturally occurring proapoptotic cleavage product of BCL-xL on mitochondria, recombinant N-truncated BCL-xL was applied to mitochondria inside the squid presynaptic terminal and to purified mitochondria isolated from yeast. N-truncated BCL-xL rapidly induced large multi-conductance channels with a maximal conductance significantly larger than those produced by full-length BCL-xL. This activity required the hydrophobic C terminus and the BH3 domain of BCL-xL. Moreover, N-truncated BCL-xL failed to produce any channel activity when applied to plasma membranes, suggesting that a component of the mitochondrial membrane is necessary for its actions. Consistent with this idea, the large channels induced by N-truncated BCL-xL are inhibited by NADH and require the presence of VDAC, a voltage-dependent anion channel present in the outer mitochondrial membrane. These observations suggest that the mitochondrial channels specific to full-length and N-truncated BCL-xL contribute to their opposite effects on synaptic transmission, and are consistent with their opposite effects on the cell death pathway. 相似文献
38.
Aysheshm Kassahun Jovana Sadlova Vit Dvorak Tatiana Kostalova Iva Rohousova Daniel Frynta Tatiana Aghova Daniel Yasur-Landau Wessenseged Lemma Asrat Hailu Gad Baneth Alon Warburg Petr Volf Jan Votypka 《Acta tropica》2015
Human visceral (VL, also known as Kala-azar) and cutaneous (CL) leishmaniasis are important infectious diseases affecting countries in East Africa that remain endemic in several regions of Ethiopia. The transmission and epidemiology of the disease is complicated due to the complex life cycle of the parasites and the involvement of various Leishmania spp., sand fly vectors, and reservoir animals besides human hosts. Particularly in East Africa, the role of animals as reservoirs for human VL remains unclear. Isolation of Leishmania donovani parasites from naturally infected rodents has been reported in several endemic countries; however, the status of rodents as reservoirs in Ethiopia remains unclear. Here, we demonstrated natural Leishmania infections in rodents. Animals were trapped in 41 localities of endemic and non-endemic areas in eight geographical regions of Ethiopia and DNA was isolated from spleens of 586 rodents belonging to 21 genera and 38 species. Leishmania infection was evaluated by real-time PCR of kinetoplast (k)DNA and confirmed by sequencing of the PCR products. Subsequently, parasite species identification was confirmed by PCR and DNA sequencing of the 18S ribosomal RNA internal transcribed spacer one (ITS1) gene. Out of fifty (8.2%) rodent specimens positive for Leishmania kDNA-PCR and sequencing, 10 were subsequently identified by sequencing of the ITS1 showing that five belonged to the L. donovani complex and five to L. tropica. Forty nine kDNA-positive rodents were found in the endemic localities of southern and eastern Ethiopia while only one was identified from northwestern Ethiopia. Moreover, all the ten ITS1-positive rodents were captured in areas where human leishmaniasis cases have been reported and potential sand fly vectors occur. Our findings suggest the eco-epidemiological importance of rodents in these foci of leishmaniasis and indicate that rodents are likely to play a role in the transmission of leishmaniasis in Ethiopia, possibly as reservoir hosts. 相似文献
39.
Nilgun Gurbuz Arif Kol Tumay Ipekci Erhan Ates Asli Baykal Mustafa F Usta 《Asian journal of andrology》2015,17(5):797-801
The relationship between erectile dysfunction (ED) and chronic renal failure (CRF) has been reported in several studies. This study aimed to investigate whether the chronic use of sildenafil could enhance the erectile capacity in CRF-induced rats. In addition, we assessed the effect of that treatment on certain molecules, which have been suggested to play crucial roles in erectile physiology and CRF-related ED as well. Three groups of animals were utilized: (1) age-matched control rats, (2) CRF-induced rats, (3) CRF-induced rats treated with chronic administration of sildenafil (5 mg kg−1 p.o. for 6 weeks [treatment started after 6 weeks of CRF induction]). At 3 months, all animals underwent cavernosal nerve stimulation (CNS) to assess erectile function. Penile tissue advanced glycation end products (AGE''s)/5-hydroxymethyl-2-furaldehyde, malondialdehyde (MDA), cGMP (ELISA), inducible nitric oxide synthase (iNOS) and neuronal NOS (nNOS) (Western blot) analyses were performed in all rat groups. CRF-induced rats had a significant decrease in erectile function when compared to control rats (P < 0.05). The increase in both intracavernosal pressure (ICP) and area under the curve of CRF-induced rats treated with sildenafil (Group 3) was greater than CRF-induced rats (Group 2). Additionally, sildenafil treatment decreased AGE, MDA and iNOS levels, while it preserved nNOS and cGMP contents in CRF-induced penile tissue. Decreased AGE, MDA, iNOS and increased nNOS, cGMP levels at the sildenafil-treated group increased both ICP and Total ICP to CNS, which led to improve erectile function in CRF-induced rats. The results of the present study revealed the therapeutic effect of chronic sildenafil administration on erectile function in CRF-induced rats. 相似文献
40.