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971.
Ephantus J. Muturi Luna Kamau Benjamin G. Jacob Simon Muriu Charles M. Mbogo Josephat Shililu John Githure Robert J. Novak 《Parasitology research》2009,105(4):1041-1046
Studies were conducted to determine the role of sibling species of Anopheles funestus complex in malaria transmission in three agro-ecosystems in central Kenya. Mosquitoes were sampled indoors and outdoors,
and rDNA PCR was successfully used to identify 340 specimens. Anopheles parensis (91.8%), A. funestus (6.8%), and Anopheles leesoni (1.5%) were the three sibling species identified. A. parensis was the dominant species at all study sites, while 22 of 23 A. funestus were collected in the non-irrigated study site. None of the 362 specimens tested was positive for Plasmodium falciparum circumsporozoite proteins by enzyme-linked immunosorbent assay. The most common blood-meal sources (mixed blood meals included)
for A. parensis were goat (54.0%), human (47.6%), and bovine (39.7%), while the few A. funestus s.s. samples had fed mostly on humans. The human blood index (HBI) for A. parensis (mixed blood meals included) in the non-irrigated agro-ecosystem was 0.93 and significantly higher than 0.33 in planned rice
agro-ecosystem. The few samples of A. funestus s.s. and A. funestus s.l. also showed a trend of higher HBI in the non-irrigated agro-ecosystem. We conclude that agricultural practices have
significant influence on distribution and blood feeding behavior of A. funestus complex. Although none of the species was implicated with malaria transmission, these results may partly explain why non-irrigated
agro-ecosystems are associated with higher risk of malaria transmission by this species compared to irrigated agro-ecosystems. 相似文献
972.
Rozany Mucha Dufloth M.D. Ph.D. Jacy Maria Alves M.S. Diana Martins B.Sc. Daniella Serafin Couto Vieira M.D. M.Sc. Horácio Chikota M.D. Luiz Carlos Zeferino M.D. Ph.D. Fernando Schmitt M.D. Ph.D. F.I.A.C. 《Diagnostic cytopathology》2009,37(11):809-814
Breast carcinoma is a heterogeneous disease. It can be classified into phenotypes based on the expression of certain proteins, with distinct differences in prognosis. The basal phenotype is associated with worse prognosis and it still remains without specific treatment. However, there is currently no international consensus on the cytological criteria that could predict this phenotype. The purpose of the study was to evaluate the cytological criteria in fine‐needle aspiration biopsy and to identify their association with the basal phenotype of breast carcinoma. Fine‐needle aspiration biopsy specimens and tissue sections (mastectomy specimen) from 74 cases of high‐grade invasive ductal breast carcinomas were consecutively retrieved from the files of three institutions. Breast carcinomas were studied using the tissue microarray technique, being classified into phenotypes: luminal A, luminal B, HER2 overexpression, and basal. The cytological criteria for all cases were reviewed blindly by two pathologists according to five cytological criteria: cellularity, cell pattern, presence of necrosis, nucleoli, and nuclear atypia. Exact Fisher test was used to test the association between cytological criteria and the phenotypes of breast carcinoma. Necrosis was present in 64.7% of basal breast carcinomas, and 31.1% of nonbasal breast carcinomas, and that result was statistically significant, showing an odds ratio (OR) of 3.80. The basal phenotype, compared with the luminal A, showed more necrosis (OR = 6.97), present/prominent nucleoli (OR = 8.18), and cellularity more frequently (OR = 18.03). Necrosis, as well as present/prominent nucleoli and abundant cellularity are criteria more frequently associated to the basal phenotype of breast carcinoma. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
973.
Shmuel Y. Mahgerefteh Arye Blachar Shifra Fraifeld Jacob Sosna 《Current colorectal cancer reports》2011,7(1):71-79
In the setting of CT colonography (CTC), decreasing bowel preparation measures may help to optimize colorectal cancer screening
compliance without compromising accuracy. Decreased-purgation or wholly noncathartic CTC, known as nonconventional CTC, may
be accomplished in conjunction with fecal tagging. Image post-processing technologies such as electronic cleansing and computer-aided
detection may boost accuracy and decrease the need for bowel preparation even further. We review pre-study preparation and
image post-processing techniques that have been described in nonconventional-preparation CTC studies over the past 10 years.
We explore in detail specific aspects of nonconventional cathartic and fecal tagging regimens, including substance, dose,
and time frame of ingestion. 相似文献
974.
Ram Dixit Brian Barnett Jacob E. Lazarus Mariko Tokito Yale E. Goldman Erika L. F. Holzbaur 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(2):492-497
Microtubules are polarized polymers that exhibit dynamic instability, with alternating phases of elongation and shortening, particularly at the more dynamic plus-end. Microtubule plus-end tracking proteins (+TIPs) localize to and track with growing microtubule plus-ends in the cell. +TIPs regulate microtubule dynamics and mediate interactions with other cellular components. The molecular mechanisms responsible for the +TIP tracking activity are not well understood, however. We reconstituted the +TIP tracking of mammalian proteins EB1 and CLIP-170 in vitro at single-molecule resolution using time-lapse total internal reflection fluorescence microscopy. We found that EB1 is capable of dynamically tracking growing microtubule plus-ends. Our single-molecule studies demonstrate that EB1 exchanges rapidly at microtubule plus-ends with a dwell time of <1 s, indicating that single EB1 molecules go through multiple rounds of binding and dissociation during microtubule polymerization. CLIP-170 exhibits lattice diffusion and fails to selectively track microtubule ends in the absence of EB1; the addition of EB1 is both necessary and sufficient to mediate plus-end tracking by CLIP-170. Single-molecule analysis of the CLIP-170–EB1 complex also indicates a short dwell time at growing plus-ends, an observation inconsistent with the copolymerization of this complex with tubulin for plus-end-specific localization. GTP hydrolysis is required for +TIP tracking, because end-specificity is lost when tubulin is polymerized in the presence of guanosine 5′-[α,β-methylene]triphosphate (GMPCPP). Together, our data provide insight into the mechanisms driving plus-end tracking by mammalian +TIPs and suggest that EB1 specifically recognizes the distinct lattice structure at the growing microtubule end. 相似文献
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