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991.
Chen L Wong MP Cheung LK Samaranayake LP Baum L Samman N 《Cancer Genetics and Cytogenetics》2005,159(1):37-43
A fine mapping of loss of heterozygosity (LOH) was performed in oral squamous cell carcinoma (OSCC), using 12 markers on 21q11.1 approximately q21.1. We studied 43 resected primary invasive tumors and their paired normal tissues, concurrent dysplasia or carcinoma in situ in separate areas from 8 of the specimens, and 6 local recurrent carcinomas. LOH status was compared between lesions of different phases of progression within the same patient. A high frequency of LOH was observed for D21S1410, D21S120, and D21S1433 (60% each) in the primary lesions, constituting two interstitial deleted regions encompassing eight known genes. Cases showing LOH of D21S120 were significantly associated with advanced clinical stages (III and IV; P=0.02). Consistent allelic loss was observed in 64.2% of the informative cases between the precursor lesions and their corresponding invasive tumors, and in 59.5% of those between the primary lesions and their recurrent counterparts. Fewer than half of the different lesions within a given patient showed discordant allelic loss for tested markers. Our results suggest that 21q11.1 approximately q21.1 harbors tumor suppressor genes in OSCC. Genetic divergence may develop during tumor clone evolution. 相似文献
992.
Guodong Chen Shuxue Zhou Guangxin Gu Limin Wu 《Macromolecular chemistry and physics.》2005,206(8):885-892
Summary: Silica sols were first prepared based on different ratios of tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES) by an acid‐catalyzed sol–gel process, and then incorporated into acrylic‐based polyurethanes. The structures and morphologies of silicone‐oxo clusters were studied by 29Si NMR, SAXS, and scanning electron microscopy (SEM), whereas the mechanical properties of polyurethane/silica hybrids were characterized by DMA and tensile tests. The silicone‐oxo clusters in both silica sol and polyurethane hybrids became denser and larger at a higher molar ratio of TEOS/MTES and higher silica content, and the silica‐oxo clusters of polyurethane/silica hybrids even became more compact and larger than those of silica sols, increasing the elastic modulus and tensile strength of polyurethane/silica hybrids.
993.
Effective induction of immune tolerance by portal venous infusion with IL-10 gene-modified immature dendritic cells leading to prolongation of allograft survival 总被引:14,自引:0,他引:14
Zhang M Wang Q Liu Y Sun Y Ding G Fu Z Min Z Zhu Y Cao X 《Journal of molecular medicine (Berlin, Germany)》2004,82(4):240-249
Dendritic cells (DC) not only initiate T cell responses, but are also involved in the induction of tolerance. The functional properties of DC are strictly dependent on their state of maturation. It has been shown that immature DC can induce immune tolerance and prolong allograft survival. Interleukin-10 (IL-10) is an important immunosuppressive cytokine which inhibits maturation and function of DC. In order to improve the tolerogenicity of DC, we and others showed that adenovirus vectors can effectively mediate IL-10 genetic modification of DC, and IL-10 genetic modification can inhibit MHC II, B7.2, and CD40 expression, IL-12 secretion and the T cell stimulatory capacity of DC. The primary aim of this study is to examine the in vivo effects of this approach on allograft survival in a murine cardiac allograft transplantation model. To our surprise, we observed that infusion of immature DC genetically modified to express IL-10 (DC-IL-10) via the tail vein could not prolong allograft survival in the recipients, but shortened their survival. More interestingly, portal venous infusion of DC-IL-10 markedly prolonged allograft survival. The diverse effects of DC-IL-10 infusion through different routes may be due to the different immune responses to alloantigens in recipients that received DC-IL-10 via either the portal or the tail vein. Decreased cytotoxicity, polarization of Th2 response, poor T cell stimulating activity of liver DC and enhanced incidence of donor DC in the recipients may contribute to the more efficient prolongation of allograft survival observed after portal venous infusion of DC-IL-10. These results suggest that portal venous infusion may be an effective approach for immature DC to induce immune tolerance or hyporesponsiveness against donor antigens, and prolong allograft survival.Abbreviations
APC
Antigen-presenting cells
-
CTL
Cytotoxic T lymphocytes
-
DC
Dendritic cells
-
DC-IL-10
IL-10 gene-modified immature dendritic cells
-
iDC
Immature dendritic cells
-
IL-10
Interleukin-10
-
MLR
Mixed leukocyte reaction
-
MOI
Multiplicity of infection 相似文献
994.
Y.?L.?Li S.?N.?Leaw J.-H.?Chen H.?C.?Chang T.?C.?ChangEmail author 《European journal of clinical microbiology & infectious diseases》2003,22(11):693-696
A multiplex PCR method using one universal and eight species-specific primers was developed to rapidly identify eight yeast species found in positive blood cultures. The species-specific primers were designed from the internal transcribed spacer regions 1 and 2 of the rRNA gene, whereas the universal primer was located at the 26S rRNA gene. The eight species were Candida albicans, Candida glabrata, Candida guilliermondii, Candida krusei, Candida lusitaniae, Candida parapsilosis, Candida tropicalis, and Cryptococcus neoformans. The PCR products (116 to 630 bp) were different in length and could be effectively separated and recognized by polyacrylamide gel electrophoresis. By testing 234 positive blood cultures (237 isolates), 234 (98.7%) isolates of the above eight species were correctly identified by the multiplex PCR. The present method is simple to perform and can be completed within 6 h. 相似文献
995.
We present an extremely rare case of ovarian serous cystadenoma with mural nodules of rhabdomyoma. The patient, a 48-year-old woman, was admitted to our hospital with left lower abdominal pain and vaginal bleeding. A unilocular cystic tumor, measuring 13 x 10 x 10 cm, was found in her left ovary and was removed. The tumor contained clear serous fluid, approximately 600 mL, and 2 mural nodules, up to 7.5 x 5.5 x 4.5 cm. The internal cystic wall was thin for the most part and lined with ciliated cuboidal epithelium without any malignant feature. The mural part was composed of mainly more mature muscle fibers with easily discernible cross-striations, set in abundant myxoid to fibromyxoid stroma, similar to clinical and microscopic manifestations of genital rhabdomyomas reported in other sites. Because extracardiac rhabdomyoma has never been described occurring in the ovary, especially arising in serous cystadenoma, to our knowledge, this is the first case reported in the English literature. 相似文献
996.
Characterization of cortical neuron outgrowth in two- and three-dimensional culture systems 总被引:9,自引:0,他引:9
Lin PW Wu CC Chen CH Ho HO Chen YC Sheu MT 《Journal of biomedical materials research. Part B, Applied biomaterials》2005,75(1):146-157
To improve the ability of regeneration by grafting living cells or by adding growth factor to a lesion site, it is important to find good biomaterials for neuron survival and regeneration. This study focused on two- and three-dimensional cultures in a matrix using biomaterials such as agarose, collagen, fibrin, and their mixtures, because these are considered to be suitable biomaterials for neuron outgrowth. Cortical neurons were dissected from E17 rat embryos and cultured in agarose gel, collagen gel, fibrin glue, and mixtures of collagen and fibrin. Results showed that neurons cultured in collagen gel and fibrin glue had longer periods of survival (more than 3 weeks) and better neurite extension than those observed in agarose gels. As to the survival rate according to the MTT and lactate dehydrogenase assays, fibrin glue was the most suitable biomaterial for neuron survival among the biomaterials examined. With two-dimensional fibrin plating, neuron cells exhibited cell aggregation and stress fibers, but the same results were not observed with collagen gel. There were no differences in neurite extension and survival in the mixtures of collagen and fibrin. The results suggest that collagen and fibrin can provide a suitable substrate for a three-dimensional culture matrix for neuronal survival and differentiation. 相似文献
997.
Protective efficacy in chickens, geese and ducks of an H5N1-inactivated vaccine developed by reverse genetics 总被引:18,自引:0,他引:18
We generated a high-growth H5N1/PR8 virus by plasmid-based reverse genetics. The virulence associated multiple basic amino acids of the HA gene were removed, and the resulting virus is attenuated for chickens and chicken eggs. A formalin-inactivated oil-emulsion vaccine was prepared from this virus. When SPF chickens were inoculated with 0.3 ml of the vaccine, the hemagglutinin-inhibition (HI) antibody became detectable at 1 week post-vaccination (p.v.) and reached a peak of 10log2 at 6 weeks p.v. then slowly declined to 4log2 at 43 weeks p.v. Challenge studies performed at 2, 3 and 43 weeks p.v. indicated that all of the chickens were completely protected from disease signs and death. Ducks and geese were completely protected from highly pathogenic H5N1 virus challenge 3 weeks p.v. The duration of protective immunity in ducks and geese was investigated by detecting the HI antibody of the field vaccinated birds, and the results indicated that 3 doses of the vaccine inoculation in geese could induce a 34 weeks protection, while 2 doses induced more than 52 weeks protection in ducks. We first reported that an oil-emulsion inactivated vaccine derived from a high-growth H5N1 vaccine induced approximately 10 months of protective immunity in chickens and demonstrated that the oil-emulsion inactivated avian influenza vaccine is immunogenic for geese and ducks. These results provide useful information for the application of vaccines to the control of H5N1 avian influenza in poultry, including chickens and domestic waterfowl. 相似文献
998.
Entrainment of Intestinal Slow Waves with Electrical Stimulation Using Intraluminal Electrodes 总被引:3,自引:0,他引:3
The aim of this study was to investigate whether the intestinal stimulation would be feasible using a less invasive method: intraluminal electrodes. The study was performed in nine healthy hound dogs (15–26 kg). Four pairs of electrodes were implanted on the serosa of the jejunum at an interval of 5 cm with the most proximal pair 35 cm beyond the pylorus. An intestinal fistula was made 20 cm beyond the pylorus. Simultaneous recordings of intestinal myoelectrical activity were made for 2 h in the fasting state from both intraluminal and serosal electrodes. Various pacing parameters were tested. The frequency of the intestinal slow wave recorded from the intraluminal electrodes was identical to that from the serosal electrodes
, p < 0.001), and so was the percentage of normal 17–22 cycles/min waves (95.8±33.9% vs 98.16±1.33%, r=0.96, p<0.01).p < 0.01). A complete entrainment of the intestinal slow wave was achieved in every dog with electrical stimulation using intraluminal ring electrodes. The effective pacing parameters were pulse width of 70 ms, amplitude of 4 mA and frequency of 1.1 IF (intrinsic frequency). The time required for the entrainment of the intestinal slow wave with intraluminal pacing was 25.0±2.1s. The maximum driven frequency was found to be 1.43±0.01 IF. The results reveal that intraluminal pacing is an effective and efficient method for the entrainment of intestinal slow waves. It may become a potential approach for the treatment of intestinal motor disorders associated with myoelectrical abnormalities. © 2000 Biomedical Engineering Society.
PAC00: 8754Dt, 8719Ff, 8717Nn 相似文献
999.
Interleukin-1 and tumor necrosis factor receptor signaling is not required for bacteria-induced osteoclastogenesis and bone loss but is essential for protecting the host from a mixed anaerobic infection 下载免费PDF全文
Bacterial infection causes significant morbidity, mediated in part by the up-regulation of inflammatory cytokines. Cytokine induction is thought to stimulate osteolysis in conditions such as periodontal disease and otitis media. To establish the relative importance of interleukin-1 (IL-1) and tumor necrosis factor (TNF) in mediating the response to a mixed anaerobic infection, we used an in vivo model in which the dental pulp was inoculated with six anaerobic pathogens, in mice with functional deletions of receptors to IL-1 (IL-1RI(-/-)), TNF (TNFRp55(-/-)-p75(-/-)), or both (TNFRp55(-/-)-IL-1RI(-/-)). Polymorphonuclear and mononuclear phagocyte recruitment occurred to the greatest extent in TNFRp55(-/-)-IL-1RI(-/-) mice, and to a lesser extent in IL-1RI(-/-) or TNFRp55(-/-)-p75(-/-) mice, and the least in wild-type mice, demonstrating that recruitment of these phagocytes is not dependent on IL-1 or TNF receptor signaling. A similar pattern was observed for bacterial penetration into host tissue. Because it had recently been reported that TNF played a critical role in mediating lipopolysaccharide-induced bone loss, we anticipated that mice with targeted deletions of TNFRp55(-/-) would have reduced osteoclastogenesis. Surprisingly, osteolytic lesion formation was greatest in animals lacking TNF and/or IL-1 receptors. These results indicate that IL-1 or TNF receptor signaling is not required for bacteria-induced osteoclastogenesis and bone loss, but does play a critical role in protecting the host against mixed anaerobic infections. 相似文献
1000.
目的:为设计阴部外动脉阴茎皮瓣转位尿道成形术提供依据。方法:30侧经动脉内灌注红色乳胶的成人尸体,解剖观测阴部外动脉起始、行程;着重阴部外动脉阴茎支在阴茎的走行、分支分布。结果:阴部外动脉始于股动脉,外径1.8±0.4mm,伴行静脉1-2支,汇入大隐静脉。阴茎支可视为本干的延续,经耻骨结节两侧靠近阴茎,分别经2(10)点、3(9)点和1(11)点进入阴茎,多数分出背侧支、腹侧支分布阴茎皮肤。外径0.8±0.2mm。结论:阴茎皮肤血管恒定,以阴茎支为蒂,可在阴茎外侧或背外侧、腹外侧设计皮瓣,用于尿道成形术。术式已在临床应用,效果满意。 相似文献