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991.
AIM: Lafutidine, a histamine H2 receptor antagonist, exhibits gastro-protective action mediated by capsaicin-sensitive afferent neurons (CSN). We compared the effect between lafutidine and capsaicin, with respect to the interaction with endogenous prostaglandins (PG), nitric oxide (NO) and the afferent neurons, including transient receptor potential vanilloid subtype 1 (TRPV1). METHODS: Male SD rats and C57BL/6 mice, both wild-type and prostacyclin IP receptor knockout animals, were used after 18 h of fasting. Gastric lesions were induced by the po administration of HCI/ethanol (60% in 150 mmol/L HCI) in a volume of 1 mL for rats or 0.3 mL for mice. RESULTS: Both lafutidine and capsaicin (1-10 mg/kg, po) afforded dose-dependent protection against HCI/ ethanol in rats and mice. The effects were attenuated by both the ablation of CSN and pretreatment with NG-nitro-L-arginine methyl ester, yet only the effect of capsaicin was mitigated by prior administration of capsazepine, the TRPV1 antagonist, as well as indomethacin. Lafutidine protected the stomach against HCI/ethanol in IP receptor knockout mice, similar to wild-type animals, while capsaicin failed to afford protection in the animals lacking IP receptors. Neither of these agents affected the mucosal PGE2 or 6-keto PGF1αcontents in rat stomachs. Capsaicin evoked an increase in [Ca2 ]i in rat TRPV1-transfected HEK293 cells while lafutidine did not. CONCLUSION: These results suggest that although both lafutidine and capsaicin exhibit gastro-protective action mediated by CSN, the mode of their effects differs regarding the dependency on endogenous PGs/IP receptors and TRPV1. It is assumed that lafutidine interacts with CSN at yet unidentified sites other than TRPV1. 相似文献
992.
Takaaki Konuma Satoshi Takahashi Jun Ooi Akira Tomonari Nobuhiro Tsukada Seiko Kato Aki Sato Fumihiko Monma Senji Kasahara Tokiko Nagamura-Inoue Kaoru Uchimaru Tohru Iseki Arinobu Tojo Takuhiro Yamaguchi Shigetaka Asano 《Annals of hematology》2009,88(6):581-588
Increasing recipient age is a well-known risk factor for graft-versus-host disease (GVHD) and treatment-related mortality
(TRM) and has a negative impact on allogeneic hematopoietic stem cell transplantation. Since the incidence of severe GVHD
after cord blood transplantation (CBT) is lower than that after transplants using bone marrow or mobilized peripheral blood
grafts from adult cells, we should expect better outcomes from CBT in older patients. To evaluate the feasibility and efficacy
of myeloablative unrelated CBT in patients aged between 50 and 55 years, we performed a retrospective comparison of 100 patients
with acute leukemia who received cord blood grafts at our institution. Nineteen older patients (median age, 52; range, 50–55)
and 81 younger patients (median, 36; range, 16–49) received a myeloablative conditioning regimen including 12 Gy of total
body irradiation and chemotherapy. GVHD prophylaxis included cyclosporine with (n = 96) or without (n = 4) methotrexate. There were no significant differences in the incidences of grades II to IV acute GVHD, extensive-type
chronic GVHD, TRM, and the probability of overall and disease-free survival between these groups. These results suggest that,
in patients with acute leukemia, myeloablative CBT might be as safe and effective in patients aged between 50 and 55 years
as in younger patients. 相似文献
993.
Rapid hepatic fate specification of adipose-derived stem cells and their therapeutic potential for liver failure 总被引:2,自引:0,他引:2
Banas A Teratani T Yamamoto Y Tokuhara M Takeshita F Osaki M Kato T Okochi H Ochiya T 《Journal of gastroenterology and hepatology》2009,24(1):70-77
Background and Aim: Multipotential mesenchymal stem cells (MSC), present in many organs and tissues, represent an attractive tool for the establishment of a successful stem cell-based therapy in the field of regeneration medicine. Adipose tissue mesenchymal stem cells (AT-MSC), known as adipose-derived stem cells (ASC) are especially attractive in the context of future clinical applications because of their high accessibility and minimal invasiveness during the procedure to obtain them. The goal of the present study was to induce human ASC into functional hepatocytes in vitro within a very short period of time and to check their therapeutic potential in vivo .
Methods: In vitro generated ASC-derived hepatocytes were checked for hepatocyte-specific markers and functions. Afterwards, they were transplanted into nude mice with liver injury. Twenty-four hours after transplantation, biochemical parameters were evaluated in blood serum.
Results: We have shown here that ASC can be differentiated into hepatocytes within 13 days and can reach the functional properties of primary human hepatocytes. After transplantation into mice with acute liver failure, ASC-derived hepatocytes can restore such liver functions as ammonia and purine metabolism. Markers of liver injury, alanine aminotransferase, aspartate aminotransferase, as well as ammonia, were decreased after ASC-derived hepatocyte transplantation.
Conclusions: Our data highlight the properties of ASC as having a special affinity for hepatocyte differentiation in vitro and liver regeneration in vivo . Thus, ASC may be a superior choice for the establishment of a therapy for injured liver. 相似文献
Methods: In vitro generated ASC-derived hepatocytes were checked for hepatocyte-specific markers and functions. Afterwards, they were transplanted into nude mice with liver injury. Twenty-four hours after transplantation, biochemical parameters were evaluated in blood serum.
Results: We have shown here that ASC can be differentiated into hepatocytes within 13 days and can reach the functional properties of primary human hepatocytes. After transplantation into mice with acute liver failure, ASC-derived hepatocytes can restore such liver functions as ammonia and purine metabolism. Markers of liver injury, alanine aminotransferase, aspartate aminotransferase, as well as ammonia, were decreased after ASC-derived hepatocyte transplantation.
Conclusions: Our data highlight the properties of ASC as having a special affinity for hepatocyte differentiation in vitro and liver regeneration in vivo . Thus, ASC may be a superior choice for the establishment of a therapy for injured liver. 相似文献
994.
995.
996.
997.
Toshiki Uchihara Ayako Nakamura Katsuhiko Shibuya Saburo Yagishita 《Brain pathology (Zurich, Switzerland)》2011,21(2):180-188
Immunohistochemisty with RD3, a monoclonal antibody specific for three‐repeat (3R) tau, is sometimes hampered by diffuse neuronal staining on formalin‐fixed, paraffin‐embedded sections pretreated with formic acid and heating. Additional pretreatment with potassium permanganate followed by oxalic acid completely eliminated this diffuse RD3‐immunoreactivity (IR) in neurons. Furthermore, this additional pretreatment uniformly enhanced RD3‐IR, as well as RD4‐IR, a monoclonal antibody specific for four‐repeat (4R) tau, on pathological deposits with tau IR. This enhanced sensitivity and specificity may allow more reliable identification of 3R and 4R tau in pathological deposits, which may be variable dependent on disease and regions. Cerebral cortex and midbrain from 8 patients [5 progressive supranuclear palsy (PSP) and 3 corticobasal degeneration (CBD)] were screened for RD3‐ and RD4‐IR with this improved procedure. In addition to RD4‐positive structures found both in cerebral cortex and brainstem, RD3‐positive neurofibrillary tangles (NFTs) were also found in midbrain in 7 of these 8 cases but not in the cortex. Multi‐labeling study demonstrated that most of RD3‐negative neurons were positive for RD4. This reliable demonstration of pathological 3R tau deposits in the brainstem of PSP/CBD, so far presumably characterized by deposition of 4R tau, is useful to map tau‐positive lesions according to their biochemical composition. 相似文献
998.
Kawai T Takahashi K Sato S Coban C Kumar H Kato H Ishii KJ Takeuchi O Akira S 《Nature immunology》2005,6(10):981-988
999.
Sugauchi F Mizokami M Orito E Ohno T Kato H Maki M Suzuki H Ojika K Ueda R 《Journal of medical virology》2000,62(4):456-462
A seroepidemiological study of HBV infection was carried out to investigate the seroprevalence of hepatitis B surface antigen (HBsAg) and the transmission routes of hepatitis B virus (HBV) infection among residents of a nursing home for the elderly. HBV serum markers were examined in 119 residents and 71 healthcare workers in the institution, as also in 1330 healthy subjects from the same geographical area, as the control group. HBsAg was detected in 6 (5%), 0 and 20 (1.5%) residents, healthcare workers and healthy subjects, respectively. Four residents (A-D) who had HBV-DNA in the serum were studied by molecular evolutionary analysis. The strains derived from residents A, B and D were clustered together within a close range of evolutionary distances. Residents B and D, who were not positive for HBsAg at the time of admission to the institution, subsequently became HBsAg-positive asymptomatic carriers. These results suggested intrainstitutional transmission of HBV in the nursing home for the elderly, and confirmed that the source of transmission of HBV to residents B and D was resident A who was positive for HBsAg. Residents in a nursing home for the elderly should be considered as being a high-risk group for HBV infection, and vaccination against HBV of these groups is recommended. 相似文献
1000.
Koichiro Irie Takaaki Tomofuji Daisuke Ekuni Yasumasa Endo Kenta Kasuyama Tetsuji Azuma Naofumi Tamaki Toshiki Yoneda Manabu Morita 《Archives of oral biology》2014