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71.
Jung-Fa Tsai Wen-Yu Chang Jen-Eing Jeng Mei-Shang Ho Zu-Yau Lin Juei-Hsiung Tsai 《Journal of medical virology》1994,44(1):92-95
A case control study consisting of 102 patients with HCC, 102 sex-matched and age-matched patients with nonhepatic disease, and 204 matched healthy controls was carried out to investigate the effect of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection on the development of hepatocellular carcinoma (HCC). The prevalence of antibody to HCV (anti-HCV) in HCC (34.3%) was higher than in nonhepatic disease (10.7%, P< 0.001) or in healthy controls (2.4%, P< 0.001). The prevalence of hepatitis B surface antigen (HBsAg) in HCC (77.4%) was higher than in nonhepatic disease (16.6%, P< 0.001) or in healthy controls (19.6%, P< 0.001). Anti-HCV positivity in nonhepatic disease was higher than in healthy controls (P<0.01). Using patients with nonhepatic disease as controls, stepwise logistic regression analysis indicated that both anti-HCV (odds ratio, 3.4; 95% confidence interval, 2.1-5.6) and HBsAg (odds ratio, 5.6; 95% confidence interval, 3.6–8.5) are independent risk factors for HCC. Using healthy controls, the development of HCC was also strongly associated with anti-HCV (odds ratio, 8.0; 95% confidence interval, 4.3–14.6) and HBsAg (odds ratio, 5.5; 95% confidence interval, 3.7–8.2). Calculation of incremental odds ratio indicated that there is no interaction between HBV and HCV. In conclusion, HBV and HCV are risk factors of HCC. They act independently and without interaction. © 1994 Wiley-Liss, Inc. 相似文献
72.
Lin FY Liu CI Liu YL Zhang Y Wang K Jeng WY Ko TP Cao R Wang AH Oldfield E 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(50):21337-21342
"Head-to-head" terpene synthases catalyze the first committed steps in sterol and carotenoid biosynthesis: the condensation of two isoprenoid diphosphates to form cyclopropylcarbinyl diphosphates, followed by ring opening. Here, we report the structures of Staphylococcus aureus dehydrosqualene synthase (CrtM) complexed with its reaction intermediate, presqualene diphosphate (PSPP), the dehydrosqualene (DHS) product, as well as a series of inhibitors. The results indicate that, on initial diphosphate loss, the primary carbocation so formed bends down into the interior of the protein to react with C2,3 double bond in the prenyl acceptor to form PSPP, with the lower two-thirds of both PSPP chains occupying essentially the same positions as found in the two farnesyl chains in the substrates. The second-half reaction is then initiated by the PSPP diphosphate returning back to the Mg(2+) cluster for ionization, with the resultant DHS so formed being trapped in a surface pocket. This mechanism is supported by the observation that cationic inhibitors (of interest as antiinfectives) bind with their positive charge located in the same region as the cyclopropyl carbinyl group; that S-thiolo-diphosphates only inhibit when in the allylic site; activity results on 11 mutants show that both DXXXD conserved domains are essential for PSPP ionization; and the observation that head-to-tail isoprenoid synthases as well as terpene cyclases have ionization and alkene-donor sites which spatially overlap those found in CrtM. 相似文献
73.
Hung-Wei Yeh Mei-Chi Chang Chun-Pin Lin Wan-Yu Tseng Hsiao-Hua Chang Tong-Mei Wang Yi-Jane Chen Chiu-Chun Lin Ting-Ting Yang Li-Deh Lin Jiiang-Huei Jeng 《Acta biomaterialia》2009,5(9):3404-3410
To compare the cytotoxicity of three nano-dentin bonding agents (nano-DBAs) and two non-nano-DBAs using Chinese hamster ovary (CHO-K1) cells. We found that nano fillers were not the major contributing factor in DBA cytotoxicity, as analyzed by colony forming assay and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Exposure of CHO-K1 cells to all three tested total-etching DBAs led to G0/G1 cell cycle arrest, whereas exposure to higher concentrations of two tested nano-DBAs induced G2/M arrest. All five DBAs further induced apoptosis at the highest concentration, as analyzed by propidium iodide staining flow cytometry. The toxicity of all DBAs (1:4000 v/v or higher) is related to increased reactive oxygen species (ROS) production, as analyzed by single cell DCF fluorescence flow cytometry. These results indicate that clinical application of DBAs may be potentially toxic to dental pulp tissues. Cytotoxicity of DBAs is associated with ROS production, cell cycle deregulation and apoptosis. Presence of methacrylate monomers such as PENTA and UDMA is possibly the major cytotoxic factor for DBAs. Further studies on other toxicological endpoints of nano-DBAs are necessary to highlight their safe use. 相似文献
74.
Leo Jeng Alexandra V Yamshchikov Suzanne E Judd Henry M Blumberg Gregory S Martin Thomas R Ziegler Vin Tangpricha 《Journal of translational medicine》2009,7(1):28
Background
Vitamin D insufficiency is common in hospitalized patients. Recent evidence suggests that vitamin D may enhance the innate immune response by induction of cathelicidin (LL-37), an endogenous antimicrobial peptide produced by macrophages and neutrophils. Thus, the relationship between vitamin D status and LL-37 production may be of importance for host immunity, but little data is available on this subject, especially in the setting of human sepsis syndrome and other critical illness. 相似文献75.
Chiu‐Chun Lin Mei‐Chi Chang Hsiao‐Hua Chang Tong‐Mei Wang Wan‐Yu Tseng Tseng‐Fang Tai Hung‐Wei Yeh Ting‐Ting Yang Liang‐Jiunn Hahn Jiiang‐Huei Jeng 《Environmental and molecular mutagenesis》2009,50(5):367-374
Epidemiological studies have shown a strong association between environmental exposure to betel quid (BQ) and oral cancer. Areca nut (AN), an ingredient of BQ, contains genotoxic and mutagenic compounds. In this study, we found that AN extract (ANE) inhibited the growth of Chinese hamster ovary cells (CHO‐K1) in a dose‐ and time‐dependent manner. Intracellular reactive oxygen species (ROS) levels and micronuclei (MN) frequency were significantly increased following ANE treatment in CHO‐K1 cells. Addition of catalase markedly inhibited ANE‐induced MN formation, indicating that ANE‐induced genotoxicity was correlated with intracellular H2O2. Incubation of CHO‐K1 cells with ANE (400–800 μg/ml) for 24 hr caused G2/M arrest, and prolonged exposure to ANE (800 μg/ml) significantly induced cell death. Surprisingly, ANE itself caused cytokinesis failure and subsequent increase in binucleated cell formation. Coexposure to catalase (2,000 U/ml) and ANE (800 μg/ml) reduced the generation of binucleated cells, indicating that ANE‐induced cytokinesis failure was associated with oxidative stress. Following prolonged exposure to ANE, an accumulation of hyperploid/aneuploid cells concomitant with bi‐, micro‐ or multinucleated cells was found. In summary, our results demonstrate that ANE exposure to CHO‐K1 cells caused increased MN frequency, G2/M arrest, cytokinesis failure, and an accumulation of hyperploid/aneuploid cells. These events are associated with an increase in intracellular H2O2 level and actin filament disorganization. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc. 相似文献
76.
Chao‐Chuan Chi Chorng‐Chih Huang Jau‐Min Chien Sau‐Tung Chu Wei‐Chuan Chen Hong‐Tai Chang Ko‐Long Lin Jeng‐Yu Tsai Wei‐Chuan Liao Chiang‐Ting Chou Chung‐Ren Jan 《Drug development research》2008,69(8):508-513
The effect of BayK 8644, a chemical widely used to activate L‐type Ca2+ channels, on cytosolic free Ca2+ concentrations ([Ca2+]i) in human oral cancer cells (OC2) has not been explored to date. The present study examined whether BayK 8644 altered basal [Ca2+]i levels in suspended OC2 cells by using fura‐2. BayK 8644 (10 pM–10 µM) increased [Ca2+]i in a concentration‐dependent manner. The Ca2+ signal was reduced partly by removing extracellular Ca2+. BayK 8644‐induced Ca2+ influx was blocked by nifedipine, but was not altered by the store‐operated Ca2+ entry inhibitors, econazole and SKF96365; protein kinase C modulators phorbol 12‐myristate 13‐acetate (PMA) and GF109203X; the protein kinase A inhibitor H89; and the phospholipase A2 inhibitor, aristolochic acid. In Ca2+‐free medium, after pretreatment with 1 µM BayK 8644, 1 µM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor)‐induced [Ca2+]i rises were abolished; and conversely, thapsigargin pretreatment abolished BayK 8644‐induced [Ca2+]i rises. Inhibition of phospholipase C with U73122 did not change BayK 8644‐induced [Ca2+]i rises. Collectively, in OC2 cells, BayK 8644 induced [Ca2+]i rises by causing phospholipase C‐independent Ca2+ release from the endoplasmic reticulum; and Ca2+ influx via L‐type Ca2+ channels. Drug Dev Res 69: 2008. © 2008 Wiley‐Liss, Inc. 相似文献
77.
J. F. Tsai J. E. Jeng M. S. Ho W. Y. Chang M. Y. Hsieh Z. Y. Lin J. H. Tsai 《British journal of cancer》1996,73(12):1498-1502
To assess the role of hepatitis B e antigen (HBeAg) and its interaction with hepatitis B surface antigen (HBsAg) on the development of hepatocellular carcinoma (HCC), this case-control study included 361 age- and sex-matched pairs of patients with histologically proven HCC and healthy control subjects. HBsAg, HBeAg and antibody to HBeAg (anti-HBe) were detected by radioimmunoassay. Antibodies to hepatitis C virus (anti-HCV) were detected by second-generation enzyme immunoassay. The prevalences of HBeAg (20.2%), HBsAg (80.3%) and anti-HCV (29.5%) in cases were higher than in controls (1.9%, 20.7%, and 2.7% respectively; each P < 0.0001). Using patients negative for HBsAg, HBeAg and anti-HBe as a referent group, univariate analysis indicated that HBsAg alone or HBsAg and HBeAg were risk factors for HCC (P for trend < 0.0001). Calculation of incremental odds ratio indicated that there was additive interaction between HBsAg and HBeAg. Multivariate analysis indicated that HCC development was strongly associated with the presence of HBeAg (odds ratio, 8.1; 95% confidence interval, 2.4-27.1), HBsAg (odds ratio, 68.4; 95% confidence interval, 20.5-227.8) and anti-HCV (odds ratio, 59.3; 95% confidence interval, 13.6-258.4). In conclusion, HBsAg, HBeAg and anti-HCV are independent risk factors for HCC. There is additive and independent effect modification between HBsAg and HBeAg on the development of HCC. 相似文献
78.
Pedunculated Hepatocellular Carcinoma: Clinicopathologic Study of 18 Surgically Resected Cases 总被引:9,自引:0,他引:9
We present the clinical features and outcomes of 18 surgically treated pedunculated hepatocellular carcinomas (P-HCCs). Hepatocellular
carcinoma is a notorious, hyperendemic disease in Taiwan. Pedunculated HCC, although not a novel finding, has been recognized
and diagnosed early by various imaging modalities. However, the clinicopathologic picture has not been fully clarified, and
the prognosis varies in each report. From 1986 to 1998 the clinical features of 18 surgically treated cases of P-HCC were
reviewed, including demographics, laboratory data, operative findings, pathologic features, and follow-up results. Factors
that may influence the outcomes were also analyzed. Clinical features and outcomes of 414 patients with nonpedunculated hepatocellular
(HCC) were summarized for comparison. Of 432 surgical resected hepatocellular carcinomas, 18 (4.2%) were P-HCCs. Larger tumor
size, more capsule formation, less vascular invasion, and wider resection margins were significantly prominent in the patients
in P-HCC group compared with those in the NP-HCC group. Multivariate stepwise logistic regression analysis revealed that the
P-HCC group had significantly larger tumors and wider resection margins. The 1-, 3-, and 5-year survival rates of P-HCC patients
were 88.3%, 77.4%, and 45.6%, respectively. A significant difference in survival was found between the P-HCC and NP-HCC groups.
P-HCC patients without vascular invasion might have a significantly better survival demonstrated by log-rank analysis stratified
by capsular invasion, vascular invasion, resection, and tumor size. We present the clinical features and outcomes of 18 surgically
treated pedunculated HCCs. Pedunculated HCCs might have a better survival than conventional HCCs after hepatic resection,
especially if there is no vascular invasion. 相似文献
79.
Loh SH Tsai CS Tsai Y Chen WH Hong GJ Wei J Cheng TH Lin CI 《European journal of pharmacology》2002,443(1-3):169-177
Accumulation of oxygen free radicals is an important mediator of post-ischemia/reperfusion cardiac dysfunction. However, oxidative injury has not been well characterized in human cardiac tissues. In the present study, we superfused hydrogen peroxide (H(2)O(2)) into the diseased human ventricle in order to assess the effects of oxygen free radicals on the electromechanical parameters and the intracellular pH (pH(i)), and to test the ability of certain potential cardioprotective agents, including scavengers of hydrogen peroxide (dibenzamidostilbene disulfonic acid; DBDS), the.OH free radical (N-(mercaptopropionyl)-glycine; N-MPG), and the HOCl free radical (L-methionine), to protect against oxidative injury. Disease human ventricular tissues were obtained from patients undergoing heart transplantation. Electrophysiological experiments were performed using a traditional micropipette, while the pH(i) was measured by microspectrofluorimetry. We found that (a) H(2)O(2) (30 microM-3 mM) induced a significant dose-dependent intracellular acidosis, (b) H(2)O(2) (30 microM-3 mM) had a notable dose-dependent biphasic effect on the contractile force (an increase, followed by a decrease), while moderate concentrations of H(2)O(2) also inhibited the generation of action potential and increased the diastolic resting force significantly, and (c) N-MPG caused significant block of both the intracellular acidosis and the electromechanical inhibition induced by 3 mM H(2)O(2), whereas L-methionine and DBDS did not. Our data suggest that the toxic effects of H(2)O(2) are caused mainly through the generation of.OH, which is attributed to the intracellular acidosis seen in the diseased human ventricle. 相似文献
80.
Spontaneous tumour rupture and prognosis in patients with hepatocellular carcinoma 总被引:17,自引:0,他引:17
BACKGROUND: Hepatocellular carcinoma (HCC) is a common disease in Taiwan. Ruptured HCC is an uncommon and potentially fatal complication of the condition. Information on the impact of ruptured HCC on hepatic resection is, however, limited. METHODS: The clinical features of 60 patients with ruptured HCC who underwent hepatic resection from 1986 to 1998 were reviewed. Clinical features and factors influencing the outcome of 475 patients with non-ruptured HCC were used for comparison. RESULTS: Of 535 surgically resected HCCs, 60 (11.2 per cent) were ruptured. Univariate analysis showed that sudden onset of abdominal pain, physical signs of haemodynamic unstability, reduced haemoglobin level and a raised aspartate aminotransferase level were more frequently found in patients with ruptured HCC than in those with non-ruptured tumours. Multivariate stepwise logistic regression analysis revealed sudden-onset abdominal pain to be the only independently significant factor in patients in the ruptured HCC group. The 1-, 3- and 5-year survival rates of patients with non-ruptured HCC were 72.1, 47.3 and 33.9 per cent, and those of patients with ruptured HCC were 54.2, 35.0 and 21.2 per cent respectively. Similar overall survival rates were found in patients with ruptured and non-ruptured HCC, although patients in the non-ruptured HCC group had a significantly better disease-free survival rate (P = 0.023). CONCLUSION: The presence of sudden-onset abdominal pain is the only independent indicator of ruptured HCC. Hepatic resection, when feasible, is the treatment of choice and can result in an overall survival rate comparable to that of patients with non-ruptured HCC. 相似文献