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991.
Soyama A Eguchi S Takatsuki M Kawashita Y Hidaka M Tokai H Nagayoshi S Mochizuki S Matsumoto S Hamasaki K Tajima Y Kanematsu T 《Hepato-gastroenterology》2008,55(85):1390-1393
BACKGROUND/AIMS: E-cadherin (E-cad) is a type of adhesion molecule, and recent studies have demonstrated a correlation between its expression in tumor lesions and the recurrence of HCC. Serum levels of soluble E-cad are significantly elevated in patients with several types of cancer. The authors evaluated the significance of the serum level of soluble E-cad as a predictor of early recurrences (intrahepatic or extrahepatic metastasis) of HCC after a curative resection. METHODOLOGY: The concentrations of soluble E-cad in the serum of 25 HCC patients before surgery and 12 healthy subjects were measured using a sandwich enzyme-linked immunosorbent assay. The hepatic expression of E-cad was examined by immunohistochemical staining. RESULTS: The median serum soluble E-cad levels were significantly elevated in HCC patients before surgery in comparison to those in healthy subjects (10,759 ng/mL vs. 5,798 ng/mL, p < 0.05). The patients in the high serum soluble E-cad group experienced a higher incidence of early recurrence (p < 0.05). The levels of expression of E-cad in HCC lesions were not related to the serum levels of soluble E-cadherin. CONCLUSIONS: The study demonstrated that serum soluble E-cad levels were elevated in patients with HCC, and high serum soluble E-cadherin (> or = 8,000 ng/ml) was associated with early recurrence or extrahepatic metastasis. Serum soluble E-cad may therefore be a potential prognostic marker for HCC. 相似文献
992.
Yanagisawa N Takayama N Suganuma A 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2008,82(5):441-444
After severe exposure to suspected rabid animal, WHO recommends a complete vaccine series using a potent effective vaccine that meets WHO criteria, and administration of rabies immunoglobulin (RIG). RIG is not available globally, and is not marketed in Japan. If pre-exposure prophylaxis for rabies is given, RIG is unnecessary even after severe exposure. It is thus important to give pre-exposure prophylaxis for rabies to people who plan to go to rabies-endemic areas. In Japan, pre-exposure prophylaxis for rabies consists of 3 doses of cell-culture rabies vaccine. The first two doses are given 4 weeks apart, and the third dose is given 6-12 months after the first dose, all of which are injected subcutaneously (standard regimen). People who plan to travel abroad to rabies-endemic areas may know of their destinations only 1 or 2 months in advance at best. Therefore, it is virtually impossible to complete the 3 dose regimen for rabies in Japan. Pre-exposure prophylaxis recommended by WHO consists of 3 doses given intramuscularly on days 0, 7, and 28, making it possible to complete pre-exposure prophylaxis in one month. This WHO recommended pre-exposure prophylaxis using Japanese cell-cultured rabies vaccine (PCEC-K) has not been studied, so we elected to fill the gap using PCEC-K, administered based on the WHO recommendation and examined its efficacy and safety. Subjects were 26 healthy volunteers with no previous rabies vaccination giving oral and written consent. Vaccine was administered on days 0, 7, and 28, and rabies antibody levels were tested on days 7, 28, and 42. On day 7, every antibody level was negative. On day 28, antibody levels were between 0.7-3.5 EU/ mL, with the exception of 3 cases still negative. On day 42, all cases, including the 3 negative cases, exceeded 1.6 EU/mL, providing sufficient protection against rabies. This result was not inferior compared to the standard regimen. Local adverse effects such as erythema and pain were noted, but none were serious. In conclusion, WHO recommended pre-exposure prophylaxis for rabies using PCEC-K is considered effective and safe. 相似文献
993.
Yonezawa A Yoshizumi M Ebiko M Ise SN Watanabe C Mizoguchi H Kimura Y Sakurada S 《Pharmacology, biochemistry, and behavior》2008,88(4):367-373
It has been reported that systemic administration of m-CPP (1-[3-chlorophenyl] piperazine hydrochloride), a 5-HT(2) receptor agonist, produces a 5-HT(2C) receptor-mediated penile erections and self-grooming in rats. In the present study, we examined the ability of m-CPP to induce ejaculation in rats and determined which 5-HT(2) receptor subtypes may be involved in the m-CPP-induced ejaculation. The ejaculatory response was assessed by weighing the seminal materials accumulated over 30 min. In Experiment 1, systemic administration of m-CPP (0.1-3.0 mg/kg, i.p.) produced a dose-dependent increase in both the incidence of ejaculation and the weight of the seminal materials. The inverted U-shaped dose-response effects of m-CPP on penile erection and genital grooming were also observed, with maximum effects at 0.6 mg/kg. Pretreatment with SB242084 (0.1 and 0.3 mg/kg, i.p.), a selective 5-HT(2C) receptor antagonist, dose-dependently attenuated the ejaculatory response induced by m-CPP (3.0 mg/kg). The proejaculatory effect of m-CPP was also attenuated by ketanserin (0.3 and 1.0 mg/kg, i.p.), a 5-HT(2A) receptor antagonist, whereas SB204741 (0.1 and 0.3 mg/kg, i.p.), a selective 5-HT(2B) receptor antagonist, significantly potentiated the m-CPP-induced ejaculatory response. Penile erection and genital grooming induced by m-CPP (0.3 mg/kg, i.p.) was only blocked by SB242084. In Experiment 2 (termed as corset test), in rats fitted with a corset at the thoracic level to prevent the loss of seminal materials by genital grooming, the proejaculatory effect of m-CPP was more efficiently detected than in the non-fitted animals: the ED(50) value for inducing ejaculation was reduced to less than 50% of the ED(50) in non-fitted animals. In this test, the proejaculatory effect of m-CPP (0.6 mg/kg, i.p.) was completely blocked by SB242084 (0.3 mg/kg, i.p.), whereas ketanserin (0.3 mg/kg, i.p.) or SB204741 (0.3 mg/kg, i.p.) did not affect the m-CPP -induced ejaculation. From these observations, it is suggested that the 5-HT(2) receptor agonist m-CPP at low doses (0.3-1.0 mg/kg) possesses the proejaculatory as well as proerectile effects in rats that are primarily associated with the activation of 5-HT(2C) receptors, and that the activation of 5-HT2B receptors may produce an inhibitory effect on ejaculation induced by a high dose (3.0 mg/kg) of m-CPP. Furthermore, the results of the present study also indicate that the corset test employed in this study may be useful for detecting the proejaculatory effect of the compounds. 相似文献
994.
The present review paper summarizes the data available in the literature concerning dinitrophenolic compounds and evaluates male reproductive toxicity in experimental animals. Gavage and feeding doses of 2-sec-butyl-4,6-dinitrophenol (dinoseb; CAS No. 88-85-7) manifested testicular toxicity, and 4,6-dinitro-o-cresol (DNOC; CAS No. 534-52-1) showed similar but weaker testicular toxicity in laboratory animals. Consecutive doses of dinoseb and DNOC by gavage seemed to induce spermatotoxicity by disturbing spermiogenesis or the maturation process of sperm in the epididymis, and the most probable target cells of spermatotoxicity were thought to be testicular spermatids in rats. Prolonged exposure to dinoseb and DNOC in the diet also induced testicular toxicity in rats. However, the feeding dose of dinoseb irreversibly affected the early stage of spermatogenesis and produced infertility in rats. On the other hand, 2,4-dinitrophenol (DNP; CAS No. 51-28-5) did not show testicular toxicity in laboratory animals according to available literature. Further studies in laboratory animals with nitrophenolic compounds are required for clarification of their testicular toxicity and for risk assessment in humans. 相似文献
995.
Hirata-Koizumi M Noda A Hirose A Kamata E Ema M 《Reproductive toxicology (Elmsford, N.Y.)》2008,25(2):231-238
Twelve male and female rats per group were given tetrahydrofurfuryl alcohol (THFA) by gavage at 0, 15, 50, 150 or 500 mg/kg/day. Males were dosed for 47 days, beginning 14 days before mating, and females were dosed for 42–52 days beginning 14 days before mating to day 4 of lactation throughout the mating and gestation period. Changes in locomotor activity, inhibition of body weight gain, and/or histopathological changes in the thymus, spleen, testes and/or epididymides were observed in males and females at 150 mg/kg and above. No effects of THFA were found on the copulation index, fertility index, or the number of corpora lutea and implantations in pregnant females. At 500 mg/kg, no pregnant females delivered any pups. At 150 mg/kg, gestation length was prolonged, and the total number of pups born and the number of live pups on postnatal days 0 and 4 was markedly decreased. No effects of THFA were found on the sex ratio and body weight of live pups, or the incidence of pups with malformations or variations. Based on these findings, the NOAELs for parental and reproductive/developmental toxicity of THFA were concluded to be 50 mg/kg/day in rats. 相似文献
996.
Nemoto T Kanai T Yanagita T Satoh S Maruta T Yoshikawa N Kobayashi H Wada A 《European journal of pharmacology》2008,586(1-3):82-89
In cultured bovine adrenal chromaffin cells, where Akt1 is the predominant isoform over Akt2 and Akt3, chronic (> or =12 h) treatment with 1-20 mM LiCl, an inhibitor of glycogen synthase kinase-3, decreased Akt1 level by approximately 52% (EC50=3.7 mM; t1/2=l2 h); it was associated with LiCl-induced increased levels of Ser9-phosphorylated glycogen synthase kinase-3beta (approximately 37%) and beta-catenin (approximately 59%), two hallmarks of glycogen synthase kinase-3beta inhibition. The same LiCl treatment did not change phosphoinositide 3-kinase, phosphoinositide-dependent kinase 1, and extracellular signal-regulated kinase-1/2 levels. Treatment with SB216763 [3-(2,4-dichlorophenyl)-4-(1-methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione], a selective inhibitor of glycogen synthase kinase-3, lowered Akt1 level by approximately 67% (EC50=2 microM; t1/2=l2 h), when SB216763 caused concentration- and time-dependent increase of beta-catenin level by approximately 76%. LiCl- or SB216763-induced Akt1 decrease, as well as increases of Ser9-phosphorylated glycogen synthase kinase-3beta and beta-catenin were restored to the control levels of nontreated cells after the washout of LiCl (20 mM for 24 h)- or SB216763 (30 microM for 24 h)-treated cells. LiCl-induced Akt1 reduction was not prevented by beta-lactone, lactacystin (two inhibitors of proteasome), calpastatin (an inhibitor of calpain), or leupeptin (an inhibitor of lysosome). LiCl decreased Akt1 mRNA level by 20% at 6 h, with no effect on Akt1 mRNA stability. These results suggest that glycogen synthase kinase-3beta inhibition caused down-regulation of Akt1 mRNA and Akt1 protein levels; conversely, constitutive activity of glycogen synthase kinase-3beta maintains steady-state level of Akt1 in quiescent adrenal chromaffin cells. 相似文献
997.
Kobayashi M Nakahara K Seki T Miki S Kawauchi S Suyama A Wakasa-Morimoto C Kodama M Endoh T Oosugi E Matsushita Y Murai H Fujishita T Yoshinaga T Garvey E Foster S Underwood M Johns B Sato A Fujiwara T 《Antiviral research》2008,80(2):213-222
Resistance passage studies were conducted with five INIs (integrase inhibitors) that have been tested in clinical trials to date: a new naphthyridinone-type INI S/GSK-364735, raltegravir, elvitegravir, L-870,810 and S-1360. In establishing the passage system and starting from concentrations several fold above the EC(50) value, resistance mutations against S-1360 and related diketoacid-type compounds could be isolated from infected MT-2 cell cultures from day 14 to 28. Q148R and F121Y were the two main pathways of resistance to S/GSK-364735. Q148R/K and N155H, which were found in patients failing raltegravir treatment in Phase IIb studies, were observed during passage with raltegravir with this method. The fold resistance of 40 mutant molecular clones versus wild type virus was compared with these five INIs. The overall resistance pattern of S/GSK-364735 was similar to that of raltegravir and other INIs. However, different fold resistances of particular mutations were noted among different INIs, reflecting a potential to develop INIs with distinctly different resistant profiles. 相似文献
998.
Oka T Tooi O Mitsui N Miyahara M Ohnishi Y Takase M Kashiwagi A Shinkai T Santo N Iguchi T 《Aquatic toxicology (Amsterdam, Netherlands)》2008,87(4):215-226
There is a growing international concern that commonly used environmental contaminants have the potential to disrupt the development and functioning of the reproductive system in amphibians. One such chemical of interests is the herbicide atrazine. Effects of atrazine on sex differentiation were studied using wild-type Xenopus laevis tadpoles and all-ZZ male cohorts of X. laevis tadpoles, produced by mating wild-type ZZ male to sex-reversed ZZ male (female phenotype). Stage 49 tadpoles were exposed to 0.1-100 ppb atrazine or 0.27 ppb (1 nM) 17beta-estradiol (E(2)) until all larvae completed metamorphosis (stage 66). Metamorphosis, gonadal morphology and histology, CYP19 (P450 aromatase) mRNA induction, and hepatic vitellogenin (VTG) induction were investigated. Effects of atrazine on VTG-induction were also assessed in vitro in primary-cultured X. laevis hepatocytes. Atrazine had no effect on metamorphosis of developing wild-type or all-male X. laevis larvae. Statistical increase in female ratios was observed in 10 and 100 ppb atrazine groups in comparison with control group. While no hermaphroditic froglet was observed in all atrazine groups. In ZZ males, sex reversal was induced by 0.27 ppb E(2), but not by atrazine at concentrations of 0.1 and 1.0 ppb. In addition, neither P450 aromatase mRNA in the gonad nor hepatic VTG were induced by atrazine. Furthermore, VTG was not induced by 1000 ppb atrazine in primary-cultured hepatocytes. Our results indicate that female ratios in developing X. laevis tadpoles were increased by 10 and 100 ppb atrazine under the present experimental conditions. While the other endpoints showed no effect in the range of 0.1-100 ppb atrazine. These results suggest that effect of atrazine on sexual differentiation was not caused by estrogenic action and has no induction ability of P450 aromatase gene in gonad. 相似文献
999.
Considerable advances have been made in the research and development of oligonucleotide therapeutics (OTs) for treating central nervous system (CNS) diseases, such as psychiatric and neurodegenerative disorders, because of their promising mode of action. However, due to the tight barrier function and complex physiological structure of the CNS, the efficient delivery of OTs to target the brain has been a major challenge, and intensive efforts have been made to overcome this limitation. In this review, we summarize the representative methodologies and current knowledge of biodistribution, along with the pharmacokinetic/pharmacodynamic (PK/PD) relationship of OTs in the CNS, which are critical elements for the successful development of OTs for CNS diseases. First, quantitative bioanalysis methods and imaging-based approaches for the evaluation of OT biodistribution are summarized. Next, information available on the biodistribution profile, distribution pathways, quantitative PK/PD modeling, and simulation of OTs following intrathecal or intracerebroventricular administration are reviewed. Finally, the latest knowledge on the drug delivery systems to the brain via intranasal or systemic administration as noninvasive routes for improved patient quality of life is reviewed. The aim of this review is to enrich research on the successful development of OTs by clarifying OT distribution profiles and pathways to the target brain regions or cells, and by identifying points that need further investigation for a mechanistic approach to generate efficient OTs. 相似文献
1000.
Tsutomu Tamada Katsuyoshi Ito Naoki Kanomata Teruki Sone Akihiko Kanki Atsushi Higaki Minoru Hayashida Akira Yamamoto 《European radiology》2016,26(3):646-655