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991.
Two reaction conditions were developed to accomplish the substrate switchable Suzuki–Miyaura coupling of benzyl derivatives and arylboronic acid derivatives. Under conditions for esters, benzyl esters such as carbonates and acetates reacted with arylboronic acids to afford the corresponding diarylmethanes. However, the benzyl halides did not react under the same conditions. On the other hand, benzyl halides such as bromides and chlorides furnished diarylmethanes under conditions for halides, under which benzyl ester substrates did not react, in which water was found to play an important role. This switching system was tested using the intermolecular/intramolecular competitive reactions, during which the desired products could be synthesized by selecting the appropriate reaction conditions.Two reaction conditions were developed to accomplish the substrate switchable (benzyl esters vs. benzyl halides) Suzuki–Miyaura coupling. 相似文献
992.
Early evaluation of response to sorafenib for hepatocellular carcinoma by duplex Doppler ultrasonography
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993.
Quite a few epidemiological studies including meta‐analyses indicate that prostate inflammation is associated with increased risk of prostate cancer. The cause of inflammation in the prostate is speculated to be several microorganisms that cause prostatitis or sexually transmitted infections. Other specific microorganisms, such as xenotropic murine leukemia virus‐related virus, are also reported to relate to the development of prostate cancer; however, the contribution of this microorganism to prostate cancer development needs to be carefully interpreted. Environmental factors, especially dietary factors, might also be associated with prostate cancer development. Among related dietary factors, charred meat carcinogen 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine might be a link between environmental factors and inflammation, because 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine has the potential to accelerate prostate inflammation through its estrogenic effect. In light of these findings, preventing or reducing prostate inflammation might be one strategy for chemoprevention of prostate cancer. 相似文献
994.
Takeya Kitta Vikas Tyagi Masato Nanri Mamoru Kiniwa Katsuya Nonomura Naoki Yoshimura 《International urogynecology journal》2013,24(4):683-688
Introduction and hypothesis
Anticholinergics are used to treat overactive bladder. Anticholinergic agents such as propiverine hydrochloride reportedly increase plasma catecholamine levels in rats. It is also known that active urethral closure mechanisms prevents stress urinary incontinence (SUI), which is enhanced by central and peripheral noradrenergic system activation. Therefore, we examined the influence of propiverine hydrochloride on urethral anti-incontinence function in rats.Methods
Adult female rats were divided into propiverine and vehicle-treated groups. The propiverine group was given propiverine orally once a day for 2 weeks, after which urethral function and plasma concentrations of catecholamine (dopamine, norepinephrine, epinephrine) were tested.Results
Urethral baseline pressure measured by a microtransducer-tipped urethral catheter and leak-point pressure during passive intravesical pressure elevation were significantly increased in the propiverine group compared with the vehicle group. Plasma norepinephrine and epinephrine levels in the propiverine group were also significantly increased.Conclusions
Propiverine treatment that increases plasma catecholamine levels could contribute to improvement of SUI conditions by increasing urethral resistance. 相似文献995.
Kosuke Akiyama Noritaka Ohga Nako Maishi Yasuhiro Hida Kazuko Kitayama Taisuke Kawamoto Takahiro Osawa Yuko Suzuki Nobuo Shinohara Katsuya Nonomura Masanobu Shindoh Kyoko Hida 《Pathology international》2013,63(1):37-44
Tumor angiogenesis is necessary for tumor progression and metastasis; therefore, tumor blood vessels are potential therapeutic targets in anticancer therapy. We previously reported that tumor endothelial cells (TECs) exhibit different phenotypes compared with normal endothelial cells (NECs), and microarray analyses of mouse TECs and NECs have shown that several genes are upregulated in TECs compared with NECs. Among these genes, the expression levels of prostaglandin F receptor (PTGFR) mRNA, which encodes the prostaglandin F receptor (FP), were higher in TECs than in NECs. It has been reported that FP and its ligand, prostaglandin F2α, are involved in tumor angiogenesis. However, there have been no reports of the expression of PTGFR in the tumor vessels of renal cell carcinoma (RCC). Thus, we isolated human TECs (hTECs) from RCCs. The expression levels of PTGFR mRNA were also upregulated in hTECs. In addition, immunostaining showed that the PTGFR was expressed in human tumor blood vessels in vivo. These findings suggested that PTGFR is a novel TEC marker and that it may be a novel target for antiangiogenic therapy for RCC. 相似文献
996.
Hidaka H Nakazawa T Wang G Kokubu S Minamino T Takada J Tanaka Y Okuwaki Y Watanabe M Tanabe S Shibuya A Koizumi W 《Journal of gastroenterology》2012,47(2):118-126
Background and purpose
Elective esophageal variceal ligation (EVL) is performed to decrease the risk of variceal hemorrhage. EVL is associated with adverse effects, including post-ligated bleeding, chest pain, and dysphagia. Proton pump inhibitors (PPIs) are the most potent pharmacological agents for inhibition of gastric acid secretion. However, the long-term effect of PPIs after EVL remains unclear. The aim of this study was to assess the efficacy of rabeprazole, a PPI, after variceal eradication by EVL.Methods
We performed a randomized, controlled trial in Kitasato University East Hospital. The primary endpoint was treatment failure, defined as variceal hemorrhage or severe medical complications. Between July 2007 and September 2010, 43 patients were randomized into this study and followed up until September 2010.Results
Twenty-one patients in the rabeprazole arm received 10?mg rabeprazole daily after EVL, and 22 patients in the control received no antisecretory treatment from the same stage. Baseline characteristics did not differ between the groups (median Child-Pugh score, 6; median age, 62?years; median follow-up, 18.7?months). The trial was stopped early after an interim analysis showed that the risk of bleeding and failure of rabeprazole treatment was lower than that of no antisecretory treatment with the log-rank test showing a significant difference between the groups (P?=?0.007) and a hazard ratio of 0.098 [95% confidence interval, 0.012?C0.79 (P?=?0.029)].Conclusions
Long-term administration of PPIs reduced the risk of treatment failure after EVL. Acid suppression therapy should also be considered as a treatment option after EVL. 相似文献997.
Hidaka H Nakazawa T Kaneko T Minamino T Takada J Tanaka Y Okuwaki Y Watanabe M Shibuya A Koizumi W 《Journal of gastroenterology》2012,47(9):1030-1035
Background and aims
Sorafenib is currently in clinical use as an oral multikinase inhibitor that blocks tumor growth and cell proliferation in advanced hepatocellular carcinoma (HCC). It has been demonstrated in a translating study that sorafenib had a beneficial effect on portocollateral circulation in cirrhotic animals with portal hypertension. This study was prospectively performed to evaluate the portal hemodynamic effect of sorafenib in patients with advanced HCC using duplex Doppler ultrasonography (DDU).Methods
Twenty-five Child-Pugh class-A patients with advanced HCC had received sorafenib at a dose of 400?mg twice daily. Primary outcomes were changes in portal venous area (PVA; cm2) as seen by using DDU before and after a 2-week administration of sorafenib. Secondary outcomes included the changes of laboratory data and other flow data revealed on DDU.Results
PVA was significantly decreased after a 2-week administration (0.78?±?0.23 vs. 0.64?±?0.25, P?=?0.023), while the portal venous flow velocity (PVV; cm/s) was not significantly changed (0.22?±?0.06 vs. 0.24?±?0.07, P?=?0.17). Therefore, the congestion index (PVA/PVV), which reflects the pathophysiological hemodynamics of portal venous system, was significantly decreased (3.9?±?1.7 vs. 3.0?±?1.4, P?=?0.042).Conclusions
We demonstrated the portal hemodynamic effect of sorafenib in patients with advanced HCC. Considering that this was a short-term study, because sorafenib could be a potential beneficial therapeutic agent for portal hypertension, it will be necessary to verify its clinical benefits for portal hypertension in future studies. 相似文献998.
999.
Shigeru Adachi Akitaka Shibuya Yukiko Miura Atsuko Takeuchi Takahide Nakazawa Katsunori Saigenji 《Scandinavian journal of gastroenterology》2013,48(7):849-856
Objective. Although hepatitis B virus (HBV) DNA can be detected in liver or sera of patients without serum hepatitis B surface antigen (HBsAg), its clinical relevance in hepatocarcinogenesis remains controversial. This observational cohort study was conducted to clarify the risk factors, including the presence of serum HBV DNA and hepatitis B core antibody (anti-HBc), for hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). Material and methods. The study comprised 123 patients with LC due to HCV, and negative for HBsAg. The risk factors for HCC development were analyzed by univariate and multivariate analysis. Serum samples were assayed for HBV DNA using real-time polymerase chain reaction. Results. Serum HBV DNA was detectable in 14 patients (11.4%) and serum anti-HBc in 96 (78.0%). During the follow-up period (mean 53.3 months), 80 patients (65.0%) developed HCC. The cumulative HCC development rate was significantly higher in the anti-HBc-positive group than in the anti-HBc-negative group (p=0.0039), but did not differ between the serum HBV DNA-positive and -negative groups (p=0.8570). The multivariate analysis indicated that male gender, alpha-fetoprotein (AFP) 20 ng/ml or greater, average serum alanine aminotransferase (ALAT) 80 IU/l or greater and the presence of anti-HBc were independent risk factors for development of HCC (p=0.038, p=0.013, p=0.020 and p=0.001, respectively). Conclusions. Serum anti-HBc, which indicates a previous HBV infection, has clinical significance in hepatocarcinogenesis in patients with HCV-related LC, but serum HBV DNA does not. Therefore, anti-HBc in serum is a significant predictor for HCC. 相似文献
1000.
Yasuo Yoshioka Koji Konishi Osamu Suzuki Yasutomo Nakai Fumiaki Isohashi Yuji Seo Yuki Otani Masahiko Koizumi Ken Yoshida Hideya Yamazaki Norio Nonomura Kazuhiko Ogawa 《Radiotherapy and oncology》2014