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991.
992.
Keiko Mitamura Chiharu Kawakami Hideaki Shimizu Takashi Abe Yasushi Konomi Yuki Yasumi Masahiko Yamazaki Masataka Ichikawa Norio Sugaya 《Journal of infection and chemotherapy》2013,19(4):633-638
We evaluated Clearline Influenza A/B/(H1N1)2009, a new multi-line immunochromatographic assay for rapid detection of antigens of influenza A (Flu A), B (Flu B), and A(H1N1)2009 viruses. Clearline detected Flu A, Flu B, and A(H1N1)2009 viruses with a detection limit of 4.6 × 103 to 7.5 × 104 pfu/assay. The sensitivity and specificity of detection of influenza virus by Clearline, using RT-PCR as reference standard, were determined for A(H1N1)2009, Flu A, and Flu B, in nasopharyngeal aspirate, nasopharyngeal swab, and self-blown nasal discharge specimens. Sensitivity for nasopharyngeal aspirate specimens was: A(H1N1)2009 = 97.3 %, Flu A = 94.5 %, and Flu B = 96.8 %, and specificity was Flu A = 99.1 % and Flu B = 100 %. Sensitivity for nasopharyngeal swab specimens was: A(H1N1)2009 = 91.9 %, Flu A = 92.8 %, and Flu B = 100 %, and specificity was Flu A = 98.2 % and Flu B = 100 %. Sensitivity for self-blown nasal discharge specimens was: A(H1N1)2009 = 75.7 %, Flu A = 86.5 %, and Flu B = 76.2 %, and specificity was Flu A = 98.4 % and Flu B = 100 %. Sensitivity and specificity of Clearline were sufficient for nasopharyngeal aspirate and swab specimens. For self-blown nasal discharge specimens, sensitivity was lower than for nasopharyngeal aspirates and nasopharyngeal swabs. The sensitivity of Clearline for A(H1N1)2009 was good even 6 h after the onset of symptoms. These findings suggest that Clearline may be useful for early clinical diagnosis of influenza. 相似文献
993.
Yamaguchi R Furusawa H Nakahara H Inomata M Namba K Tanaka M Ohkuma K Tayama K Fujii T Yano H Kage M Kojiro M 《Pathology international》2008,58(1):26-30
Invasive ductal carcinoma (IDC) with central acellular zone is sometimes encountered, but its clinicopathological features have not yet been fully investigated. The clinicopathological features of 10 resected cases of IDC with a large central acellular zone were investigated. The tumor size ranged from 6 to 28 mm with a mean of 14.3 +/- 6.9 mm. Contrast-enhanced magnetic resonance imaging (MRI) showed a ring-like appearance in the tumor. Sagittal fat-suppressed T2-weighted MRI had very high to intermediate signal intensity in a central area. Histologically, cancer tissue was located in the periphery of the tumor with a ring-like pattern and a large central area was occupied by acellular amorphous tissue that was strongly stained by alcian blue. Lymph vessel permeation was seen in eight cases. Among the tumors with focal enhancement in the central areas >1 cm in diameter on contrast MRI, marked increase of microvessel was observed in the enhanced spot. The mean of p53 and Ki-67 labeling indices was 56.2% and 36.3%, respectively. IDC with a large central acellular zone presenting with characteristic MRI should be noted as a new morphological entity. 相似文献
994.
Ito Y Ichikawa T Morohoshi Y Nakamura T Saegusa Y Ishihara K 《Biomedical research (Tokyo, Japan)》2008,29(1):27-32
Although it is known that tea catechins exert potent effects in obese subjects, there is scant information concerning these effects on body weight gain and body fat accumulation in the non-obese. We studied normal rats fed a normal diet and water containing either 0.1% or 0.5% tea catechins to examine the effects on body fat content and serum cholesterol levels, as well as evaluating whether the effect is related to bile acids, which in recent years have emerged as an inducer of energy expenditure. The administration of 0.5% catechins decreased the accumulation of body fat and the serum levels of cholesterol and bile acids. These results indicate that tea catechins modulate lipid metabolism not only in obese subjects, but also in the non-obese. 相似文献
995.
Pupil dilation and blinks provide complementary, mutually exclusive indices of information processing. Though each index is associated with cognitive load, the occurrence of a blink precludes the measurement of pupil diameter. These indices have generally been assessed in independent literatures. We examine the extent to which these measures are related on two cognitive tasks using a novel method that quantifies the proportion of trials on which blinks occur at each sample acquired during the trial. This measure allows cross-correlation of continuous pupil-dilation and blink waveforms. Results indicate that blinks occur during early sensory processing and following sustained information processing. Pupil dilation better reflects sustained information processing. Together these indices provide a rich picture of the time course of information processing, from early reactivity through sustained cognition, and after stimulus-related cognition ends. 相似文献
996.
997.
Iwatsuki K Ichikawa R Uematsu A Kitamura A Uneyama H Torii K 《Acta physiologica (Oxford, England)》2012,204(2):169-177
Information about nutrients is a critical part of food selection in living creatures. Each animal species has developed its own way to safely seek and obtain the foods necessary for them to survive and propagate. Necessarily, humans and other vertebrates have developed special chemosensory organs such as taste and olfactory organs. Much attention, recently, has been given to the gastrointestinal (GI) tract as another chemosensory organ. Although the GI tract had been considered to be solely for digestion and absorption of foods and nutrients, researchers have recently found taste-signalling elements, including receptors, in this tissue. Further studies have revealed that taste cells in the oral cavity and taste-like cells in the GI tract appear to share common characteristics. Major receptors to detect umami, sweet and bitter are found in the GI tract, and it is now proposed that taste-like cells reside in the GI tract to sense nutrients and help maintain homeostasis. In this review, we summarize recent findings of chemoreception especially through sweet and umami sensors in the GI tract. In addition, the possibility of purinergic transmission from taste-like cells in the GI tract to vagus nerves is discussed. 相似文献
998.
Joshita S Umemura T Katsuyama Y Ichikawa Y Kimura T Morita S Kamijo A Komatsu M Ichijo T Matsumoto A Yoshizawa K Kamijo N Ota M Tanaka E 《Human immunology》2012,73(3):298-300
IL28B single nucleotide polymorphisms (SNPs) are associated with spontaneous and treatment-induced elimination of hepatitis C virus (HCV). To assess whether the IL28B rs8099917 SNP also affects the progression of chronic HCV infection, we genotyped 511 Japanese HCV patients, including 69 with hepatocellular carcinoma (HCC). The T/T genotype of rs8099917 was not associated with the development of HCC (p = 0.623), although stepwise logistic regression analysis showed that liver cirrhosis, age greater than 68 years, and serum albumin <4.2 mg/dl were associated with HCC onset. It appears that the IL28B SNP does not directly influence hepatocarcinogenesis in chronic HCV infection. 相似文献
999.
Mougiakakos D Okita R Ando T Dürr C Gadiot J Ichikawa J Zeiser R Blank C Johansson CC Kiessling R 《Journal of molecular medicine (Berlin, Germany)》2012,90(8):935-944
Reactive oxygen species (ROS) are strongly implicated in melanoma development, and treatment with antioxidants has shown efficacy in suppressing malignant transition and progression. Here, we investigated the significance of the glutamate-L: -cysteine ligase catalytic subunit (GCLC) expression, a key regulator of glutathione synthesis, for malignant melanoma. A large set of melanoma cell lines (n?=?36) was analyzed, and higher GCLC levels were associated with lower presence of intracellular ROS and interestingly also lower rates of cell proliferation. Moreover, treatment with the antioxidant N-acetylcysteine efficiently reduced the growth speed of several investigated malignant cells. In addition GCLC expression was significantly linked to a prominent set of cellular antioxidants, accounting for the observed lower basal levels of oxidative stress and higher antioxidative capacity. Key attributes defining the malignant phenotype of melanoma cells including survival, invasiveness, and switch from E-cadherin to N-cadherin expression were more prominent in cells with lower GCLC expression. Our findings were further corroborated by observations in Rag2(-/-)γc(-/-)mice, in which melanoma cells with lower GCLC expression depicted a dramatically stronger tumor growth. Furthermore, prognostic significance of GCLC expression was investigated in patients (n?=?28) with advanced malignant melanoma. High tumor immunoreactivity for GCLC was a significant determinant for better 5-year overall survival. Conclusively, we show for the first time that GCLC may serve a dual role, as a surrogate marker for cellular redox state as well as malignant potential of melanoma cells. These promising results regarding its prognostic significance as well as its potential as a pharmacological target require further in-depth investigations. 相似文献
1000.
Sakamoto A Hayashi H Sakamoto I Isomoto I Eguchi S Takatsuki M Kanematsu T Abe K Hayashi T Uetani M 《Abdominal imaging》2012,37(2):239-243
The patient is a 20-year-old man with glycogen storage disease type I (GSD-type I). In his teens, multiple focal hepatic masses
were detected on abdominal ultrasonography (US), which were diagnosed as multiple hepatocellular adenomas from the imaging.
During follow-up, these masses had shown intermittent growth in size. In the evaluation of Gd-EOB-DTPA (gadolinium-ethoxybenzyl-diethylenetriamine
penta-acetic acid) MR imaging, these masses showed various signal intensities from hypo- to hyperintense during the hepatocyte-specific
phase. Intermittent growth and elevation of serum PIVKA-II levels indicate the potential for malignant transformation, so
the patient underwent partial hepatectomy. The resected masses were all consistent with benign hepatocellular adenomas histopathologically. 相似文献