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991.
Ja Kyung Kim Hye Young Chang Jung Min Lee Oidov Baatarkhuu Young Joon Yoon Jun Yong Park Do Young Kim Kwang‐Hyub Han Chae Yoon Chon Sang Hoon Ahn 《Journal of medical virology》2009,81(6):1002-1008
Recently, hepatitis B virus (HBV) genotypes and mutations have been reported to be related to hepatocellular carcinoma (HCC). This cross‐sectional case–control study examined the relationship between HCC and mutations in the enhancer II/core promoter and precore regions of HBV by comparing 135 Korean HCC patients infected with HBV genotype C2 (HBV/C2; HCC group) with 135 age‐, sex‐, and hepatitis B e antigen (HBeAg) status‐matched patients without HCC (non‐ HCC group). Age and sex were also matched between HBeAg‐positive and ‐negative patients. The prevalence of T1653, A1689, V1753, T1762/A1764, T1846, A1850, C1858, and A1896 mutations was evaluated in this population. The prevalence of the T1653 mutation in the box α region, the A1689 mutation in between the box α and β regions, and the T1762/A1764 mutations in the basal core promoter region was significantly higher in the HCC group compared to the non‐HCC group (8.9% vs. 2.2%, P = 0.017; 19.3% vs. 4.4%, P < 0.001; and 60.7% vs. 22.2%; P < 0.001). Among HBeAg‐negative patients, the frequency of the T1653 mutation was higher in the HCC group. Regardless of HBeAg status, the prevalence of the A1689, and T1762/A1764 mutations was higher in the HCC group than in the non‐HCC group. However, no association was observed between mutations in the precore region and HCC. Upon multivariate analysis, the presence of the T1653, A1689, and T1762/A1764 mutations was an independent predictive factor for HCC. The addition of the T1653 or A1689 mutation to T1762/A1764 increased the risk of HCC. In conclusion, the T1653, A1689, and/or T1762/A1764 mutations were associated with the development of HCC in Korean patients infected with HBV/C2. J. Med. Virol. 81:1002–1008, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
992.
Hepatitis B e antigen‐negative mutations in the precore and core promoter regions in Korean patients
Jong Won Choi Sang Hoon Ahn Jun Yong Park Hye Young Chang Ja Kyung Kim Oidov Baatarkhuu Do Young Kim Kwang‐Hyub Han Chae Yoon Chon 《Journal of medical virology》2009,81(4):594-601
Most patients with hepatitis B e antigen (HBeAg)‐negative chronic hepatitis B have variants of the hepatitis B virus (HBV) that include mutations in the precore or core promoter regions of the HBV genome. The aim of this study was to investigate the patterns of precore and core promoter mutations and their relationship to HBeAg expression in Korean patients. Four hundred seventy‐five Korean patients with chronic HBV infection between February 1995 and December 2003 were enrolled in this study. There were 236 HBeAg‐positive and 239 HBeAg‐negative patients. Blood samples were tested for HBsAg, anti‐HBs, HBeAg, hepatitis B e antibody (anti‐HBe), liver function tests, and serum HBV DNA. Mutations in the precore and core promoter regions were determined by direct sequencing. In the core promoter region, the C1740, C1753, T1762/A1764, and T1766 mutations were associated with HBeAg escape (all; P < 0.05). In the precore region, a higher frequency of the C1802, A1828, T1846, A1850, C1858, T1862, and A1896 mutations was found in HBeAg‐negative patients (all; P < 0.05). In particular, the A1896 mutation was associated with high serum levels of ALT and HBV DNA in HBeAg‐negative patients (P = 0.014 and 0.026, respectively). Mutations around the Kozak sequence (nucleotides 1809–1812) were found in 6.7% of patients and were not associated with undetectable HBeAg (P = 0.13). In Korean patients, various mutations in the precore and core promoter regions were associated with HBeAg escape and amelioration of hepatic inflammation in HBeAg‐ negative patients. Only the A1896 mutation contributed to HBeAg‐negative chronic hepatitis B. J. Med. Virol. 81:594–601, 2009 © 2009 Wiley‐Liss, Inc. 相似文献
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Hydrophilic electrospun polyurethane nanofiber matrices for hMSC culture in a microfluidic cell chip
Lee KH Kwon GH Shin SJ Baek JY Han DK Park Y Lee SH 《Journal of biomedical materials research. Part A》2009,90(2):619-628
Mimicking cellular microenvironments by MEMS technology is one of the emerging research areas. Integrated biomimetic systems with nanofiber polymer networks and microfluidic chips were fabricated and cellular behaviors were observed by changing surface characteristics of nanofibers and flow rates of microchannels. Modification of polyurethane nanofiber surfaces were achieved by grafting acrylic acid with plasma treatment and these nanofiber matrices were employed in a poly(dimethylsiloxane) based microfluidic chip. The surface characteristics of both electrospun nanofiber matrices was evaluated by measuring contact angle, porosity, and chemical structure using attenuated total reflection-Fourier transform infrared spectrometry. After modification, a terminal carboxyl group formed on the nanofiber surface and the wettability increased significantly. Human MSCs were seeded on the nanofiber matrices and a morphological investigation with actin filament staining and scanning electron microscopy was performed. A proliferation test by WST-1 and Live/Dead assay were performed to investigate the cell culture environment. It was observed that the cells on the AA-grafted nanofibers spread and proliferate compared to untreated nanofibers. It has also shown that flow rates in the microchannels played an important role for cell proliferation (Sim et al., Lab Chip 2007;7:1775-1782). Integration of nanofiber matrices into the microchannels provides the useful tools for mimicking cellular microenvironments and elucidating basic questions of cell and ECM assembly and interactions. 相似文献
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997.
Jung WH Gu BM Kang DH Park JY Yoo SY Choi CH Lee JM Kwon JS 《European archives of psychiatry and clinical neuroscience》2009,259(1):46-54
Objective
Although research has shown that deficits in various cognitive functions may underlie obsessive-compulsive disorder (OCD), studies have not yet clarified the specificity and etiology of perception processing, particularly the perception of biological motion that is correlated with social cognition. We used functional magnetic resonance imaging (fMRI) to investigate neural activity associated with the perception of biological motion in OCD patients. 相似文献998.
Chul‐Kee Park Sung‐Hye Park Se‐Hoon Lee Chae‐Yong Kim Dong‐Wan Kim Sun Ha Paek Dong Gyu Kim Dae Seog Heo Il Han Kim Hee‐Won Jung 《Neuropathology》2009,29(4):443-449
We analyzed the methylation status of the O6‐methylguanine‐DNA methyltransferase (MGMT) promoter using a methylation‐specific polymerase chain reaction (MSP) in glioblastoma patients treated with 1‐(4‐amino‐2‐methyl‐5‐pyrimidinyl)methyl‐3‐(2‐chloroethyl)‐3‐nitrosourea (ACNU) plus cisplatin followed by radiation therapy. Forty‐eight patients with interpretable MSP results were included in this study. The MGMT promoter was methylated in 26 patients (54.2%, methylated group) and unmethylated in 22 patients (45.8%, unmethylated group). Comparison of clinical outcomes between the two groups revealed that the methylation status of the MGMT gene promoter was not a prognostic factor for overall survival (P = 0.516) or a predictive factor for radiological response to ACNU plus cisplatin treatment (P = 0.529). The most noteworthy explanation for the result is that the synergistic antitumor effects of ACNU and cisplatin resulting from inactivation of MGMT by cisplatin in MGMT active tumors offset the drug resistance. 相似文献
999.
Choong Hyun Lee Jung Hoon Choi In Koo Hwang Ki-Yeon Yoo Hyung-Cheul Shin Moo-Ho Won 《中国神经再生研究》2009,(12):1078-1082
BACKGROUND: Thyroid hormones modulate proliferation of astrocytes and microglia depending on maturation stage and localization. Studies have demonstrated that triiodothyronine treatment or thyroidectomy during developmental stages results in morphological alterations and changes in the number of astrocytes and microglia. Little is known about the effects of hypothyroidism on astrocytes and microglia in adults. OBJECTIVE: To investigate the effects of hypothyroidism on morphology and number of astrocytes and microglia in the adult rat hippocampus. DESIGN, TIME AND SETTING: A randomized, controlled, neuroendocrinological, animal study was performed at the College of Medicine, Hallym University, South Korea between May 2008 and April 2009. MATERIALS: Methimazole, rabbit anti-glial fibrillary acidic protein (GFAP) antiserum, and rabbit anti-lba-1 antiserum were purchased from Sigma, USA. Rabbit anti-GFAP polyclonal antibody was provided by Chemicon, USA. Rabbit anti-lba-1 polyclonal antibody was purchased from Wako, Japan. Terminal deoxynucleotidyl transferase dUTP-biotin nick-end-labeling (TUNEL) kit was provided by Roche Molecular Biochemicals, Mannheim, Germany. METHODS: Hypothyroidism was induced in Wistar rats via methimazole administration (0.025%) in drinking water for 5 weeks, starting at 6 months of age. MAIN OUTCOME MEASURES: Following methimazole treatment, hippocampai neuronal death was determined using TUNEL staining. The morphology and number of GFAP and lba-1 immunoreactive cells were detected by immunohistochemistry. Hippocampal GFAP and lba-1 protein levels were detected by Western blot analysis. Serum-free triiodothyronine and thyroxine levels were quantified. RESULTS: TUNEL-positive neurons were not observed in the hippocampus of euthyroid and hypothyroid rats. Compared with the euthyroid rats, the number of GFAP immunoreactive astrocytes was decreased, and serum triiodothyronine and thyroxine levels were significantly decreased. In contrast, the number of lba-1 immunoreactive microglia was significantly increased in the hypothyroid rats (P 〈 0.05). In addition, GFAP immunoreactive astrocytes were morphologically at a resting state, and lba-1 immunoreactive microglia were morphologically hypertrophic. GFAP and IBa-1 protein changes in the hippocampus of euthyroid and hypothyroid rats were in accordance with immunohistochemical data. CONCLUSION: Although methimazole-induced hypothyroidism did not induce neuronal injury in the adult rat hippocampus, it did result in decreased astrocyte numbers and increased microglial hypertrophy. 相似文献
1000.
Beom SH Lee KW Yang Y Choi Y Song KH Kim YJ Kim JH Bang SM Chung JH Lee JS 《Japanese journal of clinical oncology》2011,41(11):1287-1291
We report the first case of adrenocortical carcinoma secreting cortisol (Cushing's syndrome) and aldosterone (Conn's syndrome) with extensive distant metastasis at the time of diagnosis. A 72-year-old male with exertional dyspnea sought evaluation at our institution. The pattern of tumor spread (lung, pleura, bone and adrenal gland) and respiratory symptoms secondary to the tumor led clinicians to diagnose the primary tumor site as lung cancer and the adrenal mass as a metastatic site. However, endocrinologic studies and a biopsy revealed the primary site to be adrenocortical carcinoma. After histopathologic confirmation, the patient was treated with palliative chemotherapy, including mitotane, cisplatin, etoposide and doxorubicin. The patient died on the 14th day after chemotherapy of rapidly progressive and unexpected pneumonia, which was thought to be an opportunistic infection secondary to Cushing's syndrome. Our case suggests that a thorough endocrinologic investigation is important in patients with an adrenal mass and clinicians should be aware that patients with adrenocortical carcinoma and Cushing's syndrome are susceptible to infections and need to be observed carefully for the possible development of unrecognized opportunistic infections. 相似文献