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Pooja Goswami Prasenjit Das Anil K. Verma Shyam Prakash T. K. Das T. C. Nag Vineet Ahuja Siddhartha Datta Gupta Govind K. Makharia 《Virchows Archiv : an international journal of pathology》2014,465(5):521-530
Abnormalities of transmembrane and cytoplasmic proteins of tight junctions (TJ) have been implicated in pathogenesis of both celiac (CeD) and Crohn’s diseases (CD). Since disease pathogenesis in CeD and CD are different, we planned to study if there is any differential expression pattern of TJ marker proteins and ultrastructural changes, respectively, in duodenal villi vs crypts. Endoscopic duodenal biopsies from treatment naïve patients with CeD (n?=?24), active CD (n?=?28), and functional dyspepsia (as controls, n?=?15), both at baseline and 6 months after treatment, were subjected to light microscopic analysis (modified Marsh grading); immune-histochemical staining and Western blot analysis to see the expression of key TJ proteins [trans-membrane proteins (claudin-2, claudin-3, claudin-4, occludin, and JAM) and cytoplasmic protein (ZO-1)]. Transmission electron microscopy and image analysis of the TJs were also performed. There was significant overexpression of claudin-2 (pore-forming) and occludin (protein maintaining cell polarity) with under-expression of claudin-3 and claudin-4 (pore-sealing proteins) in treatment naïve CeD and active CD with simultaneous alteration in ultrastructure of TJs such as loss of penta-laminar structure and TJ dilatation. Normalization of some of these TJ proteins was noted 6 months after treatment. These changes were not disease specific and were not different in duodenal villi and crypts. Overexpression of pore-forming and under-expression of pore-sealing TJ proteins lead to dilatation of TJ. These changes are neither disease specific nor site specific and the end result of mucosal inflammation. 相似文献
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Abhisheak Sharma Shyam H. Kamble Francisco Len Nelson J.‐Y. Chear Tamara I. King Erin C. Berthold Surash Ramanathan Christopher R. McCurdy Bonnie A. Avery 《Drug testing and analysis》2019,11(8):1162-1171
Kratom (Mitragyna speciosa) is a psychoactive plant popular in the United States for the self‐treatment of pain and opioid addiction. For standardization and quality control of raw and commercial kratom products, an ultra‐performance liquid chromatography?tandem mass spectrometry (UPLC?MS/MS) method was developed and validated for the quantification of ten key alkaloids, namely: corynantheidine, corynoxine, corynoxine B, 7‐hydroxymitragynine, isocorynantheidine, mitragynine, mitraphylline, paynantheine, speciociliatine, and speciogynine. Chromatographic separation of diastereomers, or alkaloids sharing same ion transitions, was achieved on an Acquity BEH C18 column with a gradient elution using a mobile phase containing acetonitrile and aqueous ammonium acetate buffer (10mM, pH 3.5). The developed method was linear over a concentration range of 1–200 ng/mL for each alkaloid. The total analysis time per sample was 22.5 minutes. The analytical method was validated for accuracy, precision, robustness, and stability. After successful validation, the method was applied for the quantification of kratom alkaloids in alkaloid‐rich fractions, ethanolic extracts, lyophilized teas, and commercial products. Mitragynine (0.7%–38.7% w/w), paynantheine (0.3%–12.8% w/w), speciociliatine (0.4%–12.3% w/w), and speciogynine (0.1%–5.3% w/w) were the major alkaloids in the analyzed kratom products/extracts. Minor kratom alkaloids (corynantheidine, corynoxine, corynoxine B, 7‐hydroxymitragynine, isocorynantheidine) were also quantified (0.01%–2.8% w/w) in the analyzed products; however mitraphylline was below the lower limit of quantification in all analyses. 相似文献
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Yamile Haito-Chavez Joanna K. Law Thomas Kratt Alberto Arezzo Mauro Verra Mario Morino Reem Z. Sharaiha Jan-Werner Poley Michel Kahaleh Christopher C. Thompson Michele B. Ryan Neel Choksi B. Joseph Elmunzer Sonia Gosain Eric M. Goldberg Rani J. Modayil Stavros N. Stavropoulos Drew B. Schembre Christopher J. DiMaio Vinay Chandrasekhara Muhammad K. Hasan Shyam Varadarajulu Robert Hawes Victoria Gomez Timothy A. Woodward Sergio Rubel-Cohen Fernando Fluxa Frank P. Vleggaar Venkata S. Akshintala Gottumukkala S. Raju Mouen A. Khashab 《Gastrointestinal endoscopy》2014
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Rupesh Raina Shyam Polaconda Nikhil Nair Ronith Chakraborty Sidharth Sethi Vinod Krishnappa Gaurav Kapur Maroun Mhanna Kirsten Kusumi 《Journal of clinical hypertension (Greenwich, Conn.)》2020,22(6):1059-1069
The morbidity and mortality of adult and pediatric chronic kidney disease (CKD) and end‐stage renal disease (ESRD) populations are mainly driven by cardiovascular disease (CVD). Improving CVD outcomes focuses on risk assessment of factors including diastolic blood pressure (DBP), systolic blood pressure (SBP), left ventricular mass index (LVMI), pulse pressure (PP), and pulse pressure index (PPi), which is calculated as PP/SBP. These markers are also proven predictors of CKD progression; however, their role in children has not been established. This study aims to evaluate the relationship between PP, PPi, ambulatory arterial stiffness index (AASI), and proteinuria with kidney function in pediatric CKD patients; it is a retrospective analysis of 620 patients (1‐16 years) from the NIDDK Chronic Kidney Disease in Children (CKiD) registry. The authors analyzed data for three separate cohorts: an overall CKD as well as immunological versus non‐immunological cause for CKD groups. An inverse relationship was found between SBP, DBP, and PP with iGFR and LVMI in the overall CKD group. Our immunological CKD subgroup showed significantly higher serum creatinine, SBP, DBP, and PP values with significantly lower serum albumin levels compared to the non‐immunological group. There were no significant differences with iohexol‐based glomerular filtration rate (iGFR), LVMI, PPi, or high‐sensitivity C‐reactive protein (hs‐CRP) between the two groups. A subgroup analysis demonstrated that SBP, DBP, and PP all correlated significantly with LVMI in the immunological CKD patients but not the non‐immunological subgroup. Additionally, AASI data in the overall CKD population were significantly correlated with PP, PPi, and DBP. This study is one of the first to correlate noninvasive measurements of vascular compliance including PP, PPi, and AASI with iGFR and LVMI in a pediatric CKD cohort. Improving our understanding of surrogate markers for early CVD is integral to improving the care of pediatric CKD population as these patients have yet to develop the hard end points of ESRD, heart failure, myocardial infarction, or stroke. 相似文献
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