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91.
Majerović M Augustin G Jelincić Z Buković D Kekez T Matosević P Smud D Kinda E Golem AZ 《Collegium antropologicum》2008,32(3):703-707
Radiofrequency ablation (RFA) is one treatment modality for unresectable liver metastases. Patients with hepatic malignancies (n = 24) underwent elective RFA. All tumors were ablated with a curative intent, with a margin of 1 cm, in a single session of RFA. The median diameter of tumor was 3.1 cm (range 1.7-6.9 cm). Studied patients were not candidates for resection due to multifocal hepatic disease, extrahepatic disease, proximity to major vascular structures or presence of cirrhosis with functional hepatic reserve inadequate to tolerate major hepatic resection. Complete tumor necrosis was achieved in 87.5% and tumor recurred in 3 patients (12.5%) with lesions larger than 5 cm. Distant intrahepatic recurrence was diagnosed in another 4 (16.7%). Distant metastases were found in 7 (29.2%) patients. Four of these 7 patients had also distant intrahepatic recurrence of disease. Two and 5-years survival rates were 41.7% (10 patients) and 8.3% (2 patients) respectively. RFA is safe and effective option for patients with unresectable hepatic malignancies smaller than 5 cm without distant metastatic disease. RF ablation resulted in complete tumor necrosis in 87.5% with 2 and 5-years survival rates much higher than with chemotherapy alone or only supportive therapy, when survival is measured in weeks or months. If RFA is unavailable, percutaneous ethanol injection therapy can be done but with inferior survival rates. 相似文献
92.
Maria S. Johnson Terry T‐K. Huang Reinaldo Figueroa‐Colon James H. Dwyer Michael I. Goran 《Obesity (Silver Spring, Md.)》2001,9(10):593-598
Objective: The aim of this study was to determine whether initial levels or temporal changes in fasting leptin were associated with longitudinal changes in body‐fat mass in children. Research Methods and Procedures: The study group consisted of 85 children (42 white and 43 African American) with a mean initial age of 8.1 ± 0.1 years. The children had between three and six annual visits for repeated measurements of body composition by DXA and fasting leptin level. Fat mass and fasting leptin level were not normally distributed and were log‐transformed. Data were analyzed using SAS Proc mixed growth models, with log fat as the dependent variable. Results: Initial leptin level was a significant predictor of the change in fat mass over time (p < 0.0001), with high initial leptin levels resulting in increased fat gain, independent of initial fat levels. This relationship remained significant when the data were analyzed separately by race (whites, p < 0.0001; African Americans, p = 0.008). The relationship between the initial level of leptin and the change in fat mass was not modified by race, sex, or Tanner Stage. The rate of change in leptin during the study was significantly related to the rate of change in fat mass in African Americans (p = 0.008) but not in whites (p = 0.490). Discussion: In conclusion, high fasting leptin level at the start of the study was significantly associated with increasing fat mass in this cohort, indicating that the children may be developing resistance to the effects of leptin. 相似文献
93.
Terry T.‐K. Huang Maria S. Johnson Reinaldo Figueroa‐Colon James H. Dwyer Michael I. Goran 《Obesity (Silver Spring, Md.)》2001,9(5):283-289
Objective: To examine the patterns of growth of visceral fat, subcutaneous abdominal fat, and total body fat over a 3‐ to 5‐year period in white and African American children. Research Methods and Procedures: Children (mean age: 8.1 ± 1.6 years at baseline) were recruited from Birmingham, Alabama, and those with three or more repeated annual measurements were included in the analysis (N = 138 children and 601 observations). Abdominal adipose tissue (visceral and subcutaneous) was measured using computed tomography. Total body fat and lean tissue mass were measured by DXA. Random growth curve modeling was performed to estimate growth rates of the different body fat compartments. Results: Visceral fat and total body fat both exhibited significant growth effects before and after adjusting for subcutaneous abdominal fat and lean tissue mass, respectively, and for gender, race, and baseline age (5.2 ± 2.2 cm2/yr and 1.9 ± 0.8 kg/yr, respectively). After adjusting for total body fat, the growth of subcutaneous abdominal fat was not significant. Whites showed a higher visceral fat growth than did African Americans (difference: 1.9 ± 0.8 cm2/yr), but there was no ethnic difference for growth of subcutaneous abdominal fat or total body fat. There were no gender differences found for any of the growth rates. Discussion: Growth of visceral fat remained significant after adjusting for growth of subcutaneous abdominal fat, implying that the acquisition of the two abdominal fat compartments may involve different physiologic mechanisms. In contrast, growth of subcutaneous abdominal fat was explained by growth in total body fat, suggesting that subcutaneous fat may not be preferentially deposited in the abdominal area during this phase of growth. Finally, significantly higher growth of visceral fat in white compared with African American children is consistent with cross‐sectional findings. 相似文献
94.
95.
Houchun H. Hu Hee‐Won Kim Krishna S. Nayak Michael I. Goran 《Obesity (Silver Spring, Md.)》2010,18(4):841-847
The ability to accurately and noninvasively quantify fatty infiltration in organs such as the liver and the pancreas remains a critical component in understanding the link between obesity and its comorbidities such as type 2 diabetes and fatty liver disease. Single‐voxel (1H) proton magnetic resonance spectroscopy (MRS) has long been regarded as the gold‐standard noninvasive technique for such measurements. Recent advances in three‐dimensional fat–water magnetic resonance imaging (MRI) methods have led to the development of rapid, robust, and quantitative approaches that can accurately characterize the proportion of fat and water content in underlying tissues across the full imaging volume, and hence entire organs of interest. One such technique is called IDEAL (Iterative Decomposition with Echo Asymmetry and Least squares estimation). This article prospectively compares three‐dimensional (3D) IDEAL‐MRI and single‐voxel MRS in the assessment of hepatic (HFF) and pancreatic fat fraction (PFF) in 16 healthy subjects. MRS acquisitions took 3–4 min to complete whereas IDEAL acquisitions were completed in 20‐s breath‐holds. In the liver, there was a strong correlation (slope = 0.90, r2 = 0.95, P < 0.001) between IDEAL and MRS‐based fat fractions. In the pancreas, a poorer agreement between IDEAL and MRS was observed (slope = 0.32, r2 = 0.51, P < 0.02). The discrepancy of PFF is likely explained by MRS signal contamination from surrounding visceral fat, presumably during respiratory motion. We conclude that IDEAL is equally accurate in characterizing hepatic fat content as MRS, and is potentially better suited for fat quantification in smaller organs such as the pancreas. 相似文献
96.
Mirjana Lenhardt Goran Markovic Aleksandar Hegedis Stevan Maletin Miroslav Cirkovic Zoran Markovic 《Reviews in Fish Biology and Fisheries》2011,21(3):407-421
A total of 22 fish species have been introduced into the inland waters of Serbia, either intentionally or accidentally. This
paper provides a summary of data concerning time and reason of introduction, mode of expansion, degree of acclimatization,
impact on native fish and estimated area of recent distribution. Four of the non-native fish species currently occupy more
than 51% of Serbian territory while 5 of them occupy between 21–50% of territory. This paper reviews impacts of introduced
freshwater fish in Serbia based on collected data. 相似文献
97.
Development of interstitial cells of Cajal in the human digestive tract as the result of reciprocal induction of mesenchymal and neural crest cells 下载免费PDF全文
Goran Radenkovic Dina Radenkovic Aleksandra Velickov 《Journal of cellular and molecular medicine》2018,22(2):778-785
Neural crest cells (NCC) can migrate into different parts of the body and express their strong inductive potential. In addition, they are multipotent and are able to differentiate into various cell types with diverse functions. In the primitive gut, NCC induce differentiation of muscular structures and interstitial cells of Cajal (ICC), and they themselves differentiate into the elements of the enteric nervous system (ENS), neurons and glial cells. ICC develop by way of mesenchymal cell differentiation in the outer parts of the primitive gut wall around the myenteric plexus (MP) ganglia, with the exception of colon, where they appear simultaneously also at the submucosal border of the circular muscular layer around the submucosal plexus (SMP) ganglia. However, in a complex process of reciprocal induction of NCC and local mesenchyma, c‐kit positive precursors are the first to differentiate, representing probably the common precursors of ICC and smooth muscle cells (SMC). C‐kit positive precursors could represent a key impact factor regarding the final differentiation of NCC into neurons and glial cells with neurons subsequently excreting stem cell factor (SCF) and other signalling molecules. Under the impact of SCF, a portion of c‐kit positive precursors lying immediately around the ganglia differentiate into ICC, while the rest differentiate into SMC. 相似文献
98.
Sanja Mijatović Alessia Bramanti Ferdinando Nicoletti Paolo Fagone Goran N. Kaluđerović Danijela Maksimović-Ivanić 《Biotechnology advances》2018,36(6):1622-1632
Differentiation of cancer cells entails the reversion of phenotype from malignant to the original. The conversion to cell type characteristic for another tissue is named transdifferentiation. Differentiation/transdifferentiation of malignant cells in high grade tumor mass could serve as a nonaggressive approach that potentially limits tumor progression and augments chemosensitivity. While this therapeutic strategy is already being used for treatment of hematological cancers, its feasibility for solid malignancies is still debated. We will presently discuss the natural compounds that show these properties, with focus on anthraquinones from Aloe vera, Senna, Rheum sp. and hop derived prenylflavonoids. 相似文献
99.
100.
Stephen Henry Per-Ake Jovall Sohbat Ghardashkhani Anders Elmgren Tommy Martinsson Goran Larson Bo Samuelsson 《Glycoconjugate journal》1997,14(2):209-223
Total nonacid glycosphingolipids were isolated from small intestine mucosal scrapings of a red cell blood group O Le(a-b-)
nonsecretor cadaver. Glycolipids were extracted and fractionated into five fractions based on chromatographic and immunostaining
properties. These glycolipid fractions were then analysed by thin-layer chromatography for Lewis activity with antibodies
reactive to the type 1 precursor (Lec), H type 1 (Led), Lea and Leb epitopes. Fractions were structurally characterized by
mass spectrometry (EI-MS and EI-MS/MS-TOF) and proton NMR spectroscopy. EI-MS/MS-TOF allowed for the identification of trace
substances in fractions containing several other glycolipid species. Consistent with the red cell phenotype, large amounts
of lactotetraosylceramide (Lec-4) were detected. Inconsistent with the red cell phenotype, small quantities of Lea-5, H-5-1
and Leb-6 glycolipids were immunochemically and structurally identified in the small intestine of this individual. By EI-MS/MS-TOF
several large glycolipids with 9 and 10 sugar residues were also identified. The extensive carbohydrate chain elongation seen
in this individual with a Lewis negative nonsecretor phenotype supports the concept that Lewis and Secretor blood group fucosylation
may be a mechanism to control type 1 glycoconjugate chain extension. Abbreviations: FUT1, H gene; FUT2, Secretor gene, (gene
bank accession no. U17894); FUT3, Lewis gene or Fuc-TIII gene, (gene bank accession no. X53578); FUT5, Fuc-TV gene; [Imm]+,
immonium ion; Lea-5, Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Leb-6, Fucα1-2Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer;
Lec-4, Galβ1-3GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Led or H-5-1, Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Lex-5, Galβ1-4(Fucα1-3)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer;
MAb, monoclonal antibody; MS, mass spectrometry; CID, collision-induced dissociation; EI, electron impact ionisation; MS/MS-TOF,
tandem mass spectrometry using a time-of-flight mass spectrometer as the second mass spectrometer: m/Cz, mass-to-charge ratio;
NMR, nuclear magnetic resonance; PCR, polymerase chain reaction; RFLP, restriction fragment length polymorphism; TLC, (high
performance) thin layer chromatography. Saccharide types are abbreviated to Hex for hexose, HexNAc for N-acetylhexosamine
and dHex for deoxyhexose (fucose). Ceramide is abbreviated to Cer, and ceramide types are abbreviated to d for dihydroxy and
t for trihydroxy base, n for non-hydroxy and h for hydroxy fatty acids
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献