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991.
992.
Michael C. Honigberg Amy A. Sarma 《Current treatment options in cardiovascular medicine》2018,20(7):54
Purpose of review
To educate clinicians on cardiovascular considerations and management strategies surrounding pregnancy in childhood cancer survivors.Recent findings
With advances in oncologic treatment, growing numbers of childhood cancer survivors are now able to consider pregnancy. A significant proportion of survivors have received cardiotoxic therapy, particularly anthracyclines, and/or chest radiation. Cardiomyopathy is the most common cardiac complication of cancer-directed therapy; pericardial disease, valvular disease, premature coronary artery disease, and conduction abnormalities are other potential sequelae. In female survivors of childhood malignancy, cardiac evaluation should be performed prior to pregnancy as subclinical disease has the potential to be unmasked by the hemodynamic stress of pregnancy. However, limited data exist on pregnancy outcomes after cancer survivorship.Summary
With appropriate management, maternal and fetal outcomes in pregnancy following childhood cancer are generally favorable. Further research is needed to understand the incidence of cardiac complications among childhood cancer survivors, strategies to prevent these complications, optimal cardiovascular management during pregnancy and the postpartum period, and on the impact of pregnancy itself on the natural history of treatment-related cardiotoxicity.993.
Pluripotent hematopoietic progenitor cells (CFU-GEMM), myeloid progenitor cells (CFU-GM), and erythroid progenitors (BFU-E) were studied in midtrimester human fetuses using the mixed colony assay. All three progenitor cell populations were detected at high levels in the fetal liver from 12 to 23 wk of gestation. Stem cells were first observed in the bone marrow at 15-16 wk of gestation, although bone marrow cultures from earlier fetuses showed heavy growths of stromal cells. Spleen cultures first showed growth of stem cells at 18-19 wk, but fetal thymus showed no hematopoietic activity. Peripheral blood from four fetuses aged 13, 18, 20, and 21 wk showed very high levels of all 3 progenitor cells. The results demonstrate that hematopoietic development in the human fetus parallels that of the mouse. The observation that stromal cell development in the bone marrow precedes the appearance of hematopoietic progenitor cells suggests that they may be closely involved in stem cell growth. 相似文献
994.
Adrenocortical function in patients with pulmonary tuberculosis 总被引:1,自引:0,他引:1
G R Sarma C Immanuel G Ramachandran P V Krishnamurthy V Kumaraswami R Prabhakar 《Tubercle》1990,71(4):277-282
Adrenocortical function was studied in patients with pulmonary tuberculosis and the findings compared with those in healthy subjects. Plasma cortisol levels in newly diagnosed patients were appreciably higher than in the healthy subjects (P less than 0.001). A normal (positive) response to ACTH (tetracosactrin) stimulation was observed in 35 (97%) of 36 healthy subjects, 15 (56%) of 27 newly diagnosed patients with tuberculosis and 5 (42%) of 12 chronic cases (i.e. those who had had the disease for more than 3 years); the difference between the healthy subjects and the two groups of tuberculosis patients was highly significant (P less than 0.001). Dexamethasone caused an appreciable decrease in the plasma cortisol levels of tuberculosis patients. Considering the diurnal variation of cortisol secretion, there was a steady decline in the cortisol levels between 08:00 and 20:00 in the healthy subjects (P = 0.02); in the tuberculosis patients, however, there was a decrease up to 16:00 followed by a significant increase (P = 0.05), and the mean value at 20:00 was similar to that at 08:00. 相似文献
995.
The ontogeny of terminal deoxynucleotidyl transferase positive cells in the human fetus 总被引:6,自引:2,他引:6
The ontogeny of cells containing the enzyme terminal deoxynucleotidyl transferase (TdT) in human fetal liver, bone marrow, and thymus has been studied using a highly specific antiserum to TdT together with monoclonal antiprecursor cell antibodies in double and triple marker immunofluorescence. TdT+ cells were first observed in fetal liver at 12 wk of gestation and accounted for 55% of the lymphoid-like cells isolated after Ficoll-Hypaque separation. TdT+ cells were first observed in the bone marrow 16 wk after gestation. Like TdT+ cells in normal infant bone marrow, the majority of TdT+ cells in fetal liver and bone marrow expressed both BA-1 and RFB-1 antigens. This suggests that fetal TdT+ cells include progenitors of the B lineage (BA-1+) and perhaps of thymocytes (RFB-1+). Nevertheless, TdT was not observed in fetal thymocytes until after 20 wk of gestation, although thymic blasts and the majority of thymocytes were strongly RFB-1+ from 12 wk of gestation. These results clearly show that fetal thymus is first populated by TdT, RFB-1+, BA-1 cells, but does not exclude the fact that a second "wave" of TdT+ prothymocytes, possibly bone marrow derived, also exists. 相似文献
996.
997.
P Gurumurthy M S Krishnamurthy O Nazareth R Parthasarathy G R Sarma P R Somasundaram S P Tripathy G A Ellard 《The American review of respiratory disease》1984,129(1):58-61
The results are presented of a retrospective analysis of the incidence of jaundice among 3,000 patients with pulmonary tuberculosis and of the activities of serum aspartate aminotransferase among 850 according to their isoniazid acetylator phenotype. The patients had been treated with a variety of isoniazid-containing regimens in a series of controlled clinical trials in South India. The results show that rapid acetylators are no more prone to develop isoniazid-induced hepatic toxicity than are slow acetylators. 相似文献
998.
Accelerated echo planar J‐resolved spectroscopic imaging in prostate cancer: a pilot validation of non‐linear reconstruction using total variation and maximum entropy
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Rajakumar Nagarajan Zohaib Iqbal Brian Burns Neil E. Wilson Manoj K. Sarma Daniel A. Margolis Robert E. Reiter Steven S. Raman M. Albert Thomas 《NMR in biomedicine》2015,28(11):1366-1373
The overlap of metabolites is a major limitation in one‐dimensional (1D) spectral‐based single‐voxel MRS and multivoxel‐based MRSI. By combining echo planar spectroscopic imaging (EPSI) with a two‐dimensional (2D) J‐resolved spectroscopic (JPRESS) sequence, 2D spectra can be recorded in multiple locations in a single slice of prostate using four‐dimensional (4D) echo planar J‐resolved spectroscopic imaging (EP‐JRESI). The goal of the present work was to validate two different non‐linear reconstruction methods independently using compressed sensing‐based 4D EP‐JRESI in prostate cancer (PCa): maximum entropy (MaxEnt) and total variation (TV). Twenty‐two patients with PCa with a mean age of 63.8 years (range, 46–79 years) were investigated in this study. A 4D non‐uniformly undersampled (NUS) EP‐JRESI sequence was implemented on a Siemens 3‐T MRI scanner. The NUS data were reconstructed using two non‐linear reconstruction methods, namely MaxEnt and TV. Using both TV and MaxEnt reconstruction methods, the following observations were made in cancerous compared with non‐cancerous locations: (i) higher mean (choline + creatine)/citrate metabolite ratios; (ii) increased levels of (choline + creatine)/spermine and (choline + creatine)/myo‐inositol; and (iii) decreased levels of (choline + creatine)/(glutamine + glutamate). We have shown that it is possible to accelerate the 4D EP‐JRESI sequence by four times and that the data can be reliably reconstructed using the TV and MaxEnt methods. The total acquisition duration was less than 13 min and we were able to detect and quantify several metabolites. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
Dandapantula N Sarma Marilyn L Barrett Mary L Chavez Paula Gardiner Richard Ko Gail B Mahady Robin J Marles Linda S Pellicore Gabriel I Giancaspro Tieraona Low Dog 《Drug safety》2008,31(6):469-484
Green tea [Camellia sinensis (L.) Kuntze] is the fourth most commonly used dietary supplement in the US. Recently, regulatory agencies in France and Spain suspended market authorization of a weight-loss product containing green tea extract because of hepatotoxicity concerns. This was followed by publication of adverse event case reports involving green tea products. In response, the US Pharmacopeia (USP) Dietary Supplement Information Expert Committee (DSI EC) systematically reviewed the safety information for green tea products in order to re-evaluate the current safety class to which these products are assigned. DSI EC searched PubMed (January 1966-June 2007) and EMBASE (January 1988-June 2007) for clinical case reports and animal pharmacological or toxicological information. Reports were also obtained from a diverse range of other sources, including published reviews, the US FDA MedWatch programme, USP's MEDMARX adverse event reporting system, the Australian Therapeutic Goods Administration, the UK Medicines and Healthcare products Regulatory Agency, and Health Canada's Canadian Adverse Drug Reaction Monitoring Program. Case reports pertaining to liver damage were evaluated according to the Naranjo causality algorithm scale. In addition, the Committee analysed information concerning historical use, regulatory status, and current extent of use of green tea products. A total of 216 case reports on green tea products were analysed, including 34 reports concerning liver damage. Twenty-seven reports pertaining to liver damage were categorized as possible causality and seven as probable causality. Clinical pharmacokinetic and animal toxicological information indicated that consumption of green tea concentrated extracts on an empty stomach is more likely to lead to adverse effects than consumption in the fed state. Based on this safety review, the DSI EC determined that when dietary supplement products containing green tea extracts are used and formulated appropriately the Committee is unaware of significant safety issues that would prohibit monograph development, provided a caution statement is included in the labelling section. Following this decision, USP's DSI ECs may develop monographs for green tea extracts, and USP may offer its verification programmes related to that dietary ingredient. 相似文献
1000.