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81.
82.
De Simone R Glombitza G Vahl CF Albers J Meinzer HP Hagl S 《The Annals of thoracic surgery》1999,67(2):494-499
BACKGROUND: Color Doppler echocardiography is a standard technique for assessing mitral regurgitation before and after mitral valvuloplasty. Mitral valve prolapse produces complex eccentric jet flows that cannot be visualized and measured by two-dimensional color Doppler echocardiography. The aim of this study was to evaluate the clinical impact of three-dimensional color Doppler echocardiography, a new technique developed at our institution, for assessing mitral regurgitation. METHODS: Forty-five patients with mitral regurgitation underwent intraoperative transesophageal echocardiography and three-dimensional Doppler data acquisition. The grade of mitral regurgitation was assessed by angiography. The jet areas were calculated by planimetry from conventional color Doppler; the jet volumes were obtained by three-dimensional Doppler data. RESULTS: New patterns of mitral regurgitant flows were recognized according to the origin, direction, and spatial spreading into the left atrium. Conventional jet areas failed to separate the groups of patients with different degrees of regurgitation, whereas the jet volumes were able to divide patients with different regurgitation grades. No significant correlation was found between jet area and angiographic grading (r = 0.63, p = NS). Jet volumes were significantly correlated to angiography (r = 0.89, p < 0.001). CONCLUSIONS: Three-dimensional color Doppler echocardiography revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets. 相似文献
83.
Saïd MH Layani MP Colon S Faraj G Glastre C Cochat P 《Pediatric nephrology (Berlin, Germany)》1999,13(1):39-44
Mycoplasma pneumoniae infection is a rare cause of acute nephritis. Six children (2 girls) aged 5–10 years, admitted for nephritis, had serological
tests showing recent Mycoplasma pneumoniae infection. The diagnosis of Mycoplasma pneumoniae infection was based on the presence of serum IgM, detected either by immunofluorescence (IF) (n=1) or enzyme-linked immunosorbent assay (n=5). Four children had a renal biospy, with analysis of parenchymal Mycoplasma pneumoniae components by indirect IF and polymerase chain reaction. Extrarenal symptoms were: respiratory (n=3), ear, nose, and throat (n=2), gastrointestinal (n=3), hepatic (n=1), neurological (n=1), articular (n=1), and hematological (n=3). The patients presented with acute nephritis (1 had a nephrotic syndrome) or with acute renal failure and proteinuria.
Pathological findings included type 1 membranoproliferative glomerulonephritis (MPGN, n=1), proliferative endocapillary glomerulonephritis (n=2), and minimal change disease (n=1). The patient with type 1 MPGN progressed rapidly towards end-stage renal failure because of a congenital solitary kidney.
Among the patients with endocapillary glomerulonephritis, 1 relapsed 6 months later and remained proteinuric, while the other
recovered, as did the child with minimal change disease. The search for Mycoplasma pneumoniae antigens and nucleic acids in renal tissue was negative. However, the absence of the microorganism in the kidney is a common
feature of post-streptococcal glomerulonephritis. We conclude that Mycoplasma pneumoniae is a rare yet potential cause of acute glomerulonephritis.
Received: 13 September 1996 / Revised: 16 June 1998 / Accepted: 18 June 1998 相似文献
84.
P A Modesti S Vanni R Paniccia B Bandinelli I Bertolozzi G Polidori G Sani G G Neri Serneri 《Journal of cardiovascular pharmacology》1999,34(3):333-339
On cardiac membranes and isolated cardiomyocytes from the human heart, cell-type distribution and functional activities of endothelin-1 (ET-1) receptor subtypes were investigated by using binding methods and messenger RNA (mRNA) in situ hybridization. The ET-receptor antagonist BMS-182874 selectively and competitively inhibits ET(A) receptors both on isolated myocytes and ventricular membranes with approximately 1,300 times greater affinity for ET(A) than ET(B) subtypes. The [125I]-ET-1 specific binding revealed 42.851+/-2,546 receptors/myocyte with a prevalent proportion of ET(A)-receptor subtypes on both myocytes (84+/-2%) and ventricular membranes (66+/-3%). In situ hybridization studies revealed that mRNA for ET(A) receptors was expressed on both myocytes and nonmyocyte cells, whereas mRNA for ET(B) receptors was almost exclusively expressed on fibroblasts and endothelial cells. Specific binding of [125I]-ET-1 to both myocytes and ventricular membranes in the presence of specific ET(A) (BMS-182874) and ET(B) (BQ-788)-receptor antagonists showed a displacement of [125I]-ET-1 by unlabeled ET-1, which were significantly faster from ET(B) than from ET(A). This suggests a clearance function of ventricular ET(B) receptors. 相似文献
85.
G Simone A Paradiso R Cirillo A Mangia G Rella S Wiesel S Petroni G De Benedictis M De Lena 《Pathologica》1991,83(1086):449-459
Recently, a method similar to ER.ICA has been proposed for the progesterone receptor (PgR) using two monoclonal antibodies, JZB39 and KD68, specific for human PgR and characterized by a molecular weight of 95 and 120 Kd, respectively. A series of 73 breast cancer patients was studied with regards to ER and PgR using both immunocytochemical (ICA) and biochemical (DCC) assays. Results showed no substantial differences between the two methods when considering common clinical-pathological parameters. Overall agreement between ICA and DCC methods was found: 79% for PgR and 78% for ER. A slight quantitative correlation was also observed between the "score values" of the ICA method and the Fmol content of ER and PgR using the Brave-Pearson test (r = 0.49 for PgR; r = 0.43 for ER). Specificity of PgR.ICA method was 77% for PgR and 72% for ER; sensitivity was 82% and 83%, respectively. The ICA method is a reliable technique to assess PgR presence as well as ER. Further studies are necessary to evaluate the prognostic role of nuclear PgR. 相似文献
86.
P. De Marinis A. Punzo M. Colangelo G. Ruggiero A. De Simone A. Ambrosio 《Child's nervous system》1991,7(6):353-355
A giant aneurysm of the right callosomarginal artery is reported in a 3-month-old child. This location is rare: including our case reported here, only three cases have been described. Clinicoradiological findings are presented and the surgical procedure is illustrated. 相似文献
87.
Selection bias in TEFRA at-risk HMOs 总被引:1,自引:0,他引:1
The issue of selection bias was investigated using data from 22 HMOs who are enrolling Medicare beneficiaries under Tax Equity and Fiscal Responsibility Act of 1982 (TEFRA) at-risk contracts. The study differs from previously published analyses of this issue in that it deals with the current Medicare risk program (TEFRA) rather than with earlier Demonstration Programs; as an indicator of selection bias, it utilizes beneficiary functional health status at enrollment; and it examines selection not only at the mean of the health status distribution, but at the two tails (very disabled, very able) as well. For each of the participating HMOs, the functional health status of recent Medicare enrollees was compared with that of a control group of randomly chosen fee-for-service beneficiaries. None of the HMOs experienced adverse selection, whether measured in terms of overall (mean) health status of enrollees or in terms of the proportion of the very disabled population that chose to join. Nine of the 22 HMOs were considered to have experienced favorable selection on the basis of the mean health status of new enrollees. In addition, ten more HMOs were found to have experienced favorable selection in one or both tails of the health status distribution. Although a specific cause for the observed enrollment patterns is not identified, speculation is made on factors that may or may not contribute. Evidence suggests that beneficiary self-selection is probably a more important explanation of these patterns than purposeful actions of HMOs to discourage enrollment by sicker beneficiaries (i.e., "skimming"). 相似文献
88.
Knowledge regarding human bladder smooth muscle cell (SMC) physiology is very limited. Only a few specific medical therapies
for bladder disorders have therefore been established. The objective of this study was to develop a model for videomicroscopy
of bladder SMC contractions. Cells were isolated from human cystoprostatectomy specimens and cultured in a modified EMEM medium.
These cells were identified as SMCs by means of immunohistochemistry. For videomicroscopy, the culture flasks were coated
with a viscous agent to allow cell contraction. Contractions were visualized by means of a cell culture microscope with a
time-lapse videosystem. For cholinergic stimulation of the cells, acetylcholine, in concentrations ranging from 100 μM to
10 mM, was applied. The percentage of contracting cells within the observation field was evaluated for quantitative analysis.
In control experiments without contractile stimulant 6% of the cells were observed to contract. Stimulation with acetylcholine
induced a significant dose-dependent increase to 47% in contracting cells. These results demonstrated that videomicroscopy
is an appropriate tool to investigate the contraction mechanisms of bladder SMCs. This model offers the possibility of studying
drug effects on the human detrusor in vitro.
Received: 16 September 1999 / Accepted: 1 May 2000 相似文献
89.