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991.
992.
Martin Soehle Marek Czosnyka Doris A Chatfield Andreas Hoeft Alonso Pe?a 《Journal of cerebral blood flow and metabolism》2008,28(1):64-73
Higher biologic systems operate far from equilibrium resulting in order, complexity, fluctuation of inherent parameters, and dissipation of energy. According to the decomplexification theory, disease is characterized by a loss of system complexity. We analyzed such complexity in patients after subarachnoid hemorrhage (SAH), by applying the standard technique of variability analysis and the novel method of fractal analysis to middle cerebral artery blood flow velocity (FV) and arterial blood pressure (ABP). In 31 SAH -patients, FV (using transcranial Doppler sonography) and direct ABP were measured. The standard deviations (s.d.) and coefficients of variation (CV=relative s.d.) for FV and ABP time series of length 2(10) secs were calculated as measures of variability. The spectral index beta(low) and the Hurst coefficient H(bdSWV) were analyzed as fractal measures. Outcome was assessed 1 year after SAH according to the Glasgow Outcome Scale (GOS). Both FV (beta(low)=2.2+/-0.4, mean+/-s.d.) and ABP (beta(low)=2.3+/-0.4) were classified as nonstationary (fractal Brownian motion) signals. FV showed significantly (P<0.05) higher variability (CV=7.2+/-2.5%) and Hurst coefficient (H(bdSWV)=0.26+/-0.13) as compared with ABP (CV=5.5+/-2.7%, H(bdSWV)=0.19+/-0.11). Better outcome (GOS) correlated significantly (P<0.05) with higher s.d. of FV (Spearman's r(s)=0.51, r(s)(2)=0.26) and ABP (r(s)=0.57, r(s)(2)=0.32), as well as with a higher Hurst coefficient of ABP (r(s)=0.46, r(s)(2)=0.21). Cerebral vasospasm reduced CV of FV, but left H(bdSWV) unchanged. FV and ABP fluctuated markedly despite homeostatic control. A reduced variability of FV and ABP might indicate a loss of complexity and was associated with a less favorable outcome. Therefore, the decomplexification theory of illness may apply to SAH. 相似文献
993.
BACKGROUND: The objective of this study was to assess the short-term impact of air pollution with sulfur dioxide (SO2), total suspended particles (TSP), nitrogen dioxide (NO2) and black smoke (BS) on the daily number of deaths in the metropolitan area of Bilbao. METHODS: The EMECAM project protocol was followed. RESULTS: Increases in TSP, in both maximum hourly figures and daily averages, are significantly associated with increases in the daily number of deaths from all causes, from circulatory causes and from all causes among those older than 70. No differences between six-month periods were found. NO2 average levels were associated with daily mortality from respiratory causes in the entire period and during the warm season, and from all causes among those older than 70 in the cool months. CONCLUSIONS: TSP levels are associated with daily mortality in the metropolitan area of Bilbao. The relationship between NO2 and the number of deaths from respiratory causes, very high in the warm season, needs further research to assess its independence. 相似文献
994.
Isolated cerebral aspergillosis without a portal of entry-complete recovery after liposomal amphotericin B and surgical treatment 总被引:1,自引:0,他引:1
Garcia A; Mazuecos A; Clavo A; Perez-Requena J; Mangas A; Alonso F; Ceballos M; Rivero M 《Nephrology, dialysis, transplantation》1998,13(9):2385-2387
Key words: Aspergillus cerebral abscess; liposomal
amphotericin B; renal transplantation
相似文献
995.
Coronary CT angiography. 总被引:7,自引:0,他引:7
Udo Hoffmann Maros Ferencik Ricardo C Cury Antonio J Pena 《Journal of nuclear medicine》2006,47(5):797-806
Advances in multidetector CT (MDCT) technology with submillimeter slice collimation and high temporal resolution permit contrast-enhanced imaging of coronary arteries and coronary plaque during a single breath hold. Appropriate patient preparation, detailed technical and technological knowledge with regard to recognition of typical imaging artifacts (such as beam hardening or motion artifacts), and the adequate choice of postprocessing techniques to detect stenosis and plaque are prerequisites to achieving diagnostic image quality. A growing number of studies have suggested that 64-slice coronary CT angiography is highly accurate for the exclusion of significant coronary artery stenosis (>50% luminal narrowing), with negative predictive values of 97%-100%, in comparison with invasive selective coronary angiography. In addition, several studies have indicated that MDCT also can detect calcified and noncalcified coronary atherosclerotic plaques, especially in proximal vessel segments, showing a good correlation with intracoronary ultrasound. Studies on clinical utility, cost, and cost-effectiveness are now warranted to demonstrate whether and how this technique can change and improve the current management of patients with suspected or confirmed coronary artery disease. 相似文献
996.
Omar Alonso Miguel Martínez Lucía Delgado Ana De León Daniela De Boni Graciela Lago Mariela Garcés Flávia Fontes José Espasandín Julio Priario 《Journal of nuclear medicine》2003,44(10):1561-1565
Most first relapses in patients with melanoma occur in regional lymph node basins. Such lesions are frequently diagnosed clinically during the first 2 y of follow-up. In the last few years, our group has been studying the usefulness of (99m)Tc-methoxyisobutylisonitrile (MIBI) scintigraphy in the evaluation of recurrent melanoma lesions. The aim of the present study was to prospectively evaluate the clinical value of (99m)Tc-MIBI scintigraphy in the diagnosis of subclinical nodal metastases. METHODS: We included 66 patients within 3 mo of melanoma diagnosis, with Breslow thickness > 1.0 mm, all treated with wide local excision of the primary lesion. When (99m)Tc-MIBI scanning was performed, 49 of them did not have evidence of nodal disease, and 17 had clinically questionable regional lymph node lesions. Planar images of lymph node regions were acquired 10 min after injection, using a dose of 740-1,110 MBq and a large-field-of-view gamma camera equipped with a low-energy high-resolution collimator. Scan findings were confirmed by pathology or by clinical follow-up (median, 35 mo). RESULTS: Thirty of 33 patients with regional lymph node metastases received a correct diagnosis, 14 with palpable lesions and 16 with nonpalpable lesions. In 3 cases that were initially (99m)Tc-MIBI negative, nodal metastases were found during follow-up. The following diagnostic values were calculated: sensitivity, 0.91 (95% confidence interval [CI], 0.75-0.98); specificity, 0.85 (95% CI, 0.67-0.94); likelihood ratio of a positive test, 6.0 (95% CI, 2.7-13.5); and likelihood ratio of a negative test, 0.11 (95% CI, 0.036-0.32). CONCLUSION: (99m)Tc-MIBI scanning may have a secondary role in the staging of regional lymph nodes in patients with clinically localized melanoma who are not good candidates for sentinel node biopsy. 相似文献
997.
I Gallo A Sáenz C Alonso M Larman R Tellería J Go?i R Arrue A Díaz del Río B Ruiz J L Ubago 《Revista espa?ola de cardiología》1991,44(1):22-27
The internal mammary artery is widely recognized as the graft of choice for coronary artery bypass grafting at present. Alternative conduits have been investigated in order to find other adequate long-term grafts. The right gastroepiploic artery has been recently used as a graft to bypass distal coronary vessels. From November 1989 to April 1990 we have implanted this artery in 33 cases (32 in situ and one free grafts). The pedicled grafts were implanted in 17 patients in the main right coronary artery, in 13 we grafted the right distal branches, in one the left anterior descending, and the circumflex branch in one. The free graft was implanted in the first diagonal. Mean grafts per patient was of three in this series, with a mean of 2 arterial grafts per patient. One patient died in the early postoperative period. The remaining patients had an uncomplicated postoperative period. Thirteen patients underwent graft and coronary angiography. Direct or indirect graft patency was confirmed in all cases. The final important issue concerning the long-term patency of this graft will be solved in the future, but short-term patency rates of the right gastroepiploic artery can be anticipated when proper techniques are used. 相似文献
998.
Ana Bella Alonso Sedano Mª Luz Tascón Garcı́a Mª Dolores Vázquez Barbado Pedro Sánchez Batanero 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,566(2):433-441
The electrochemical behaviour of different solid samples, such as Cu2O(s), CuO(s), Fe2O3(s), Fe3O4(s) and their binary mixtures, has been studied using the voltammetry of immobilised microparticles technique. These studies were carried out by using an electrode with a glassy tube and a plastic piston, containing a mass of carbon paste bound with liquid paraffin. The voltammograms obtained were utilised for the characterization of the copper ferrites Cu0.5Fe2.5O4, Cu0.7Fe2.3O4, and CuFe2O4. 相似文献
999.
J Domínguez Ortega F León J C Martínez Alonso A Alonso Llamazares E Roldán T Robledo M Mesa A Bootello C Martinez-Cócera 《Journal of investigational allergology & clinical immunology》2004,14(2):108-113
BACKGROUND: Bronchial mucosal inflammation is the major pathogenic process in asthma. In the latest years, induced sputum (IS) examination has become an important non-invasive method of assessing airway inflammation. Flow cytometry has been recently applied to the study of IS though it is not exempt of methodological difficulties. The aim of the present study was to further study if the fluorocytometric analysis of IS could represent a reliable tool to assess the presence of bronchial activated lymphocytes in stable mild asthmatic patients. METHODS: Induced sputa from controls and asthmatic patients were processed in isotonic 3mM dithiothreitol (DTT), a mucolytic agent required for cell dispersion. The individualized cells were then stained with monoclonal antibodies for three-colour flow-cytometric analysis. Total IgE and ECP were measured in serum and in the sputum fluid phase. RESULTS: The cellularity of asthmatic sputa is enriched in eosinophils (mean, 26.63%) with respect to controls, but not in lymphocytes. However, lymphocytes from asthmatics show increased surface expression of activation markers (CD25 in T cells, CD23 in B cells). Surprisingly, no differences were observed in the detected levels of CD54 on IS lymphocytes and eosinophils between asthmatics and non-asthmatics. Furthermore, there was a significantly higher concentration of ECP and total IgE in the sputum from the asthmatic group. CONCLUSION: Fluorocytometric analysis of induced sputum is a reliable non-invasive method for the study of bronchial immune cells. It could provide complementary information on activated cells in the bronchial mucosa even in non-smokers, mild and stable asthmatics and it is reasonable to speculate that it will be useful in monitoring the effect of the treatment in these patients. 相似文献
1000.
J M Fernández Vozmediano N Alonso Blasi F Alonso Trujillo M A Romero Cabrera S Gomez Salvador A Fernandez-Repeto y Valls 《Annales de dermatologie et de vénéréologie》1992,119(3):197-200
We present a very typical case of pseudo-xanthoma elasticum (PXE) with very remarkable cutaneous lesions, a great number of angioid streaks and, at the moment, with no involvement of the peripheral vascular system. From a genetic standpoint, we believe it must be considered as recessive Type I. An X-ray microanalysis was performed showing intense Ca and P deposits in the affected areas as well as complete absence of Si. 相似文献