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31.
Hugo W. Moser James M. Powers Kirby D. Smith 《Brain pathology (Zurich, Switzerland)》1995,5(3):259-266
Knowledge about adrenoleukodystrophy (ALD), a disorder which was described first in 1923, has increased greatly during recent years. The principal biochemical abnormality, the presumed enzyme defect, and the gene defect, have been defined. A dietary therapy has been proposed and attracted world-wide attention through a motion picture. Nevertheless, many questions remain and cannot be answered without a more fundamental understanding of pathology and pathogenesis. This article will provide a review of the history, clinical features, pathology, biochemistry, and the gene defect, and then appraise current efforts to clarify pathogenesis and develop therapeutic approaches. 相似文献
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Floyd Thompson Julia Emerson William Dalton Jin-Ming Yang Daniel McGee Hugo Villar Sally Knox Kathy Massey Ronald Weinstein Achyut Bhattacharyya Jeffrey Trent 《Genes, chromosomes & cancer》1993,7(4):185-193
Cytogenetic analysis was performed on a selected series of short-term cultures of primary breast carcinomas from 28 patients. All patients had histopathologically confirmed malignancies, with the majority (25/28 cases) demonstrating infiltrating ductal carcinoma. All 28 cases evidenced clonal chromosome abnormalities, with 10/28 displaying only numeric aberrations, whereas 18/28 displayed clonal structural alterations. In near-diploid tumors the most common numeric changes were — 17 and — 19. However, trisomy 7 was the only numeric change in two near-diploid tumors. Structural chromosome alterations were primarily isochromosomes, apparent terminal deletions, and unbalanced non-reciprocal translocations. Chromosomes 1 (10/18–56%) and 6 (8/18–44%) were most frequently altered in this series. Breakpoints of clonal structural abnormalities were shown to cluster to several chromosome segments, including 1p22-q11, 3p11, 6p11–13, 7p11-q11, 8p11-q11, and 19q13. Analysis of the gain or loss of specific chromosome segments revealed that the most consistent tendency was over-representation of 1q, 3q, and 6p. © 1993 Wiley-Liss, Inc. 相似文献
35.
Francisco F. Nogales Alfredo Matilla Francisco Nogales-Ortiz Hugo L. Galera-Davidson 《Human pathology》1978,9(5):553-566
Four cases of polyvesicular vitelline tumor are presented; two were of a previously unreported pure type, and the other two were mixed with endodermal sinus tumor.The morphologic features of the vesicles favor an endodermal origin, as originally proposed by Teilum. Marked specialization of the vesicular lining cells, seen ultrastructurally, suggests a differentiation toward gut structures and mature yolk sac. One case of pure polyvesicular vitelline tumor showed massive erythropoiesis. We propose that the pure tumor reflects an intermediate degree of differentiation within the selectively endodermal yolk sac tumor group, that is, a further stage of organization than the endodermal sinus tumor.In our cases of pure polyvesicular vitelline tumor, the marked degree of differentiation was correlated with an improved prognosis, as in the case of the possible homologue of this tumor, the yolk sac tumor of the infant testis. In contrast, the two cases of the tumor admixed with endodermal sinus tumor illustrated the low survival rate expected in the pure endodermal sinus tumor; in these cases the metastases had no polyvesicular component. Because of the significance of such a difference in prognosis we emphasize the importance of an accurate diagnosis, suggesting that a large number of sections be taken in order to demonstrate any endodermal sinus tumor component that may be present, and that the possibility of pure polyvesicular vitelline tumor always be considered in the differential diagnosis of multicystic ovarian tumors. 相似文献
36.
Arturo Blazquez-Navarro Chantip Dang-Heine Patrizia Wehler Toralf Roch Chris Bauer Sindy Neumann Rodrigo Blazquez-Navarro Andriy Kurchenko Kerstin Wolk Robert Sabat Timm H. Westhoff Sven Olek Oliver Thomusch Harald Seitz Petra Reinke Christian Hugo Birgit Sawitzki Michal Or-Guil Nina Babel 《Transplant international》2021,34(9):1680-1688
Epstein–Barr virus (EBV) reactivation is a very common and potentially lethal complication of renal transplantation. However, its risk factors and effects on transplant outcome are not well known. Here, we have analysed a large, multi-centre cohort (N = 512) in which 18.4% of the patients experienced EBV reactivation during the first post-transplant year. The patients were characterized pre-transplant and two weeks post-transplant by a multi-level biomarker panel. EBV reactivation was episodic for most patients, only 12 patients showed prolonged viraemia for over four months. Pre-transplant EBV shedding and male sex were associated with significantly increased incidence of post-transplant EBV reactivation. Importantly, we also identified a significant association of post-transplant EBV with acute rejection and with decreased haemoglobin levels. No further severe complications associated with EBV, either episodic or chronic, could be detected. Our data suggest that despite relatively frequent EBV reactivation, it had no association with serious complications during the first post-transplantation year. EBV shedding prior to transplantation could be employed as biomarkers for personalized immunosuppressive therapy. In summary, our results support the employed immunosuppressive regimes as relatively safe with regard to EBV. However, long-term studies are paramount to support these conclusions. 相似文献
37.
38.
Hugo J. Van Staveren Hans P. A. Marijnissen Maurice C. G. Aalders Willem M. Star 《Lasers in medical science》1995,10(2):137-147
Spherical isotropic fibre optic light diffusers are used in photodynamic therapy either as a light source or as a light detector. The construction of light diffusers using different materials is described, viz. an optical method involving local polymerization of a dental fissure sealant, which is referred to as the Henderson method, and a second method using plastic or ceramic pre-fabricated spheres. Quality tests necessary for reliable clinical use are presented for the mechanical strength, output power and isotropy. The maximum pull-off force and blow-off output power for the different kinds of diffusers were determined. The calibration procedures are given for measurement of the output power and wavelength of the light emitted by a diffuser and for measurement of the fluence rate by a light-detecting diffuser, using a compact integrating sphere device. With all types of diffusers described, an isotropy can be obtained of better than ± 20% measured over a 320° angle for spheres as small as 1 mm. Larger ceramic diffusers are particularly suitable for delivering high output powers. A 3-mm-diameter ceramic diffuser mounted on a 600-m-core fibre can emit up to 5 W of continuous wave (CW) visible light in air. Diffusers used for light detection can measure the light fluence rate in tissue with 15% accuracy or better if calibration factors are determined for each individual probe. 相似文献
39.
Male and female 45-day-old mice of two inbred (CBA and C57B1) and of one outbred (OF1), SPF (specific pathogen free), strains, LD12:12 (L = 150 lx) synchronized, were submitted to an acute carbon monoxide challenge giving an overall survival close to 50%. Under these conditions significantly (P < 0.001) less CBA survived than the two other strains. A sex-related significant (P < 0.001 difference was observed in OF1. Strain survival differences are independent of body weights and of respiratory and displacement activity, but appear to be related to behavior reactions towards environmental stresses. These phenotypic differences are similar to previous findings obtained with these three strains of mice submitted to a 50% survival acute hypoxic hypoxia (M. Stupfel, A. Perramon, P. Merat, J. M. Faure, and H. Masse, 1979, Comp. Biochem. Physiol., 64A, 317–323). 相似文献
40.
Percutaneous dilatational tracheostomy (PDT) is being increasingly used. Concerns have been raised as to its safety, especially
when it is done at the bedside. A prospective evaluation was conducted of 100 consecutive, unselected critically ill patients
with PDT. The mean intensive care unit (ICU) stay before PDT was 12 days. One surgeon performed PDT alone (5 cases) or assisted
residents (95 cases) in all operations; 84 were performed at the ICU bedside. Only the first six patients were taken to the
operating room solely for tracheostomy. A modified technique was used: (1) the endotracheal tube was left in place during
sequential dilations; (2) dilators were inserted in a 60-degree cephalad orientation to the skin and directed caudally after
penetration of the anterior tracheal wall; (3) a digit was inserted through the tracheal opening to guide withdrawal of the
endotracheal tube to the level of the vocal cords; and (4) size 8 tracheostomy cannulas were inserted over 28F dilators. The
average time from skin incision to insertion of the tracheostomy tube was 12 minutes (< 10 minutes, 41 patients; 10 to 15
minutes, 37 patients; > 15 minutes, 22 patients). Sixty-five percent had unfavorable anatomic conditions due to spinal precautions
or diffuse neck edema. Postoperative complications occurred in four patients; surgical emphysema after tracheal lacerations
in three, cannula dislodgment in one. All complications were successfully managed without an operation by tube exchange (n= 3) or observation (n= 1); there was no procedure-related mortality. Forty patients were available for long-term follow-up (6–18 months after tracheostomy)
by telephone; one had persistent hoarseness without respiratory difficulty. We concluded that bedside PDT is safe and easy
to teach when performed with a technique that ensures correct instrumentation. 相似文献