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991.
Joseph K. Kovach 《Behavior genetics》1993,23(4):369-377
Successful artificial selection of quail (C. coturnix japonica) for divergent early approach preferences for, and imprintabilities to, the wavelength characteristics of otherwise identical visual stimuli decreased the trait's developmental stability. The developmental error that resulted from selecting for extreme initial preferences was associated with enhanced imprintabilities. Conversely, the developmental error that resulted from selecting for extreme imprintabilities was associated with enhanced expression of directional gene effects in extreme initial preferences. The data are attributed to selectively relaxed normative canalization of trait development, and to related enhanced expression of genetic, environmental, and stochastic influences in trait deviations. 相似文献
992.
Heritability coefficients are offered for four personality source traits, measured by the O-A (objective-analytic) 2-h performance battery. Five family constellations covering a total sample of 1221 boys 12–18 years old yielded nine concrete variances which the MAVA (multiple abstract variance analysis) model resolves into seven abstract variances: 2
wg
, within family genetic; 2
wt.s
, within family threptic; 2
wt.t
, within family threptic for twins; 2
bg
, between family genetic;
bgbt
, correlation of genetic and threptic deviations across families, etc. Maximum likelihood was the method here used for the MAVA analysis. The best fit with maximum parsimony was to assume no genothreptic (
wgwt
,
bgbt
) correlations, but extension to the parsimony of assuming either no genetic or no threptic components gave no fit. The heritabilities found were compared with those from an earlier research and from a different (OSES) method applied to the present data. The agreement is quite good in assigning a moderate heritability value tocapacity to mobilize vs. regression, U.I.23 (H about 0.30), and toanxiety, U.I.24 (H about 0.50); only moderately consistent in assigning a moderateH value toasthenia, U.I.28 (H about 0.30); and poorly consistent in assigning a lowH value tonarcistic ego, U.I.26. It is pointed out (a) that the lowH for U.I.28 fits the theory of the origin of this trait well and (b) that, in view of estimates of the function fluctuation of U.I.23 and 24, a most probable conclusion is that a capacity to mobilize is quitesubstantially innate and a general proneness to anxiety islargely innate. 相似文献
993.
Objective To compare common extended-spectrum β -lactamase (ESBL) screening methods and β -lactams for their ability to detect TEM- and SHV-related ESBL enzymes.
Methods This study compared disk diffusion testing by NCCLS methodology, the Jarlier double disk test, a disk-on-disk test, a modified three-dimensional test and the E test method for their sensitivity and specificity in detecting TEM- and SHV-related ESBL producers. Three negative and 22 positive controls were studied. These were two Klebsiella pneumoniae and 23 Escherichia coli transconjugants. Seventeen β -lactam antibiotics were tested: cefamandole, cefotetan, cefoxitin, cefuroxime, cefixime, cefoperazone, cefotaxime, cefpodoxime, cefsulodin, ceftazidime, ceftibuten, ceftizoxime, ceftriaxone, moxalactam, cefepime, cefpirome and aztreonam.
Results NCCLS disk diffusion was 14% sensitive with ceftriaxone, 36% with cefotaxime, 64% with aztreonam, 68% with cefpodoxime, and 73% with ceftazidime. Cefoperazone, cefamandole, cefpodoxime and cefpirome showed 91% sensitivity using the Jarlier test. Using the disk-on-disk test, cefsulodin showed 95% sensitivity, and cefoperazone, cefepime and cefamandole showed 91% sensitivity. With the modified three-dimensional test, cefoperazone, cefpodoxime and cefpirome showed 91% sensitivity.
Conclusions For practical reasons, we would recommend use of either the Jarlier test or the commercial cephalosporin disks containing clavulanic acid to screen for ESBL producers. Cefoperazone, cefamandole, cefpodoxime and cefpirome showed good sensitivity across the methods tested. 相似文献
Methods This study compared disk diffusion testing by NCCLS methodology, the Jarlier double disk test, a disk-on-disk test, a modified three-dimensional test and the E test method for their sensitivity and specificity in detecting TEM- and SHV-related ESBL producers. Three negative and 22 positive controls were studied. These were two Klebsiella pneumoniae and 23 Escherichia coli transconjugants. Seventeen β -lactam antibiotics were tested: cefamandole, cefotetan, cefoxitin, cefuroxime, cefixime, cefoperazone, cefotaxime, cefpodoxime, cefsulodin, ceftazidime, ceftibuten, ceftizoxime, ceftriaxone, moxalactam, cefepime, cefpirome and aztreonam.
Results NCCLS disk diffusion was 14% sensitive with ceftriaxone, 36% with cefotaxime, 64% with aztreonam, 68% with cefpodoxime, and 73% with ceftazidime. Cefoperazone, cefamandole, cefpodoxime and cefpirome showed 91% sensitivity using the Jarlier test. Using the disk-on-disk test, cefsulodin showed 95% sensitivity, and cefoperazone, cefepime and cefamandole showed 91% sensitivity. With the modified three-dimensional test, cefoperazone, cefpodoxime and cefpirome showed 91% sensitivity.
Conclusions For practical reasons, we would recommend use of either the Jarlier test or the commercial cephalosporin disks containing clavulanic acid to screen for ESBL producers. Cefoperazone, cefamandole, cefpodoxime and cefpirome showed good sensitivity across the methods tested. 相似文献
994.
基于脑电复杂度的意识任务的特征提取与分类 总被引:3,自引:2,他引:3
本研究提出了利用事件相关脑电复杂度提取大脑运动意识特征,应用Mahalanobis距离判别式分析法,对人脑想象左右手运动任务进行分类,获得了满意的结果。对受试者想象左右手运动期间在大脑初级感觉运动皮层区记录的脑电信号采用复杂度分析方法量化了事件相关去同步(ERD)和事件相关同步(ERS)时程,结果表明EEG复杂度特征较好反映了ERD/ERS变化时程。最后对测试数据进行分类,最大分类正确率达到86.43%,通过最大分类正确率,最大信噪比,最大互信息等评价指标比较,验证了该方法的有效性,从而为大脑运动意识任务的特征提取及分类提供了新思路。 相似文献
995.
Y. Sato K. Morise Y. Saito K. Kusugami M. Ito 《Virchows Archiv : an international journal of pathology》1996,429(6):377-382
To determine whether primary B-cell gastric lymphoma (GL) is one entity, we examined the expression of three adhesion molecules in the microvasculature of lymphomas. Stromal cells, including vascular endothelial cells, within lymphoid follicles of the gastric mucosa were also investigated. Twenty-two surgical specimens of GL were classified into low-grade malignant lymphoma arising from mucosa-associated lymphoid tissue (low-grade lymphoma, n=9), and high-grade malignant lymphoma with (secondary high-grade lymphoma, n=6) or without (primary high-grade lymphoma, n=7) a low-grade component. The proportion of venules positive for ELAM-1 or VCAM-1 was significantly higher (P<0.001) in primary high-grade lymphoma than in low-grade and secondary high-grade lymphomas. In gastric lymphoid follicles, the stromal cells of the germinal centre (GC) were positive for ICAM-1, ELAM-1, and VCAM-1, but the stromal cells of the marginal zone (MZ) were positive only for ICAM-1. We found two patterns of adhesion molecule expression in gastric lymphoid follicles, the MZ pattern and the GC pattern. Low-grade and secondary high-grade lymphomas, which had the MZ pattern, might be of MZ-cell lineage, but most primary high-grade lymphomas, which had the GC pattern, might be of follicular centre cell lineage. 相似文献
996.
用Instron试验机对新鲜夫股骨密质骨试样进行一维拉伸实验研究,利用实验结果对由平行粘弹性杆系统建立的密质骨损伤本构模型待定参数进行拟合,获得较高的相关系数和较好的显著性水平。 相似文献
997.
T. N. Ivanova E. D. Polyakova A. M. Olfer'ev N. V. Perova 《Bulletin of experimental biology and medicine》1998,125(5):505-508
The rate of cholesterol synthesis in peripheral blood lymphocytes and plasma lipid and lipoprotein spectra are studied in
patients with isolated hypercholesterolemia and combined hyperlipidemias (IIa and IIb hyperlipidemias according to Frederickson
classification).14C-acetate incorporation into cholesterol in peripheral blood lymphocytes is considerably higher in patients with type IIb
hyperlipidemia. Lipanthyl-200M reduces the rate of cholesterol synthesis in lymphocytes of both groups. A direct correlation
is established between serum triglyceride level and the rate of cholesterol synthesis.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 5, pp. 569–573, May, 1998 相似文献
998.
Morphological detection and quantification of lipoprotein(a) deposition in atheromatous lesions of human aorta and coronary arteries 总被引:8,自引:0,他引:8
Axel Niendorf Matthias Rath Katrin Wolf Susanne Peters Hartmut Arps Ulrike Beisiegel Manfred Dietel 《Virchows Archiv : an international journal of pathology》1990,417(2):105-111
Summary Lipoprotein(a), as an atherogenic particle, represents an independent risk factor for coronary heart disease. In the present
study the morphological distribution of apoprotein (a) and apoprotein B within the arterial wall is described. Apoprotein
B, a constituent of very low-density lipoprotein, low-density lipoprotein and lipoprotein(a) has previously been demonstrated
in atheromatous lesions. Lipoprotein(a) possesses an additional protein, designated apoprotein (a). Autopsy material (n=74) from the left coronary artery and from the thoracic aorta has been examined by means of immunohistochemistry and both
apoprotein (a) and apoprotein B were detected, primarily associated with the extracellular matrix and accumulating in lesions
in the arterial wall. The staining pattern for both antigens was almost always found to be congruent, suggesting that the
detection of (a)-antigen has to be attributed at least in part to the presence of lipoprotein(a). It is concluded that both
low-density lipoprotein and lipoprotein(a) have an important role in the pathogenesis of atherosclerosis. 相似文献
999.
目的:在钙化大鼠主动脉血管平滑肌细胞上观察血管紧张素-(1-7)[Angiotensin-(1-7)]对钙化的影响及其信号通道。方法:用β-磷酸甘油制备钙化的大鼠血管平滑肌细胞,再以血管紧张素-(1-7)、血管紧张素Ⅱ、血管紧张素Ⅱ 血管紧张素-(1-7)、选择性蛋白激酶A(PKA)或蛋白激酶C(PKC)抑制剂等干预,通过Von Kossa染色及检测钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达来探讨血管紧张素Ⅱ对钙化的影响及其信号通道。结果:血管紧张素-(1-7)抑制钙化大鼠血管平滑肌细胞的钙含量、碱性磷酸酶活性(P>0.05)、骨钙素浓度和Cbfa1 mRNA表达(P<0.05),也抑制血管紧张素Ⅱ对血管平滑肌细胞的钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达的促进作用(P<0.05);血管紧张素-(1-7)提高血管平滑肌细胞内cAMP浓度(P<0.05),PKA抑制剂可阻断血管紧张素-(1-7)对钙化血管平滑肌细胞的钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达的抑制作用(P<0.05)。结论:血管紧张素-(1-7)可抑制β-磷酸甘油诱导的血管平滑肌细胞钙化,并拮抗血管紧张素Ⅱ促进的血管平滑肌细胞钙化;这些效应与cAMP-PKA-Cbfa1信号途径有关。 相似文献
1000.
J Top N M I Banga R Hayes R J Willems M J M Bonten M K Hayden 《Clinical microbiology and infection》2008,14(4):363-369
In order to assess whether multiple-locus-variable number tandem repeat analysis (MLVA) could replace pulsed-field gel electrophoresis (PFGE) for genotyping vancomycin-resistant isolates of Enterococcus faecium (VREF), this study compared the typeability, discriminatory power, concordance and costs of these methods for VREF isolates obtained from patients, environmental samples and the hands of healthcare workers (HCWs) in a medical intensive care unit (ICU) where VREF was endemic. Over a 58-day period, 393 VREF isolates (373 vanA, one vanA/B, 19 vanB) were cultured from patient rectal swabs (n = 76), the environment (n = 270) and the hands of HCWs (n = 47). PFGE was able to divide 358 (91.1%) isolates into 19 PFGE types (>six bands different) and 24 subtypes (one to three bands different). MLVA was able to type 391 (99.5%) isolates into 11 genotypes. The discriminatory power of PFGE subtypes was 83%, as compared to 68% for MLVA. Concordance between the two methods, based on matched or mismatched MLVA types and PFGE types or subtypes, was 67.5% and 82.8%, respectively. Using PFGE, 13 isolates could be genotyped in 3 days; MLVA genotyped 94 isolates in 2 days. For both methods, the estimated costs were Euro 7 ($10)/isolate. PFGE and MLVA produced highly concordant results when assigning genotypes to nosocomial VREF isolates. MLVA was faster, but PFGE subtyping was more discriminatory. 相似文献