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111.
Assignment of CDC weak oxidizer group 2 (WO-2) to the genus Pandoraea and characterization of three new Pandoraea genomospecies 下载免费PDF全文
Daneshvar MI Hollis DG Steigerwalt AG Whitney AM Spangler L Douglas MP Jordan JG MacGregor JP Hill BC Tenover FC Brenner DJ Weyant RS 《Journal of clinical microbiology》2001,39(5):1819-1826
CDC weak oxidizer group 2 (WO-2) consists of nine phenotypically similar human clinical isolates received by the Centers for Disease Control and Prevention between 1989 and 1998. Four of the isolates were from blood, three were from sputum, and one each was from bronchial fluid and maxillary sinus. All are aerobic nonfermentative, motile gram-negative rods with one to eight polar flagella per cell. All grew at 25 and 35 degrees C and were positive for catalase, urease (usually delayed 3 to 7 days), citrate, alkalinization of litmus milk, oxidization of glycerol (weakly), and growth on MacConkey agar and in nutrient broth without NaCl. All except one strain were oxidase positive with the Kovács method, and all except one isolate weakly oxidized D-glucose. All were negative for oxidation of D-xylose, D-mannitol, lactose, sucrose, maltose, and 20 other carbohydrates, esculin hydrolysis, indole production, arginine dihydrolase, and lysine and ornithine decarboxylase. Only two of nine isolates reduced nitrate. Broth microdilution susceptibilities were determined for all strains against 13 antimicrobial agents. Most of the strains were resistant to ampicillin, extended-spectrum cephalosporins, and aminoglycosides, including gentamicin, tobramycin, and amikacin, but they varied in their susceptibility to fluoroquinolones. High-performance liquid chromatographic and mass spectrometric analyses of the WO-2 group identified ubiquinone-8 as the major quinone component. The percent G+C of the WO-2 strains ranged from 65.2 to 70.7% (thermal denaturation method). All shared a common cellular fatty acid (CFA) profile, which was characterized by relatively large amounts (7 to 22%) of 16:1omega7c, 16:0, 17:0cyc, 18:1omega7c, and 19:0cyc(11-12); small amounts (1 to 3%) of 12:0 and 14:0; and eight hydroxy acids, 2-OH-12:0 (4%), 2-OH-14:0 (trace), 3-OH-14:0 (12%), 2-OH-16:1 (1%), 2-OH-16:0 (3%), 3-OH-16:0 (4%), 2-OH-18:1 (2%), and 2-OH-19:0cyc (3%). This profile is similar to the CFA profile of Pandoraea, a recently described genus associated with respiratory infections in cystic fibrosis patients (T. Coenye et al., Int. J. Syst. Evol. Microbiol., 50:887-899, 2000). Sequencing of the 16S rRNA gene (1,300 bp) for all nine strains indicated a high level (> or =98.8%) of homogeneity with Pandoraea spp. type strains. DNA-DNA hybridization analysis (hydroxyapatite method; 70 degrees C) confirmed the identity of WO-2 with the genus Pandoraea and assigned three strains to Pandoraea apista and three to Pandoraea pnomenusa, and identified three additional new genomospecies containing one strain each (ATCC BAA-108, ATCC BAA-109, ATCC BAA-110). This study also shows that Pandoraea isolates may be encountered in blood cultures from patients without cystic fibrosis. 相似文献
112.
This study examines the associations, and possible causal relationship, between mothers' authoritarian attitudes to discipline
and child behaviour using cross-sectional and prospective data from a large population sample surveyed in the 1970 British
Cohort Study. Results show a clear linear relationship between the degree of maternal approval of authoritarian child-rearing
attitudes and the rates of conduct problems at age 5 and age 10. This association is independent of the confounding effects
of socio-economic status and maternal psychological distress. Maternal authoritarian attitudes independently predicted the
development of conduct problems 5 years later at age 10. The results of this longitudinal study suggest that authoritarian
parenting attitudes expressed by mothers may be of significance in the development of conduct problems.
Accepted: 29 January 2003
Correspondence to Dr. A. Thompson 相似文献
113.
Lark RK Lester GE Ontjes DA Blackwood AD Hollis BW Hensler MM Aris RM 《The American journal of clinical nutrition》2001,73(3):602-606
BACKGROUND: Osteoporosis diminishes the quality of life in adults with cystic fibrosis (CF). Vitamin D deficiency resulting from malabsorption may be a factor in the etiology of low bone mineral density (BMD) in patients with CF. OBJECTIVE: Absorption of oral ergocalciferol (vitamin D2) and the consequent response of 25-hydroxyvitamin D in 10 adults with CF and exocrine pancreatic insufficiency was compared with that of 10 healthy control subjects. DESIGN: In this pharmacokinetic study, CF patients and control subjects were pair-matched on age, sex, and race. Each subject consumed 2500 microg oral vitamin D2 with a meal. The CF group also took pancreatic enzymes that provided > or = 80000 U lipase. Blood samples were obtained at baseline and at 5, 10, 24, 30, and 36 h after vitamin D2 consumption to measure serum vitamin D2 and 25-hydroxyvitamin D concentrations. RESULTS: Vitamin D2 concentrations in all subjects were near zero at baseline. CF patients absorbed less than one-half the amount of oral vitamin D2 that was absorbed by control subjects (P < 0.001). Absorption by the CF patients varied greatly; 2 patients absorbed virtually no vitamin D2. The rise in 25-hydroxyvitamin D in response to vitamin D2 absorption was significantly lower over time in the CF group than in the control group (P = 0.0012). CONCLUSIONS: Vitamin D2 absorption was significantly lower in CF patients than in control subjects. These results may help explain the etiology of vitamin D deficiency in CF patients, which may contribute to their low BMD. 相似文献
114.
Ankle brachial pressure index in systemic sclerosis: influence of disease subtype and anticentromere antibody 总被引:2,自引:0,他引:2
OBJECTIVE: To test the hypothesis that patients with limited cutaneous systemic sclerosis (SSc) have a higher incidence of lower limb large vessel disease than patients with diffuse cutaneous disease, and that anticentromere antibody is a risk factor for lower limb large vessel disease. METHODS: Clinical and laboratory data from 119 patients with SSc (91 patients with limited cutaneous disease, 28 patients with diffuse cutaneous disease) who had bilateral ankle brachial pressure indices (ABPI) measured between March 1997 and January 2000 were reviewed retrospectively. RESULTS: There was no evidence of reduced ABPI in limited cutaneous disease (P=0.65), average reduction 0.01 [95% confidence interval (CI) -0.04 to +0.07]. There was some suggestion of reduced ABPI in anticentromere-positive patients (P=0.12), average reduction 0.04 (95% CI -0.01 to +0.09). CONCLUSIONS: The severity of large vessel macrovascular disease, as assessed by ABPI, is not dependent on disease subtype. Anticentromere antibody may be weakly associated with a reduction in ABPI. 相似文献
115.
空心胶囊中残留氯乙醇的测定方法改进 总被引:1,自引:0,他引:1
目的:改进空心胶囊中残留氯乙醇的测定方法。方法:利用大口径毛细管柱的“溶剂效应”技术,进行测定。结果;色谱图重现性佳,分离效果好。结论;对氯乙醇的测定中,采用大口径毛细管柱分离效果优于固定液为聚乙二醇-1500的填充性。 相似文献
116.
Hollis L McGeer JC McDonald DG Wood CM 《Aquatic toxicology (Amsterdam, Netherlands)》2000,51(1):93-105
The objectives of the study were to determine the physiological and toxicological effects of chronic cadmium exposure on juvenile rainbow trout in soft water. Particular attention focused on acclimation, on comparison to an earlier hard water study, and on whether a gill surface binding model, originally developed in dilute soft water, could be applied in this water quality to fish chronically exposed to Cd. Juvenile rainbow trout, on 3% of body weight daily ration, were exposed to 0 (control), 0.07, and 0.11 microg l(-1) Cd [as Cd(NO(3))(2).4H(2)O] in synthetic soft water (hardness=20 mg l(-1) as CaCO(3), alkalinity=15 mg l(-1) as CaCO(3), pH 7.2) for 30 days. Mortality was minimal for all treatments (up to 14% for 0.11 microg l(-1) Cd). No significant effects of chronic Cd exposure were seen in growth rate, swimming performance (stamina), routine O(2) consumption, or whole body/plasma ion levels. In contrast to the hard water study, no acclimation occurred in either exposure group in soft water, with no significant increases in 96-h LC(50) values. Cadmium accumulated in a time-dependent fashion to twice the control levels in the gills and only marginally in the liver by 30 days. No significant Cd accumulation occurred in the gall bladder or whole body. Cadmium uptake/turnover tests were run using radioactive 109Cd for acute (3 h) exposures. Saturation of the gills occurred for control fish but not for Cd-exposed fish when exposed to up to 36 microg l(-1) Cd for 3 h. Cd-exposed trout accumulated less 'new' Cd in their gills compared to controls and they internalized less 109Cd than control fish. This effect of lowered Cd uptake by the gills of acclimated trout was earlier seen for the fish acclimated to 10 microg l(-1) Cd in hard water. The affinity of the gill for Cd was greater in hard water (logK(Cd-gill)=7.6) than in soft water (logK(Cd-gill)=7.3) but the number of binding sites (B(max)=0.20 microg g(-1) gill) was similar in both media. In addition, there was a shift in affinity of the gill for Cd (i.e. lowered logK(Cd-gill)) and increased B(max) with chronic Cd exposure in both soft water and hard water. We conclude that the present gill modelling approach (i.e. acute gill surface binding model or Biotic Ligand Model) does work for soft and hard water exposures but there are complications when applying the model to fish chronically exposed to cadmium. 相似文献
117.
118.
Rationale
Social stress has been linked to several neuropsychiatric diseases, including depression, which is a debilitating disease that has genetic, environmental, and epigenetic underpinnings. 相似文献119.
Edmund R. Hollis II Pouya Jamshidi Karin L?w Armin Blesch Mark H. Tuszynski 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(17):7215-7220
Several experimental manipulations of the CNS environment successfully elicit regeneration of sensory and bulbospinal motor axons but fail to elicit regeneration of corticospinal axons, suggesting that cell-intrinsic mechanisms limit the regeneration of this critical class of motor neurons. We hypothesized that enhancement of intrinsic neuronal growth mechanisms would enable adult corticospinal motor axon regeneration. Lentiviral vectors were used to overexpress the BDNF receptor trkB in layer V corticospinal motor neurons. After subcortical axotomy, trkB transduction induced corticospinal axon regeneration into subcortical lesion sites expressing BDNF. In the absence of trkB overexpression, no regeneration occurred. Selective deletion of canonical, trkB-mediated neurite outgrowth signaling by mutation of the Shc/FRS-2 activation domain prohibited Erk activation and eliminated regeneration. These findings support the hypothesis that the refractory regenerative state of adult corticospinal axons can be attributed at least in part to neuron-intrinsic mechanisms, and that activation of ERK signaling can elicit corticospinal tract regeneration. 相似文献
120.
N. L. Shaper J. H. Shaper V. Bertness H. Chang I. R. Kirsch G. F. Hollis 《Somatic Cell and Molecular Genetics》1986,12(6):633-636
The structural gene for galactosyltransferase (glycoprotein 4-B-galactosyltransferase, EC 2.4.1.38) was localized to human chromosome 9 band p13 by chromosome in situ hybridization using a cloned bovine galactosyltransferase cDNA probe. This chromosomal location is at the same position to which galactose-1-phosphate uridyltransferase, an enzyme which provides the nucleotide sugar substrate (UDP-galactose) for galactosyltransferase, has been mapped. 相似文献