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11.
The prolonged effect of nickel chloride and cadmium chloride on the rat fetal myocardium was studied experimentally administered to the pregnant mother through a gastric tube in doses of 12.5 mg/b. wt. It could be demonstrated that, due to nickel administration, changes simulating cardiomyopathy and severe mitochondrial lesions developed and the number of collagenous fibres and glycogen granules accumulated, while as a result of cadmium chloride administration, changes were apparent mainly in the endothelial cells, but with simultaneous mitochondrial impairments, too. Nickel and cadmium are contained by cigarette smoke. Based on experimental studies, authors propose new arguments on the damaging effect of smoking of pregnant women. 相似文献
12.
Harold P. Schedl Helen D. Wilson Ron L. Horst Karla Christensen Kice Brown 《Nutrition Research》1992,12(12):1541-1547
The circulating concentration of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] is a physiologic index of enzymatic activity of the renal 1-hydroxylase of 25-hydroxychole-calciferol (25-OH-D3). Hydroxylation of 25-OH-D3 and circulating 1,25-(OH)2D3 are decreased in the streptozotocin diabetic rat. We previously found that activity of another redox enzyme system, cytosolic superoxide dismutase, also decreased in streptozotocin diabetes, can be restored by treatment with glutathione. In the present experiment we tested the effect of glutathione treatment on vitamin D metabolism in control and diabetic rats. Enteral glutathione increased circulating 1,25-(OH)2D3 and decreased 25-OH-D3 in both control and diabetic animals. These results suggest that exogenous glutathione increases 25-OH-D3 1-hydroxylation both under basal conditions in the normal animal and in diabetes-induced depression. 相似文献
13.
Lima JO dos Santos JK Pereira JF de Resende ML de Araújo EF de Queiroz MV 《Current genetics》2003,42(4):236-240
Protoplasts of the pathogenic plant fungus, Crinipellis perniciosa, were transformed to hygromycin B resistance using the pAN7-1 plasmid, which contains the Escherichia coli hph gene under the control of Aspergillus nidulans regulatory sequences. The pAN7-1 plasmid was introduced by PEG/CaCl(2) treatment. Transformation frequencies of 1.6-2.5 transformants/microg of DNA were achieved. About 54% of the transformants were abortive and 40 analyzed transformants were mitotically stable and showed different hygromycin B resistance levels. The presence of the hph gene was checked by PCR in five transformants and the integration of multiple plasmid copies into different genome sites was observed by Southern analysis. This is the first report of a C. perniciosa transformation system and represents an important step for further research into genetic manipulation of this fungal plant pathogen. 相似文献
14.
Attila Patocs Peter Gergics Katalin Balogh Miklos Toth Ferenc Fazakas Istvan Liko Karoly Racz 《BMC medical genetics》2008,9(1):29
Von Hippel-Lindau disease (VHL) is a rare autosomal dominant disease characterized by development of cystic and tumorous lesions
at multiple sites, including the brain, spinal cord, kidneys, adrenals, pancreas, epididymis and eyes. The clinical phenotype
results from molecular abnormalities of the VHL tumor suppressor gene, mapped to human chromosome 3p25-26. The VHL gene encodes two functionally active VHL proteins due to the presence of two translational initiation sites separated by
53 codons. The majority of disease-causing mutations have been detected downstream of the second translational initiation
site, but there are conflicting data as to whether few mutations located in the first 53 codons, such as the Pro25Leu could
have a pathogenic role. In this paper we report a large Hungarian VHL type 2 family consisting of 32 members in whom a disease-causing
AGT80AAT (Ser80Ile) c.239G>A, p.Ser80Ile mutation, but not the concurrent CCT25CTT (Pro25Leu) c.74C>T, p.Pro25Leu variant
co-segregated with the disease. To our knowledge, the Ser80Ile mutation has not been previously described in VHL type 2 patients
with high risk of pheochromocytoma and renal cell cancer. Therefore, this finding represents a novel genotype-phenotype association
and VHL kindreds with Ser80Ile mutation will require careful surveillance for pheochromocytoma. We concluded that the Pro25Leu
variant is a rare, neutral variant, but the presence such a rare gene variant may make genetic counseling difficult. 相似文献
15.
Cytogenetic analyses of three papillary carcinomas and a follicular adenoma of the thyroid 总被引:2,自引:0,他引:2
E Olah E Balogh F Bojan F Juhasz V Stenszky N R Farid 《Cancer Genetics and Cytogenetics》1990,44(1):119-129
Cytogenetic data of three papillary carcinomas and a follicular adenoma using direct preparations or cell cultures or both after 7 to 60 days in vitro are presented. Although karyotype of the follicular adenoma proved completely normal, in each of the three papillary carcinomas a modal chromosome number in the diploid range and a deleted 11q were observed. In case 1 the del(11)(q23) was associated with rearrangement of chromosome 1 and other marker chromosomes. Our results suggest that 11q deletion may be specific for papillary carcinoma of the thyroid. 相似文献
16.
A/J and C57BL/6J mice behave differently in tests for alcohol preference, open-field activity, defecation in the open field, cricket attacking, and rope climbing. Chimeric mice, i.e., mice containing both A/J cells and C57BL/6J cells, were constructed and tested for these behaviors. Patterns of behavior among A/JC57BL/6J chimeras are such as to suggest that none of these behavior differences is controlled by a single cell or clone and that the same cell population that gives rise to the strain difference in alcohol preference also gives rise to the differences in open-field activity and defecation, while separate cell populations control cricket killing and rope climbing.This research was supported by Research Grants AA 00388 and HD 03015 to M. N. N. and MH 18996 to K. B. Computing assistance was obtained from the Health Sciences Computing Facility, UCLA, supported by NIH Special Research Resources Grant RR-3. 相似文献
17.
The neural mechanism that mediates perceptual filling-in of the blind spot is still under discussion. One hypothesis proposes that the cortical representation of the blind spot is activated only under conditions that elicit perceptual filling-in and requires congruent stimulation on both sides of the blind spot. Alternatively, the passive remapping hypothesis proposes that inputs from regions surrounding the blind spot infiltrate the representation of the blind spot in cortex. This theory predicts that independent stimuli presented to the left and right of the blind spot should lead to neighboring/overlapping activations in visual cortex when the blind-spot eye is stimulated but separated activations when the fellow eye is stimulated. Using functional MRI, we directly tested the remapping hypothesis by presenting flickering checkerboard wedges to the left or right of the spatial location of the blind spot, either to the blind-spot eye or to the fellow eye. Irrespective of which eye was stimulated, we found separate activations corresponding to the left and right wedges. We identified the centroid of the activations on a cortical flat map and measured the distance between activations. Distance measures of the cortical gap across the blind spot were accurate and reliable (mean distance: 6-8 mm across subjects, SD approximately 1 mm within subjects). Contrary to the predictions of the remapping hypothesis, cortical distances between activations to the two wedges were equally large for the blind-spot eye and fellow eye in areas V1 and V2/V3. Remapping therefore appears unlikely to account for perceptual filling-in at an early cortical level. 相似文献
18.
19.
Teles SA Martins RM Gomes SA Gaspar AM Araujo NM Souza KP Carneiro MA Yoshida CF 《Journal of medical virology》2002,68(1):41-49
A serological and molecular study of hepatitis B virus (HBV) infection was carried out in dialysis units in Central Brazil. Between 1995 and 1999, serum samples from all HBsAg-positive hemodialysis patients (n = 43) were tested for HBeAg/anti-HBe and subtyping by monoclonal ELISA. HBV DNA was detected by PCR and positive samples were genotyped by restriction fragment polymorphism pattern (RFLP) methodology. TheHBsAg prevalence declined in this population during the survey period (12-5.8%). HBeAg and anti-HBe were detected in 23 (53.5%) and 18 (41.9%) sera, respectively. Thirty-six samples could be HBsAg subtyped: 21 were subtype ayw(3), 14 belonged to adw(2) and one was identified as adw(4). HBV DNA was present in 30 serum samples. Of these, 20 (66.7%) were genotype D, 9 (30%) genotype A, and 1 (3.3%) genotype F. In addition, the RFLP pattern could be determined in samples from 18/20 genotype D patients: D3 (10 strains), D7 (7 strains) and D4 (1 strain); from 8/9 genotype A patients: A1 (6 strains) and A3 (2 strains); and from the patient infected with genotype F: F1. Patterns D3 and D7 were associated closely with HBV infection in the two largest hemodialysis units studied. These findings confirm the value of the RFLP method as an effective molecular epidemiological tool for elucidating HBV transmission in hemodialysis units. 相似文献
20.
M E Sherman M L Silverman K Balogh S S Tan 《Archives of pathology & laboratory medicine》1987,111(8):732-736
Multilocular renal cyst is a pathologically distinctive lesion of uncertain pathogenesis that usually presents as a large abdominal mass in male infants or middle-aged women. We performed detailed light and electron microscopic studies of three nephrectomy specimens that contained multilocular cysts and attempted to correlate their morphology with various theories of pathogenesis. In one of our cases, a microscopic focus of clear cells that resembled renal cell adenocarcinoma was observed in the wall of one locule. Although such a finding has been reported previously, the lack of well-documented cases with metastases suggests that the prognosis for patients with this lesion remains uniformly excellent. 相似文献