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81.
J. Allan Tucker 《Ultrastructural pathology》1993,17(3):279-286
Classically, ultrastructural examination of alveolar soft part sarcoma reveals large, dramatic, rhomboid to needlelike crystals with a characteristic substructure. In this study of four cases of alveolar soft part sarcoma, only two exhibited large crystals, which were rare. All four cases, however, exhibited round, electron-dense granules, and in the two cases without large crystals these granules rarely exhibited elongation with the characteristic substructure of alveolar soft part sarcoma that permits definitive diagnosis. Two of these cases had been previously studied at other institutions, where crystals were not identified ultrastructurally and electron microscopy was considered noncontributory. Large crystals, then, may be rare or absent in alveolar soft part sarcoma. Careful search may be necessary to find granules with the characteristic periodic substructure. 相似文献
82.
Dr. G. S. Tucker D. I. Hamasaki A. Labbie J. Muroff 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1979,37(3):459-474
Summary The postnatal development of the photoreceptor of the cat was studied using physiological and anatomical methods. The late receptor potential (LRP) was recorded in vitro and the threshold and maximum amplitude determined. The same specimens used in the electrophysiological studies were then prepared for microscopy, and rod cell outer and inner segment length and diameter, photoreceptor density, and inter-receptor distance were determined. A small LRP was first recorded at 9–10 days, but only at very high stimulus intensities. Thereafter, there was a rapid decrease in the threshold and an increase in the amplitude of the LRP. The threshold reached adult values at 17–18 days, while the amplitude of the LRP was adultlike at 23–26 days. Of the anatomical parameters examined, inter-receptor spacing and rod cell diameters seem to be most clearly associated, respectively, with the attainment of adult LRP threshold and amplitude. Outer segment length was adult-like at 35–43 days of age and thus postdated physiological maturity of the photoreceptor. These observations suggest that the surface area of the rod cell outer segment tips is more critical in the development of the adult LRP than is the number of discs in the outer segment. In addition, changes over time in the mean diameter and length of rod cell inner segments follows the pattern of ontogenetic changes in LRP amplitude. These findings imply a close relationship during ontogeny between the metabolic functions of the inner segment and phototransduction at the outer segment disc.This study was supported by the Florida Lions Eye Bank (GST) and by a grant, 2-RO1-EY00376-08, from the National Eye Institute, National Institutes of Health, Bethesda, Maryland (DIH)Andrew Labbie and Joseph Muroff were participants in the Community Laboratory Research Programm sponsored by the Dade County Public School System, Miami, Florida 相似文献
83.
Natalie M. Gallant Kathryn E. Singh Candida Brown Virginia Kimonis Eric A. Muller II 《American journal of medical genetics. Part A》2019,179(3):498-502
ALG11‐Congenital Disorder of Glycosylation (ALG11‐CDG, also known as congenital disorder of glycosylation type Ip) is an inherited inborn error of metabolism due to abnormal protein and lipid glycosylation. We describe two unrelated patients with ALG11‐CDG due to novel mutations, review the literature of previously described affected individuals, and further expand the clinical phenotype. Both affected individuals reported here had severe psychomotor disabilities and epilepsy. Their fibroblasts synthesized truncated precursor glycan structures, consistent with ALG11‐CDG, while also showing hypoglycosylation of a novel biomarker, GP130. Surprisingly, one patient presented with normal transferrin glycosylation profile, a feature that has not been reported previously in patients with ALG11‐CDG. Together, our data expand the clinical and mutational spectrum of ALG11‐CDG. 相似文献
84.
Maria C Nascimento Natalie Wilder Claudio S Pannuti Helen A Weiss Philippe Mayaud 《Journal of clinical virology》2005,33(1):52-59
BACKGROUND: Kaposi's sarcoma (KS) is caused by Kaposi's sarcoma associated herpesvirus (KSHV/HHV-8), the eighth Herpesvirus found to infect humans. The molecular epidemiology of KSHV is related closely to ethnicity and geographical location of studied populations. There is little epidemiological and molecular information about KSHV strains circulating in Brazil. OBJECTIVES: To characterize KSHV strains isolated from AIDS patients with Kaposi's sarcoma (AIDS-KS) in Sao Paulo, Brazil, and to examine associations between KSHV subtypes, ethnicity and HIV risk categories. METHODS: AIDS-KS patients were recruited consecutively at the largest AIDS reference hospital in Sao Paulo. Fragments (420 bp) of the VR1 and VR2 regions of KSHV open reading frame (ORF) K1 were amplified by nested PCR and sequenced directly. RESULTS: We analysed 37 samples from 33 patients, and found subtypes A-C in 48%, 21% and 30% of patients respectively, including two patients infected with subtype A5, a first report from Brazil. Sexual orientation was associated with subtype: 12/14 (86%) patients with subtype A were male homo/bisexual, compared with 3/8 (38%) among patients infected with subtype C (P = 0.05). A higher proportion of male patients with subtype C were of Caucasian origin (7/8 (87%)), compared with 7/16 (44%) among male patients with subtype A (P = 0.08). CONCLUSIONS: This first detailed report of KSHV subtypes among AIDS-KS patients in Brazil reports the first isolation of KSHV subtype A5 in this country, and suggests KSHV strain transmission between different ethnic groups, and association of specific strains with sexual orientation. 相似文献
85.
Apoptotic body engulfment by a human stellate cell line is profibrogenic 总被引:22,自引:0,他引:22
Canbay A Taimr P Torok N Higuchi H Friedman S Gores GJ 《Laboratory investigation; a journal of technical methods and pathology》2003,83(5):655-663
Hepatocyte apoptosis and stellate cell activation are both features of chronic liver diseases, but a relationship between these events has not been explored. In macrophages, engulfment of apoptotic bodies induces expression of transforming growth factor-beta (TGF-beta), a profibrogenic cytokine. We examined whether a similar response occurs in stellate cells. Fluorescently labeled hepatocyte apoptotic bodies were added to cultures of primary and immortalized human stellate cells. Stellate cells, but not hepatocytes, readily engulfed apoptotic bodies in a time-dependent manner as assessed by confocal microscopy. The activation of primary and immortalized human stellate cells after incubation with apoptotic bodies, as well as their fibrogenic activity, was indicated by an increase in alpha-smooth muscle actin (primary cells), TGF-beta1, and collagen alpha1(I) mRNA (primary and immortalized cells). The profibrogenic response was dependent upon apoptotic body engulfment, because nocodazole, a microtubule-inhibiting agent, blocked both the engulfment and the increase of TGF-beta1 and collagen alpha1(I) mRNA. As described in primary rodent stellate cells, up-regulation of collagen alpha1(I) mRNA was inhibited by a PI-3K inhibitor (LY294002) and a p38 mitogen-activated protein kinase inhibitor (SB203580) in LX-1 cells. In conclusion, these data support a model in which engulfment of hepatocyte apoptotic bodies by stellate cells leads to a fibrogenic response by eliciting a kinase-signaling pathway. 相似文献
86.
Targeted recruitment of a histone H4-specific methyltransferase by the transcription factor YY1 总被引:3,自引:0,他引:3
Rezai-Zadeh N Zhang X Namour F Fejer G Wen YD Yao YL Gyory I Wright K Seto E 《Genes & development》2003,17(8):1019-1029
87.
Adjacent-2 disjunction of a maternal t(9;22) leading to duplication 9pter----q22 and deficiency of 22pter----q11.2 总被引:2,自引:0,他引:2
E K Pivnick R S Wilroy J B Summitt B Tucker H G Herrod A T Tharapel 《American journal of medical genetics》1990,37(1):92-96
The proposita presented at birth with multiple congenital anomalies including craniofacial anomalies, bilateral cleft lip and palate, abnormalities of the urogenital system, talipes equinovarus, and the DiGeorge sequence. Cytogenetic investigation showed a 46,XX,-22,+der(9)t(9;22)(q22;q11.2) karyotype. The mother, maternal uncle, and maternal grandmother of the infant are carriers of a reciprocal balanced translocation involving chromosomes 9 and 22 at regions q22 and q11.2, respectively. The unbalanced karyotype seen in the proposita arose due to an adjacent-2 disjunction of the quadrivalent in the mother. Prenatal diagnosis of the second pregnancy of this woman showed a similar karyotype. Review of the literature shows that adjacent-2 disjunction may occur preferentially when certain chromosomes are involved in translocations. 相似文献
88.
For some time, clinical reports have described impairment of affective and cognitive functions in iron deficient persons. Recent studies suggest that both brain biochemistry and cognitive performance capacity may be disrupted by inadequate intake of dietary iron, but the relationship of the possible neurophysiological effects to psychological ones is unclear. To examine the relationship of iron status to simultaneous measures of cortical activation and cognitive performance, 8 channels of electroencephalographic (EEG) data were recorded during a resting period and during the performance of several cognitive tasks in two groups of men. The EEG data were spectrally analyzed, and measures of total power and frequency of peak power in each of several bands of the power spectrum for each channel were used as predictors in multiple regression analyses with serum iron and serum ferritin as alternative criteria. Measures of power in the delta frequency in the resting period appeared relevant to iron status in both groups, perhaps indicating alertness or arousal level. Consistently in these regressions, the asymmetry of the EEG appeared relevant to iron and ferritin. These findings suggest that the combination of EEG and performance measures may help characterize the neuropsychological effects of trace element nutrition. 相似文献
89.
Construction of an antigenic map for human B-cell precursors 总被引:5,自引:0,他引:5
The purpose of this study was to evaluate the binding of a panel of monoclonal antibodies to human pre-B cells present in fetal, pediatric, and adult bone marrow. The antibodies included BA-1, BA-2, BA-3 (anti-CALLA), anti-B1, L243 (anti-HLA-DR), and T101. Binding of the monoclonal antibodies to pre-B cells was evaluated at the single-cell level by double fluorochrome analysis. Percentages of BA-1+ and anti-B1+ pre-B cells were independent of age group. BA-1 bound to approximately 80% of fetal, pediatric, and adult bone marrow pre-B cells, whereas anti-B1 bound to approximately 50%. BA-2 bound to 55% of fetal pre-B cells, but this percentage decreased to 32% in pediatric and 16% in adult bone marrow. CALLA was expressed on less than 10% of fetal, pediatric, and adult bone marrow pre-B cells, and HLA-DR was expressed on greater than 95% of fetal, pediatric, and adult pre-B cells. Although T101 (an anti-T-cell monoclonal antibody) did not bind to pre-B cells, it did bind to approximately 25% of the sIgM+ cells in fetal bone marrow. These results suggest a predominant phenotype of L243 (anti-HLA-DR)+, BA-1+, BA-3 (anti-CALLA)-, T101- for the human pre-B cell while phenotypic heterogeneity exists for anti-B1 and BA-2. 相似文献
90.
Francesca Fernandez Robert P Curtain Natalie J Colson Micky Ovcaric John MacMillan Lyn R Griffiths 《BMC medical genetics》2007,8(1):57