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71.
Filho OG Gordan AN Mello Rde A Neto CS Heinke T 《International journal of surgical pathology》2004,12(2):151-153
Hamartomas were first described by Albrecht in 1904, who defined them as tumor-like malformations in which there was abnormal blending of the normal components of an organ. The myoid hamartoma is a rare benign lesion of the breast and has an uncertain origin, possibly in the walls of the blood vessels, muscularis mammillae of the areolae, and mainly in myoepithelium. We report 3 cases of myoid hamartomas of the breast, with the clinical, radiologic, and histopathological findings, and review the literature. The 3 lesions showed normal breast ducts and lobules, entrapped by a muscular stroma and some foci of mature adipose tissue. The muscular origin of part of the stroma was confirmed by strong reactiveness with smooth-muscle actin. 相似文献
72.
Wong N Hui AB Fan B Lo KW Pang E Leung SF Huang DP Johnson PJ 《Cancer Genetics and Cytogenetics》2003,140(2):124-132
Nasopharyngeal carcinoma (NPC) cell lines and xenografts represent valuable models for functional and therapeutic studies on this common malignancy in Southeast Asia. The karyotypic information in most NPC cell lines and xenografts, however, remains largely unclear to date. We have characterized the chromosomal aberrations in six commonly used human NPC cell lines and xenografts using the molecular cytogenetic technique of comparative genomic hybridization (CGH). Genomic imbalances identified in cell lines were further correlated with structural abnormalities indicated from spectral karyotyping (SKY) analysis. CGH revealed consistent overrepresentations of 8q (six out of six cases) with a smallest overlapping region identified on 8q21.1q22. Other common gains included 7p (4/6 cases), 7q (4/6 cases), 12q (4/6), and 20q (4/6 cases), where minimal overlapping regions were suggested on 7p15p14, 7q11.2q21, and 12q22q24.1. Common losses were detected on 3p12p21 (4/6 cases) and 11q14qter (4/6 cases). Although SKY analysis on cell lines revealed predominantly unbalanced rearrangements, reciprocal translocations that involved chromosome 2 [i.e., t(1;2), t(2;3), and t(2;4)] were suggested. Furthermore, SKY examination illustrated additional breakpoints on a number of apparently balanced chromosomes. These breakpoints included 3p21, 3q26, 5q31, 6p21.1p25, 7p14p22, and 8q22. Our finding of regional gains and losses and breakpoints represents information that may contribute to NPC studies in vitro. 相似文献
73.
Lovering Ruth; Middleton-Price Helen R.; O'Reilly Marie-Anne J.; Genet Sally A.; Parkar Mohammed; Sweatman Angela K.; Bradley Linda D.; Alterman Lesley A.; Malcolm Sue; Morgan Gareth; Levinsky Roland J.; Kinnon Christine 《Human molecular genetics》1993,2(2):139-141
Genetic linkage analysis has been instrumental in mapping thegene for X-linked agammaglobulinemia (XLA) to the proximal longarm of the human X chromosome, to Xq22. Due to the relativerarity of this disease the localization of the gene within Xq22has remained imprecise. We have investigated twenty-nine familiesaffected by XLA and have found no recombinants with the DXS178locus in over 30 informative meioses. DXS178 is now the mostreliable and informative locus for use in pre-natal diagnosisand carrier detection of XLA. In addition, we have identifiednew closely linked proximal and distal flanking markers forXLA, DXS442 and DXS101, respectively. These loci are separatedby 2cM, considerably reducing the extent of DNA within whichthe XLA locus can be contained. This will open up the way formore directed positional cloning efforts for the isolation ofthe XLA gene. 相似文献
74.
Candida albicans expresses a focal adhesion kinase-like protein that undergoes increased tyrosine phosphorylation upon yeast cell adhesion to vitronectin and the EA.hy 926 human endothelial cell line 下载免费PDF全文
Santoni G Lucciarini R Amantini C Jacobelli J Spreghini E Ballarini P Piccoli M Gismondi A 《Infection and immunity》2002,70(7):3804-3815
The signaling pathways triggered by adherence of Candida albicans to the host cells or extracellular matrix are poorly understood. We provide here evidence in C. albicans yeasts of a p105 focal adhesion kinase (Fak)-like protein (that we termed CaFak), antigenically related to the vertebrate p125Fak, and its involvement in integrin-like-mediated fungus adhesion to vitronectin (VN) and EA.hy 926 human endothelial cell line. Biochemical analysis with different anti-chicken Fak antibodies identified CaFak as a 105-kDa protein and immunofluorescence and cytofluorimetric analysis on permeabilized cells specifically stain C. albicans yeasts; moreover, confocal microscopy evidences CaFak as a cytosolic protein that colocalizes on the membrane with the integrin-like VN receptors upon yeast adhesion to VN. The protein tyrosine kinase (PTK) inhibitors genistein and herbimycin A strongly inhibited C. albicans yeast adhesion to VN and EA.hy 926 endothelial cells. Moreover, engagement of alpha v beta 3 and alpha v beta 5 integrin-like on C. albicans either by specific monoclonal antibodies or upon adhesion to VN or EA.hy 926 endothelial cells stimulates CaFak tyrosine phosphorylation that is blocked by PTK inhibitor. A role for CaFak in C. albicans yeast adhesion was also supported by the failure of VN to stimulate its tyrosine phosphorylation in a C. albicans mutant showing normal levels of CaFak and VNR-like integrins but displaying reduced adhesiveness to VN and EA.hy 926 endothelial cells. Our results suggest that C. albicans Fak-like protein is involved in the control of yeast cell adhesion to VN and endothelial cells. 相似文献
75.
Multiple pathways of cell invasion are regulated by multiple families of serine proteases 总被引:5,自引:0,他引:5
Del Rosso M Fibbi G Pucci M D'Alessio S Del Rosso A Magnelli L Chiarugi V 《Clinical & experimental metastasis》2002,19(3):193-207
The complex process of tumor invasion requires the coordinated expression and activity of cell-substratum adhesive interactions
and of cell-associated protease systems, which destroy the extracellular matrix (ECM), in order to enable the invading cells
to simultaneously grip and destroy the anatomical barriers that control cell spreading. A number of data indicate that such
a `grip and go' process may be performed by an enlarging series of cell membrane-associated serine proteases and serine protease
receptors, which provide the invasive cells with a functional unit (the protease and its receptor), able to mediate cell-substratum
adhesion through specific receptor domains, to proteolytically degrade ECM and to deliver into the cell signals that up-regulate
the expression either of the protease/receptor complex, or of other adhesion molecules, such as integrins. There is evidence
that some proteases and protease receptor expression are under the control of tumor hypoxia, which is the result of an imbalance
in oxygen supply and demand. The urokinase-type plasminogen activator (u-PA) receptor (u-PAR) is under hypoxic control and
cooperates with other serine proteases of the blood coagulation pathways that may extravasate in the tumor milieu as a result
of hypoxia-simulated increase of vessel permeability. Other serine proteases and their receptors cooperate with the cell-associated
fibrinolytic system to promote cell invasion. Among these, tissue factor and its ligand coagulation factor VII, thrombin and
its protease-activated receptors, and type II trans-membrane serine proteases seem to play a crucial role. This Review takes
into consideration the complex scenario of the single serine proteases and related receptors that are involved in cell invasion,
as well as the protease receptor/adhesion molecule interplay which is necessary to focus the cell surface-driven proteolysis
where adhesion provides a grip to the invading cell.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
76.
Paradiso A Abatangelo M Piepoli S Tommasi S Xu JM Caponio MA Marzullo F D'Auria C Achille G Grammatica L 《Cancer Genetics and Cytogenetics》2002,132(2):141-144
Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found. 相似文献
77.
Kimura T Nakamori M Lueck JD Pouliquin P Aoike F Fujimura H Dirksen RT Takahashi MP Dulhunty AF Sakoda S 《Human molecular genetics》2005,14(15):2189-2200
Myotonic dystrophy type 1 (DM1) is a debilitating multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant splicing of several genes has been reported to contribute to some symptoms of DM1, but the cause of muscle weakness in DM1 and elevated Ca2+ concentrations in cultured DM muscle cells is unknown. Here, we investigated the alternative splicing of mRNAs of two major proteins of the sarcoplasmic reticulum, the ryanodine receptor 1 (RyR1) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) 1 or 2. The fetal variants, ASI(-) of RyR1 which lacks residue 3481-3485, and SERCA1b which differs at the C-terminal were significantly increased in skeletal muscles from DM1 patients and the transgenic mouse model of DM1 (HSA(LR)). In addition, a novel variant of SERCA2 was significantly decreased in DM1 patients. The total amount of mRNA for RyR1, SERCA1 and SERCA2 in DM1 and the expression levels of their proteins in HSA(LR) mice were not significantly different. However, heterologous expression of ASI(-) in cultured cells showed decreased affinity for [3H]ryanodine but similar Ca2+ dependency, and decreased channel activity in single-channel recording when compared with wild-type (WT) RyR1. In support of this, RyR1-knockout myotubes expressing ASI(-) exhibited a decreased incidence of Ca2+ oscillations during caffeine exposure compared with that observed for myotubes expressing WT-RyR1. We suggest that aberrant splicing of RyR1 and SERCA1 mRNAs might contribute to impaired Ca2+ homeostasis in DM1 muscle. 相似文献
78.
Alkuraya FS Lin AE Irons MB Kimonis VE 《American journal of medical genetics. Part A》2005,(2):226-230
Fryns syndrome is an autosomal recessive multiple congenital anomaly/mental retardation syndrome characterized by coarse face, distal limb hypoplasia, and diaphragmatic anomalies. We describe a newborn girl with Fryns syndrome and Hirschsprung disease, an association that has been reported in five previous cases. These patients support the hypothesis that the neural crest plays a role in the pathogenesis of Fryns syndrome. Clinically asymptomatic or subtle anomalies that are in the spectrum of neural crest maldevelopment should be sought in all patients with Fryns syndrome including stillbirths, neonatal deaths, as well as long-term survivors. We suspect that the clinical observation about Hirschsprung disease and Fryns syndrome may provide insight into its molecular mechanisms and candidate genes. 相似文献
79.
Regan N Theiler Angela M Caliendo Sabine Pargman B Denise Raynor Sarah Berga Melissa McPheeters Denise J Jamieson 《Journal of clinical virology》2006,37(4):313-316
BACKGROUND: Cytomegalovirus (CMV) infection, which is the most common congenitally transmitted infection, affects approximately 1% of neonates worldwide. Despite its prevalence, no convenient screening test for neonatal CMV infection has been implemented. OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and yield of screening umbilical cord blood for CMV DNA emiaby quantitative PCR. STUDY DESIGN: Umbilical cord blood was tested for CMV DNAemia using a commercial quantitative PCR assay. Maternal CMV serostatus at the time of delivery was assessed by testing for CMV IgG and IgM antibodies in serum. CONCLUSIONS: Screening for congenital CMV infection with PCR is easily incorporated into routine labor and delivery care using discarded cord blood specimens to identify neonates whose infection is otherwise undiagnosed. Among 433 infants tested, two (0.5%) had DNAemia detected in cord blood, one of whom was symptomatic, and both of whose mothers were CMV IgG positive and IgM negative. Viremic neonates identified by screening with PCR may be at high risk of developing long-term neurological complications of CMV infection and cannot reliably be identified using clinical presentation or maternal serology. Because of its convenience, cord blood CMV screening with PCR should be further investigated for incorporation into neonatal screening protocols. 相似文献
80.
Alexander Rodewald Rainer Pankau Angela Gosch Armin Wessel 《American journal of medical genetics. Part A》1994,53(3):227-235
The dermatoglyphic patterns of fingertips and palms of 115 patients with Williams-Beuren syndrome (WBS) were analysed and compared with the data from 199 control individuals from Germany. The following combination of dermatoglyphic patterns appears to be characteristic to WBS: an excess of whorls on all fingertips; high termination values of the main lines D, B, and A; frequent absence of C triradius (C°); high frequencies of ulnar loops on the hypothenar and distal loops on the 2nd, 3rd, and 4th inter digital areas, of distal axial triradii t", and of abnormal palmar creases such as simian crease and Sydney lines. The combination of fingertip and palmar patterns expressed by a “Log.Score-Index,” provides a high degree of discrimination between the WBS patients (92%) and the control group (88%). A “phantom picture” for WBS was constructed, which can be used for its diagnosis. © 1994 Wiley-Liss, Inc. 相似文献