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81.
不同补锌方法对儿童免疫功能的影响 总被引:2,自引:0,他引:2
研究不同补锌方法(补锌,补充微量营养素,补充锌加微量营养素)改善缺锌儿童免疫功能的作用,结果显示:实验10wk后,三个实验组缺锌儿童血清锌浓度明显升高,同时淋巴细胞刺激指数明显高于对照组,流式细胞仪检测细胞周期显示对照组G0/G1期细胞增多,而实验组S+G0/G1期细胞增多,细胞处于增殖活化状态。三组中又以锌+微量营养素作用效果最好。表明:锌和微量营养素单独使用均增强缺锌儿童的免疫功能,但锌和微量 相似文献
82.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
83.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
84.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
85.
The biocompatibility and biofilm resistance of implant coatings based on hydrophilic polymer brushes conjugated with antimicrobial peptides 总被引:1,自引:0,他引:1
Gao G Lange D Hilpert K Kindrachuk J Zou Y Cheng JT Kazemzadeh-Narbat M Yu K Wang R Straus SK Brooks DE Chew BH Hancock RE Kizhakkedathu JN 《Biomaterials》2011,32(16):3899-3909
Bacterial colonization on implant surfaces and subsequent infections are one of the most common reasons for the failure of many indwelling devices. Several approaches including antimicrobial and antibiotic-eluting coatings on implants have been attempted; however, none of these approaches succeed in vivo. Here we report a polymer brush based implant coating that is non-toxic, antimicrobial and biofilm resistant. These coating consists of covalently grafted hydrophilic polymer chains conjugated with an optimized series of antimicrobial peptides (AMPs). These tethered AMPs maintained excellent broad spectrum antimicrobial activity in vitro and in vivo. We found that this specially structured robust coating was extremely effective in resisting biofilm formation, and that the biofilm resistance depended on the nature of conjugated peptides. The coating had no toxicity to osteoblast-like cells and showed insignificant platelet activation and adhesion, and complement activation in human blood. Since such coatings can be applied to most currently used implant surfaces, our approach has significant potential for the development of infection-resistant implants. 相似文献
86.
Kaylah Teresa De Silva Wendell David Cockshaw Imogen C. Rehm Nicola Hancock 《Clinical psychology & psychotherapy》2021,28(5):1135-1145
The Recovery Assessment Scale-Domains and Stages (RAS-DS) is a 38-item self-report instrument measuring recovery from serious mental illness. We explored the suitability of the RAS-DS for individuals with anxiety disorders. A parsimonious short form of the scale was developed. Participants with anxiety disorder symptoms (N = 295) completed the RAS-DS, DASS-21 and GAD-7. Confirmatory factor analysis supported the expected four-factor structure. Associations with related scales exhibited the expected pattern supporting construct validity in this population. The Recovery Assessment Scale-Short Form (RAS-SF) was derived by inspection of factor loadings and modification indices, yielding a 20-item scale with five items per subscale. Strong correlations between subscales confirmed the total score represented a valid overarching measure of recovery. The present study indicates that recovery is pertinent to individuals with anxiety disorders. Development of the short-form RAS-SF affords opportunity for routine measurement of recovery in populations with anxiety and other high prevalence conditions. 相似文献
87.
Delayed and deficient dermal maturation in mice lacking the CXCR3 ELR-negative CXC chemokine receptor 下载免费PDF全文
Yates CC Whaley D Kulasekeran P Hancock WW Lu B Bodnar R Newsome J Hebda PA Wells A 《The American journal of pathology》2007,171(2):484-495
Replacement of wounded skin requires the initially florid cellular response to abate and even regress as the dermal layer returns to a relatively paucicellular state. The signals that direct this "stop and return" process have yet to be deciphered. CXCR3 chemokine receptor and its ligand CXCL11/IP-9/I-TAC are expressed by basal keratinocytes and CXCL10/IP-10 by keratinocytes and endothelial cells during wound healing in mice and humans. In vitro, these ligands limit motility in dermal fibroblasts and endothelial cells. To examine whether this signaling pathway contributes to wound healing in vivo, full-thickness excisional wounds were created on CXCR3 wild-type (+/+) or knockout (-/-) mice. Even at 90 days, long after wound closure, wounds in the CXCR3(-/-) mice remained hypercellular and presented immature matrix components. The CXCR3(-/-) mice also presented poor remodeling and reorganization of collagen, which resulted in a weakened healed dermis. This in vivo model substantiates our in vitro findings that CXCR3 signaling is necessary for inhibition of fibroblast and endothelial cell migration and subsequent redifferentiation of the fibroblasts to a contractile state. These studies establish a pathophysiologic role for CXCR3 and its ligand during wound repair. 相似文献
88.
J.A. Hancock 《Cognitive neuropsychiatry》2013,18(3):213-220
There are two currently influential views regarding the link between cognitive distortions and depression. The first states that depressed individuals perceive the world and themselves with a strong negative bias or distortion, and that mentally healthy individuals perceive the word with relative accuracy. The second “depressive realism” camp argues that healthy individuals are positively biased and the depressed are relatively unbiased and hence, more realistic. In the present investigation, subjects suffering from major depression, subjects recovered from major depression, and a group of healthy controls were examined with regard to their confidence in answering each of 99 general knowledge questions. Confidence ratings were analysed separately according to correct or incorrect responses. There were no significant differences in performance (i.e. accuracy of answer between the three groups). When answering correctly, depressed subjects were significantly less confident than healthy control subjects. On answering incorrectly, none of the three groups were significantly different in their confidence ratings. These findings support the cognitive distortion view of depression and provide no evidence of “depressive realism”. 相似文献
89.
Rottman JB Slavin AJ Silva R Weiner HL Gerard CG Hancock WW 《European journal of immunology》2000,30(8):2372-2377
We have shown that macrophages and microglia present within demyelinating plaques of patients with multiple sclerosis (MS) are immunoreactive for the chemokine receptor CCR1 and its ligand, macrophage inflammatory protein-1alpha. To test the importance of CCR1 to the pathogenesis of MS, we studied the progression of experimental allergic encephalomyelitis (EAE) in CCR1(+/+) vs. CCR1(-/-) mice. After immunization with myelin oligodendrocyte glycoprotein (MOG) 35-55 peptide, nearly all CCR1(+/+) mice developed EAE (95% incidence, severity 2.5+/-0.1), whereas CCR1(-/-) mice had less severe disease (55% incidence, p<0.001; severity 1. 2+/-0.2, p<0.001). CCR1(+/+) mice showed elevated brain mRNA for the chemokines immune protein (IP)-10, RANTES and monocyte chemoattractant protein-1 prior to disease onset, whereas only IP-10 mRNA was elevated in CCR1(-/-) mice. Both groups of mice had comparable in vitro lymphocyte proliferation and cytokine production upon stimulation with MOG peptide, and similar cutaneous hypersensitivity responses to 2,4-dinitrofluorobenzene, suggesting that CCR1(-/-) mice were not systemically immunosuppressed. These data demonstrate that deletion of a chemokine receptor is at least partially protective in EAE, and suggest that targeting of CCR1 may be of therapeutic significance clinically. 相似文献
90.
Langerhans cells, important participants in the cutaneous cellular immune response, are markedly diminished in skin of patients undergoing allogeneic bone marrow transplantation during the first 4 weeks after this procedure. To determine the mechanism responsible for the subsequent repopulation of these cells, the authors studied the immunophenotypic and morphologic profiles of sequential skin biopsies during the posttransplantation period. Cells with surface antigens of monocytes/macrophages within the superficial dermis were gradually replaced by dermal and epidermal dendritic cells exhibiting coexpression of monocyte/macrophage and Langerhans cell surface antigens. Ultrastructural examination revealed that many of these cells contained both prominent phagolysosomes and Birbeck granules. Antigenically and structurally mature Langerhans cells were observed within the epidermis by the end of the second month after transplantation. Phenotypic transformation of phagocytic dermal macrophages to Langerhans cells appears to represent a mechanism for repopulation of Langerhans cells during the period of immunologic reconstitution in this patient population. 相似文献