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91.
Song-Bin Chang Tae-Jin Yang Erwin Datema Joke van Vugt Ben Vosman Anja Kuipers Marie Meznikova Dóra Szinay René Klein Lankhorst Evert Jacobsen Hans de Jong 《Chromosome research》2008,16(7):919-933
This paper presents a bird’s-eye view of the major repeats and chromatin types of tomato. Using fluorescence in-situ hybridization (FISH) with Cot-1, Cot-10 and Cot-100 DNA as probes we mapped repetitive sequences of different complexity
on pachytene complements. Cot-100 was found to cover all heterochromatin regions, and could be used to identify repeat-rich
clones in BAC filter hybridization. Next we established the chromosomal locations of the tandem and dispersed repeats with
respect to euchromatin, nucleolar organizer regions (NORs), heterochromatin, and centromeres. The tomato genomic repeats TGRII
and TGRIII appeared to be major components of the pericentromeres, whereas the newly discovered TGRIV repeat was found mainly
in the structural centromeres. The highly methylated NOR of chromosome 2 is rich in [GACA]4, a microsatellite that also forms part of the pericentromeres, together with [GA]8, [GATA]4 and Ty1-copia. Based on the morphology of pachytene chromosomes and the distribution of repeats studied so far, we now propose six different
chromatin classes for tomato: (1) euchromatin, (2) chromomeres, (3) distal heterochromatin and interstitial heterochromatic
knobs, (4) pericentromere heterochromatin, (5) functional centromere heterochromatin and (6) nucleolar organizer region. 相似文献
92.
Kallikrein 4 expression is up-regulated in epithelial ovarian carcinoma cells in effusions 总被引:1,自引:0,他引:1
Davidson B Xi Z Klokk TI Tropé CG Dørum A Scheistrøen M Saatcioglu F 《American journal of clinical pathology》2005,123(3):360-368
We immunohistochemically analyzed kallikrein 4 protein (hK4) expression in patients with epithelial ovarian carcinoma (181 malignant effusions and 103 solid carcinoma lesions). Expression of hK4 was also studied in 32 effusions using immunoblotting. Carcinoma cells expressed hK4 in 144 (79.6%) of 181 effusions and 85 (82.5%) of 103 solid tumors. Expression was seen in 51% or more of tumor cells in 70 effusions but often was limited to 5% or fewer cells in solid tumors (P = .009, primary tumors vs effusions; P = .002, metastases vs effusions). Immunoblotting showed hK4 expression in 31 of 32 specimens. Stromal cell hK4 expression, seen in 48 (46.6%) of 103 lesions, was significantly higher in primary tumors than metastases (26/43 vs 22/60, P = .019). hK4 expression in tumor cells was significantly lower in International Federation of Gynecology and Obstetrics stage IV than stage III tumors (P = .004, all lesions; P = .012, primary tumors). hK4 expression in carcinoma cells was associated with longer overall survival (not significant; P = .14, peritoneal effusions). hK4 is expressed widely in ovarian carcinoma; levels in carcinoma cells are highest in effusions, which might be related to loss of stromal contribution and/or altered microenvironment. hK4 expression in carcinoma cells of effusions or solid tumors does not predict survival. 相似文献
93.
Lymphoepithelioma-like carcinoma of the bladder: three cases with clinicopathological and p53 protein expression study 总被引:12,自引:0,他引:12
Izquierdo-García FM García-Díez F Fernández I Pérez-Rosado A Sáez A Suárez-Vilela D Guerreiro-González R Benéitez-Alvarez M 《Virchows Archiv : an international journal of pathology》2004,444(5):420-425
Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma. 相似文献
94.
Variations in Helicobacter pylori lipopolysaccharide to evade the innate immune component surfactant protein D 总被引:2,自引:0,他引:2
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Khamri W Moran AP Worku ML Karim QN Walker MM Annuk H Ferris JA Appelmelk BJ Eggleton P Reid KB Thursz MR 《Infection and immunity》2005,73(11):7677-7686
Helicobacter pylori is a common and persistent human pathogen of the gastric mucosa. Surfactant protein D (SP-D), a component of innate immunity, is expressed in the human gastric mucosa and is capable of aggregating H. pylori. Wide variation in the SP-D binding affinity to H. pylori has been observed in clinical isolates and laboratory-adapted strains. The aim of this study was to reveal potential mechanisms responsible for evading SP-D binding and establishing persistent infection. An escape variant, J178V, was generated in vitro, and the lipopolysaccharide (LPS) structure of the variant was compared to that of the parental strain, J178. The genetic basis for structural variation was explored by sequencing LPS biosynthesis genes. SP-D binding to clinical isolates was demonstrated by fluorescence-activated cell sorter analyses. Here, we show that H. pylori evades SP-D binding through phase variation in lipopolysaccharide. This phenomenon is linked to changes in the fucosylation of the O chain, which was concomitant with slipped-strand mispairing in a poly(C) tract of the fucosyltransferase A (fucT1) gene. SP-D binding organisms are predominant in mucus in vivo (P = 0.02), suggesting that SP-D facilitates physical elimination. Phase variation to evade SP-D contributes to the persistence of this common gastric pathogen. 相似文献
95.
Development and application of a salmonid EST database and cDNA microarray: data mining and interspecific hybridization characteristics 总被引:10,自引:0,他引:10
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96.
Mansouri D Mrad K Sassi S Driss-Fourati M Abbes I Koubaa-Mahjoub W Hechiche M Ben Romdhane K 《Annales de pathologie》2004,24(2):179-182
Pseudo-angiomatous hyperplasia of mammary stroma (PASH) is a histopathological entity which is a microscopic fortuitous finding in mammary biopsies performed for different reasons. It may be symptomatic and appears then as a palpable lump. The term pseudo-angiomatous emphasizes the characteristic aspect of the stroma simulating a vascular tumor. We report a case of PASH in a 71 year-old woman who presented a recurring breast mass with rapid swelling of the mammary gland (70 x 60 x 20 cm) treated by mastectomy. PASH must be distinguished from a well-differentiated angiosarcoma. It is ruled out by immunohistochemistry. 相似文献
97.
Expression of CD44 in effusions of patients diagnosed with serous ovarian carcinoma – diagnostic and prognostic implications 总被引:2,自引:0,他引:2
Berner HS Davidson B Berner A Risberg B Kristensen GB Trope CG Van de Putte G Nesland JM 《Clinical & experimental metastasis》2000,18(2):197-202
CD44 is a family of cell adhesion molecules involved in a variety of cellular functions. The present study analysed the expression
of two CD44 isoforms in serous effusions of patients diagnosed with ovarian carcinoma and corresponding primary and metastatic
lesions. Fifty-eight effusions, 23 primary ovarian tumours, and 44 metastatic lesions were studied for protein expression
of CD44s and v3-10 using immunohistochemistry. Results were correlated with clinical parameters. CD44v3-10 was seen in carcinoma
cells in the majority of cases at all sites. Malignant effusions showed an up-regulation of CD44s compared to both primary
tumours and metastatic solid lesions. Mesothelial cells frequently expressed CD44s, but were rarely immunoreactive for v3-10.
CD44s immunoreactivity in cancer cells in effusions was significantly more often observed in patients with FIGO stage 3 than
in stage 4 patients (P = 0.045). Staining results did not correlate with age, effusion site, metastatic site, tumour grade or residual tumour mass
after initial surgery. Likewise, comparison of overall and disease-free survival with expression of the CD44 isoforms studied
did not reveal any statistically significant associations. The up-regulation in CD44 levels in effusions, primarily in stage
3 disease, suggests that adhesion of ovarian carcinoma cells to mesothelium may be regulated at the level of CD44s expression,
and provides further evidence of phenotypic alteration in the transition from primary tumour cell clones to effusions. The
similar expression profile of CD44 in carcinoma cells in peritoneal and pleural effusions supports our previous observations
and the hypothesis that carcinoma cells in peritoneal effusions are truly metastatic.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
98.
Constance Schrander-Stumpel Christine de Die-Smulders Marc de Krom Suzanne Schyns-Fleuren Ben Hamel Deni Jaeken Jean-Pierre Fryns 《Clinical genetics》1993,43(6):303-308
Schrander-Stumpel C, de Die-Smulders C, de Krom M, Schyns-Fleuren S, Hamel B, Jaeken D, Fryns J-P. Marden-Walker syndrome: case report, literature review and nosologic discussion.
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous. 相似文献
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous. 相似文献
99.
The effect of surface chemistry modification of titanium alloy on signalling pathways in human osteoblasts 总被引:2,自引:0,他引:2
Zreiqat H Valenzuela SM Nissan BB Roest R Knabe C Radlanski RJ Renz H Evans PJ 《Biomaterials》2005,26(36):7579-7586
Establishing and maintaining mature bone at the bone–device interface is critical to the long-term success of prosthesis. Poor cell adhesion to orthopaedic and dental implants results in implant failure. Considerable effort has been devoted to alter the surface characteristics of these biomaterials in order to improve the initial interlocking of the device and skeleton. We investigated the effect of surface chemistry modification of titanium alloy (Ti–6Al–4V) with zinc, magnesium or alkoxide-derived hydroxy carbonate apatite (CHAP) on the regulation of key intracellular signalling proteins in human bone-derived cells (HBDC) cultured on these modified Ti–6Al–4V surfaces. Western blotting demonstrated that modifying Ti–6Al–4V with CHAP or Mg results in modulation of key intracellular signalling proteins. We showed an enhanced activation of Shc, a common point of integration between integrins and the Ras/Mapkinase pathway. Mapkinase pathway was also upregulated, suggesting its role in mediating osteoblastic cell interactions with biomaterials. The signalling pathway involving c-fos (member of the activated protein-1) was also shown to be upregulated in osteoblasts cultured on the Mg and CHAP modified Ti–6Al–4V. Thus surface modification with CHAP or Mg may contribute to successful osteoblast function and differentiation at the skeletal tissue–device interface. 相似文献
100.
Requirements for the development of IL-4-producing T cells during intestinal nematode infections: what it takes to make a Th2 cell in vivo 总被引:1,自引:0,他引:1
Zhugong Liu Qian Liu John Pesce Robert M. Anthony Erika Lamb Jeannette Whitmire Hossein Hamed Motoko Morimoto Joseph F. Urban Jr William C. Gause 《Immunological reviews》2004,201(1):57-74
Summary: Components of the type 2 immune response may mediate host protection against both helminthic parasites and harmful allergic responses. A central player in this response is the T‐helper 2 (Th2) effector cell, which produces interleukin (IL)‐4, IL‐5, IL‐13, and other Th2 cytokines during the primary and memory response. Specific aspects of the parasite that trigger Th2‐cell differentiation are not yet defined. Furthermore, the cell types and cell surface and secreted molecules that provide the immune milieu required for the development of Th2 effector cells and also Th2 memory cells are not well understood. They will probably vary with the particular helminth or other antigen inducing the Th2 response. We have used third stage larvae of intestinal nematode parasites as adjuvants to promote naïve nonparasite antigen‐specific T cells to differentiate into Th2 cells. This model system avoids possible parasite antigen‐specific T‐cell clones or cross‐reactive memory T cells that may preferentially differentiate into Th2 effector cells during the course of infection and confound the stereotypical components of parasite‐induced Th2 cell differentiation. We have found that these parasites have a potent adjuvant effect and have used our model system to begin to investigate the events that lead to the development of polarized Th2 cells in vivo. 相似文献