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排序方式: 共有592条查询结果,搜索用时 28 毫秒
1.
Infantile myofibromatosis is an uncommon, benign, probably hamartomatous proliferation of myofibroblasts. Its growth is typically self-limiting but histologically it can simulate a sarcoma. A rare case of solitary infantile myofibromatosis presenting as an intraoral mass in a 10-year-old girl is reported. 相似文献
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Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro 总被引:1,自引:0,他引:1
The study investigates the correlation between oocyte maturity and
fertilization and a variety of hormonal parameters in follicular fluid and
ovarian granulosa cells. A methodology for purification of granulosa cells
from contaminating blood cells is also established. A total of 63
follicular aspirates were collected at oocyte retrieval from 30 women
superovulated using the long luteinizing hormone- releasing hormone (LHRH
analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone,
testosterone and human chorionic gonadotrophin (HCG) were quantified in
follicular fluid and granulosa cells were immunostained for human chorionic
gonadotrophin. Immunopurification of granulosa cells from contaminating
blood cells was performed. HCG in follicular fluid was significantly high
in follicles yielding immature (grade 3) oocytes (P=0.002); there was no
correlation with fertilization. Aspirates from follicles containing mature
(grade 1) oocytes and oocytes that subsequently fertilized had
significantly more granulosa cells immunobound to HCG (P < 0.001,
P=0.02). Moreover, the immunomagnetic purification technique provided
>98% pure population of granulosa cells. The data demonstrate that HCG
in follicular fluid and on granulosa cells may help to predict oocyte
maturity and fertilization. Furthermore, immunomagnetic beads provide a
reliable procedure for the purification of ovarian granulosa cells.
相似文献
5.
Burwinkel B; Maichele AJ; Aagenaes O; Bakker HD; Lerner A; Shin YS; Strachan JA; Kilimann MW 《Human molecular genetics》1997,6(7):1109-1115
Glycogen storage disease due to phosphorylase kinase deficiency occurs in
several variants that differ in mode of inheritance and tissue-
specificity. This heterogeneity is suspected to be largely due to mutations
affecting different subunits and isoforms of phosphorylase kinase. The gene
of the ubiquitously expressed beta subunit, PHKB, was a candidate for
involvement in autosomally transmitted phosphorylase kinase deficiency of
liver and muscle. To identify such mutations, the complete PHKB coding
sequence was amplified by RT-PCR of RNA isolated from blood samples of
patients and analyzed by direct sequencing of PCR products. The
characterization of mutations was complemented by PCR of genomic DNA. In
one female and four male patients, we identified five independent nonsense
mutations (Y418ter; R428ter; Y974H+E975ter; Q656ter in two cases), one
single-base insertion in codon N421, one splice-site mutation affecting
exon 31, and a large deletion involving the loss of exon 8. Although these
severe translation-disrupting mutations occur in constitutively expressed
sequences of the only known beta subunit gene of phosphorylase kinase,
PHKB, they are associated with a surprisingly mild clinical phenotype,
affecting virtually only the liver, and relatively high residual enzyme
activity of approximately 10%.
相似文献
6.
Active detachment involves inhibition of cell-matrix contacts of malignant melanoma cells by secretion of melanoma inhibitory activity 总被引:3,自引:0,他引:3
Bosserhoff AK Stoll R Sleeman JP Bataille F Buettner R Holak TA 《Laboratory investigation; a journal of technical methods and pathology》2003,83(11):1583-1594
Melanoma inhibitory activity (MIA) has been identified as a small protein secreted from malignant melanoma cells. Recent results revealed a direct interaction of MIA and epitopes within extracellular matrix proteins including fibronectin. The aim of this study was to analyze functional consequences mediated by this interaction. Here we show that MIA interferes specifically with attachment of melanoma cells to fibronectin, a phenomenon we refer to as active detachment. Antibodies inhibiting binding of alpha4beta1 and alpha5beta1 integrins to fibronectin cross-react specifically with MIA, suggesting that MIA shares significant structural homology with the binding pockets of these integrins and thereby masks the respective epitopes on extracellular matrix molecules. Several peptides derived from fibronectin and from a phage display screening were tested with respect to a potential MIA-inhibitory effect. In vitro tests identified two peptides affecting MIA function; both inhibited growth of melanoma metastases in vivo. In summary, we conclude that MIA may play a role in tumor progression and spread of malignant melanomas via mediating active detachment of cells from extracellular matrix molecules within their local milieu. Further, our results suggest that inhibiting MIA functions in vivo may provide a novel therapeutic strategy for metastatic melanoma disease. 相似文献
7.
Delivery of a hammerhead ribozyme specifically down-regulates the production of fibrillin-1 by cultured dermal fibroblasts 总被引:4,自引:1,他引:4
Kilpatrick MW; Phylactou LA; Godfrey M; Wu CH; Wu GY; Tsipouras P 《Human molecular genetics》1996,5(12):1939-1944
The hammerhead ribozyme is a small catalytic RNA molecule. Potential
hammerhead ribozymes that possess a catalytic domain and flanking sequence
complementary to a target mRNA can cleave in trans at a putative cleavage
site within the target molecule. We have investigated the potential of
hammerhead ribozymes to down-regulate the product of the fibrillin-1 gene
(FBN1). Fibrillin is a 347 kDa glycoprotein that is a major constituent of
the elastin-associated microfibrils. Mutations in the FBN1 gene are
responsible for Marfan syndrome (MFS), a common systemic disorder of the
connective tissue. Many FBN1 mutations responsible for MFS appear to act in
a dominant-negative fashion, raising the possibility that reduction of the
amount of product from the mutant FBN1 allele might be a valid therapeutic
approach for MFS. A trans-acting hammerhead ribozyme (FBN1-RZ1) targeted to
the 5' end of the human FBN1 mRNA has been designed and synthesized, and
shown to cleave its target efficiently in vitro. FBN1-RZ1 cleavage is
magnesium dependent and efficient at both 37 and 50 degrees C. Delivery of
the FBN1-RZ1 ribozyme into cultured dermal fibroblasts, by receptor-
mediated endocytosis of a ribozyme-transferrin-polylysine complex,
specifically reduces both cellular FBN1 mRNA and the deposition of
fibrillin in the extracellular matrix. These results suggest that the use
of hammerhead ribozymes is a valid approach to the study of fibrillin gene
expression and possibly to the development of a therapeutic approach to
MFS.
相似文献
8.
Protective cytotoxic T lymphocyte responses against paramyxoviruses induced by epitope-based DNA vaccines: involvement of IFN-gamma 总被引:1,自引:0,他引:1
Hsu SC; Obeid OE; Collins M; Iqbal M; Chargelegue D; Steward MW 《International immunology》1998,10(10):1441-1447
Plasmid DNA vectors have been constructed with minigenes encoding a single
cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of
respiratory syncytial virus (RSV) or from the nucleoprotein of measles
virus (MV) with or without a signal sequence (also called secretory or
leader sequence). Following intradermal immunization, plasmids in which the
CTL epitopes were expressed in-frame with the signal sequence were more
effective at inducing peptide- and virus- specific CTL responses than
plasmids expressing CTL epitopes without the signal sequence. This
immunization resulted in protection against MV-induced encephalitis and a
significant reduction in viral load following RSV challenge. The reduction
of viral load following RSV challenge was abrogated by prior injection with
anti-IFN-gamma antibodies. These results highlight the ability of
epitope-based DNA immunization to induce protective immune responses to
well-defined epitopes and indicate the potential of this approach for the
development of vaccines against infectious diseases.
相似文献
9.
Ria R. Ghai Ann Carpenter Amanda Y. Liew Krystalyn B. Martin Meghan K. Herring Susan I. Gerber Aron J. Hall Jonathan M. Sleeman Sophie VonDobschuetz Casey Barton Behravesh 《Emerging infectious diseases》2021,27(4):1015
The ongoing global pandemic caused by coronavirus disease has once again demonstrated the role of the family Coronaviridae in causing human disease outbreaks. Because severe acute respiratory syndrome coronavirus 2 was first detected in December 2019, information on its tropism, host range, and clinical manifestations in animals is limited. Given the limited information, data from other coronaviruses might be useful for informing scientific inquiry, risk assessment, and decision-making. We reviewed endemic and emerging infections of alphacoronaviruses and betacoronaviruses in wildlife, livestock, and companion animals and provide information on the receptor use, known hosts, and clinical signs associated with each host for 15 coronaviruses detected in humans and animals. This information can be used to guide implementation of a One Health approach that involves human health, animal health, environmental, and other relevant partners in developing strategies for preparedness, response, and control to current and future coronavirus disease threats. 相似文献
10.
Frederick H Koh Jason MW Chua Joselyn LJ Tan Fung-Joon Foo Winson J Tan Sharmini S Sivarajah Leonard Ming Li Ho Bin-Tean Teh Min-Hoe Chew 《World journal of gastrointestinal surgery》2021,13(8):734-755
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献