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排序方式: 共有2195条查询结果,搜索用时 390 毫秒
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2.
Bošnjaković Petar Ivković Tomislav Ilić Miodrag Aracki Snežana 《Cardiovascular and interventional radiology》1992,15(4):217-220
Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment
of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using
retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual
stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning.
We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to
PTA. 相似文献
3.
4.
Marija Čarman-Kržan 《Inflammation research》1983,13(2-3):162-166
The antagonist-sensitive binding of [3H]mepyramine to beef aortic membranes was as expected for binding to histamine H1-receptors. [3H]mepyramine binds rapidly and in saturable fashion to the specific receptor sites, specific binding reaching equilibrium in 3 min at 37°CScatchard's analysis of the binding data gave a dissociation constant of 3.0 nM for the radioligand-receptor complex and maximal number of binding sites: 31 fmol/mg protein. In the competition studies histamine H1-antagonists are more potent inhibitors of radioligand binding than H2-antagonist. They inhibit [3H]mepyramine binding in the following order: mepyramine >triprolidine 相似文献
5.
Development of flow cytogenetics and physical genome mapping in chickpea (Cicer arietinum L.) 总被引:2,自引:0,他引:2
K. Vláčilová D. Ohri J. Vrána J. Číhalíková M. Kubaláková G. Kahl J. Doležel 《Chromosome research》2002,10(8):695-706
Procedures for flow cytometric analysis and sorting of mitotic chromosomes (flow cytogenetics) have been developed for chickpea (Cicer arietinum). Suspensions of intact chromosomes were prepared from root tips treated to achieve a high degree of metaphase synchrony. The optimal protocol consisted of a treatment of roots with 2mmol/L hydroxyurea for 18h, a 4.5-h recovery in hydroxyurea-free medium, 2h incubation with 10µmol/L oryzalin, and ice-water treatment overnight. This procedure resulted in an average metaphase index of 47%. Synchronized root tips were fixed in 2% formaldehyde for 20min, and chromosome suspensions prepared by mechanical homogenization of fixed root tips. More than 4×105 morphologically intact chromosomes could be isolated from 15 root tips. Flow cytometric analysis of DAPI-stained chromosomes resulted in histograms of relative fluorescence intensity (flow karyotypes) containing eight peaks, representing individual chromosomes and/or groups of chromosomes with a similar relative DNA content. Five peaks could be assigned to individual chromosomes (A, B, C, G, H). The purity of sorted chromosome fractions was high, and chromosomes B and H could be sorted with 100% purity. PCR on flow-sorted chromosome fractions with primers for sequence-tagged microsatellite site (STMS) markers permitted assignment of the genetic linkage group LG8 to the smallest chickpea chromosome H. This study extends the number of legume species for which flow cytogenetics is available, and demonstrates the potential of flow cytogenetics for genome mapping in chickpea. 相似文献
6.
Le Maréchal C Chen JM Le Gall C Plessis G Chipponi J Chuzhanova NA Raguénès O Férec C 《Human mutation》2004,23(2):205
Mutations in the serine protease inhibitor Kazal type 1 gene (SPINK1) encoding pancreatic secretory trypsin inhibitor (PSTI) have recently been found to be associated with chronic pancreatitis. Nevertheless, knowledge of severe mutations is particularly scarce, both in terms of number and in the extent of clinical information. The aim of this study was to expand the known spectrum of such mutations. 46 unrelated families, each including at least two pancreatitis patients and carrying neither cationic trypsinogen (PRSS1) mutations nor the frequent SPINK1 N34S mutation, participated in this study. The four exons and their flanking sequences of the SPINK1 gene were screened by denaturing high performance liquid chromatography analysis (DHPLC); and mutations were identified by direct sequencing. A heterozygous microdeletion mutation (c.27delC), which occurs within a symmetric element, was identified in two families. In one family, c.27delC showed segregation with the disease across two generations, with a penetrance of up to 75%. But in the other family, however, the same mutation manifested as a low-penetrance susceptibility factor. In addition, a novel heterozygous splicing mutation, c.87+1G>A (G>A substitution at nucleotide +1 of intron 2) was found in one family with familial pancreatitis. Our results also helped to resolve the sharply differing views about PSTI's role in pancreatitis. 相似文献
7.
Vladimíra Džugasová Margita Obernauerová Katarína Horváthová Mariana Vachová Martina Žáková Július Šubík 《Current genetics》1998,34(4):297-302
The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho
–/rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA,
is localized in the mitochondria and expressed in response to inositol and choline.
Received: 15 June / 15 July 1998 相似文献
8.
Marija Čarman-Kržan 《Inflammation research》1986,18(1-2):120-123
Agonist interaction with histamine H1-receptor in [3H] mepyramine bovine aortic membranes labeled with [3H] mepyramine is selectively regulated by cations and guanine nucleotides. GTP and his nonhydrolisable analog Gpp(NH)p' markedly decrease histamine affinity for [3H] mepyramine binding sites. The effect of GTP is reversed in the presence of divalent cation, magnesium. Calcium and sodium ions have little effect on histamine binding whereas magnesium ions decrease the affinity of histamine for the radioantagonist binding sites about tenfold.GTP has little effect on [3H] mepyramine binding and the interaction of H1-antagonist triprolidine with histamine H1-receptors. The above results indicate that the effect of guanine nucleotides, mono and divalent cations involves the effect on membrane signal transducing mechanism probably GTP-binding protein(s) cation regulatory site(s) rather than receptor binding site directly. 相似文献
9.
Mutations in the cationic trypsinogen gene and evidence for genetic heterogeneity in hereditary pancreatitis 总被引:9,自引:0,他引:9
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Férec C Raguénès O Salomon R Roche C Bernard JP Guillot M Quéré I Faure C Mercier B Audrézet MP Guillausseau PJ Dupont C Munnich A Bignon JD Le Bodic L 《Journal of medical genetics》1999,36(3):228-232
Hereditary pancreatitis (HP) is a rare inherited disorder, characterised by recurrent episodes of pancreatitis often beginning in early childhood. The mode of inheritance suggests an autosomal dominant trait with incomplete penetrance. The gene, or at least one of the genes, responsible for hereditary pancreatitis has been mapped to the long arm of chromosome 7 and a missense mutation, an arginine to histidine substitution at residue 117 in the trypsinogen cationic gene (try4) has been shown to segregate with the HP phenotype. The aim of this work was to investigate the molecular basis of hereditary pancreatitis. This study was performed on 14 HP families. The five exons of the trypsinogen cationic gene were studied using a specific gene amplification assay combined with denaturing gradient gel electrophoresis (DGGE). The present paper describes three novel mutations, namely K23R and N29I and a deletion -28delTCC in the promoter region. We also found a polymorphism in exon 4, D162D. In eight of these families we found a mutation which segregates with the disease. A segregation analysis using microsatellite markers carried out on the other families suggests genetic heterogeneity in at least one of them. Our findings confirm the implication of the cationic trypsinogen gene in HP and highlight allelic diversity associated with this phenotype. We also show that the pattern of inheritance of HP is probably complex and that other genes may be involved in this genetic disease. 相似文献
10.
Sexual dimorphism (SD) represents all the differences between males and females of the same species. SD of the murine lacrimal gland and the major effect of testosterone on its formation are well documented. Steroidogenic factor-1 (SF-1, NR5a1) is a nuclear receptor essential for the fetal development of steroid hormones producing organs and SF-1 knockout mice (Sf-1 KO) are therefore born without gonads and adrenal glands. The aim of this study was to investigate whether SD in lacrimal glands is present in the absence of exposure to sex hormones during development. Lacrimal glands from adult Sf-1 KO male and female mice without hormonal exposure, and from males that were treated with testosterone propionate (TP) prior to sacrifice, were examined. After sacrifice, glandular tissue was processed using standard histological procedures. Paraffin sections were analysed by stereology and immunostained against the androgen receptor (AR). Our results showed that there were no statistically significant differences in the mean volumes of acini, connective tissue or ductal system between males, females, and males on TP. The same pertains to the mean length of the ducts in all three groups. In the absence of sex hormones, sex chromosomes proved to be insufficient in inducing sexual dimorphism in LG. However, nuclei of the acinar cells in males on TP were positive for AR, whereas in males without TP no expression of AR was detected. Administration of TP induced the expression of AR in the nuclei of acinar cells of males but did not affect the morphology of LG. We conclude that SD in the lacrimal gland is not present in Sf-1 KO mice and this suggests that sex hormones have a major role in the development of SD in the lacrimal gland. 相似文献