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101.
102.
Seung Yong Park Hisashi Arase Keisuke Wakizaka Nakami Hirayama Shigehiro Masaki So-Ichiro Sato Jeffrey V. Ravetch Takashi Saito 《European journal of immunology》1995,25(7):2107-2110
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia. 相似文献
103.
We generated an antigen (streptococcal cell wall antigen)-specific T-cell line from peripheral blood mononuclear cells of a healthy donor with an intermediate response to streptococcal cell wall antigen. Proliferation of the T-cell line was completely blocked by a monoclonal antibody to HLA-DR. This line activated autologous CD8+ T cells in an antigen-specific manner in the presence of autologous monocytes. This activation was mediated by a factor derived from this line and was blocked by a monoclonal antibody against HLA class I molecules. The resultant CD8+ T blasts showed antigen-nonspecific suppression but no cytolytic activity. This antigen-specific generation of the CD8+ T-cell line in vitro by the antigen-specific CD4+ T-cell line is expected to contribute to analyses of functions of CD8+ T-cell subsets, particularly in the down-regulating system, at both cellular and molecular levels. 相似文献
104.
Satoshi Fujishita Noritoshi Shibuya Norio Niikawa Shigenobu Nagataki 《Journal of human genetics》1991,36(4):317-324
Polymerase chain reaction (PCR)-based diagnosis was carried out in 62 patients (57 probands) with Duchenne or Becker muscular dystrophy (DMD or BMD) and 226 members in 57 families. The PCR studies were also performed for carrier detection in 57 mothers and 58 sisters, and prenatal diagnosis of 4 fetuses at risk of DMD. The PCR with 7 sets of primers, which amplify 7 different exon-sequences of the dystrophin gene, detected gene deletion of at least one exon in 49% of the probands. The PCR with the other 4 primer sets, which amplify 3 intragenic loci, and subsequent endonuclease digestion detected in 84% of the mothers a heterozygous pattern in at least one such locus/segment. Using the same primer sets, carrier detection was successful in 5 sisters of familial DMD cases, while recombination between the ERT87 and the 3 end intragenic loci was observed in 11% of family members studied. Prenatal diagnosis was made in all the 4 fetuses; two males were affected, one male fetus non-affected, and the remaining one female fetus a carrier. Thus, the PCR study and the primers used in the present study are useful and convincing for rapid diagnosis of DMD and/or BMD. 相似文献
105.
Norio Fukuda Hideaki Fujita Takashi Fujita Shin’ichi Ishiwata 《Pflügers Archiv : European journal of physiology》1996,433(1-2):1-8
Skinned fibres from bovine ventricles exhibited spontaneous tension oscillations when MgADP and inorganic phosphate (Pi)
were added to the solution bathing fibres in the relaxed state (ADP-SPOC). A similar type of oscillation was observed at intermediate
concentrations of free Ca2+ in the absence of MgADP and Pi (Ca-SPOC). To investigate the correlation between ADP-SPOC and Ca-SPOC, we constructed two-dimensional
state diagrams of cardiac muscle using different concentrations of Pi (0–20 mM) and free Ca2+ [pCa=around 5 (+Ca2+), pCa=5.15–6.9 and +EGTA (–Ca2+)], with varying concentrations of MgADP (0–10 mM), with 2 mM MgATP and 2 mM free Mg2+ maintaining ionic strength at 0.15±0.01 M, pH 7.0, 25 °C. The three-dimensional (pCa-Pi-MgADP) state diagram thus obtained
was divided into three regions, i.e. the contraction region in which tension oscillation was undetectable, the spontaneous
tension oscillation (SPOC) region and the relaxation region. We found that the regions of ADP-SPOC and Ca-SPOC were continuously
connected by a single oscillation region sandwiched between the contraction and relaxation regions. The state diagram, which
encompasses physiological conditions, shows that the probability of SPOC is higher in cardiac muscle than in skeletal muscle.
From these results, we suggest that, despite distinct ionic conditions, the molecular state of cross-bridges during SPOC is
common to both ADP-SPOC and Ca-SPOC.
Received 19 February 1996 / Received after revision: 16 July 1996 / Accepted: 14 August 1996 相似文献
106.
Han-Xiang Deng Jia-Hui Xia Mutsuo Ishikawa Norio Niikawa 《Journal of human genetics》1990,35(3):245-251
Parental origin and mechanism of formation of X chromosome structural anbormalities were studied in one each case of dup(X)(pter p11.4::p22.1qter), del(X)(qterp11:), i(X)(qtercenqter), and inv dup(X) (pterq22::q22pter) using various X-linked RFLPs as genetic markers. Segregation and densitometric analyses on polymorphic DNAs revealed that the dup(Xp) and the del(Xp) are both of paternal origin and the i(Xq) and i dic(X) are of maternal origin. The dup(Xp) had arisen by an unequal sister chromatid exchange and the del(Xp) had occurred through an intrachromosomal breakage-reunion mechanism, both in the paternal X chromosome. The i(Xq) had arisen either through centromere fission of a maternal X chromosome, followed by duplication, of its long-arm, or through a translocation between two maternal X chromosomes after meiotic crossing-over. The inv dup(X) arose through sister chromatid breakage and reunion in a maternal X chromosome. These results, together with those of previous studies, suggest that thede novo abnormalities due to events involving centromere disruption arise predominantly during oogenesis, while those due to simple breakage-reunion events occur preferentially during spermatogenesis. 相似文献
107.
Sasakawa T Higashi Y Sakuma S Hirayama Y Sasakawa Y Ohkubo Y Mutoh S 《International archives of allergy and immunology》2004,133(1):55-63
BACKGROUND: FK506 ointment (tacrolimus ointment, protopic) is a new drug therapeutically effective for patients with atopic dermatitis (AD). However, the mechanism of action of FK506 ointment on AD is not fully understood. METHODS: We examined the effect of FK506 ointment on mite antigen-induced dermatitis in NC/Nga mice. Clinical symptoms and ear thickness were recorded, and histopathological studies and in vitro analyses were performed. RESULTS: Topical application of FK506 ointment (0.03-0.3%) suppressed the development of dermatitis. In the lesional skin, both interleukin (IL)-4 and interferon (IFN)-gamma were detected, even though the IL-4+/IFN-gamma- T helper 2 (Th2) population was predominant in the regional lymph nodes (LNs). Topical application of FK506 treatment reduced the elevated level of both IL-4 and IFN-gamma in the skin, but did not decrease the expansion of the Th2 population in the LNs. CONCLUSIONS: Topical application of FK506 ointment suppresses dermatitis by inhibiting the activation of inflammatory cells locally, without systemic immune suppression, in this AD model. 相似文献
108.
K. Haukipuro N. Keränen E. Koivisto R. Lindholm R. Norio L. Punto 《Clinical genetics》1978,13(6):471-476
In a Finnish kindred consisting of 192 descendants from two marriages of a male ancestor born in 1868, the lumbar spines of 105 of the 170 living members were X-rayed. Spondylolysis was found in 22 individuals. In addition, six of them had spondylolisthesis, four had spina bifida occulta, and two had a transitional lumbar/sacral vertebra. Seven members of the kindred without spondylolysis had spina bifida occulta and 10 had transitional lumbar vertebrae.
The pedigree is consistent with autosomal dominant inheritance and incomplete (about 75 %) penetrance for spondylolysis. It raises the question of a common aetiology for several congenital disturbances in the formation of lumbar vertebrae and possibly supports the concept of a variable expressivity of a "spondylolysis gene". 相似文献
The pedigree is consistent with autosomal dominant inheritance and incomplete (about 75 %) penetrance for spondylolysis. It raises the question of a common aetiology for several congenital disturbances in the formation of lumbar vertebrae and possibly supports the concept of a variable expressivity of a "spondylolysis gene". 相似文献
109.
The hydrolethalus syndrome: delineation of a "new", lethal malformation syndrome based on 28 patients 总被引:7,自引:0,他引:7
We describe a lethal malformation syndrome in 28 newborn infants from 18 families. The main manifestations were hydrocephalus (often with an unusual structure of the brain and the occipital bone), very small mandible, Polydactyly, congenital heart defect, abnormalities of the respiratory organs, and (different from the Meckel syndrome) normal kidneys. Polyhydramnios and stillbirth or neonatal death were the rule. Autosomal recessive inheritance is evident. This syndrome is another in the group of rare recessive disorders which are found in Finland. Because of the 25 % recurrence risk and possibilities for prenatal diagnosis, this syndrome should be recognized by paediatricians and, because of the frequent stillbirths, also by obstetricians and pathologists. The name hydrolethalus syndrome (hydramnios, hydrocephalus, lethality) may be of help in this. 相似文献
110.