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91.
AIMS: To define epidemiology, clinical disease, and outcome of gemella bacteraemia by 16S rRNA gene sequencing. To examine the usefulness of the Vitek, API, and ATB systems in identifying two gemella species. METHODS: All alpha haemolytic streptococci other than Streptococcus pneumoniae isolated from blood cultures during a six year period were identified by conventional biochemical methods, the Vitek system, and the API system. 16S rRNA gene sequencing was performed on all isolates identified by both kits as gemella with >or= 95% confidence or by either kit as any bacterial species with < 95% confidence. The ATB expression system was used to identify the two isolates that were defined as gemella species by 16S rRNA gene sequencing. RESULTS: Of the 302 alpha haemolytic streptococci other than S pneumoniae isolated, one was identified as Gemella morbillorum, and another as Gemella haemolysans by 16S rRNA gene sequencing. The patient with monomicrobial G morbillorum bacteraemia was a 66 year old man with community acquired infective endocarditis with septic thromboemboli. The patient with G haemolysans bacteraemia was a 41 year old woman with hospital acquired polymicrobial bacteraemia during the neutropenic period of an autologous bone marrow transplant for non-Hodgkin's lymphoma, the first case of its kind in the English literature. The API and ATB expression systems only identified the second strain as G haemolysans at 94% and 99% confidence, respectively, whereas the Vitek system identified none of the two strains correctly at > 70% confidence. CONCLUSIONS: Gemella bacteraemia is uncommon. 16S rRNA gene sequencing is the method of choice for identification of gemella and gemella-like isolates. 相似文献
92.
HLA and Thyrotoxicosis (Graves' Disease) in Chinese 总被引:1,自引:0,他引:1
S. H. Chan P. P. B. Yeo K. F. Lui G. B. Wee K. T. Woo P. Lim J. S. Cheah 《Tissue antigens》1978,12(2):109-114
HLA locus A and B typing was performed on 86 Chinese thyrotoxicosis (Graves' Disease) patients and 238 normal Chinese subjects. The frequency of HLA-Bw46 (Sin 2) was found to be significantly higher among the patients than controls (X2 = 26.15, corrected P <.003, relative risk = 3.74). The risk associated with Bw46 was reflected in the Bw46 heterozygotes. The relative risks of the joint occurrence of Bw46/B40 and Bw46/B13 were 8.74 and 5.88 respectively. 相似文献
93.
C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro 总被引:1,自引:0,他引:1
We have previously shown that activated C1s complement and activated T
cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation
of desLys58 beta2m. This process can specifically be inhibited by
C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously
added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed
lymphocyte culture (MLC) increased the endogenous production of IL-2 and
the generation of allo-specific cytotoxic T lymphocytes. C1-inh was
purified from fresh human plasma and added to human or murine MLC and
mitogen-stimulated lymphocyte cultures grown in the presence of
complement-inactivated serum. Read-outs were cell proliferation, lymphokine
production and development of T cell-mediated cytotoxicity. We found that
addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte
cultures inhibited proliferation, the development of allospecific cytotoxic
activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12
and IFN-gamma. These data clearly demonstrate a regulatory function of
C1-inh on T cell- mediated immune functions.
相似文献
94.
Esophageal ulceration triggers expression of hypoxia-inducible factor-1 alpha and activates vascular endothelial growth factor gene: implications for angiogenesis and ulcer healing 下载免费PDF全文
Baatar D Jones MK Tsugawa K Pai R Moon WS Koh GY Kim I Kitano S Tarnawski AS 《The American journal of pathology》2002,161(4):1449-1457
95.
Amy H. Kim Paul M. Macev Ph.D. Mary A. Woo Pearl L. Yu Thomas G. Keens David Gozal Ronald M. Harper 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(3):109-115
Summary Question of the Study Congenital central hypoventilation syndrome (CCHS) subjects exhibit diminished respiratory-related heart rate variation in addition to defining characteristics of CO2 insensitivity and reduced ventilatory drive during sleep. Loss of cardiovascular and breathing coupling may diminish blood pressure influences on breathing; such influences may be determined by evaluating cardiorespiratory responses to different pressor challenges.
Patients and Methods Ten children with CCHS and 10 age- and gender-matched controls were subjected to a forehead cold pressor challenge and to Valsalva maneuvers. Heart and respiratory rates and variability during 30-s baseline and 120-s challenge periods were assessed with scatterplot displays and by analysis of variance procedures.
Results Cold pressor challenges enhanced breathing efforts and increased respiratory-related heart rate variation in controls but not in CCHS patients, while lower frequency heart rate variability increased in both controls and CCHS subjects. Heart rate variation resulting from voluntary expiratory efforts was present but slightly reduced in CCHS. Respiratory and cardiac rate trends differed in control and CCHS cases.
Conclusions More-rapidly changing heart rate variation from spontaneous or reflexively-induced sources is diminished in CCHS but remains intact from voluntary expiratory efforts, as does slower variation. Loss of reflexive influences on breathing from blood pressure changes may attenuate a source of respiratory drive. 相似文献
Patients and Methods Ten children with CCHS and 10 age- and gender-matched controls were subjected to a forehead cold pressor challenge and to Valsalva maneuvers. Heart and respiratory rates and variability during 30-s baseline and 120-s challenge periods were assessed with scatterplot displays and by analysis of variance procedures.
Results Cold pressor challenges enhanced breathing efforts and increased respiratory-related heart rate variation in controls but not in CCHS patients, while lower frequency heart rate variability increased in both controls and CCHS subjects. Heart rate variation resulting from voluntary expiratory efforts was present but slightly reduced in CCHS. Respiratory and cardiac rate trends differed in control and CCHS cases.
Conclusions More-rapidly changing heart rate variation from spontaneous or reflexively-induced sources is diminished in CCHS but remains intact from voluntary expiratory efforts, as does slower variation. Loss of reflexive influences on breathing from blood pressure changes may attenuate a source of respiratory drive. 相似文献
96.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献
97.
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
98.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
99.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
100.
Kim NJ Park SJ Choi SH Lee MS Choo EJ Kwak YG Woo JH Ryu J Jeong JY Kim YS 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(3):260-265
To characterize the phenotypes and genotypes of erythromycin-resistant clinical isolates of Streptococcus pneumoniae in Korea and to evaluate the in vitro activity of telithromycin against these erythromycin-resistant isolates, we tested a total of 676 isolates of S. pneumoniae collected from 1997 to 2002 in a tertiary hospital in Seoul, Republic of Korea. MICs for erythromycin and telithromycin were determined by the agar dilution method. The macrolide resistance phenotypes of erythromycin-resistant isolates were determined by the erythromycin- clindamycin-rokitamycin triple disk (ECRTD) and MIC induction tests, whereas their macrolide resistance genotypes were determined by PCR for the erm(B), erm(A), subclass erm(TR), and mef genes. To discriminate between mef(A) and mef(E), PCR-restriction fragment length polymorphism (RFLP) analyses were performed. Of the 676 S. pneumoniae isolates, 459 (67.9%) were resistant to erythromycin. Of the 459 erythromycin-resistant isolates, 343 (74.7%) were assigned to the cMLS phenotype, 48 (10.4%) to the iMcLS phenotype, 4 (0.9%) to the iMLS phenotype, and 64 (14.0%) to the M phenotype. The erm(B) gene was detected in 251 (54.6%) isolates, the mef gene was detected in 64 (14.0%), and both the erm(B) and mef genes were detected in 144 (31.4%) isolates. All of the mef genes detected were identified as mef(E). Of the 459 erythromycin- resistant isolates, all but one were susceptible to telithromycin. The MIC(50)/MIC(90) to telithromycin of isolates carrying erm(B), mef(E), and both genes was 0.06/0.5 microg/ml, 0.03/0.125 microg/ml, and 0.5/1.0 microg/ml, respectively. Although the MICs of telithromycin for the erythromycin-resistant isolates varied according to genotype, telithromycin was very active against these erythromycin-resistant S. pneumoniae. 相似文献