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21.
Induction of IL-10+CD4+CD25+ T cells by grass pollen immunotherapy 总被引:24,自引:0,他引:24
BACKGROUND: Immunotherapy involves the modulation of allergen-specific T-cell responses, either T(H)2-to-T(H)1 immune deviation or, in bee venom-treated patients, induction of IL-10 production by CD4+CD25+ T cells. IL-10-producing CD4+CD25+ regulatory T cells have emerged as potential mediators of immune tolerance in numerous murine models of immunopathology. OBJECTIVE: The aim of this study was to evaluate the role of IL-10 production and CD4+CD25+ T cells in the response to grass pollen immunotherapy. METHODS: PBMCs were isolated from patients after 1 year of grass pollen immunotherapy and from matched untreated atopic and healthy control subjects. After 6 days of in vitro stimulation with Phleum pratense, production of IL-10, IL-5, IL-4, and IFN-gamma and proliferation and numbers of CD4+CD25+ T cells were measured. T cells were then stimulated for a further 5 hours with phorbol 12-myristate 13-acetate and ionomycin and assessed for intracellular IL-10 by means of flow cytometry. RESULTS: Patients undergoing immunotherapy produced significantly more IL-10 than atopic control subjects (patients undergoing immunotherapy, 116 +/- 21 pg/mL [n = 11]; atopic patients, 30 +/- 5 pg/mL [n = 11]; P <.001), and the number of CD4+CD25+ cells identified after allergen stimulation was also greater in the immunotherapy group. The numbers of CD4+CD25+ T cells correlated positively with activation as measured by proliferation in both of the control groups but not in the immunotherapy group. Moreover, only T cells from patients undergoing immunotherapy were positive for intracellular IL-10, and these were almost exclusively CD4+CD25+ cells. CONCLUSION: Grass pollen immunotherapy results in a population of circulating T cells that express the IL-10(+) CD4+CD25+ phenotype in response to allergen restimulation. 相似文献
22.
Consensus statement on the treatment of allergic rhinitis. European Academy of Allergology and Clinical Immunology 总被引:14,自引:0,他引:14
23.
Bilateral simultaneous tubal sextuplets: pregnancy after in-vitro fertilization--embryo transfer following salpingectomy 总被引:2,自引:1,他引:2
The presence of a damaged tube has been suggested in recent studies to have
a negative effect on in-vitro fertilization (IVF) outcome. Performing
bilateral salpingectomy prior to IVF to maximize pregnancy rates may also
result in unnecessary surgery. This case is also an example of the
occurrence of interstitial pregnancy after salpingectomy. This unusual type
of ectopic pregnancy must be kept in mind when evaluating a patient
suspected of a possible early abnormal gestation after assisted
reproductive technolologies.
相似文献
24.
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
25.
Nouri-Aria KT Irani AM Jacobson MR O'brien F Varga EM Till SJ Durham SR Schwartz LB 《The Journal of allergy and clinical immunology》2001,108(2):205-211
BACKGROUND: Basophils represent an important source of inflammatory mediators and cytokines after IgE-dependent activation in human beings. OBJECTIVE: To assess the role of basophils in allergic asthma, we measured the number of basophils in the bronchial mucosa and their capacity to express IL-4 mRNA and protein during allergen-induced late asthmatic responses. METHODS: Fiberoptic bronchoscopic bronchial biopsies were obtained at 24 hours from sites of segmental bronchial allergen challenge and control sites in 19 patients with atopic asthma and 6 nonatopic healthy volunteers. Basophil numbers were assessed by immunohistochemistry through use of mAb 2D7. IL-4 mRNA--positive cells were detected through use of in situ hybridization and colocalized to basophils through use of sequential immunohistochemistry/in situ hybridization. IL-4 protein was detected and colocalized to basophils through use of dual immunohistochemistry. RESULTS: After allergen challenge, there was an increase in the median number of 2D7-positive basophils per square millimeter in the bronchial mucosa in patients with asthma (0.9 cells/mm(2) at baseline to 8.8 cells/mm(2) after challenge; P =.002), which also was significantly higher than what was seen in nonasthmatic controls (P =.01). Similarly, IL-4 mRNA--positive cells were increased at 24 hours in patients with asthma (1.4 to 14) in comparison with controls (0 to 0; P =.02). Colocalization studies revealed that 15% and 41% of the basophil population in patients with asthma after allergen-challenge expressed, respectively, IL-4 mRNA and protein. Conversely, 19% of IL-4 mRNA-positive cells and 72% of IL-4 protein--positive cells were accounted for by basophils. CONCLUSION: After allergen provocation in sensitive patients with atopic asthma, basophils are recruited to the bronchial mucosa and express IL-4 mRNA and protein, which might contribute to local IgE synthesis and/or tissue eosinophilia or other aspects of allergic inflammation during late responses and ongoing asthma. 相似文献
26.
The impact of hydrosalpinx (HSPX) on in-vitro fertilization (IVF) outcome
has recently been the subject of intense debate. Most, but not all, studies
have reported decreased implantation and pregnancy rates and increased
early pregnancy loss in HSPX patients. This has led to prophylactic
salpingectomies prior to IVF in HSPX patients despite the lack of any
prospective studies to suggest that any improvement will occur. Women with
HSPX constitute a heterogeneous population because some conceive easily
with IVF while others do not until after surgical correction. HSPX also
increases in size with ovarian stimulation, and can cause implantation
failure by fluid reflux into the uterine cavity. Careful assessment of the
endometrial lining is mandatory in HSPX to rule out fluid reflux from the
HSPX. We present two case reports of patients whose HSPX enlarged with
ovarian stimulation, causing fluid reflux into the uterine cavity which was
only noted after human chorionic gonadotrophin (HCG) administration.
相似文献
27.
Wilson DR Nouri-Aria KT Walker SM Pajno GB O'Brien F Jacobson MR Mackay IS Durham SR 《The Journal of allergy and clinical immunology》2001,107(6):971-976
BACKGROUND: Tissue eosinophilia and infiltration by T(H)2-type T cells are characteristic features of allergic rhinitis both after allergen challenge and during natural allergen exposure. Specific immunotherapy inhibits allergen-induced nasal eosinophilia. OBJECTIVES: We sought to assess, in the context of a randomized trial, the relationships between symptomatic improvement after immunotherapy and eosinophil numbers and IL-5 expression in the nasal mucosa during the pollen season. METHODS: Nasal biopsy specimens were taken from 37 adults with severe summer hay fever at baseline (out of season) and at peak season after 2 years of treatment with a depot grass pollen extract or placebo. Biopsy specimens were processed for immunohistochemistry by using mAbs against eosinophils (EG2), T cells (CD3), and IL-2 receptor-positive cells (CD25), as well as for in situ hybridization by using a sulfur 35-labeled antisense riboprobe directed against IL-5. RESULTS: Immunotherapy significantly reduced symptoms (49%, P =.01) and medication requirements (80%, P =.007) compared with placebo. There was a 400% increase (P =.004) in eosinophils during the pollen season in placebo-treated patients, which was inhibited in the immunotherapy group (20% increase, P =.04 between groups). Seasonal increases were also observed for CD25(+) cells (P =.002), CD3(+) cells (P =.02), and IL-5 mRNA-expressing cells (P =.03) in the placebo group but not in the immunotherapy group. A significant correlation was observed between eosinophils and IL-5 expression (r = 0.5, P <.05). Both eosinophils (r = 0.6, P <.02) and IL-5 (r = 0.6, P <.02) correlated with symptoms after immunotherapy. CONCLUSION: Improvement in symptoms after grass pollen immunotherapy may result, at least in part, from inhibition of IL-5-dependent tissue eosinophilia during the pollen season. 相似文献
28.
A Crocker C Lee G Aboko-Cole C Durham 《Journal of the National Medical Association》1992,84(8):697-706
The copper-deficient rat-trypanosome system was used to study copper deficiency in Sprague Dawley rats infected with Trypanosoma lewisi. Throughout the observational period, animals on the deficient diet had lower plasma and liver copper concentrations compared with complete and pair-fed animals. In all dietary groups, the food intake and body weight changes of rats inoculated with T lewisi showed significant increases over the noninoculated controls. The rate of these indices were significantly less in the copper-deficient animals compared with the animals fed complete diets. Copper-deficient and pair-fed control rats showed greater numbers of parasites than controls throughout the infection. The duration of the trypanosomal infection was longer in copper-deficient rats compared with other groups. In all of the dietary groups, severe depression in the primary and secondary antibody responses (IgM and IgG) to in vivo immunization with sheep erythrocytes was observed in infected animals over noninfected controls. The results of the present study indicate that during copper deficiency, there are significant changes in food consumption and body weight and enhanced susceptibility to infection as measured by an increased parasitemia and depression in the antibody responses. 相似文献
29.
Frawley KA Durham K Stafford M Booth P 《Journal of AHIMA / American Health Information Management Association》1993,64(10):suppl 4 p. following p. 16
30.
The specific binding of [3H]estradiol-17 beta-(beta-D-glucuronide) ([3H]E217G) was examined in isolated basolateral (bLPM) and canalicular (cLPM) liver plasma membranes. Two distinct binding sites were identified in each membrane fraction by competition and saturation experiments. Binding parameters obtained from competition studies were: Kd1 = 26 nM, Bmax1 = 0.26 pmol/mg protein; Kd2 = 2.6 microM, Bmax2 = 27 pmol/mg protein for bLPM; and Kd1 = 81 nM, Bmax1 = 0.61 pmol/mg protein; Kd2 = 6.7 microM, Bmax2 = 79 pmol/mg protein for cLPM. Binding parameters obtained from saturation experiments were not significantly different. There was no Na+ requirement for binding. Kinetic dissociation experiments showed that binding was reversible and revealed two components. The dissociation rate constants did not vary with the method of dilution of radioligand, i.e. by "infinite" volume, or excess unlabeled ligand, thus ruling out the possibility of cooperativity. The ability of a series of compounds to inhibit the binding of [3H]E217G was also examined. In bLPM, taurocholate (TC), estrone sulfate (E1SO4) and bromosulfophthalein (BSP) were able to compete with both binding sites, whereas estriol-17 beta-(beta-D-glucuronide) (E317G), estriol-16 alpha-(beta-D-glucuronide) (E316G), testosterone glucuronide (TG), estradiol-3-(beta-D-glucuronide) (E23G), estriol-3-(beta-D-glucuronide) (E(3)3G), cholate and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) were able to inhibit binding to only the low-affinity site. In cLPM, only the cholestatic steroid D-ring glucuronides (E(3)17G, E(3)16G and TG) and TC were able to compete with both sites, whereas the non-cholestatic steroid A-ring glucuronides (E(2)3G and E(3)3G), BSP and DIDS competed for only the low-affinity site. Based on the observed substrate specificities, the low-affinity sites in bLPM and cLPM are postulated to represent multispecific organic anion carriers. The high-affinity site in cLPM may play a role in mediating steroid D-ring glucuronide-induced cholestasis. 相似文献