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31.
Noninfectious Virus-Like Particle Antigen for Detection of Swine Vesicular Disease Virus Antibodies in Pigs by Enzyme-Linked Immunosorbent Assay 下载免费PDF全文
Young-Joon Ko Kang-Seuk Choi Jin-Ju Nah David J. Paton Jae-Ku Oem Ginette Wilsden Shien-Young Kang Nam-In Jo Joo-Ho Lee Jae-Hong Kim Hee-Woo Lee Jong-Myeong Park 《Clinical and Vaccine Immunology : CVI》2005,12(8):922-929
An inactivated SVDV antigen is used in current enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies to swine vesicular disease virus (SVDV). To develop a noninfectious recombinant alternative, we produced SVDV-like particles (VLPs) morphologically and antigenically resembling authentic SVDV particles by using a dual baculovirus recombinant, which expresses simultaneously the P1 and 3CD protein genes of SVDV under different promoters. Antigenic differences between recombinant VLPs and SVDV particles were not statistically significant in results obtained with a 5B7-ELISA kit, indicating that the VLPs could be used in the place of SVDV antigen in ELISA kits. We developed a blocking ELISA using the VLPs and SVDV-specific neutralizing monoclonal antibody 3H10 (VLP-ELISA) for detection of SVDV serum antibodies in pigs. The VLP-ELISA showed a high specificity of 99.9% when tested with pig sera that are negative for SVDV neutralization (n = 1,041). When tested using sera (n = 186) collected periodically from pigs (n = 19) with experimental infection with each of three different strains of SVDV, the VLP-ELISA detected SVDV serum antibodies as early as 3 days postinfection and continued to detect the antibodies from all infected pigs until termination of the experiments (up to 121 days postinfection). This test performance was similar to that of the gold standard virus neutralization test and indicates that the VLP-ELISA is a highly specific and sensitive method for the detection of SVDV serum antibodies in pigs. This is the first report of the production and diagnostic application of recombinant VLPs of SVDV. Further potential uses of the VLPs are discussed. 相似文献
32.
Yoshida A; Araki Y; Motoyama M; Kim SY; Sung H; Araki S; Miura K; Shirai M 《Human reproduction (Oxford, England)》1997,12(11):2499-2503
The objective of this study was to determine whether or not abnormalities
in the autosomal structure of the male partner have any influence on
fertilization and early embryo development after intracytoplasmic sperm
injection (ICSI). Thirty-seven couples in whom the male partners were
examined by the same andrologist were included in this study. Six couples
(group I) in whom the male partner possessed autosomal structural
abnormality underwent seven ICSI cycles. As a control group, 31 couples
(group II) in which the male partner was karyotypically normal underwent 41
ICSI cycles. Although the normal fertilization rates seen in group I were
significantly higher than those in group II (P < 0.05), there was no
significant difference in the cleavage rates between the two groups. We did
not perform the analysis of the female partner's chromosomes, but we
surmise that structural autosomal abnormalities in the male partner do not
adversely influence fertilization at ICSI and early development of embryos.
相似文献
33.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
34.
Characterization of immunodominant linear B-cell epitopes on the carboxy terminus of the rinderpest virus nucleocapsid protein 总被引:2,自引:0,他引:2
Choi KS Nah JJ Ko YJ Kang SY Yoon KJ Joo YS 《Clinical and diagnostic laboratory immunology》2004,11(4):658-664
The nucleocapsid (N) protein of rinderpest virus (RPV) is one of the most abundant and immunogenic viral proteins expressed during natural or experimental infection. To identify immunogenic epitopes on the N protein, different forms of RPV N protein, including the full-length protein (N(1-525)), an amino-terminal construct (N(1-179)), and a carboxy-terminal construct (N(414-496)), were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins. The antigenicity of each recombinant protein was evaluated by Western immunoblotting. All recombinants were recognized by hyperimmune RPV bovine antisera, indicating that immunoreactive epitopes may be present at both ends of the N protein. However, GST-N(414-496) was much more antigenic than GST-N(1-179) when tested with sera from vaccinated cattle, suggesting that an immunodominant or highly immunogenic epitope(s) may be located at the carboxy terminus of the N protein. Epitope mapping with overlapping peptides representing different regions of the carboxy terminus (amino acids 415 to 524) revealed three nonoverlapping antigenic sites in regions containing the residues (440)VPQVRKETRASSR(452) (site 1), (479)PEADTDPL(486) (site 2), and (520)DKDLL(524) (site 3). Among these, antigenic site 2 showed the strongest reactivity with hyperimmune anti-RPV bovine sera in a peptide enzyme-linked immunosorbent assay but did not react with hyperimmune caprine sera raised against peste-des-petits-ruminants virus, which is antigenically closely related to RPV. Identification of an immunodominant linear antigenic site at the carboxy terminus of the N protein may provide an antigen basis for designing diagnostics specific for RPV. 相似文献
35.
36.
Sam CK Cheng BScOptom Maurice KH Yap PhD MCOptom FAAO Ernest Goldschmidt MD DrSci Peter G Swann BSc MAppSc FCOptom FAAO honFIES Larry HY Ng PDOptom OD FAAO FBCLA Carly SY Lam PhD MSc MCOptom FAAO 《Clinical & experimental optometry》2008,91(4):373-378
Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography. 相似文献
37.
Ginseng and ginsenoside Rg3, a newly identified active ingredient of ginseng, modulate Ca2+ channel currents in rat sensory neurons 总被引:4,自引:0,他引:4
There is increasing evidence that ginseng influences pain modulation. In spite of extensive behavior studies, the detailed mechanism of ginseng actions at the cellular level and the identity of the active substance have not been elucidated yet. Whole-cell patch-clamp recordings were used to examine the modulation of high-voltage-activated Ca2+ channel currents by ginseng total saponins and its various individual ginsenosides in rat dorsal root ganglion neurons. Application of ginseng total saponins suppressed Ca2+ channel currents in a dose-dependent manner. Occlusion experiments using selective blockers revealed that ginseng total saponins could modulate L-, N-, and P-type currents. The co-application of ginseng total saponins and the gamma-opioid receptor agonist, D-Ala(2), N-MePhe(4), Gly(5)-ol-enkephalin (DAMGO), produced non-additive effects in most cells tested and each effect was significantly relieved by a depolarizing prepulse. Overnight treatment of cells with pertussis toxin profoundly reduced the inhibition. Furthermore, we now report that ginsenoside Rg3, among the major fractions of ginseng saponins, is a newly identified active component for the inhibition. These results suggest that the modulation of Ca2+ channels by ginseng total saponins, in particular by ginsenoside Rg3, could be part of the pharmacological basis of ginseng-mediated antinociception. 相似文献
38.
Functional expression of a novel ginsenoside Rf binding protein from rat brain mRNA in Xenopus laevis oocytes 总被引:2,自引:0,他引:2
We have shown that ginsenoside Rf (Rf) regulates voltage-dependent Ca(2+) channels through pertussis toxin (PTX)-sensitive G proteins in rat sensory neurons. These results suggest that Rf can act through a novel G protein-linked receptor in the nervous system. In the present study, we further examined the effect of Rf on G protein-coupled inwardly rectifying K(+) (GIRK) channels after coexpression with size-fractionated rat brain mRNA and GIRK1 and GIRK4 (GIRK1/4) channel cRNAs in Xenopus laevis oocytes using two-electrode voltage-clamp techniques. We found that Rf activated GIRK channel in a dose-dependent and reversible manner after coexpression with subfractions of rat brain mRNA and GIRK1/4 channel cRNAs. This Rf-evoked current was blocked by Ba(2+), a potassium channel blocker. The size of rat brain mRNA responding to Rf was about 6 to 7 kilobases. However, Rf did not evoke GIRK current after injection with this subfraction of rat brain mRNA or GIRK1/4 channel cRNAs alone. Other ginsenosides, such as Rb(1) and Rg(1), evoked only slight induction of GIRK currents after coexpression with the subfraction of rat brain mRNA and GIRK1/4 channel cRNAs. Acetylcholine and serotonin almost did not induce GIRK currents after coexpression with the subfraction of rat brain mRNA and GIRK1/4 channel cRNAs. Rf-evoked GIRK currents were not altered by PTX pretreatment but were suppressed by intracellularly injected guanosine-5'-(2-O-thio) diphosphate, a nonhydrolyzable GDP analog. These results indicate that Rf activates GIRK channel through an unidentified G protein-coupled receptor in rat brain and that this receptor can be cloned by the expression method demonstrated here. 相似文献
39.
Stress, coping, and depression in non-ulcer dyspepsia patients 总被引:7,自引:0,他引:7
Thirty adults with upper gastrointestinal symptoms in the absence of structural organic disease diagnosed with non-ulcer dyspepsia (NUD) were compared to 30 healthy adults who had visited the hepatobiliary clinic for medical evaluation of non-organic complaints without NUD. Medical investigation in both groups were negative. Before independent gastrointestinal physicians conducted diagnostic evaluations, all subjects were evaluated for anxiety and depressive symptoms, stressful life events, coping style, and social support. The measures included Symptom Checklist 90-Revised (SCL-90-R), Beck Depression Inventory (BDI), Spielberger State-Trait Anxiety Inventory (STAI), Ways of Coping Checklist, and Interpersonal Support Evaluation List, and a self-report questionnaire, which measured the quantity of perceived stressful life events. The NUD patients reported significantly more symptoms of depression, more perceived stressful life events, less problem-focused coping, and less social support than the control subjects. Depressive symptoms were negatively correlated with interpersonal support, whereas, problem-focused coping was positively correlated with interpersonal support in the NUD patients. The two groups did not differ significantly in terms of anxiety and emotion-focused coping. The implications of these findings for the diagnosis and treatment of NUD are discussed. 相似文献