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排序方式: 共有624条查询结果,搜索用时 15 毫秒
1.
S Amoroso G F Di Renzo F Maurano P Maida M Taglialatela L Annunziato 《Experimental aging research》1987,13(1-2):85-87
Circulating prolactin (PRL) levels, dopamine (DA) content, in vitro basal and stimulus-evoked endogenous DA release from arcuate-periventricular nuclei median-eminence fragments were studied in young (4 months) and old (24-25 months) male rats of Sprague-Dawley strain. Serum PRL levels did not differ in young and aged animals. In addition DA tissue content, basal and K+- or d-amphetamine evoked endogenous DA release did not show age-related differences. These results suggest that in male rats of the Sprague-Dawley strain the activity of tuberoinfundibular dopaminergic (TIDA) neurons does not change during senescence, unlike what happens in other strains of rats. 相似文献
2.
3.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
4.
顾性初 《中国医药工业杂志》1995,(11)
抑制幽门螺杆菌产生的脲酶具有治疗胃炎和消化性溃疡的作用。用酚红指示剂和Berthelot试剂在96孔培养板上检测重组脲酶活性,其灵敏度指标酚红法每mg酶蛋白引起的每分钟吸光度变化。△A为6.9,而Berthelot法每mg酶蛋白引起的每分钟吸光度比值变化△A为313。结果表明用Berthelot试剂检测重组脲酶活性适宜在96孔培养板上大规模筛选天然产物中的脲酶抑制剂。 相似文献
5.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
6.
Day DJ; Speiser PW; Schulze E; Bettendorf M; Fitness J; Barany F; White PC 《Human molecular genetics》1996,5(12):2039-2048
Steroid 21-hydroxylase deficiency is among the most common inborn errors of
metabolism in man. Characterization of mutations in the 21- hydroxylase
gene (CYP21) has permitted genetic diagnosis, facilitated by the polymerase
chain reaction (PCR). The most common mutation is conversion of an A or C
at nt656 to a G in the second intron causing aberrant splicing of mRNA.
Homozygosity for nt656G is associated with profoundly deficient adrenal
cortisol and aldosterone synthesis, secondary hypersecretion of adrenal
androgens, and a severe form of congenital adrenal hyperplasia (CAH)
characterized by ambiguous genitalia and/or sodium wasting in newborns.
During the course of genetic analysis of CYP21 mutations in CAH families,
we and others have noticed a number of relatives genotyped as nt656G
homozygotes, yet showing no clinical signs of disease. A number of lines of
evidence have led us to propose that the putative asymptomatic nt656G/G
individuals are incorrectly typed due to dropout of one haplotype during
PCR amplification of CYP21. For prenatal diagnosis, we recommend that
microsatellite typing be used as a supplement to CYP21 genotyping in order
to resolve ambiguities at nt656.
相似文献
7.
Macrophage-derived chemokine production by activated human T cells in vitro and in vivo: preferential association with the production of type 2 cytokines 总被引:12,自引:0,他引:12
Galli G Chantry D Annunziato F Romagnani P Cosmi L Lazzeri E Manetti R Maggi E Gray PW Romagnani S 《European journal of immunology》2000,30(1):204-210
Macrophage-derived chemokine (MDC), a potent chemoattractant for chronically activated Th2 lymphocytes, is constitutively expressed by dendritic cells, B cells, macrophages, and thymic medullary epithelial cells, whereas monocytes, NK cells, and T lymphocytes produce MDC only upon appropriate stimulation. In this study, we show in vitro MDC production also by activated T cells, which preferentially associate with the production of Th2 cytokines, IL-4, IL-5, and IL-6, and inversely correlate with the production of the Th1 cytokine, IFN-gamma. Moreover, high levels of MDC were detected in the sera of the great majority of subjects suffering from mycosis fungoides/Sézary syndrome or atopic dermatitis, which are considered as disorders characterized by the predominant expansion and activation of Th2 cells, respectively. By contrast, serum MDC levels in subjects with multiple sclerosis or Crohn's disease, which are characterized by a Th1 predominance, did not differ significantly from those of healthy controls. Finally, MDC expression was detected in the skin biopsy specimens of subjects with atopic dermatitis, where it was expressed by both dendritic cells and T lymphocytes. Taken together, these findings suggest that MDC production by activated T cells may occur both in vitro and in vivo, particularly in association with Th2 cytokines, thus providing an important amplification circuit for Th2-mediated responses. 相似文献
8.
G. F. Di Renzo S. Amoroso M. Taglialatela L. Annunziato 《Naunyn-Schmiedeberg's archives of pharmacology》1986,333(3):224-228
Summary The possible involvement of calmodulin in the process of endogenous dopamine (DA) release from arcuateperiventricular nuclei-median eminence fragments, containing tuberoinfundibular dopaminergic (TIDA) neurons, has been investigated in an in vitro incubation system. For this purpose the basal and K+-stimulated DA release was examined in the presence and in the absence of the different putative calmodulin antagonists, pimozide, trifluoperazine, penfluridol and N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide (W-7).Trifluoperazine and pimozide in concentrations up to 100 M were both uneffective in blocking K+-evoked DA release. Penfluridol in doses of 5 and 10 M, did not prevent 35 mM K+-induced endogenous DA release. It was able to reduce K+-stimulated DA release only at the very large concentration of 100 M.W-7 added in vitro to the hypothalamic fragments, prevented endogenous DA release evoked by 35 mM K+ in a dose-dependent manner. W-5, a chlorine deficient analogue of W-7, that interacts only weakly with calmodulin, failed to modify K+-stimulated endogenous DA release in doses up to 200 M.All the putative calmodulin antagonists used in the present study did not induce any change of basal DA release.IN conclusion the fact that most of the agents, except W-7, known to antagonize calmodulin-dependent processes in many biological systems failed to interfere with the release of endogenous DA from TIDA neurons seems to suggest that calmodulin does not play a crucial role in the process of DA release and that the inhibitory effect of W-7 on endogenous DA release may be better attributed to other mechanisms different from its anticalmodulin action. 相似文献
9.
Sarah Duncan-Park Claire Dunphy Jacqueline Becker Christine D’Urso Rachel Annunziato Joshua Blatter Carol Conrad Samuel B. Goldfarb Don Hayes Jr. Ernestina Melicoff Marc Schecter Gary Visner Brian Armstrong Hyunsook Chin Karen Kesler Nikki M. Williams Jonah N. Odim Stuart C. Sweet Lara Danziger-Isakov Eyal Shemesh 《American journal of transplantation》2021,21(9):3112-3122
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), p = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (p = .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888. 相似文献
10.
Taglialatela M Pannaccione A Iossa S Castaldo P Annunziato L 《Molecular pharmacology》1999,56(6):1298-1308
The inhibition of nitric oxide synthase by N-nitro-L-arginine methyl ester (0.03-3 mM) dose-dependently reduced nitric oxide (NO(*)) levels and enhanced the outward currents carried by human ether-a-gogo-related gene-1 (hERG1) K(+) channels expressed in Xenopus laevis oocytes, whereas the increase in NO(*) levels achieved by exposure to L-arginine (0.03-10 mM) inhibited these currents. Furthermore, four NO(*) donors belonging to such different chemical classes as sodium nitroprusside (1-1000 microM), 3-morpholino-sydnonimine (100-1000 microM), (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1, 2-diolate (NOC-18; 1-300 microM), and S-nitroso N-acetylpenicillamine (1-300 microM) dose-dependently inhibited hERG1 outward K(+) currents. By contrast, the NO(*) donor NOC-18 (0.3 mM) did not affect other cloned K(+) channels such as rat neuroblastoma-glioma K(+) channel 2, rat delayed rectifier K(+) channel 1, bovine ether-a-gogo gene, rat ether-a-gogo-related gene-2, and rat ether-a-gogo-related gene-3. The inhibitory effect of NO(*) donors on hERG1 K(+) channels was prevented by the NO(*) scavengers 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide and hemoglobin. The membrane permeable analog of cGMP, 8-bromo-cGMP (1 mM), failed to reproduce the inhibitory action of NO(*) donors on hERG1 outward currents; furthermore, the specific inhibitor of the NO(*)-dependent guanylyl cyclase, 1H-[1,2,4]oxadiazolo[4, 3-a]quinoxalin-1-one (50 microM), neither interfered with outward hERG1 K(+) currents nor prevented their inhibition by 0.3 mM NOC-18. Both L-arginine (10 mM) and NOC-18 (0.3 mM) counteracted the stimulatory effect on hERG1 outward currents induced by the radical oxygen species-generating system FeSO(4) (25 microM)/ascorbic acid (50 microM; Fe/Asc). Finally, L-arginine (10 mM) and NOC-18 (0.3 mM) inhibited both basal and Fe/Asc (0.1 mM/0.2 mM)-stimulated lipid peroxidation in X. laevis oocytes. Collectively, the present results suggest that NO(*), both endogenously produced and pharmacologically delivered, may exert in a cGMP-independent way an inhibitory effect on hERG1 outward K(+) currents via an interaction with radical oxygen species either generated under resting conditions or triggered by Fe/Asc. 相似文献