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71.
A small quantity of extracellular calcium is required for the stimulation of lymphocytes by mitogens such as plant lectins. Lectin binding to the lymphocyte surface and early postbinding events that eventually lead to DNA synthesis are calcium dependent. Mitogenic lectins such as PHA and Con-A rapidly increase the size of an exchangeable pool of cell calcium and cause a smaller rise in intracellular ionized calcium. The increase in ionized calcium is so small (100-200 nM), however, that no increase in total cell calcium is measurable. When lymphocytes are stimulated by a lectin, the rate of calcium entry into the cell increases, but the plasma membrane calcium extrusion pump can prevent the total cell calcium from increasing measurably. The calcium ionophore A23187 is a lymphocyte mitogen and causes an increase in the exchangeable, ionized, and total cell calcium. The former two effects may be causal in mitogenesis; the latter effect is cytotoxic. With A23187 treatment, the rate of calcium influx exceeds the maximum rate of the plasma membrane extrusion pump and cell calcium increases in proportion to the concentration of A23187. The mitochondria, by virtue of their high membrane potential, provide a sink for the buffering of cytoplasmic calcium after A23187 treatment. Thus, the plasma membrane or mitochondria regulate the distribution of lymphocyte calcium when the cell is stimulated by mitogenic lectins or ionophores. The evidence strongly suggests that an alteration in calcium pools or an increase in cytoplasmic ionized calcium plays a role in the initiation of the biochemical reactions that lead to mitogen-induced lymphocyte proliferation in vitro and, perhaps, to the immune response. 相似文献
72.
M Silengo E Belligni C Molinatto G Baldassare E Biamino N Chiesa O Zuffardi S Girirajan EE Eichler GB Ferrero 《Clinical genetics》2010,77(1):28-31
Silengo M, Belligni E, Molinatto C, Baldassare G, Biamino E, Chiesa N, Zuffardi O, Girirajan S, Eichler EE, Ferrero GB. Eyebrow anomalies as a diagnostic sign of genomic disorders. Microdeletions and microduplications in the human genome, termed genomic disorders, contribute to a high proportion of human multisystemic neurodevelopmental diseases and are detected by array‐based comparative genomic hybridization (aCGH). In general, most genomic disorders are associated with craniofacial and skeletal features and behavioural abnormalities, in addition to learning disability and developmental delay (LD/DD). Specifically, recognition of a characteristic ‘acial gestalt’ has been the key to distinguish one genomic disorder from the other. Here, we report our experience concerning the relevance of abnormal eyebrow pattern as a diagnostic indicator of specific genomic disorders. 相似文献
73.
Tjitske Hielkema Elisa G Hamer Heleen A Reinders-Messelink Carel GB Maathuis Arend F Bos Tineke Dirks Lily van Doormaal Johannes Verheijden Carla Vlaskamp Eline Lindeman Mijna Hadders-Algra 《BMC pediatrics》2010,10(1):1-8
Background
Bronchiolitis is the most common reason for admission of infants to hospital in developed countries. Fluid replacement therapy is required in about 30% of children admitted with bronchiolitis. There are currently two techniques of fluid replacement therapy that are used with the same frequency-intravenous (IV) or nasogastric (NG). The evidence to determine the optimum route of hydration therapy for infants with bronchiolitis is inadequate. This randomised trial will be the first to provide good quality evidence of whether nasogastric rehydration (NGR) offers benefits over intravenous rehydration (IVR) using the clinically relevant continuous outcome measure of duration of hospital admission.Methods/Design
A prospective randomised multi-centre trial in Australia and New Zealand where children between 2 and 12 months of age with bronchiolitis, needing non oral fluid replacement, are randomised to receive either intravenous (IV) or nasogastric (NG) rehydration. 750 patients admitted to participating hospitals will be recruited, and will be followed daily during the admission and by telephone 1 week after discharge. Patients with chronic respiratory, cardiac, or neurological disease; choanal atresia; needing IV fluid resuscitation; needing an IV for other reasons, and those requiring CPAP or ventilation are excluded. The primary endpoint is duration of hospital admission. Secondary outcomes are complications, need for ICU admission, parental satisfaction, and an economic evaluation. Results will be analysed using t-test for continuous data, and chi squared for categorical data. Non parametric data will be log transformed.Discussion
This trial will define the role of NGR and IVR in bronchiolitisTrail registration
The trial is registered with the Australian and New Zealand Clinical Trials Registry - ACTRN12605000033640 相似文献74.
75.
76.
Twillman RK 《Journal of pain & palliative care pharmacotherapy》2003,17(2):83-88
The 10th World Congress on Pain, the triennial meeting of the International Association for the Study of Pain, continued the series' tradition as one of the premier international meetings for pain clinicians and scientists. At this meeting, held in August 2002 in San Diego, California, a broad spectrum of topics was presented, with substantial representation in both the clinical and basic science realms. Increased understanding of basic pain mechanisms, potential new targets for drug treatment of pain, ethical issues, and psychological interventions for pain were all areas of considerable interest. 相似文献
77.
78.
Akanchha?Kesari Hanna?Rennert Debra?GB?Leonard Balraj?MittalEmail author 《BMC medical genetics》2005,6(1):22
Background
Spinal muscular atrophy (SMA) represents the second most common fatal autosomal recessive disorder after cystic fibrosis. Due to the high carrier frequency, the burden of this genetic disorder is very heavy in developing countries like India. As there is no cure or effective treatment, genetic counseling becomes very important in disease management. SMN1 dosage analysis results can be utilized for identifying carriers before offering prenatal diagnosis in the context of genetic counseling. 相似文献79.
Progesterone stimulates p42 extracellular signal-regulated kinase (p42erk) in human spermatozoa 总被引:1,自引:3,他引:1
Luconi M; Krausz C; Barni T; Vannelli GB; Forti G; Baldi E 《Molecular human reproduction》1998,4(3):251-258
Mitogen-activated protein kinases (MAPK), also known as extracellular
signal-regulated kinases (ERKs) are cytoplasmic and nuclear
serine/threonine kinases involved in signal transduction of several
extracellular effectors. Recently, we have demonstrated that ERKs are
present in spermatozoa and are involved in the regulation of the process of
capacitation. We report here the effect of progesterone, a well-known
inducer of the acrosome reaction in mammalian spermatozoa, on the
immunolocalization, phosphorylation and activity of ERKs in capacitated
human spermatozoa. We demonstrated that short-term incubation of
spermatozoa with progesterone induces phosphorylation and activation of
ERKs, resulting in redistribution of the proteins from the post-acrosomal
region to the equatorial segment within the sperm head. To investigate the
role of ERKs on the biological effects of progesterone, we used the MAPK
cascade inhibitor PD098059, which strongly inhibited progesterone-induced
activation of ERK-2. This compound did not inhibit progesterone-induced
acrosome reaction, although it prevented redistribution of the enzyme to
the equatorial region of the sperm head. These results suggest that the two
processes, although temporally related, are independent. In conclusion, we
provide new insight into the signal transduction pathways involved in the
non- genomic action of progesterone in spermatozoa and suggest a possible
involvement of ERKs in the process of fertilization.
相似文献
80.
组织工程注射骨的体外实验研究 总被引:1,自引:0,他引:1
目的 :探索骨髓间充质细胞在纤维胶内体外成骨的可行性。方法 :5× 10 6~ 10× 10 6细胞 /毫升的骨髓间充质细胞植入前行细胞活力测定 ;植入纤维胶 ,体外培养 60 d后进行组织学、免疫组织化学分析。结果 :细胞在纤维胶内产生大量的特异性 型胶原 ,并有大量的钙质沉着。结论 :骨髓间充质细胞在纤维胶内可在体外培养的环境下生成大量的骨基质。 相似文献