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81.
Specific [3H]dihydroalprenolol binding sites are enriched in the dorsal grey matter of rat spinal cord. Neonatal capsaicin treatment, known to cause a permanent loss of a population of primary afferent neurones, caused a significant loss of specific [3H]dihydroalprenolol binding sites from laminae of the dorsal horn. These results suggest that capsaicin-sensitive primary afferent terminals may bear presynaptic beta-adrenergic receptors. 相似文献
82.
Roy Patterson Irena M. Suszko Stephen G. Hendrix C.Raymond Zeiss 《The Journal of allergy and clinical immunology》1981,67(2):162-165
Aqueous extracts of tree pollen were partially purified and polymerized with methods previously established for preparation of ragweed and grass polymers. The polymerized tree preparations were antigenic as demonstrated by ability to elicit immediate-type skin reactivity in humans and to induce an immune response in rabbits. The polymerized tree antigen was 100- to 10,000-fold less skin reactive than monomer tree antigen in tree pollen-sensitive patients but both preparations had similar antigenicity in rabbits. These results demonstrate that polymerized tree antigens can be prepared and should have the therapeutic potential already demonstrated for polymerized ragweed preparations. 相似文献
83.
Frequency of cytokine polymorphisms in populations from western Europe,Africa, Asia,the Middle East and South America 总被引:15,自引:0,他引:15
Meenagh A Williams F Ross OA Patterson C Gorodezky C Hammond M Leheny WA Middleton D 《Human immunology》2002,63(11):1055-1061
PCR-SSOP identification procedures for IL-2, IL-6, IL-10, TNF-alpha and TNF-beta cytokine polymorphisms have been developed. Application of the procedures to a range of diverse geographically distributed populations has identified ethnic differences within the groups studied. Five populations were investigated, Northern Ireland, South African Zulu, Omani, Singapore Chinese and Mexican Mestizos. 相似文献
84.
Many gastrointestinal and pancreatic functions are under strong modulatory control by the brain via the vagus nerve. To start identifying location and neurochemical phenotype of the enteric neurons receiving functional vagal efferent input, we activated vagal preganglionic neurons either by electrical or chemical stimulation and examined the expression of phosphorylated CREB (c-AMP response element binding protein) and the immediate early gene c-Fos. There was no spontaneous expression of both markers in the pancreas and considerable spontaneous expression of p-CREB but not Fos in the upper GI-tract. Unilateral electrical vagal stimulation-induced p-CREB was found in 40% of neurons in the head of the pancreas. Fos expression was found in 70-90% of neurons in the esophagus and stomach, in 20-30% of myenteric plexus neurons and 5-15% in submucosal neurons of the proximal duodenum. Double-labeling experiments showed that a majority of pancreatic neurons and about 25-35% of neurons in the stomach and duodenum contain NADPH-diaphorase and that many of these receive functional vagal input. Other neurons that can be vagally activated contain gastrin-releasing peptide or calretinin. Chemical stimulation of the dorsal surface of the caudal brainstem with the stable TRH analog RX77368 resulted in selective activation of vagal efferents with expression of Fos in a small number of gastric myenteric plexus neurons. The results demonstrate the suitability of this method to investigate magnitude and local distribution of vagal input to the enteric nervous system as well as specificity of its neurochemically coded pathways. They represent the first step in the identification of function-specific units of parasympathetic vagal outflow. 相似文献
85.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
86.
87.
Watanabe Y Hashimoto S Kakita A Takahashi H Ko J Mizuno M Someya T Patterson PH Nawa H 《Neuroscience research》2004,48(3):345-353
Cytokines have been implicated in the etiology or pathology of various psychiatric diseases of developmental origin such as autism and schizophrenia. Leukemia inhibitory factor (LIF) is induced by a variety of brain insults and known to have many influences on mature and immature nervous system. Here, we assessed the neurobehavioral and pathological consequences of peripheral administration of LIF in newborn rats. Subcutaneous LIF injection induced STAT3 phosphorylation in many brain regions and increased glial fibrillary acidic protein (GFAP) immunoreactivity in the neocortex, suggesting that LIF had direct effects in the central nervous system. The LIF-treated rats displayed decreased motor activity during juvenile stages, and developed abnormal prepulse inhibition in the acoustic startle test during and after adolescence. They displayed normal learning ability in active avoidance test, however. Brain neuronal structures and startle responses were grossly normal, except for the cortical astrogliosis during neonatal LIF administration. These results indicate that LIF induction in the periphery of the infant has a significant, but discrete impact on neurobehavioral development. 相似文献
88.
R Hunter R McLuskie D Wyper J Patterson J E Christie D N Brooks J McCulloch G Fink G M Goodwin 《Psychological medicine》1989,19(4):847-855
Single photon emission tomography (SPET) with the lipophilic blood flow marker 99mTc-hexamethyl propyleneamine oxime (99mTc-HMPAO) has been used to determine regional uptake of radiolabel into brain regions of patients with presenile Alzheimer's disease and Korsakoff's psychosis, and age-matched controls. Using occipital cortical uptake as reference area, the pattern of relative regional cerebral blood flow (rCBF) was determined in other cortical areas and basal ganglia. In Alzheimer's disease, reduction in rCBF occurred most strikingly in posterior temporal and parietal areas. By contrast, in Korsakoff's psychosis, posterior temporal rCBF was maintained, although there was a trend to reduced tracer uptake in other cortical areas. These impairments of flow were correlated with impairments of neuropsychological function. In Alzheimer's disease, left posterior temporal and left parietal regions in particular showed rCBF to be strongly correlated with most aspects of cognitive function. In Korsakoff's psychosis, however, impaired flow in frontal regions was correlated with impaired performance on tests of memory and orientation. The findings in Alzheimer's disease show quantitative parallels with those from studies using Positron Emission Tomography (PET), and extend our understanding of the relationship between cognition and regional brain function in dementia. The findings in Korsakoff's psychosis offer the first direct evidence linking frontal lobe dysfunction with the cognitive impairment seen in the disorder. 相似文献
89.
Leslie C. Grammer Loui Silvestri Irena M. Suszko Martha A. Shaughnessy Roy Patterson 《The Journal of allergy and clinical immunology》1983,72(2):160-167
The standardization procedures for polymerized ragweed (PRW) must evaluate activity of PRW with assessments that differ from those used for standard unmodified extracts. This is because PRW allergens are different from conventional ragweed extracts in that they are much greater in average molecular weight and much lower in allergenicity for equivalent immunogenicity. We have evaluated seven samples of PRW for three parameters: allergenicity as determined by cutaneous end point titration, molecular weight distribution as determined by Sephadex G-200 chromatography, and availability of antigen E (AgE) determinants as measured by the ability of an extract to inhibit AgE binding to antibody by using a modification of the Farr technique. The skin test titers and molecular weight profiles provide information as to the safety of a PRW preparation and antigen-binding inhibitory activity gives information about allergenicity and immunogenicity. Appropriate limits may be set for each of these parameters to standardize PRW for clinical use. 相似文献
90.
Two effects of HIV infection on human dendritic cells (DC) in vitro have been examined. The first was the stimulation of primary responses to HIV antigens in autologous lymphocytes from normal donors. When DC were exposed to HIV (10(4) TCID/10(5) cells) for up to 24 h before addition to autologous lymphocytes, a marked primary proliferative response to the virus was observed. No proliferative response was seen when the period of pre-exposure of DC to virus was extended. Cytotoxic T cells specific for HIV-infected target cells developed in stimulated cultures. The second effect of HIV infection of DC was to block responses to other antigens, such as alloantigens and the recall antigens tetanus toxoid and influenza virus. This inhibitory effect was only evident when the DC were exposed to HIV for longer than 24 h before being added to cultures. These in vitro studies suggest that infection of DC can produce both stimulatory and inhibitory responses in lymphocytes. Such effects operating through DC might underlie in vivo activity of HIV both in stimulating the proliferation of lymphocytes (e.g., in persistent generalised lymphadenopathy) and in the development of immunosuppression. 相似文献