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1.
R S Desowitz K K Shida L Pang G Buchbinder 《The American journal of tropical medicine and hygiene》1989,41(6):630-634
This study characterizes a Plasmodium berghei white rat model of P. falciparum malaria in the pregnant human. Seventy-day-old and 114-day-old female rats, given an infecting inoculum at time of mating, had higher parasitemias and a more severe anemia than age- and sex-matched controls. Under these experimental conditions, the parasitemia went to crisis in all animals and there were no fatal infections. In contrast, all animals died when the infection was initiated 7 days after conception, a timing that brought a coincidence of peak parasitemia and term. Pregnancy during the post-crisis subpatent period did not cause recrudescence. At the time of delivery, the parasitemia was consistently higher in the placental (crush smear) blood than in the peripheral (tail) blood. This difference was greatest in animals giving birth shortly before or 1-2 days after the parasitemic crisis. Very young, compact parasite forms predominated in the placental blood, whereas trophozoites predominated in the peripheral blood. 相似文献
2.
MRI of the brain in chronic carbon monoxide poisoning 总被引:3,自引:0,他引:3
We examined 13 patients with chronic carbon monoxide (CO) poisoning by magnetic resonance imaging (MRI); all of them had been in an explosion in a coal mine 25 years previously. Symmetrical globus pallidus lesions were observed in 12, as was degeneration of the white matter, with focal cortical atrophy. The temporal parietal and occipital lobes were usually affected, the parietooccipital region being the most frequently and extensively damaged. Of the 12 patients with white matter degeneration 7 had definitely asymmetrical cortical and subcortical lesions. There were 6 patients with dilated temporal horns, probably due to atrophy of the hippocampal gyri. A history of CO inhalation and an awareness of the typical distributions of lesions are important for recognition of the effects of CO poisoning, especially when patients are in the chronic stage. 相似文献
3.
4.
In intestinal anastomoses, local blood flow is one of the most important factors contributing to the success of the healing process. While submucosal local blood flow is maintained better in the colon than in the small intestine, the incidence of anastomotic leakage is higher in the former than in the latter. To resolve this conflict, we have examined differences in the reactivity of the intestinal segments toward the application of tension. Anastomosis was performed with a stapler on the jejunum, ileum, and colon of experimental dogs. The anastomotic sites were subjected to tensile loads applied in incremental steps to measure and compare local blood flow, measured by the hydrogen clearance method, in the submucosal layers of the anastomoses in these intestinal segments. The results of these comparative evaluations indicate that, at a tensile stress level of more than 4 g/mm2, local blood flow in the colon is significantly smaller than that in the jejunum and ileum. These findings were corroborated by microangiographical observations carried out during stress application. The microangiographical data suggest that the rate of filling of the contrast medium is lower with colonic anastomosis than with jejunal and ileal anastomoses. In addition, the intraluminal pressure of the colon was higher than that of the small intestine during the induced peristalsis. The different sensitivity of the local microcirculation systems of the intestinal segments to tension may thus be considered one of the factors accounting for the higher incidence of clinical suture failure in colonic than in small intestinal anastomoses. 相似文献
5.
温阳健心灵口服液治疗充血性心力衰竭的临床与实验研究 总被引:1,自引:0,他引:1
以煎剂形成筛选治疗CHF的处方,发现温阳益气方改善泵血功能的效果优于单纯益气和养阴益气的处方。根据前方制备的温阳健心灵口服液保持了原煎剂的疗效,并被毒理学试验证明毒性极低。动物药效学及临床试验发现该药不仅能改善心衰犬和病人的左室收缩功能,还能改善其舒张功能。除此,它还具有利尿作用和使PAWA、SVR和PVR下降的作用,这也是它抗心衰的机理之一。90例的临床观察(疗程2周)表明该药总有效率、近期治愈率和显效率分别达88.9%、7.4%和18.5%,其效与开搏通组无明显差异。 相似文献
6.
Sak, a murine protein-serine/threonine kinase that is related to the Drosophila polo kinase and involved in cell proliferation. 总被引:5,自引:0,他引:5
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C Fode B Motro S Yousefi M Heffernan J W Dennis 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(14):6388-6392
We have isolated murine cDNAs encoding two isoforms of a putative protein-serine/threonine kinase, designated Sak-a and Sak-b, which differ in their noncatalytic C-terminal ends. The kinase domain of Sak is related to the catalytic domains of the Drosophila polo, Saccharomyces cerevisiae CDC5, and murine Snk and Plk kinases, a family of proteins for which a role in controlling cell proliferation has been established (polo, CDC5) or implicated (Snk, Plk). Northern and in situ RNA analyses of Sak gene expression in mouse embryos and adult tissues revealed that expression was associated with mitotic and meiotic cell division. In addition, during embryogenesis, Sak expression was prominent in the respiratory and olfactory mucosa. The pattern of Sak expression and its sequence homology with the polo gene family suggest that the Sak kinase may play a role in cell proliferation. In support of this, cell growth was suppressed by expression of a Sak-a-antisense fragment in CHO cells. 相似文献
7.
采用免疫组织化学、免疫电子显微镜及高效液相结合放射免疫学方法,研究人和 Wistar 大鼠心包,结果表明:心包组织中存在 ANF 和 AngⅡ样物质。在采用兔抗 ANF 为抗体时,心包组织的间皮细胞存在明显的金粒子标记颗粒,间皮细胞是主要的内分泌细胞。心包组织存在 Ang Ⅱ和3种分子形式ANF.本研究提示.心包除已知功能外,尚存在重要的内分泌功能. 相似文献
8.
Honma K Abraham JL Chiyotani K De Vuyst P Dumortier P Gibbs AR Green FH Hosoda Y Iwai K Williams WJ Kohyama N Ostiguy G Roggli VL Shida H Taguchi O Vallyathan V 《Human pathology》2004,35(12):1515-1523
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders. 相似文献
9.
Simon D Vassina E Yousefi S Kozlowski E Braathen LR Simon HU 《The Journal of allergy and clinical immunology》2004,114(4):887-895
BACKGROUND: In several clinical studies, topical calcineurin inhibitors have been shown to be effective in the treatment of atopic dermatitis (AD). They target signaling pathways that control gene expression, particularly the expression of cytokines. OBJECTIVE: We examined the cellular infiltrate in skin lesions of 10 patients with AD and characterized the cytokine pattern expressed by the infiltrating cells before and after short-term topical therapy with tacrolimus 1% ointment. METHODS: Skin biopsies were examined for histologic alterations (hematoxylin and eosin staining), composition of the cellular inflammatory infiltrate (immunofluorescence), and cytokine expression (ribonuclease protection assay, ELISA, immunofluorescence) before as well as 1 and 3 weeks after initiation of tacrolimus therapy. For comparison, biopsies from nonlesional AD and normal skin were analyzed. Systemic immunologic effects were assessed by analyzing peripheral blood leukocytes (immunofluorescence) as well as in vitro stimulated pan-T-cell cytokine production (ELISA). RESULTS: All patients showed a significant improvement of their skin lesions associated with a marked regression of spongiosis, acanthosis, and density of the cellular infiltrate in the dermis. The last was a result of reduced infiltration of T cells, B cells, and eosinophils. In contrast, the numbers of mast cells did not change. Moreover, the expression of the T H 2 cytokines IL-5, IL-10, and IL-13 in CD4 + T cells was reduced after therapy. Interestingly, tacrolimus therapy was also associated with a reduction of CD8 + T cells expressing the T H 1 cytokine IFN-gamma. Furthermore, the numbers of epidermal CD1a + dendritic cells increased after treatment. In the peripheral blood, a decrease of granulocytes (eosinophils and neutrophils) but no changes in the distribution of lymphocyte subpopulations were noticed. CONCLUSION: Topical tacrolimus treatment has anti-inflammatory effects on AD skin as indicated by reduced infiltration of cytokine expressing inflammatory cells. No evidence for drug-induced systemic immunosuppression was obtained. 相似文献
10.
The function of the vaccinia hemagglutinin in the proteolytic activation of infectivity 总被引:3,自引:0,他引:3
The vaccinia virus hemagglutinin (HA) has specific affinity for the structural protein, VP37K. The nature of this affinity and its relationship to the function of the HA were analyzed using HA mutants. The VP37K reactive site of the HA molecule is located in its transmembrane region, and the vaccinia virus HA associates with the viral particle via the VP37K-HA affinity. The viruses possessing an HA with fusion inhibitor activity were largely of the low infectivity form, whereas the viruses that associated mutant HAs defective in the activity were of the high infectivity form. D1 mutant virus does not produce HA. When it was incubated with the HA of the IHD-J strain, the HA associated with the virus particle. The HA-loaded D1 mutant virus acquired a high affinity not only for chick erythrocytes but also for KB and Vero cells. At the same time, the infectivity for Vero cells was decreased. The original high infectivity was recovered by treatment with trypsin. The virion-associated vaccinia HA has two functions; the HA protects the infectivity of the virus by the fusion inhibitor activity and exhibits affinity against host cells. Vaccinia virus first adsorbs to the cell via HA, and then proteolysis of the HA activates the second adsorption site which seems to be the fusogenic site of the virus. Proteolytic activation represents removal of the fusion inhibitor activity of the HA. 相似文献