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991.
The effects of alaproclate and zimeldine on memory retrieval were examined in male Swiss Webster mice using a one-trial inhibitory avoidance task. All drugs were administered IP prior to the retention test 24 h after training. Both drugs were found to facilitate memory retrieval significantly in a dose-and time-dependent fashion that could not be explained in terms of non-specific effects of the drug (illness, lack of motility, etc.) at the time of the test. The temporal effects of alaproclate and zimeldine on memory closely followed their course of concentration of the drug within the blood stream. The facilitation of retrieval induced by alaproclate and zimeldine was blocked by the putative serotonergic receptor agonist quipazine but not blocked by the antagonist cyproheptadine. Pretreatment with quipazine alone in a group of animals trained to a shock level which normally results in high levels of suppression was not sufficient to produce memory impairment, suggesting that quipazine was probably antagonizing the facilitative effects of alaproclate and zimeldine directly, rather than overriding the facilitation through an indirect action on retrieval in general. The present results lend further support to the suggestion that serotonin plays a significant role in memory. 相似文献
992.
Undetectable levels of circulating interferon were found in 35 splenectomized patients and in 14 controls. In addition, no differences in virus, purified protein derivative (PPD), and phytohaemagglutinin (PHA) induced interferon production were observed between the patients and the controls. Virus induced lymphocyte transformation tended to be reduced after splenectomy, but only the herpes simplex virus (HSV) induced transformation index was significantly reduced in splenectomized patients without residual splenic tissue (P < 0.05). In contrast, the PHA lymphocyte transformation was unchanged in patients and controls. The number of natural viral antibodies in splenectomized patients did not differ from that of controls. Furthermore, there were no major differences in the magnitude of the titers of the sero-positive cases between the various groups. Thus, splenectomy does not interfere with interferon production in vitro, and as seen from natural viral antibodies, no impairment of humoral immunity was observed. The reduced HSV lymphocyte transformation may indicate an impaired lymphocyte function after splenectomy. 相似文献
993.
Richard H. Rahe Heikki Arajärvi Seija Arajärvi Sven Punsar Martti J. Karvonen 《Journal of psychosomatic research》1976,20(5):431-437
Coronary heart disease (CHD) is not equally prevalent in East vs West Finland. Substantially higher CHD rates are found in East Finland, and these higher rates are only partially explained by differences in physiological “risk factors” such as body mass, blood pressure, cigarette smoking, and serum cholesterol levels between persons in these two regions. Recent life changes magnitudes were assessed for representative groups of men living in these two areas of Finland. East Finns reported approximately 84% higher life change magnitude than West Finns. Subjects' life changes magnitudes were essentially unrelated to their physiological risk factors. The relatively increased life change levels seen for East Finns may constitute an environmental risk factor for CHD. 相似文献
994.
Sven G. Carlsson Helena Fagerberg Gran Horneman Carl-Philip Hwang Knut Larsson Margaretha Rdholm Joseph Schaller Bernt Danielsson Christer Gundewall 《Developmental psychobiology》1978,11(2):143-150
Short-term effects of different amounts of body contact between mother and newborn on human nursing behavior were studied. Extended contact immediately after parturition was related to an increase in affective components of maternal nursing behavior observed on postpartum Days 2 and 4. 相似文献
995.
996.
Presence of apoptotic and nonapoptotic disseminated tumor cells reflects the response to neoadjuvant systemic therapy in breast cancer
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Fehm T Becker S Becker-Pergola G Sotlar K Gebauer G Dürr-Störzer S Neubauer H Wallwiener D Solomayer EF 《Breast cancer research : BCR》2006,8(5):R60-7
Introduction
Neoadjuvant systemic therapy (NST) is an established strategy to reduce tumor size in breast cancer patients prior to breast-conserving therapy. The effect of NST on tumor cell dissemination in these patients is not known. The aim of this study was to investigate the incidence of disseminated tumor cells (DTC), including apoptotic DTC, in breast cancer patients after NST, and to investigate the correlation of DTC status with therapy response. 相似文献997.
Trichothecenes, such as deoxynivalenol (DON), are known to inhibit the protein synthesis in vitro by binding at the 60S subunit of eukaryotic ribosomes. Therefore, cells and tissues with high protein turnover, such as lymphocytes and the liver (albumin and fibrinogen synthesis), were suggested to react most sensitively to DON. However, to the author's knowledge this observation was not proven in vivo in pigs, which were regarded as the farm animals most susceptible to DON. A total of 31 castrated male, crossbred German Landrace x Pietrain pigs weighing approx. 40 kg were fed a DON contaminated diet (5.7 mg/kg) either acutely (one single dose) or subchronically (4 weeks) or a control diet (0.1 mg/kg). In addition, one group received an intravenous injection of 53 microg DON/kg LW. One hour after feeding, a "flooding dose" of the stable isotope l-[(2)H(5)]-phenylalanine (125 mg/kg LW) was given and frequent blood samples (permanent catheter) were collected over a 60 min period. The molar percent excess (MPE) of plasma free and protein-bound phenylalanine were measured by GC/MS. No differences could be observed in the plasma concentrations of total protein, albumin, fibrinogen and serum enzymes between the groups. On the other hand, fractional synthesis rates (FSR, %/d) of albumin were significantly decreased by 43%, 45% and 26% and FSR of lymphocytes declined by 27%, 19% and 24%, whereas fibrinogen was not significantly affected after subchronic or one single oral and intravenous DON exposure, respectively. Additionally, the absolute synthesis rate (ASR, g/d) of albumin and the proportion of albumin to total body protein synthesis were reduced in the same manner, whereas the albumin secretion time ranged between 6.8 and 34.4 min and was not affected by treatment. In conclusion, the flooding dose technique appeared to be suitable for distinguishing DON-related effects on the protein synthesis, while determination of plasma protein concentrations seemed not to be an appropriate parameter. 相似文献
998.
Holmquist-Mengelbier L Fredlund E Löfstedt T Noguera R Navarro S Nilsson H Pietras A Vallon-Christersson J Borg A Gradin K Poellinger L Påhlman S 《Cancer cell》2006,10(5):413-423
In neuroblastoma specimens, HIF-2alpha but not HIF-1alpha is strongly expressed in well-vascularized areas. In vitro, HIF-2alpha protein was stabilized at 5% O2 (resembling end capillary oxygen conditions) and, in contrast to the low HIF-1alpha activity at this oxygen level, actively transcribed genes like VEGF. Under hypoxia (1% O2), HIF-1alpha was transiently stabilized and primarily mediated acute responses, whereas HIF-2alpha protein gradually accumulated and governed prolonged hypoxic gene activation. Knockdown of HIF-2alpha reduced growth of neuroblastoma tumors in athymic mice. Furthermore, high HIF-2alpha protein levels were correlated with advanced clinical stage and high VEGF expression and predicted poor prognosis in a clinical neuroblastoma material. Our results demonstrate the relevance of HIF-2alpha in neuroblastoma progression and have general tumor biological implications. 相似文献
999.
Evertz S Dott W Eisentraeger A 《International journal of hygiene and environmental health》2006,209(5):423-434
Hazardous potential in industrial environments is normally assessed by means of immission-based sampling and analyses. This approach is not adequate, if effects of specific technical adjustments at machine tools or working processes on hygienic parameters should be assessed. This work has focused on the optimization of a manufacturing process (electrical discharge machining, EDM), with regard to risk reduction assessment. It is based on emission analyses rather than immision analyses. Several technical EDM parameters have been examined for their influence on air-based emissions. Worktools and workpieces used have a strong influence on aliphatic compounds and metals but not on volatile organic compounds (benzene, toluene, ethylene-benzene and xylene (BTEX)) and polycyclic aromatic hydrocarbons (PAHs) in air emissions. Increasing the dielectric (mineral oil) level above processing location decreases BTEX, chromium, nickel and PAH emissions. Aliphatic compounds, in contrast, increase in air emissions. EDM current used has a positive relationship with all substances analyzed in air emissions. Indicative immission concentrations, as can be expected under EDM conditions, are estimated in a predictive scenario. The results of this characterization give rise to an important conclusion in that risk assessment so far has been using incorrect parameters: total aliphatic compounds. Maximum level of chromium is reached long before limit values of aliphatic compounds are exceeded. Because of the fact that metals, like chromium, also have a higher hazardous potential, metal analysis should be introduced in future risk assessment. This experimental approach, that captures total emission of the electrical discharge machine, and is not solely based on immission values, has lead to a better understanding of the production process. This information is used to extract recommendations regarding monitoring aspects and protection measures. 相似文献
1000.
Nilsson SE 《Acta ophthalmologica Scandinavica》2006,84(4):452-65; 451
PURPOSE: This Acta Ophthalmologica Award and Gold Medal Honorary Lecture (the Lundsgaard Gold Medal Honorary Lecture) reviews some of the work I have carried out with my mentors and many of my wonderful collaborators and research students over more than 40 years, also including related work by other groups. It concentrates on the basic electrophysiology and ultrastructure of the retina and the retinal pigment epithelium (RPE), as well as covering basic and clinical aspects of the cornea, contact lenses, age-related macular degeneration (AMD) and hereditary diseases. METHODS: The review describes research performed using light and electron microscopy, basic and clinical electrophysiology, genetics and biochemistry in animal experiments and in research on patients. It also outlines clinically used techniques, such as laser and photodynamic treatment and scanning laser ophthalmoscopy. RESULTS: The paper reports on the following subjects: the mechanisms behind some of the electrical potentials originating in the retina and the RPE and the use of these potentials in hereditary diseases; corneal receptors for lectins and presumably for bacteria; the turnover of the photoreceptor outer segment and the formation of lipofuscin, including the relation of these processes to AMD; certain treatments for AMD, and hereditary degenerations in animal models, such as the RPE65 gene mutation in Briard dogs, which makes them a model of Leber's congenital amaurosis. The dogs are now treated successfully with gene therapy in the USA, and a clinical trial is in preparation. CONCLUSIONS: During the last 40 years we have had the good fortune to experience a dramatic growth in knowledge and understanding within ophthalmic science of basic mechanisms. Huge progress has been made in diagnostics and clinical ophthalmological treatments, much to the benefit of our patients. Even a small contribution made by my group to these developments has been well worth the effort, particularly as scientific work is not just deeply satisfying: it is also fun! 相似文献