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1.
Frank G. Holz Caren Bellmann Heimo Steffen Bernhard Nölle Jens Huober Hermann Krastel Evangelos Alexandridis 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1997,94(5):337-342
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang
am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart
eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri.
Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben.
Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina.
Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische
St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente,
der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden.
Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein.
Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression
identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in
Betracht.
相似文献
2.
Mirjam Gross-Jendroska Christina J Flaxel Steve D Schwartz Frank G Holz Fred W Fitzke Veit-Peter Gabel Alan C Bird 《Clinical & experimental ophthalmology》1998,26(4):311-317
Purpose: To flatten pigment epithelial detachments (PED) cue to age-related macular degeneration in an attempt to visualize the underlying choroidal neovascularization by fluorescein angiography (FA) and reveal a treatment target. Methods: Nine patients with PED received intravitreal gas injections via the pars plana and postured face down. Fluorescein angiograms were obtained before and after gas injection. In two patients, retinal scotopic sensitivity was also measured. Results: Eight patients demonstrated change in the shape and size of the PED following gas injection. Four patients showed a better delineation of underlying structures on FA. Three patients had focal laser treatment to the newly visible choroidal neovascular complex, but this was successful in only one patient with flattening of the PED. Conclusion: Pigment epithelial detachments can be modified by intravitreal gas injection in some patients, but this treatment did not have a major impact on overall outcome or management. 相似文献
3.
Cell physiology of cAMP sensor Epac 总被引:9,自引:0,他引:9
George G. Holz Guoxin Kang Mark Harbeck Michael W. Roe Oleg G. Chepurny 《The Journal of physiology》2006,577(1):5-15
Many animal studies and human epidemiological findings have shown that impaired growth in utero is associated with physiological abnormalities in later life and have linked this to tissue programming during suboptimal intrauterine conditions at critical periods of development. However, few of these studies have considered the contribution of the placenta to the ensuing adult phenotype. In mammals, the major determinant of intrauterine growth is the placental nutrient supply, which, in turn, depends on the size, morphology, blood supply and transporter abundance of the placenta and on synthesis and metabolism of nutrients and hormones by the uteroplacental tissues. This review examines the regulation of placental nutrient transfer capacity and the potential programming effects of nutrition and glucocorticoid over-exposure on placental phenotype with particular emphasis on the role of the Igf2 gene in these processes. 相似文献
4.
5.
Stanley G. Rane George G. Holz IV Kathleen Dunlap 《Pflügers Archiv : European journal of physiology》1987,409(4-5):361-366
Dihydropyridine (DHP) calcium channel antagonists, which inhibit the slowly inactivating or L-type cardiac calcium (Ca) current, have been shown to be ineffective in blocking45Ca influx and Ca-dependent secretion in a number of neuronal preparations. In the studies reported here, however, the antagonist DHP nifedipine inhibited both the L-type Ca current and potassium-evoked substance P (SP) release from embryonic chick dorsal root ganglion (DRG) neurons. These results suggest that, in DRG neurons. Ca entry through L-type channels is critical to the control of secretion. The inhibition of Ca current by nifedipine was both voltage and time-dependent, significant effects being observed only on currents evoked from relatively positive holding potentials maintained for several seconds. As expected from these results, nifedipine failed to inhibit L-type Ca current underlying the brief plateau phase of the action potential generated from the cell's normal resting potential; likewise, no significant effect of the drug was observed on action potential-stimulated SP release evoked by electrical field stimulation. The results of this work are discussed in terms of an assessment of the role of L-type Ca channels in neurosecretion.This work was supported by United States Public Health Service Grant NS16483 (KD) and by a USPHS Postdoctoral Fellowship (SGR) 相似文献
6.
Clark P. Holz P. Booth R. Jakob-Hoff R. Cooper D.W. Boardman W.S. Parry B.W. Norman R.J. 《Comparative clinical pathology》2003,12(1):11-16
Blood was collected from 31 Parma wallabies from five different captive populations. The morphology of erythrocytes, leucocytes
and platelets was similar to that previously described for macropodids. The effects of location (population), anaesthesia
and analyser on the haematological characteristics of the wallabies were considered. Location had an affect on many of the
values, anaesthesia affected some of the leucocyte values, and analyser had little effect.
Received: 22 November 2002 / Accepted 13 February 2003
Acknowledgements We thank Mrs R. Power, Ms S. Bayliss, Ms T. Smith and Mrs P. Slack for technical assistance, Mr D. Hopcroft for assistance
with electron microscopy and Mr D. Hedderly for performing the statistical analyses. 相似文献
7.
Sinkus R Lorenzen J Schrader D Lorenzen M Dargatz M Holz D 《Physics in medicine and biology》2000,45(6):1649-1664
MR elastography is a novel imaging technique for the visualization of elastic properties of tissue. It is expected that this method will have diagnostic value for the clarification of suspicious breast lesions. Low-frequency mechanical waves are coupled into the tissue and visualized via an MR sequence which is phase-locked to the mechanical excitation. Commonly, elasticity is assumed to be isotropic and reconstruction is performed in only two dimensions. The technique is extended to three dimensions such that the entire symmetric elasticity tensor is assessed. This is achieved by measuring different phases of the mechanical wave during one oscillatory cycle. Thereby it is possible to provide information about the anisotropy of the elasticity tensor. Finite-element simulations as well as phantom experiments are performed to demonstrate the feasibility of the method. Initial clinical results of a breast carcinoma are presented. The analysis of the eigenvalues of the elasticity tensor support the hypothesis that breast carcinoma might exhibit an anisotropic elasticity distribution. The surrounding benign tissue appears isotropic. Thereby new and additional diagnostic information is provided which might help in distinguishing between benign and malignant breast diseases. 相似文献
8.
Inhibition of lysosomal degradative functions in RPE cells by a retinoid component of lipofuscin 总被引:4,自引:0,他引:4
Holz FG Schütt F Kopitz J Eldred GE Kruse FE Völcker HE Cantz M 《Investigative ophthalmology & visual science》1999,40(3):737-743
PURPOSE: To investigate the effect of the lipofuscin component N-retinylidene-N-retinylethanolamine (A2-E) on degradative functions of lysosomes in human retinal pigment epithelial (RPE) cells and to evaluate its mechanism of action. METHODS: A2-E was coupled to low-density lipoprotein (LDL). Human RPE cell cultures were loaded with the A2-E/LDL complex, and controls were run with medium containing LDL alone. To determine whether A2-E accumulated in lysosomes, cells were fractionated in a Percoll gradient, and protein degradation was determined by metabolic labeling and measurement of the release of low-molecular-weight radioactivity. Lysosomal degradation was distinguished from nonlysosomal degradation by inclusion of NH4Cl in the medium. The metabolism of sulfated glycosaminoglycans was studied by radiosulfate incorporation in pulse-chase experiments. Intralysosomal pH was determined using a fluorescent lysosomotropic pH indicator. RESULTS: A2-E accumulated almost exclusively in the lysosomal compartment. Lysosomal protein degradation was reduced in a dose-dependent fashion in A2-E-treated cells. The selectivity of A2-E on lysosomal function was demonstrated by its lack of effect on degradation of extralysosomal protein. Lysosomal glycosaminoglycan catabolism of RPE cells was also strongly inhibited by A2-E. Lysosomal pH was increased by A2-E. CONCLUSIONS: The findings indicate that accumulation of A2-E in RPE cells interferes with lysosomal functions as exemplified by its inhibitory effect on protein and glycosaminoglycan catabolic pathways. The quaternary amine character of the A2-E apparently causes a perturbation of the acidic intralysosomal milieu, resulting in diminished hydrolase action and consequent accumulation of undegraded material. Such mechanism could be operative in retinal diseases associated with excessive lipofuscin accumulation including age-related macular degeneration. 相似文献
9.
The most frequent localization of fractures in elderly patients are the metaphysis of the distal radius, the metaphysis of the proximal humerus and the metaphysis of the proximal femur. Displaced fractures of the distal radius should be reduced anatomically with a broad indication for surgery. A unilateral frame is the method of choice in multi-fragmentary and articular fractures although this procedure carries some disadvantages. Displaced proximal fractures of the head of the humerus should be reduced and fixed operatively. Minimal invasive procedures like tension band fixation lead to better results than fixation with plates. Non-reducible four-part fractures require primary prosthetic replacement. If standard procedures in the treatment of distal fractures of the humerus fail because of severe osteoporosis, tension band fixation may allow functional post-operative treatment. Fractures of the trochanteric region of the femur can be stabilized by several dynamic standard implants that permit early weight bearing. If fixations should fail, corrective osteotomies or changing of implants--in rare cases combined with bone cement--may be necessary. Each case requires an individualized procedure in order to ensure optimal restoration of function and mobility in elderly patients. 相似文献
10.