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151.
152.
Jörg Bohmeyer Andreas Heller Christine Hartig Margaretha Westenberger-Treumann Hans Huchzermeyer Heinz-Günter Otte Rudolf Stadler 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1996,47(2):106-108
Zusammenfassung
Trotz der H?ufigkeit der Erkrankung liegen nur wenige gesicherte Erkenntnisse über die ?tiologie der chronischen Urtikaria
vor. Bei 10 Patienten, bei denen keine anderweitige Ursache für die Erkrankung ermittelt werden konnte, führten wir eine Gastroskopie
durch. Bei 8 der 10 Patienten konnte eine Besiedlung der Magenschleimhaut mit Helicobacter pylori gesichert werden. Die Urtikaria
heilte innerhalb weniger Tage bei allen Patienten ab, nachdem wir eine Therapie mit Amoxicillin und Omeprazol einleiteten.
Eingegangen am 6. Februar 1995 Angenommen am 12. Mai 1995 相似文献
153.
In order to define precisely the relation between descending monoaminergic systems and the motor system, we measured in the ventral horn of spinal cord of adult rats the variations of extracellular concentrations of 5-HT, 5-HIAA, DA and MHPG. Measurements were performed during rest, endurance running on a treadmill, and a post-exercise period, with microdialysis probes implanted permanently for 45 days. We found a slight decrease in both 5-HT and 5-HIAA during locomotion with a more marked decrease during the post-exercise period compared to the mean of rest values. In contrast, the concentration of DA and MHPG increased slightly during the exercise and decreased thereafter. These results, when compared with those of a previous study, which measured monoamines in the spinal cord white matter [C. Gerin, D. Bécquet, A. Privat, Direct evidence for the link between monoaminergic descending pathways and motor activity: I. A study with microdialysis probes implanted in the ventral funiculus of the spinal cord, Brain Res. 704 (1995) 191–201], highlight the complex regulation of the release of monoamines that occurs in the ventral horn. 相似文献
154.
Christine D. Peralta George P. Danko Ronald C. Johnson 《Alcoholism, clinical and experimental research》1995,19(4):964-968
Four hundred and eight respondents, who did or did not know persons close to themselves with alcohol problems, from four different racial/ethnic groups (with one group, Filipinos, categorized in terms of whether they were born in the Philippines or in the US.) rated the importance of 19 different causes of problem alcohol use and 22 different means of overcoming problem alcohol use. Rank-order correlations across sexes, persons differing in exposure to problem drinkers, and ethnic groups were nearly all in the 0.90's regarding causation. Correlations of Caucasians' ratings with those of other groups were high, but only in the 0.60's and 0.70'9, chiefly because Caucasians were more prone to regard problem alcohol use as hereditary and as a disease, and less likely to believe problem use to result from social factors. All across-group correlations concerning beliefs about the effectiveness of means of overcoming problems were in the 0.90's. Some of the means of treatment regarded most highly by all groups have not been demonstrated to be effective. 相似文献
155.
Lakshmi Pendyala Patrick J. Creaven Robert Huben Dominique Tremblay Christine Bertagna 《Cancer chemotherapy and pharmacology》1988,22(1):69-76
Summary The pharmacokinetics of total radioactivity and unchanged drug were studied in patients receiving Anandron (Nilutamide, RU 23908) after a single dose of [14C] Anandron and after q12 h dosings of unlabelled drug for 2–7 weeks. The results indicate that the radioactivity in plasma consists of unchanged drug and metabolites. The plasma decay of Anandron after the absorption phase was biexponential in all patients, with the terminal phase half-life ranging from 23.3–87.2 h. The plasma decay of total radioactivity after the absorption phase was biexponential in 3/12 and monoexponential in 9/12 patients. The calculated terminal phase half-lives for total radioactivity after [14C] Anandron were 34.5–137.3 h. The AUC0– of the unchanged drug in plasma represented 23%–38% of the AUC0– of total radioactivity. Urinary radioactivity consisted primarily of metabolites, the majority of which were chloroform-nonextractable. Urinary excretion of radioactivity at 120 h ranged from 49%–78% of the administered dose; the unchanged Anandron (at 72 h) was 0.6%–1.3% of the dose. In three patients studied, the fecal excretion of Anandron was 1.4%–7.0%. Steady-state plasma levels (4.4–8.5 g/ml) were attained within approximately 2 weeks from the initiation of twice daily dosing of Anandron. When the plasma pharmacokinetics of radioactivity and unchanged drug after the first single dose were compared with that during steady state, AUC0–12 h of unchanged Anandron during steady state was significantly higher than the AUC0– after the first single dose, suggesting that the plasma clearance of Anandron is lowered upon chronic administration of the drug, assuming that the bioavailability is constant. 相似文献
156.
Summary Rat-liver microsomes and NADPH could reduce Adriamycin, epirubicin and daunorubicin to their free radical forms, which enhanced peroxidation of microsomal lipids less than 2-fold in air but 3- to 5-fold at a pO2 of 4 mm Hg. Mitoxantrone was not reduced by microsomes and had no effect on microsomal peroxidation. Daunorubicin caused more lipid peroxidation than similar concentrations of either Adriamycin or epirubicin, which were equally efficient. In each case peroxidation was iron-dependent and could be catalysed by ferritin. The antioxidants -carotene and -tocopherol inhibited lipid peroxidation at low or high pO2. The dose-for-dose difference in the cardiotoxicity of epirubicin compared with Adriamycin is not explained by its effect on microsomal lipid peroxidation. However, the lower incidence of cardiotoxicity with mitoxantrone may be a consequence of its inability to form free radical species and promote lipid peroxidation. 相似文献
157.
Localization of SNARE proteins and secretory organelle proteins in astrocytes in vitro and in situ 总被引:1,自引:0,他引:1
Wilhelm A Volknandt W Langer D Nolte C Kettenmann H Zimmermann H 《Neuroscience research》2004,48(3):249-257
Astrocytes are capable of regulated release of messenger molecules. Astrocytes cultured from new born rodent brain express a variety of classical presynaptic proteins. We investigated the question whether the capability to express synaptic proteins in culture was a feature only of immature astrocytes, and whether these proteins were also expressed by astrocytes in situ. Experiments were performed with transgenic mice expressing the enhanced green fluorescent protein under the control of the human glial fibrillary acidic protein promoter. Using double fluorescence and astrocytes cultured from 1 to 16 day-old animals we show that the astrocytic expression of synaptic proteins in culture is invariant of the age of donor animals. Culturing can induce the astrocytic expression of specific synaptic proteins such as SV2, synaptophysin and SNAP-25. Astrocytes in brain sections of 1-16 day-old animals revealed a punctuate immunofluorescence for secretory carrier membrane protein (SCAMP), SNAP-23, synaptobrevin II, and cellubrevin, to a minor extent for SNAP-25 and synaptophysin, and none for SV2. Our results demonstrate that cultured astrocytes express synaptic proteins not present in situ. Nevertheless, astrocytic organelles in situ are equipped with molecules that could be involved in regulated exocytosis of messenger substances. 相似文献
158.
Macrophage response to peripheral nerve injury: the quantitative contribution of resident and hematogenous macrophages 总被引:6,自引:0,他引:6
Mueller M Leonhard C Wacker K Ringelstein EB Okabe M Hickey WF Kiefer R 《Laboratory investigation; a journal of technical methods and pathology》2003,83(2):175-185
Whereas local microglial cells of the CNS rapidly respond to injury, little is known about the functional role of resident macrophages of the peripheral nervous system in nerve pathology. Using bone marrow chimeric rats, we recently identified individual resident endoneurial macrophages that rapidly became activated after nerve injury. However, the extent of local macrophage activation and its quantitative contribution to the total macrophage response is unknown. We now have created chimeric mice by transplanting bone marrow from green fluorescent protein (GFP)-transgenic mice into irradiated wild-type mice, allowing easy differentiation and quantification of hematogenous and resident endoneurial macrophages. After sciatic nerve crush injury, both GFP(-) and GFP(+) resident macrophages, the latter having undergone physiological turnover from the blood before injury, rapidly underwent morphological alterations and increased in number. Proliferating GFP(-) and GFP(+) resident macrophages were abundant and peaked 3 days after injury. A major lesion-induced influx of hematogenous macrophages with a disproportionate increase of GFP(+) macrophages was not observed until Day 4. Throughout all time points examined, GFP(-) resident macrophages were strikingly frequent, reaching maximum numbers 9.5-fold above baseline. There was also a notable proportion of GFP(-) resident endoneurial macrophages phagocytosing myelin and expressing major histocompatibility complex class II. Our results demonstrate for the first time that the rapid response of resident endoneurial macrophages to nerve injury is quantitatively important and that local macrophages contribute significantly to the total endoneurial macrophage pool during Wallerian degeneration. 相似文献
159.
160.
Since previous studies showed that calcium uptake by synaptosomes from rodents declines with aging [30], the subsynaptosomal distribution of calcium was determined with the disruption method of Scott et al. [37]. Calcium uptake by the mitochondrial (digitonin-resistant) and non-mitochondrial (digitonin-labile) compartments, as well as total uptake, were determined at 2, 5 and 10 min. After a 10 min incubation under resting conditions (5 mM-KCl), total calcium uptake decreased at 10 months (−14.6%) and 30 months (−33.0%) of age; mitochondrial calcium uptake increased by 10 months (+11.2%) but declined by 30 months (−17.5%); the nonmitochondrial calcium compartment declined at 10 (−34.7%) and 30 (−43.4%) months when compared to the 3 month old control. With potassium depolarization (31 mM-KCl), total calcium uptake declined from 100% (3 months) to 73.8% (10 months) or 53.0% (30 months); mitochondrial calcium uptake declined from 100% (3 months) to 85.6% (10 months) or 68.4% (30 months); non-mitochondrial calcium uptake decreased at 10 (−34.3%) and 30 (−57.7%) months of age when compared to 3 months (100%). The deficits in calcium homeostasis are not due to changes in synaptosomal volumes or to diminished membrane potentials, as assessed by tetraphenylphosphonium ion accumulation. 3,4-Diaminopyridine partially reversed the alterations in total, mitochondrial and non-mitochondrial calcium uptake by synaptosomes from aged mice. 相似文献