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31.
32.
R. L. Mittal 《International orthopaedics》1987,11(3):189-192
Summary Resistant club foot remains an unsolved problem because of the complex aetiological and pathological factors, and is still seen quite frequently, especially in developing countries. The posteromedial skin contracture is a potent deforming force which is responsible for many failures or relapses. I report the results of an operation in which a rotation skin flap was combined with an extensive soft-tissue release. The age of the children was from 9 months to 10 years. The follow-up period was from one to 9 years with an average of 43 months, and in 50 cases for more than 5 years. I consider that the outcome has been excellent or good in 94 out of 100 feet.
Résumé Le pied bot invétéré demeure un problème mal résolu en raison de la complexité des facteurs étiologiques et anatomiques et il est encore bien souvent rencontré, notamment dans les pays en voie de développement. La rétraction cutanée postéro-interne représente un puissant élément de la déformation, qui est responsable de bon nombre d'échecs ou de récidives. Nous rapportons les résultats d'une opération qui associe un lambeau cutané de rotation à la libération des parties molles. L'âge des enfants était compris entre neuf mois et dix ans. Le recul est de un à neuf ans, avec une moyenne de 43 mois. Cinquante enfants ont été suivis plus de cinq ans. Les résultats sont excellents ou bons dans 94% des cas.相似文献
33.
Ineffectiveness of organic calcium channel blockers in antagonizing long-term potentiation 总被引:1,自引:0,他引:1
Evidence has accumulated suggesting that the presence of calcium is critical for development of hippocampal long-term potentiation (LTP). However, there is a paucity of information about whether calcium's role in LTP is pre- or postsynaptic. In the present study, we examined the effectiveness of nitrendipine, verapamil, flunarizine and the benzodiazepine diazepam in: blocking voltage-dependent calcium channels; blocking synaptic transmission; and preventing development of LTP. Using the in vitro slice preparation, we obtained intracellular and extracellular recordings from guinea pig hippocampal CA1 pyramidal cells. At the cellular level, all 4 drugs were ineffective in blocking voltage-dependent calcium spikes (TTX resistant) and the calcium-dependent afterhyperpolarization. Verapamil and diazepam appeared to antagonize synaptic transmission, as reflected in smaller population spike amplitudes. Development of long-term potentiation was not affected by the presence of verapamil, flunarizine and diazepam. Nitrendipine appeared to reduce the percentage of slices exhibiting LTP; however, ethanol, the vehicle used to dissolve nitrendipine, was shown in separate experiments to reduce the percentage of slices exhibiting LTP. These results suggest that neither the organic calcium channel blockers--nitrendipine, verapamil, and flunarizine--nor micromolar concentrations of diazepam are potent blockers of extrasynaptic voltage-sensitive calcium channels in hippocampus. They thus cannot be used to demonstrate a specific pre- or postsynaptic calcium role in LTP. 相似文献
34.
旋磁场对胆结石病人胆汁中胆红素、钙、胆固醇和pH的影响 总被引:1,自引:0,他引:1
目的 探讨旋磁场与大面积静磁场对置对胆结石病人胆汁中总胆红素(BIT)、直接胆红素(BID)、间接胆红素(BII)、钙(Ca)、胆固醇(CH)和pH的影响。方法 旋磁组30例,测定旋磁处理前后65对胆汁样本。空白对照组15例,留取前后30对胆汁样本。将直径12mm圆形稀土永磁片110块,表面磁感应强度210mT,分别间隔10mm贴于210mm×220mm铁皮上形成一个大面积磁板与旋磁头表面静磁感应强度160mT,旋转平均表面磁感应强度100mT呈异名极对置,磁板置肝区背侧,旋磁头置剑突下处理40min。结果 旋磁组胆结石病人胆汁(n=65):经旋磁场与磁板对置处理前减去处理后差值的x±s和t值分别为BIT41.81±93.52、3.59;BID 13.57±43.70、2.46;BII28.27±61.67、3.32;Ca 0.19±0.31、4.87;CH0.12±0.29、3.36;pH 0.01±0.27、0.30。除pH外,其余各项指标P值均<0.05。对照组胆汁(n=30):间隔时间前后差值的x±s和t值分别为BIT4.42±22.05、1.14;BID2.40±12.37、1.06;BII2.52±46.27、0.30;Ca0.01±0.18、0.50;CH0.03±0.15、0.94;pH 0.009±0.06、0.84。P值均>0.05。结论 在本项磁场类型、强度和时间处理条件下,旋磁场与磁板对置能明显影响胆结石病人胆汁中的BIT、BID、BII、Ca和CH的浓度变化,且有显著降低的作用。 相似文献
35.
36.
A. Purohit S. Laffer† C. Metz-Favre A. Verot F. Kricek‡ R. Valenta† G. Pauli 《Clinical and experimental allergy》2005,35(2):186-192
BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity. 相似文献
37.
Skoug John W. Borin Marie T. Fleishaker Joseph C. Cooper Anne M. 《Pharmaceutical research》1991,8(12):1482-1488
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets. 相似文献
38.
The toxic effects of nitroquine-dapsone compound(NQD)in mice and dogs were studied.The therapeutic index of NQDin mice is 1911,the greatest among the 6 antimalarials tested.Thetoxic effects of NQD(50 mg/kg/day for 3 days per os)and nitro-quine in dogs were manifested by injuries on the adrenal cortexand intestinal epithelium.When folic acid(4 mg/kg/day for 4 days)or calcium leucovorinum(0.3 mg/kg/day for 4 days)were usedconcomitantly with NQD,the death rate and the incidence of dia-rrhea in the toxicated dogs were greatly reduced,the injury on theintestinal epithelium was much milder,and the goblet cells weremuch more numerous than those without treatment.The results suggestthat folic acid and calcium leucovorinum can protect the undifferen-tiated cells in the intestinal crypts from being injured by NQD. 相似文献
39.
In vivo electrochemical methods were employed to study the potassium (K+-evoked release of monoamines from the cerebellum of the chloral hydrate anesthetized rat. K+-evoked releases were elicited using micropipette-Nafion-coated graphite epoxy electrode arrays in the granule/Purkenje cell layer, molecular layer, and white matter. These recorded releases were generally found to be reversible, moderately dose-dependent, and reproducible. However, the temporal dynamics of the releases were different for the cell layer versus molecular layer records. Releases were infrequently observed in cerebellar white matter, an area which is relatively devoid of monoamine containing terminals. The signals recorded from the cell and molecular layers were significantly attenuated by pretreatment with nomifensine, a potent catecholamine reuptake blocker, significantly prolonged the K+-evoked signals observed in both the granule/Purkenje cell and molecular layers. These data, taken together with earlier reports on the electrophysiological responses to activation of cerebellar noradrenergic inputs, support the conjecture that in vivo electrochemical recording methods have the sensitivity and spatial resolution for studies of functional monoamine release from brain regions that have a diffuse or laminated monoamine innervation. 相似文献
40.
C. COLETTE M. C. GOUTTEBEL† L. H. MONNIER B. SAINT-AUBERT† H. JOYEUX† 《European journal of clinical investigation》1986,16(4):271-276
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献