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21.
The growth and development of vegan children 总被引:1,自引:0,他引:1
The results of prospective study on the growth and diets, estimated from 7-day weighed food intake records, of 20 life vegan children (aged 5.8–12.8 years) are presented. The growth and development of the children were normal but they tended to be lighter in weight and exceptionally lean compared with standards. Heights were around the median of the Tanner-Whitehouse standards but were lower than the medians recently proposed by the Department of Health. Energy intakes were similar to those reported in children of the same age in the general population, but dietary fibre intakes were very high which may have influenced the digestible energy. Sugar provided an average 15.6% of the dietary energy and this was supplied mainly by fruit and fruit juice. Mean fat intakes were close to the dietary reference values. Daily intakes of essential nutrients generally met the amounts recommended, with the exceptions of calcium and vitamin B12 . Many children received supplementary sources of vitamin B12 and only two children had intakes below the lower recommended nutrient intake. Intakes of saturated fatty acids were low and those of linoleic acid were high. The ratio of linoleic/α-linolenic acid was high. As docosahexaenoic acid is absent from vegan diets, it is suggested that vegans should use oils with a lower ratio of linoleic/α-linolenic acid. Future studies should also consider the influence of a vegan diet on retinal function. None of the children was immunized against whooping cough and 11 had not been immunized against polio: 16 of the children had suffered from whooping cough. Future studies need to take into account factors other than diet when assessing the health of vegans. The results of this study show that children can be successfully reared on a vegan diet providing sufficient care is taken to avoid the known pitfalls of a bulky diet and vitamin B12 deficiency. 相似文献
22.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
23.
24.
T. E. CEDERHOLM A. B. BERG E. K. JOHANSSON K. H. HELLSTRÖM J. E. W. PALMBLAD 《European journal of clinical investigation》1994,24(9):615-620
Abstract Essential fatty acid (FA) deficiency, which may accompany protein-energy malnutrition (PEM), has been associated with impaired inflammatory reactions. We evaluated this relationship by analysing FA profiles and delayed cutaneous hypersensitivity in 20 malnourished elderly non-cancer patients and in 20 age-matched control patients. As indicated by serum cholesterol and serum triglycerides, the lipid levels were decreased by about one-third in the subjects with PEM. In comparison with the controls, there was a reduction in the ω 3 FA (e.g. eicosapentanoate) in total serum lipids (mgl-1 ) and serum phospholipids (%) of 40% and 47%, respectively. Reductions in serum ω 6 FA (e.g. linoleate and arachidonate) levels corresponded to the drop in total FA concentrations (30%). The cutaneous hypersensitivity was impaired in 14 of the malnourished patients. The magnitude of the skin reaction was positively correlated ( P < 0·05) to the concentrations of eicosapentanoate in serum lipids and serum phospholipids, as well as to the linoleate concentration in total serum lipids. Six of the malnourished patients took part in a nutritional intervention programme for 3 months. In parallel with an improvement in the nutritional status there was a 35% increase ( P < 0·05) in the total ω 3 FA serum concentration. Negative skin tests became positive and the median skin induration enlarged threefold ( P < 0·05). Thus, deficiency of ω 3 FA might be one factor contributing to cutaneous anergy in elderly malnourished patients. 相似文献
25.
目的 :探讨山东、湖北合欢皮与山合欢皮的内在质量。方法 :用氨基酸自动分析仪和原子吸收分光光度计对山东、湖北合欢皮与山合欢皮的氨基酸及部分微量元素进行分析。结果 :山东、湖北合欢皮与山合欢皮均含大量人体必需氨基酸和微量元素。结论 :为评价产地对合欢皮质量的影响以及合欢皮与山合欢皮的质量差异提供了依据 相似文献
26.
27.
术中输注氨基酸对硬膜外阻滞复合全麻开胸手术患者围术期体温的影响 总被引:2,自引:0,他引:2
目的评价术中输注氨基酸对硬膜外阻滞复合全麻食管癌和贲门癌手术患者围术期深部体温和代谢的影响。方法择期食管癌和贲门癌手术患者21例,ASAⅠ或Ⅱ级,随机分为3组(n =7):从麻醉诱导开始至手术结束,分别静脉输注氨基酸混合液240kJ·h-1(AA组)、等容量乳酸钠林格氏液(LR组)、葡萄糖溶液240kJ·h-1(GLU组)。麻醉诱导前至术后2h每5分钟测定鼓膜温度,于麻醉诱导前即刻、手术开始后1h和术后1h检测指尖血糖,采用4分表法评价术后2h内寒战的发生情况,采用间接测热仪测定术前与术后氧耗。结果与麻醉诱导前即刻比较,术后30min LR组和GLU组氧耗降低,AA组氧耗升高(P<0.01),术后2h LR组、GLU组鼓膜温度降低(P<0.05),AA组差异无统计学意义(P>0.05);与LR组和GLU组比较,AA组术后2h内寒战发生例数减少(P< 0.05),术后30min氧耗增多(P<0.05),LR组与GLU组比较差异无统计学意义(P>0.05)。结论硬膜外阻滞复合全麻开胸手术患者术中静脉输注氨基酸可通过提高基础代谢率,缓解围术期深部体温降低,减少术后寒战发生,而输注葡萄糖不产生此效应。 相似文献
28.
PEMMARAJU NARASIMHA RAO JAMES E. BURDETT JAMES W. CESSAC CECIL M. DiNUNNO DOROTHY M. PETERSON HYUN K. KIM 《Chemical biology & drug design》1987,29(1):118-125
The DL-arylamino acid ethyl ester derivatives of β-(3-pyridyl)-DL-alanine, and β-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide. 相似文献
29.
Free amino acid concentrations of CSF were measured in bacterial meningitis, aseptic meningitis, meningoradiculitis Garin-Bujadoux-Bannwarth, multiple sclerosis, carcinomatous meningitis, and controls. Almost all CSF amino acids were highly elevated in bacterial but not in aseptic meningitis, meningoradiculitis Garin-Bujadoux-Bannwarth or carcinomatous meningitis thus providing a laboratory tool for their differential diagnosis. In carcinomatous meningitis the amino acid pattern indicates metabolic activity of tumor cells. Minimal alterations were found in multiple sclerosis which have no diagnostic value. 相似文献
30.
Taurine has been proposed as an inhibitory neurotransmitter or neuromodulator in the vertebrate central nervous system. Within the spinal cord, taurine has been shown to have a direct inhibitory effect on spinal neurons and to have a selective antinociceptive effect on chemically induced nociception. Although sufficient data exists to suggest that taurine plays a neurotransmitter or neuromodulatory role in the spinal cord, it is not known whether this amino acid is present in axon terminals nor if this amino acid has a unique pattern of distribution within spinal tissue. To address these questions a monoclonal antibody against taurine was employed to localize taurine-like immunoreactivity in the dorsal horn of the rat spinal cord by using both light and electron microscopic techniques. Taurine-like immunoreactivity was most dense and most prominent in laminae I and II of the dorsal horn. A moderate amount of immunoreactivity was also present in laminae VIII and IX and X while the remaining laminae were only lightly stained. In laminae I and II taurine-like immunostaining was evident within neuronal cell bodies, dendrites, myelinated and unmyelinated axons, axon terminals, and astrocytes and their processes. Cell counts of these two laminae indicated that approximately 30% of neuronal perikarya at the C2 level, 52% of neuronal perikarya at the T6 level, and 18% of neuronal perikarya at the L2 level of the cord exhibited taurine-like immunoreactivity. With preembedding diaminobenzidine staining, approximately 20% of the axons examined in laminae I and II were found to be immunoreactive for taurine. Using postembedding immunogold staining in combination with quantitative procedures, the highest densities of gold particles were found in axon terminals containing pleomorphic vesicles and forming symmetrical synapses (36.8 particles/micron2), in a subpopulation of myelinated axons (34.2 particles/micron2), in a subpopulation of neuronal dendrites (32.6 particles/micron2), and in capillary endothelial cells (39.8 particles/micron2). Moderate labeling occurred in astrocytes (20.9 particles/micron2) and neuronal perikarya (18.7 particles/micron2). The localization of taurine to presumptive inhibitory axon terminals provides anatomical support for the hypothesis that taurine may serve an inhibitory neurotransmitter role in the superficial dorsal horn of the spinal cord. On the other hand, its localization to astrocytes and endothelial cells within both the dorsal ventral horns implies that it serves other nonneuronal functions as well. 相似文献