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31.
Ontogenesis of the secretory immune system and innate defence factors in human parotid glands 下载免费PDF全文
Immunoglobulin-producing cells and epithelial expression of secretory component (SC), amylase, lysozyme (Ly) and lactoferrin (Lf) were studied by immunohistochemistry to obtain information about the development of mucosal immunity. Tissue specimens were obtained from 20 fetal and 40 postnatal parotid glands. (1) Fetal specimens. Occasional IgM- and IgA- but no IgD-, IgG- or IgE- producing cells were seen (ratios, IgM:IgA:IgD:IgG:IgE approximately 4:1:0:0:0). The IgAl subclass dominated (median 90%, range 50-95%) and these cells were mostly J-chain-positive (median 97%, range 94-98%). Only few IgA2-producing cells were seen (median 10%, range 5-50%) and they were also mostly J-chain-positive (median 99%, range 98-100%). Amylase, Ly and Lf were most prominent in early fetal life, while only small amounts of SC were present. (2) Postnatal specimens. Secretory component increased markedly along with a growing number of IgA- and IgD-producing cells (IgA:IgM:IgD:IgG:IgE approximately 4:2:1:1:0). The IgAl subclass remained predominant (median 65%, range 50-90%) although the proportion of IgA2-positive cells tended to be raised (median 35%, range 10-50%). Most IgAl (median 97%, range 67-100%) and IgA2 (median 94%, range 75-100%) cells were J-chain-positive. These features probably reflected local activation of the immune system in response to environmental factors. The amount of amylase, Ly and Lf decreased shortly after delivery, perhaps because the cellular stores were emptied by postnatal increase in secretory activity. 相似文献
32.
The purpose of the present study was to examine comprehensively the kinetics of oxygen uptake (
) during treadmill running across the moderate, heavy and severe exercise intensity domains. Nine subjects [mean (SD age,
27 (7) years; mass, 69.8 (9.0) kg; maximum
,
, 4,137 (697) ml·min–1] performed a series of "square-wave" rest-to-exercise transitions of 6 min duration at running speeds equivalent to 80% and
100% of the
at lactate threshold (LT; moderate exercise); and at 20%, 40%, 60%, 80% and 100% of the difference between the
at LT and
(Δ, heavy and severe exercise). Critical velocity (CV) was also determined using four maximal treadmill runs designed to result
in exhaustion in 2–15 min. The
response was modelled using non-linear regression techniques. As expected, the amplitude of the
primary component increased with exercise intensity [from 1,868 (136) ml·min–1 at 80% LT to 3,296 (218) ml·min–1 at 100% Δ, P<0.05]. However, there was a non-significant trend for the "gain" of the primary component to decrease as exercise intensity
increased [181 (7) ml·kg–1·km–1 at 80% LT to 160 (6) ml·kg–1·km–1 at 100% Δ]. The time constant of the primary component was not different between supra-LT running speeds (mean value range
= 17.9–19.1 s), but was significantly shorter during the 80% LT trial [12.7 (1.4) s, P<0.05]. The
slow component increased with exercise intensity from 139 (39) ml·min–1 at 20% Δ to 487 (57) ml·min–1 at 80% Δ (P<0.05), but decreased to 317 (84) ml·min–1 during the 100% Δ trial (P<0.05). During both the 80% Δ and 100% Δ trials, the
at the end of exercise reached
[4,152 (242) ml·min–1 and 4,154 (114) ml·min–1, respectively]. Our results suggest that the "gain" of the primary component is not constant as exercise intensity increases
across the moderate, heavy and severe domains of treadmill running. These intensity-dependent changes in the amplitudes and
kinetics of the
response profiles may be associated with the changing patterns of muscle fibre recruitment that occur as exercise intensity
increases.
Electronic Publication 相似文献
33.
34.
Morphologic evaluation of the liver in hereditary angioedema patients on long-term treatment with androgen derivatives 总被引:1,自引:0,他引:1
M Cicardi L Bergamaschini A Tucci A Agostoni G Tornaghi G Coggi R Colombi G Viale 《The Journal of allergy and clinical immunology》1983,72(3):294-298
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses. 相似文献
35.
The aim of the study was to examine to what extent prior high- or low-intensity cycling, yielding the same amount of external
work, influenced the oxygen uptake (V˙O2) slow component of subsequent high-intensity cycling. The 12 subjects cycled in two protocols consisting of an initial 3 min
period of unloaded cycling followed by two periods of constant-load exercise separated by 3 min of rest and 3 min of unloaded
cycling. In protocol 1 both periods of exercise consisted of 6 min cycling at a work rate corresponding to 90% peak oxygen
uptake (V˙O2peak). Protocol 2 differed from protocol 1 in that the first period of exercise consisted of a mean of 12.1 (SD 0.8) min cycling
at a work rate corresponding to 50% V˙O2peak. The difference between the 3rd min V˙O2 and the end V˙O2 (ΔV˙O2(6−3)) was used as an index of the V˙O2 slow component. Prior high-intensity exercise significantly reduced ΔV˙O2(6−3). The ΔV˙O2(6−3) was also reduced by prior low-intensity exercise despite an unchanged plasma lactate concentration at the start of the second
period of exercise. The reduction was more pronounced after prior high- than after prior low-intensity exercise (59% and 28%,
respectively). The results of this study show that prior exercise of high as well as low intensity reduces the V˙O2 slow component and indicate that a metabolic acidosis is not a necessary condition to elicit a reduction in ΔV˙O2(6−3).
Accepted: 8 July 2000 相似文献
36.
阿尔茨海默病(AD)是最常见的痴呆形式,目前缺少疾病修饰性的治疗药物。中医理论认为肾精亏虚是AD发生发展的内在机制,补肾益精是中医治疗AD的基本原则,贯穿AD治疗的始终。补肾益智方是治疗AD的临床经验方。补肾益智方治疗AD已有大量文献报道,但补肾益智方缺乏临床应用安全性评价,同时其基础研究薄弱,有效成分不明、多靶点作用机制不清。为阐明补肾益智方多成分、多靶点、多途径治疗AD的作用机制,该文综述了补肾益智方治疗AD的研究进展。进一步收集了16个基于高效液相色谱指纹图谱的补肾益智方主要化学成分,并对其成药性与安全性进行评价。利用基于AD重要病理生理学过程的网络药理学与文献综述相结合的方法,深入分析了补肾益智方靶向胆碱能系统、AD神经病理学特征的有效成分及可能机制。该研究为AD对症治疗、疾病修饰性治疗的药物研发提供了一系列有潜力的先导化合物,并为深入拓展补肾益智方的临床应用提供了理论依据。 相似文献
37.
38.
目的 探讨新发结直肠癌患者的膳食模式与发病的关系,为结直肠癌的发生提供科学的干预方向。方法 以2018—2019年辽宁省某肿瘤医院就诊并经病理学确诊的新发结直肠癌患者和同期在该医院体检中心参加健康体检者为研究对象,新发结直肠癌患者为病例组,按同性别、同年龄1∶1选取健康体检者作为对照组,采用主成分分析法对调查对象的膳食模式进行分析,利用Logistic回归模型分析不同膳食模式对结直肠癌发病风险的影响。结果 本研究共对新发结直肠癌患者232例、健康体检者232人进行调查,2组人群在性别、年龄、文化程度、家庭人均月收入和体力劳动强度分布差异均无统计学意义(均P>0.05)。多因素Logistic回归分析结果显示坚果薯类膳食模式(OR=0.482)、水产奶类膳食模式(OR=0.666)和果蔬素食膳食模式(OR=0.800)是结直肠癌发生的保护性因素,西式膳食模式(OR=1.441)、辛辣熏制膳食模式(OR=1.195)、肉类膳食模式(OR=1.397)和高脂肪膳食模式(OR=1.349)为结直肠癌发病的危险因素。结论 坚果薯类、水产奶类和果蔬素食是结直肠癌发生的保护性因素。西式、辛辣熏制、肉类和高脂肪膳食为结直肠癌发病的危险因素,在结直肠癌的防病宣传健康教育中应该加强饮食健康宣传,提高防病意识,有效降低发病率。 相似文献
39.
目的基于主成分分析(PCA)-决策树模型分析脑卒中肺部感染的危险因素及血清免疫炎性因子的预测价值。方法回顾性分析2014年12月-2019年12月江西省上饶市人民医院确诊的176例脑卒中患者,根据是否发生肺部感染,分为感染组40例和未感染组136例。记录患者临床特征,检测血白细胞(WBC)计数、血清C-反应蛋白(CRP)、降钙素原(PCT)和可溶性白细胞介素-2受体(SIL-2R)水平。采用Logistic回归和卡方自动交叉检验(CHAID)模型分析影响脑卒中后肺部感染的危险因素;受试者工作特征曲线(ROC)分析血WBC、CRP、PCT、SIL-2R预测肺部感染的价值。结果脑卒中肺部感染与患者年龄、卒中类型、是否合并糖尿病、吸烟史、吞咽困难、意识障碍、侵入性操作有关(P<0.05);感染组患者血WBC、CRP、PCT和SIL-2R水平高于未感染组(P<0.05);糖尿病、侵入性操作、CRP和PCT均为影响脑卒中患者肺部感染的独立危险因素(P<0.05);PCA-ROC分析显示,血WBC、CRP、PCT、SIL-2R和联合预测主成分1(PC1)的曲线下面积(AUC)分别为0.670、0.816、0.854、0.686、0.918;PCA-卡方自动交互检测(CHAID)模型分析显示,WBC、CRP、PCT、SIL-2R和PC1预测肺部感染的准确率为77.33%、84.72%、86.90%、79.02%和89.24%。结论血清PCT水平可用于预测脑卒中患者肺部感染的发生,临床可重点关注合并糖尿病、意识障碍和侵入性操作的患者。 相似文献
40.
Victor R. Carlson Iain S. Elliott Graham J. DeKeyser Christopher E. Pelt Lucas A. Anderson Jeremy M. Gililland 《The Journal of arthroplasty》2021,36(5):1799-1803
BackgroundDistortion is an intrinsic phenomenon associated with image-intensified fluoroscopy that is both poorly understood and infrequently appreciated by orthopedic surgeons. Little information exists regarding its potential influence on intraoperative parameters during orthopedic surgery, let alone during direct anterior (DA) total hip arthroplasty (THA). The purpose of this study was to quantify the amount of potential error caused by fluoroscopic distortion during DA THA.MethodsIntra-operative fluoroscopic pelvic images from 74 DA THAs were reviewed by two independent readers. All images were obtained using the same fluoroscopic C-arm unit with a radiopaque grid attached to the image intensifier. The vertical distortion from a straight central horizontal line at the peripheries of images were measured and summed to yield the combined vertical distortion similar to how a surgeon calculates a side to side comparison of limb lengths. Simple linear regression was used to evaluate associations between total distortion and patient demographics, operating theaters, and various operative parameters.ResultsThe average combined distortion was 10.0mm (range 2.0-20.0mm). There was a significant difference in the average distortion observed in different theaters (P < .001). There was no association between distortion and patient demographics or fluoroscopic time (all, P > .05).ConclusionFluoroscopic distortion is unpredictable and can cause a substantial amount of error when comparing limb lengths during DA THA. This is a critical finding as this amount of inaccuracy could lead to unintended implant positioning and limb-length discrepancies if unaccounted for. 相似文献