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91.
Vasomotion in rat diaphragm microcirculation at rest and during stepwise arterial pressure reduction
C. W. CHEN C. H. LEE T. R. HSIUE H. Y. CHANG 《Acta physiologica (Oxford, England)》1997,161(3):281-288
The effect of haemorrhagic hypotension on the incidence, frequency and relative amplitude of vasomotion in rat diaphragm microcirculation was assessed by laser Doppler flowmetry (LDF). Graded bleeding to four hypotension levels (80, 60, 40 and 30% of the control state) were performed in 24 Sprague–Dawley rats. The incidence of vasomotion was 83% in the control state, 96% at the 80% level, 100% at the 60% level, 96% at the 40% level, and 46% at the 30% level. The median fundamental frequency of vasomotion determined manually during the control state and at the hypotension levels (in descending order) was 4.11 (range, 3.29–5.58) cycles min?1 (cpm), 4.48 (3.21–5.92) cpm, 4.20 (3.5–5.56) cpm, 4.01 (3.33–5.36) cpm, 3.71 (3.25–4.49) cpm (P < 0.01 from the fundamental frequency at 80 and 60% hypotension levels). The median relative amplitudes determined manually during the control state and descending hypotension levels were 44.5% (range, 24.9–135.9%), 69.4% (26.6–147.2%), 84.0% (40.3–177.1%) (P < 0.01 from resting and last stage of bleeding), 90.40% (26.2–189.6%) (P < 0.01 from resting and last stage of bleeding), 69.2% (35.6–93.2%). We concluded first that during the resting condition, vasomotion was frequently present in diaphragm microcirculation, which is distinct from other vascular beds of skeletal muscles. Second, the relative amplitude of vasomotion during haemorrhagic hypotension plotted against decreasing blood pressure exhibited a reverse U-shaped curve with a maximum at 40–60% of the control blood pressure, while the frequency of vasomotion remained relatively constant until the last stage of haemorrhage and centred around 3–5 cpm. 相似文献
92.
O. Zaha T. Hirata F. Kinjo A. Saito H. Fukuhara 《Journal of infection and chemotherapy》2002,8(1):94-98
We assessed the efficacy and adverse effects of ivermectin for the treatment of chronic strongyloidiasis. Fifty patients
were treated with a single dose of ivermectin at approximately 200 μg/kg, and the dose was repeated 2 weeks later. The eradication
rate was 96% (48 of 50 patients) at 2 weeks after the first dose and 98% at 2 weeks after the second dose (49 of 50 patients).
In the latter cases, no recurrence was noted at the end of the 4-month post-treatment follow-up period. The gastrointestinal
symptoms observed most frequently before the treatment were borborygmus, constipation, and diarrhea. These symptoms improved
in the majority of patients after the treatment. Side effects, including nausea and vomiting, occurred in 1 patient (2%),
but these were mild and transient. Although abnormal values in laboratory tests were observed in 4 patients (8%), they were
mild, and no particular clinical care was required. Thus, ivermectin showed an excellent antihelminthic effect, with little
toxicity. Our results indicate that a regimen of two single doses of 200 μg/kg ivermectin, given 2 weeks apart, is clinically
suitable for the treatment of chronic strongyloidiasis.
Received: April 25, 2001 / Accepted: November 16, 2001 相似文献
93.
We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
94.
目的 探讨急性心肌梗死(AMI)溶栓治疗后无创法评价心肌再灌注的可行性。方法选择AMI溶栓治疗后行冠状动脉造影的患者,溶栓后90min血浆肌红蛋白(Mb)浓度与溶栓前血浆Mb浓度比值≥2.4或心电图ST段回落≥50%定义为成功再灌注(阳性)。上述两项指标均阳性为完全再灌注,仅一项阳性为部分再灌注,两项均阴性为无再灌注。再根据冠状动脉造影结果将患者分为完全再灌注(TIMI3级)、部分再灌注(TIMI2级)、无再灌注(TIMI0~1级)。对无创法和介入法进行一致性检验。共入选45例患者。结果无创法和介入法评价心肌再灌注经一致性检验,符合率为84.4%,Kappa=0.75(P〈0.01)。结论.心电图ST段回落和血浆Mb浓度变化两项指标合用可提高评价心肌再灌注准确性,和介入法有很高的符合率,简便易行,且结果可靠。 相似文献
95.
[目的]比较2,4-二氯苯胺重氮法(DCA)和钒酸盐氧化法检测血清结合胆红素的结果。[方法]根据NCCLS(EP6-P)评价方案,评估两种方法的相关性和偏倚。[结果]两种方法的检测结果相关性良好(r=0.9985),Ⅰ、Ⅱ、Ⅲ组检测结果无差异,Ⅳ组结果有差异。[结论]应建立与方法学相对应的血清结合胆红素参考值范围。 相似文献
96.
4种头孢菌素的抗生素后效应影响因素 总被引:4,自引:0,他引:4
目的:研究头孢呋辛(CXM)、头孢噻肟(CTX)、头孢哌酮(CPZ)、头孢地嗪(CDZM)的抗生素后效应及药物浓度、接触时间、菌种等因素的影响。方法:采用AVANTAGE全勇自动微生物分析仪、用光密度法测定4种抗生素不同浓度对2种共12株临床常见致病菌不同反应时间的体外抗生素后效应(PAE)。结果:4种头孢菌素类药物对革兰阳性球菌有较明显的PAE,对革兰阴性杆菌PAE较小甚至没有或为负值;药物浓度 相似文献
97.
To provide better transient performance in controlling robots, a mixed minimum time and quadratic performance index is used. For known and uncertain revolute robot manipulators a conventional optimal control and a robust guaranteed cost control are proposed respectively. Asymptotic stability is also discussed based on the Lyapunov direct method. The proposed robust control is continuous and requires no knowledge of the uncertain system except for bounding functions. 相似文献
98.
X. Liu R. L. Phillips S. M. Resnick V. L. Villemagne D. F. Wong J. M. Stapleton E. D. London 《Acta neurologica Scandinavica》1995,92(1):83-90
Previous studies of cerebral structure in substance abusers yielded controversial results, largely due to issues of subject selection and/or limitations of experimental techniques. The purpose of the present study was to assess whether the ventricle-to-brain ratio (VBR), determined volumetrically by magnetic resonance imaging (MRI), differed in polysubstance abusers (n = 10), as compared with age-matched controls (n = 10). Subjects were male volunteers 21–39 years of age. The values of VBR in the polydrug abuse group were not larger than those in control group, nor was there any tendency toward relative ventriculomegaly in the substance abusers. Therefore, the present findings provide no evidence that polysubstance abuse produces abnormalities of gross brain structure in relatively young and physically healthy men. 相似文献
99.
作者自行设计一种问卷对某企业职工进行社会心理调查。问卷由 A、B两表构成。A 表列出42个问题,包含可能影响该企业职工社会心理的三大类11项因素,要求从该企业中随机抽取的被调查者针对问题回答“是”或“否”。其后附开放式问题一个,被调查者可自由作答,以补封闭式提问的不足。B 表按心理投射机制设计,以解除被调查者的疑虑。测试结果表明,此问卷的信度和效度令人满意。 相似文献
100.
John E. Burnes David C. Kaelber Bruno Taccardi Robert L. Lux Philip R. Ershler Yoram Rudy 《Annals of biomedical engineering》1998,26(1):37-47
Mapping of bioelectric potentials over a given surface (e.g., the torso surface, the scalp) often requires interpolation of potentials into regions of missing data. Existing interpolation methods introduce significant errors when interpolating into large regions of high potential gradients, due mostly to their incompatibility with the properties of the three-dimensional (3D) potential field. In this paper, an interpolation method, inverse-forward (IF) interpolation, was developed to be consistent with Laplace's equation that governs the 3D field in the volume conductor bounded by the mapped surface. This method is evaluated in an experimental heart–torso preparation in the context of electrocardiographic body surface potential mapping. Results demonstrate that IF interpolation is able to recreate major potential features such as a potential minimum and high potential gradients within a large region of missing data. Other commonly used interpolation methods failed to reconstruct major potential features or preserve high potential gradients. An example of IF interpolation with patient data is provided to illustrate its applicability in the actual clinical setting. Application of IF interpolation in the context of noninvasive reconstruction of epicardial potentials (the inverse problem) is also examined. © 1998 Biomedical Engineering Society.
PAC98: 8710+e, 0260Ed 相似文献