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81.
82.
国人C型肝性脑病发病诱因分析 总被引:1,自引:0,他引:1
目的了解国人C型肝性脑病发病诱因及相关因素。方法对国内已经发表的11个研究样本(患者总样本量1131例)进行综合分析。结果在9类纳入统计分析的诱因中:消化道出血占43.8%、各种感染占33.9%、电解质紊乱占29.1%、医源性因素占28.2%、饮食不节占14.2%、肾功能衰竭占13.0%,分居前6位,另外腹泻占2.4%,便秘占1.8%,原因未明/无占2.7%。其中医源性因素按照发生频率依次为:大量利尿和/或放腹水占14.5%、手术/创伤占6.0%,药物占4.5%,输血/输复合氨基酸占3.2%。结论警惕肝性脑病多种诱因的存在,尤其不能忽视医源性因素。按照发病概率积极寻找并消除诱因,对于改善顸后尤为重要。 相似文献
83.
CT血管成像对肝细胞癌合并肝动脉-门静脉分流的诊断价值 总被引:4,自引:0,他引:4
目的探讨CT血管成像(CTA)对肝细胞癌(HCC)合并肝动脉-门静脉分流(APS)的诊断价值。方法127例HCC患者分别接受肝脏多层螺旋CT动态增强扫描和DSA检查,间隔时间3-15d。所有患者进行CTA检查,并以DSA为标准,对照分析CT动态增强扫描基础上进行CTA成像对APS的诊断价值。结果DSA证实52例(40.94%)HCC患者合并APS,中央型33例,周围型19例。CT横断面与横断面基础上结合CTA诊断APS的敏感度均为94.23%(49/52),特异度分别为84.00%(63/75)和97.33%(73/75),正确率分别为88.19%(112/127)和96.06%(122/127),阳性预测值分别为80.33%(49/61)和96.08%(49/51),阴性预测值分别为95.45%(63/66)和96.05%(73/76)。CTA排除了横断面CT对4例中央型APS和6例周围型APS的假阳性诊断。与DSA比较,多层螺旋CT对APS的分型符合率达88.46%(46/52),其中,中央型90.91%(30/33),周围型84.21%(16/19)。CTA还直观地显示23例重度分流中央型APS的供血动脉,其中19例为肝固有动脉分支,4例为胃十二指肠动脉分支。结论在多层螺旋CT动态增强扫描基础上进行CTA成像,能有效提高APS诊断的特异度和正确率。 相似文献
84.
Background: Retinal pigment epithelium (RPE)lesions are predictive congenital phenotypic markersfor familial adenomatous polyposis (FAP). Thisprospective screening study aims at assessing theincidence and significance of these lesions in FAPpatients and their family members.Methods: Sixty-two members from three familiesincluding five patients with the diagnosis of FAP havebeen ophthalmologically surveyed. All RPE lesions weredocumented with fundus photography and fluoresceinangiography was performed in 13 subjects.Sigmoidoscopy and/or radiological examination wereperformed annually in 9 family members with typicalRPE lesions during 4 years to allow early diagnosis ofFAP.Results: Typical RPE lesions were present infive FAP patients and 15 family members.Telangiectatic dilatations in the retinal peripherywith small dot-like hemorrhages were detected in 6subjects from 3 families These lesions wereparticularly evident on fluorescein angiography.Annual colon analysis showed polyps in 3 out of 9subjects who were positive for RPE lesions.Conclusion: RPE lesions are valuable as aclinical marker in predicting FAP. The co-existingperipheral vascular alterations which have not beenreported before, are probably related to FAP. 相似文献
85.
HATIM A. OMAR M.D. LARRY A. RHODES M.D. ROLANDO RAMIREZ JELICA ARSICH M.D. STANLEY EINZIG M.D. Ph .D. 《Journal of cardiovascular electrophysiology》1996,7(12):1197-1203
Antiarrhythmic and Placental Vessels. Introduction : Antiarrhythmic medications are commonly used during pregnancy for treatment of maternal or fetal arrhythmias, but little is known about their effect on human placental vascular tone and, consequently, placental blood flow. The objective of this study was to evaluate the tone responses caused by antiarrhythmic medications in human placental vessels from normal term pregnancies in vitro.
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO2 35 to 38 torr) were exposed to cumulative doses of quinidine, procainamide, lidocaine, flecainide, propranolol, amiodarone, verapamil, digoxin, and adenosine after submaximal contraction with 5-hydroxytryptamine. The study was conducted both in the presence and absence of endothelium. The addition of the tested medications caused a significant, dose-dependent relaxation of human placental arteries and veins except for adenosine, which induced a sustained, dose-dependent contraction of human placental vessels regardless of the presence or absence of tone. Removal of the endothelium did not alter these responses.
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor. 相似文献
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor. 相似文献
86.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献
87.
The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass.Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor.Using this approach, we performed four aortobifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region. 相似文献
88.
目的:观察偏瘫患者早期床上训练的效果。方法:对58例脑血管意外致偏瘫患者随机分成2组:观察组30例,护理中指导早期床上体操训练;对照组28例,按常规护理。以上、下肢肌力和日常生活活动能力(ADL)为评价指标,于训练开始时、训练4周、训练8周各评价1次。结果:观察组训练4周、8周时患侧上肢肌力以及ADL水平明显增加,与对照组比较有显著差异(P<001)。患侧下肢肌力训练4周及8周时均增加,与对照组比较,4周时无明显差异(P>005),8周时有显著性差异(P<001)。结论:对早期偏瘫患者实施床上功能训练,不仅可以提高患者的生命质量,而且可以减少、甚至解除患者及家属的经济和精神负担。 相似文献
89.
J. Åberg B. Abrahamsson M. Grind G. Nyberg B. Olofsson 《European journal of clinical pharmacology》1997,52(6):471-477
Objective: The primary aim of this study was to investigate whether bioequivalence is achieved for a new fixed combination of extended-release
(ER) felodipine and controlled-release (CR/ZOK) metoprolol␣compared with the free combination of felodipine ER metoprolol
CR/ZOK. The second aim was to study whether there was an interaction in pharmacokinetics and pharmacodynamics between felodipine
and metoprolol when administered as ER formulation.
Methods: Two four-way cross-over studies were performed in 36 young subjects and 24 elderly subjects with frequent measurement of
drug plasma concentrations, blood pressures and heart rate. The pharmacokinetic analysis included enantioselective analysis
in six subjects.
Results: Bioequivalence between the fixed combination and the free combination was observed for the two drugs (mean difference 27%)
except for a minor deviation regarding Cmax of metoprolol in the elderly. No significant interaction was shown except for a small increase (6%) of metoprolol AUC in
the younger subjects. Mean plasma S-/R-enantiomer ratios were almost identical for the different treatments. Blood pressure and heart rate was significantly reduced
for the fixed combination compared with felodipine ER in the younger and the elderly subjects. No significant difference regarding
pharmacodynamics was detected between the fixed combination and the corresponding free combination.
Conclusion: The fixed combination consistently provides fairly constant and effective felodipine and metoprolol concentrations after
once-daily administration of one tablet. It is clinically interchangeable with the free combination of metoprolol CR/ZOK tablets
and felodipine ER tablets. Finally, felodipine and metoprolol do not interact on a pharmacokinetic level when administered
as the fixed combination.
Received: 29 October 1996 / Accepted in revised form: 21 March 1997 相似文献
90.
Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery. 相似文献