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41.
我们研究了不同记忆负荷条件下,ERP-P_(300)变化的规律性和特点及ERP-P_(300)与脑力负荷难度之间的关系。在三种脑力作业时,要求受试者记忆2、4、6位随机数字。结果表明,1、随着记忆数字增加,P_(300)波幅相应增大,三种记忆作业P_(300)波幅之间均有显著性差异。2、记忆错误率和记忆难度主观评价值,亦随着记忆数字增加而增大,且在三种记忆作业之间均有显著性差异。3、P_(300)波幅和记忆难度主观评价值之间相关分析表明呈正相关(P<0.01)。我们建议,P_(300)波幅测量可以作为评价脑力负荷的一项客观指标。 相似文献
42.
ADEL ISSA SOUSSOU MOHAMED GAMAL HELMY RAMEZ RAOUF GUINDY ENRICO MARIA GRECO 《Pacing and clinical electrophysiology : PACE》1992,15(11):1804-1808
The pocing rate response of a new acceleration driven pulse generator (SWING 100, SORIN BIOMEDICA) was compared with simultaneous normal sinus rhythm (NSR) during two different treadmill exercises. This pacemaker has a gravitational acceleration sensor able to discriminate between physical activities and vibrations. Six healthy volunteers (three male, three female; aged 21.7 ± 4,3 years), with the pacemaker strapped to their right infraclavicular area, performed each test three times with different rise response curve (RRC) each time: fast, normal, and slow. The fall response curve used was the same as the rising one during each test. Pacing rates were recorded using the VEGA analyzer (SORIN BIOMEDICA) and compared with simultaneous NSR recorded by a 7-channel ECG recorder (MINGOGRAF 7, SIEMENS), During all tests immediate (within seconds) rapid increase in pacemaker rate was seen up to about 60 seconds, then a slower increase followed thereafter. The mean correlation between pacing rates and NSR during the Bruce tests were 0.7941 ± 0.10, 0.8562 ± 0.14, and 0.8292 ± 0.07; during the discontinous tests 0.7292 ± 0.16, 0.7233 ± 0.10, and 0.7480 ± 0.11 for fast, normal, and slow RRC, respectively. Each 30 seconds, nonsignificant differences were present between pacing rate and NSR during all the discontinuous tests; similar responses were observed only during the first two stages of Bruce tests after which NSR was significantly higher than pacemaker rates. The speed of rise to upper rate was the main difference between the different programs (fast, normal, and slow). The discontinuous tests showed that the pacemaker responds more to speed than to grade. In conclusion, the Swing pacemaker is easy to use and program, fast, reliable, and is able to mimic the normal sinus behavior especially during discontinuous activities. 相似文献
43.
Atul K. Sharma Moira S. Mills Vijay L. Grey Keith N. Drummond 《Pediatric nephrology (Berlin, Germany)》1997,11(6):711-713
Accurate, timed urine collections for the measurement of glomerular filtration rate (GFR) may be impractical in infants or
in patients with urological abnormalities. GFR may be measured without urine collection using a constant subcutaneous infusion
of iothalamate. We compare the infusion clearance with conventional renal clearance in 14 children and young adults. The mean
clearance ratio (infusion clearance/renal clearance ± 1 SD) was 0.99±0.1 and the mean discrepancy between the two methods
was 8.5%±4.7%. The 95% limits of agreement for the ratio of the two methods are 0.83–1.23. These data indicate that subcutaneous
infusion of iothalamate is a practical method for measuring GFR in children without a urine collection.
Received March 18, 1996; received in revised form February 12, 1997; accepted March 26, 1997 相似文献
44.
1992年12月作者从一位EHF患者的早产儿脐带血中分离出EHFV,证实EHFV沿母、婴垂直途径传播的可能性。 相似文献
45.
目的:了解近年来泌尿系细菌感染致病菌及耐药性,为合理应用抗生素,提供临床根据。方法:对泌尿系感染患者298株病原菌进行药物敏感试验。结果:大肠埃希菌仍是引发泌尿系感染的主要病原菌,占53%,其次是葡萄球菌属,占19.40%,肠杆菌属占10.06%,肠球菌属占4.70%等,各类菌属耐药情况。结论:临床医师必须关注本地病原菌分布及耐药情况,合理应用抗生素,减少耐药性播散。 相似文献
46.
气功对冠心病人CM_5ST段/心率斜率的影响 总被引:1,自引:0,他引:1
37名冠心病患者随机分为气功治疗组(22人)和对照组(15人)。气功治疗组接受12周动功治疗,对照组接受安慰剂治疗,治疗前后均测定CM_5 ST段/心率斜率。结果发现动功治疗组CM_5 ST段/心率斜率减少,而对照组不变或增大,两组有显著性差异,ST段下移及常规分级运动试验其它指标在两组间无显著差异。表明CM_5ST段/心率斜率是一个敏感的心肌缺血指标。 相似文献
47.
J. Åkeson M.D. F. Nilsson E. Ryding K. Messeter 《Acta anaesthesiologica Scandinavica》1992,36(5):419-426
We present a physiologically stable porcine model designed for sequential assessments of pharmacological effects on mean hemispheric cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO2) at sustained normocapnia. The dynamic influence of continuously administered fentanyl (0.040 mg.kg-1.h-1 i.v.), nitrous oxide (70%) and pancuronium (0.30 mg.kg-1.h-1 i.v.) on these variables was studied in eight normoventilated pigs. CBF was reliably assessable at 10-min intervals by clearance of intra-arterially injected 133Xe, monitored by an extracranial scintillation detector. CMRO2 was calculated from CBF and the simultaneously measured cerebral arteriovenous difference in blood oxygen content. The intracerebral distribution of a contrast medium injected into the external and internal carotid arteries was studied by angiography, and the cerebral venous outflow was investigated by measurements of the distribution of an intra-arterially administered non-diffusible tracer, [99mTc]pertechnetate, to the internal and external jugular veins. After a 3-h equilibration period, CBF and CMRO2 were determined on six occasions over a study period lasting 1 h 40 min. The mean ranges of these variables were 56-60 and 1.9-2.0 ml.100 g-1.min-1, respectively. We conclude that the model enables repeated assessments of CBF and CMRO2 under stable physiological background conditions and thus valid cerebral pharmacodynamic investigations of drugs given for anaesthesia. 相似文献
48.
A recent large increase in Caesarean section (CS) in Italy was the initial stimulus for a study to identify risk factors for CS and, if possible, to suggest strategies to counteract the rise. The study was conducted in three hospitals where a wide range of individual variables was collected from the clinical records and from personal interviews. Crude CS rates and odds ratios were evaluated for each single variable while logistic regression has been used to investigate possible confounding factors. The study involved 1316 consecutive deliveries. Crude CS rates were 29.4%, 15.7% and 16.1%. Variables identified as high risk factors were pre-eclampsia, previous CS, breech and other non-vertex presentations. Antenatal care under an obstetrician working in the same hospital, a low number of antenatal consultations, previous miscarriages, offer (by obstetrician) and request (by women) for CS showed significantly high odds ratios (ORs). Previous live births was strongly negatively associated with CS. No relationship between type of delivery and social status was observed while a physician factor was detected in all three hospitals where rates for different physicians ranged from 0% to 52.8%. Apart from the main medical indications for Caesarean section (previous CS, breech presentation), the results seem to indicate that individual practice style may be an important determinant of the wide variation in the rates of Caesarean delivery. While this may have been suspected before this study, these results are the first hard data to indicate that, in Italy, CS is widely performed for non-medical reasons. 相似文献
49.
农村健康保险的精算体系 总被引:5,自引:0,他引:5
本文提出了我国农村健康保险的精算体系和测算保险费、管理费、储备金、预防保健费、保险因子、增加系数、医药费及其补偿比的实用方法。 相似文献
50.
Benoit J. M. Pirotte Alphonse Lubansu Michael Bruneau Chakir Loqa Nathalie Van Cutsem Jacques Brotchi 《Child's nervous system》2007,23(11):1251-1261
Objective The objective of this study was to evaluate whether the rigid application of a sterile protocol for shunt placement was applicable
on a routine basis and allowed the reduction of shunt infections (SI) in children.
Materials and methods Since 2001, a rigid sterile protocol for shunt placement in children using neither antibiotic-impregnated catheters nor laminar
airflow was prospectively applied at Erasme Hospital, Brussels, Belgium. For assessing the protocol efficacy before continuation,
we preliminarily analyzed the results of the first 100 operated children (43 females, 57 males, 49 aged <12 months; 115 consecutive
shunt placement/revision procedures). All procedures were performed by the same senior surgeon, one assistant, one circulating
nurse, one anesthesiologist. The sterile protocol was rigidly imposed to these four staff members: uniformed surgical technique;
limited implant and skin edge manipulation; minimized human circulation in the room; scheduling surgery as first morning operation;
avoiding postoperative cerebrospinal fluid (CSF) leak; double gloving; procedures of less than 30-min duration; systemic antibiotics
prophylaxis. We analyzed separately: (1) children carrying an increased risk of SI (n = 38) due to preoperative external ventricular drainage, CSF leak, meningitis, glucocorticoids, chemotherapy; (2) children
aged <12 months; (3) procedures for shunt revision.
Results Errors in protocol application were recorded in 71/115 procedures. They were mainly done by non-surgical staff, decreased
with time and were medically justified in some young children. Surprisingly, no SI occurred (follow-up, 4 to 70 months). One
child developed an appendicitis with peritonitis (Streptococcus faecalis) after 6 months. No SI was found. After peritonitis was cured, shunt reinsertion was uneventful.
Conclusion These preliminary results suggest that a uniform and drastic sterile surgical technique for shunt placement: (1) can be rigidly
applied on a routine basis; (2) can lower the early SI rate below 1%; (3) might have a stronger impact to reduce SI than using
antibiotic-impregnated catheters and optimizing the operative environment such as using laminar airflow and reducing the non-surgical
staff. This last issue will be evaluated further in the present ongoing protocol. 相似文献