全文获取类型
收费全文 | 6786篇 |
免费 | 244篇 |
国内免费 | 70篇 |
专业分类
耳鼻咽喉 | 1139篇 |
儿科学 | 137篇 |
妇产科学 | 23篇 |
基础医学 | 426篇 |
口腔科学 | 576篇 |
临床医学 | 647篇 |
内科学 | 173篇 |
皮肤病学 | 22篇 |
神经病学 | 489篇 |
特种医学 | 584篇 |
外科学 | 647篇 |
综合类 | 424篇 |
预防医学 | 250篇 |
眼科学 | 35篇 |
药学 | 235篇 |
中国医学 | 80篇 |
肿瘤学 | 1213篇 |
出版年
2023年 | 90篇 |
2022年 | 211篇 |
2021年 | 258篇 |
2020年 | 234篇 |
2019年 | 269篇 |
2018年 | 284篇 |
2017年 | 249篇 |
2016年 | 192篇 |
2015年 | 188篇 |
2014年 | 490篇 |
2013年 | 373篇 |
2012年 | 330篇 |
2011年 | 317篇 |
2010年 | 295篇 |
2009年 | 335篇 |
2008年 | 326篇 |
2007年 | 304篇 |
2006年 | 266篇 |
2005年 | 227篇 |
2004年 | 166篇 |
2003年 | 143篇 |
2002年 | 110篇 |
2001年 | 126篇 |
2000年 | 120篇 |
1999年 | 119篇 |
1998年 | 103篇 |
1997年 | 88篇 |
1996年 | 69篇 |
1995年 | 81篇 |
1994年 | 64篇 |
1993年 | 46篇 |
1992年 | 47篇 |
1991年 | 41篇 |
1990年 | 25篇 |
1989年 | 29篇 |
1988年 | 27篇 |
1987年 | 32篇 |
1986年 | 31篇 |
1985年 | 62篇 |
1984年 | 57篇 |
1983年 | 35篇 |
1982年 | 35篇 |
1981年 | 39篇 |
1980年 | 38篇 |
1979年 | 33篇 |
1978年 | 14篇 |
1977年 | 20篇 |
1976年 | 20篇 |
1975年 | 10篇 |
1973年 | 11篇 |
排序方式: 共有7100条查询结果,搜索用时 15 毫秒
21.
Bernd Niederhagen N. Leipner S. Bergé J.-J. von Lindern T. Appel 《Mund-, Kiefer- und Gesichtschirurgie》2000,4(4):217-221
Problem: There is a lack of clear criteria for the use of MR and CT in the diagnosis of head and neck cancer – some of it
is even contradictory. The results of this study should lead to the establishment of more clear criteria. Patients: 165 patients
suffering from head and neck tumors were subjected to a total of 463 CT and 197 MRI examinations. Results: The CT and MRI
staging corresponded in 67% and 60% of the oropharynx tumors, respectively, with the clinical findings. In the case of oral
cavity tumors, the clinical TNM stages were identical with CT and MRI results in 50% and 43% of cases, respectively. In the
case of lymphatic node staging, the frequency of error was slightly higher using MRI, at 27%, compared with the CT rate of
22%. In the evaluation of cervical lymphatic nodes, CT proved to be more sensitive attaining 78% compared to the MRI rate
of 69%. Conclusion: The results provide clear indications as to the MRI and CT examinations. Primary preoperative screening
and post-therapeutic aftercare should be assessed using CT, as should lymphatic node diagnosis in the neck area. In the case
of special problems such as, for example, the relevant bone and periostium infiltration, MR should be considered as a supplementary
examination at a second stage.
相似文献
22.
颅底富血供肿瘤术前超选择性颈外动脉插管栓塞9例报告 总被引:3,自引:0,他引:3
目的:探讨超选择性颈外动脉插管栓塞术在颅底富血供肿瘤手术治疗中的作用。方法:对9例颅底富血供肿瘤患者术前先作双侧颈内、颈外及椎动脉造影后再行栓塞治疗。结果:9例栓塞后,肿瘤供血网显影消失,术中出血量明显减少,术后病理检查,镜下均见瘤体微血管及血窦内充满大量明胶海绵。结论:超选择性颈外动脉插管造影,在明确肿瘤血供类型后辅以术前栓塞治疗,既可缩小瘤体又能减少术中出血,是肿瘤围手术期处理的重要手段之一。 相似文献
23.
David J. Donahue Robert Alex Sanford Michael S. Muhlbauer William M. Chadduck 《Child's nervous system》1995,11(12):692-697
In the past, the diagnosis of growing skull fracture or diastatic fracture has included a subset of injuries better referred to as cranial burst fracture. Cranial burst fracture, typically associated with severe injury in infants less than 1 year of age, is a closed, widely diastatic skull fracture accompanied by acute cerebral extrusion outside the calvarium. We treated 11 such infants at the LeBonheur Children's Medical Center and 2 at the Children's National Medical Center from January 1986 through December 1994. Infants ranged in age from 1 to 17 months, with an average age of 5.7 months. All presented with marked scalp swelling and a Glasgow Coma Scale score of 10 or less. Twelve had a history consistent with severe injury (motor vehicle accident, 7, abuse 5). The cause of injury in one patient remains unproven. Surgery (reduction of herniated cerebral tissue, repair of large dural laceration, and cranioplasty) was usually performed within 10 days of injury, a time period long enough to assure hemodynamic stability and resolution of acute cerebral swelling, yet sufficiently brief to avoid the chronic changes (scarring, parasitization of scalp vessels by damaged cortex) associated with a growing skull fracture. Prompt repair of cranial burst fracture may prevent ongoing brain injury such as has been neuropathologically demonstrated in patients with growing skull fracture. Magnetic resonance imaging establishes the diagnosis of cranial burst fracture in equivocal cases, rendering unnecessary a waiting period to see if scalp swelling resolves. Our experience, together with information in the neuropathological and neurosurgicla literature, suggests that cranial burst fracture is associated with severe trauma, requires expeditious treatment, and has been underdiagnosed in the past, leading to growing skull fracture, a condition requiring more extensive surgery. 相似文献
24.
石云风 《山西职工医学院学报》1999,(2)
本文从5个方面论述了公关意识及其临床作用。即①塑造形象的意识;②服务公众的意识;③沟通交流的意识;④创新审美的意识;⑤真诚互惠的意识。通过对其作用的论述,旨在引起广大护理工作者对公共关系的重视,从而促进护理学科发展。 相似文献
25.
B. Dahl B. Bergholt G. E. Cold J. Astrup B. Mosdal K. Jensen J. O. Kjærsgaard 《Acta neurochirurgica》1996,138(3):265-273
Summary The purpose of this study was to compare the effect of hyper-ventilation and indomethacin on cerebral circulation, metabolism and pressures in patients with acute severe head injury in order to see if indomethacin may act supplementary to hyperventilation. Fourteen severely head injured patients entered the study. Intracranial pressure (ICP), mean arterial blood pressure (MABP) and cerebral perfusion pressure (CPP) were monitored continuously. Within the first four days after the trauma the CO2 and indomethacin vasoreactivities were studied by measurements of cerebral blood flow (CBF) (Cerebrograph 10a, intravenous133Xe technique) and arterio-venous difference of oxygen (AVdO2). Ischaemia was evaluated from changes in CBF, saturation of oxygen in the jugular bulb (SvjO2), lactate and lactate/oxygen index (LOI). Data are presented as medians and ranges, results are significant unless otherwise indicated.
Before intervention ICP was well controlled (14.8 (9–24) mmHg) and basic CBF level was 39.1 (21.6–75.0) ml/100 g/min). The arterio-venous oxygen differences were generally decreased (AVdO2 = 4.3 (1.8–8.1) ml/100 ml) indicating moderate luxury perfusion. Levels of CMRO2 were decreased (1.54 (0.7–3.2) ml/100 g/min) as well.Duringhyperventilation (APaCO2 = 0.88 (0.62–1.55) kPa) CBF decreased with 11.8 (–33.4–29.7) %/kPa and ICP decreased with 3.8 (0–10) mmHg. AVdO2 increased 34.0 (4.0–139.2) %/kPa, MABP was unchanged, CMRO2 and CPP increased (CPP = 3.9 (–10–20) mmHg). AVD (lactate) and LOI were unchanged. No correlations between CBF responses to hypocapnia and outcomes were observed.An i.v. bolus dose ofindomethacin (30 mg) decreased CBF 14.7 (–16.7–57.4) % and ICP decreased 4.3 (–1–17) mmHg. AVdO2 increased 27.8 (–40.0–66.7)%, MABP (MABP = 4.9 (–2–21) mmHg) and CPP (CPP = 8.7 (3–29) mmHg) increased while CMRO2 was unchanged. No changes in AVd (lactate) and LOI indicating cerebral ischaemia were found.Compared to hyperventilation (changes per 1 kPa, at PaCO2 level = 4.05 kPa) the changes in MABP, CPP and CBF were significantly greater after indomethacin, while the changes in AVdO2, ICP, SvjO2, and LOI were of the same order of magnitude.Nocorrelation between relative reactivities to indomethacin and CO2, evaluated from changes in CBF and AVdO2, or between the decrease in ICP after the two procedures were found. Thus, some patients reacted to indomethacin but not to hyperventilation, and vice versa.These results suggest that indomethacin and hyperventilation might act independently, or in a complementary fashion in the treatment of patients with severe head injury. 相似文献
26.
Seizures and civilian head injuries 总被引:4,自引:3,他引:1
Although several studies have reported on the risk of "early seizures" (seizures occurring within 7 days following a head injury), the reported proportions of patients experiencing these seizures vary from 1.4 to 15%. This wide divergence may be due to problems with methodology such as case selection and definitions of head injury and early seizures. In a series of 702 patients admitted with a head injury to Cook County Hospital (CCH), Chicago, Illinois, 29 (4.1%) had early seizures. This proportion is twice as high as one previously reported in a comparable series. This may reflect an actual difference between the two series or a case selection bias serving to elevate the proportion of patients with early seizures at CCH. 相似文献
27.
Summary Contusions and lacerations of the frontal lobes are very frequent; 43.4% in the whole series of traumatic brain mass lesions. Clinical, ICP, CT scan data and neuropathological findings in patients with such lesions are analysed and correlated. Moreover, the clinical features and the outcome of frontal masses undergoing surgery are also compared with similar lesions located in the temporal lobes.Frontal lesions cannot be differentiated on purely clinical grounds and the factors governing the outcome in both locations are the same. On the whole, surgical indications nowadays seem to be rather rare; only lesions behaving truly as expanding lesions with obvious intracranial hypertension benefiting from surgery.Brain contusion-laceration syndromes in general can no longer be considered separate entities. Neither should they be included in the miscellaneous group of traumatic intracranial mass lesions, since the pathophysiological significance of purely extracerebral effusions is entirely different.Traumatic contusions and lacerations and/or intracerebral haematomas, whether frontal or located elsewhere, should, instead, be considered in the context of head injuries of a different degree of gravity, as having collateral features which, on occasion, may call for surgical management. 相似文献
28.
Embolization with “Ethibloc” of vascular tumors and arteriovenous malformations in the head and neck
Summary Ethibloc has been used almost exclusively until now for embolization of tumors and bleeding vessels in the liver and kidney. Unlike with Gelfoam-particles, there is no recanalization. The resorption occurs so slowly that there is no interference with the necrosis of the embolized tumor. Due to its low viscosity, it passes catheters with thin lumina and fills the capillary bed of the tumor without danger of reaching the venous vessels. In this paper we describe a new technic of percutaneous catheter-embolization with Ethibloc using a coaxial catheter which we believe enhances safety and effectiveness. It has been successfully used in five patients. In the meantime two more patients have been treated successfully.Presented in part at the 17th Annual Meeting of the German Society of Neuroradiology, 9–10 October 1981 in Tübingen, FRG. 相似文献
29.
头颈部坏死性筋膜炎7例临床分析 总被引:4,自引:0,他引:4
目的:探讨头颈部坏死性筋膜炎的病因、临床表现、诊断和治疗,加强对这一罕见疾病的认识。方法:回顾分析1992-2002年10年收治的7例头颈部坏死性筋膜炎的病例资料并复习文献。结果:7例全部行积极的内科保守治疗和外科处理(包括局部切开引流、清创术和气管切开术),其中2例死亡。结论:临床上对该病应有足够的认识,以期早期诊断。及时有效的外科处理是治疗成功的关键。 相似文献
30.
W. Koelfen M. Freund D. Dinter B. Schmidt S. Koenig C. Schultze J. Runde 《European journal of pediatrics》1997,156(3):230-235
The primary issues addressed in this study were: (1) determination of the significance of the classification “good outcome”
utilizing the Glasgow Outcome Scale (GOS) in children at least 1 year after brain injury; (2) detection of residual lesions
of brain parenchyma in these children upon follow up MRI scans; and (3) detection of relationships between neuropsychological
test performance and MRI results. Selection criteria included children 6–15 years of age at the time of testing who received
an initial CT scan at the time of their head injury and who had been injured at least 12 months prior to the follow up test.
Only children who did not demonstrate neurological disability at the time of follow up examination were selected. The children
showed a status of “good outcome” as defined by the GOS. Neurological examination, neuropsychological tests and an MRI were
done. The test results of 59 patients were compared to those of a matched control group. Children, after receiving head injuries,
showed significantly poorer results with respect to cognitive, motor and fine motor skills. Of all MRI-scans 66% revealed
pathological findings. Cortical lesions were detected on MRI in 14% of cases; subcortical injuries were detected in 12% and,
deep white matter lesions in 31%. Furthermore, corpus callosum damage was observed in 26% of cases. Pathological MRI findings
were also observed in children with mild head injuries. All of the children with normal MRI findings showed abilities comparable
to those of children in the control group. Patients with cortical lesions exhibited only motor deficits, whereas motor and
cognitive deficits were seen in patients with deep white matter lesions. Children with multiple lesions demonstrated test
results in all variables 1 to 2 standard deviations below those of the control group.
Conclusions Children suffering a brain injury who 1 year later are classified within the “good outcome” group according to the Glasgow
Outcome Scale often have significant morphological and functional brain deficits.
Received: 6 January 1996 / Accepted: 10 August 1996 相似文献