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21.
目的探索以虚拟现实技术为基础的枢椎椎弓根螺钉置人方法。方法选取8具成人颅一颈椎标本,采用改良四柱式定位框架固定于枕颈,使颅-颈-肩形成统一刚体,保持空间位置恒定,CT薄层扫描获取枢椎三维定位信息,采用Aero—Tech立体定向手术规划系统三维建模,设计安全、可视化、个体化的虚拟置钉路径,反复虚拟演示验证钉道安全后,导向弓把持下置人导向钢针,复查CT评价置钉的准确性。结果16个枢椎椎弓根置钉过程中,方向出现偏差(横突孔突破)1个,失败率为6.25%。结论目标椎弓根的容积三维重建、置钉路径可视化设计和虚拟演示,使操作过程简单、直观而精确,不需要线形和角性参数的测量;加上导向抓持装置提供的稳定性,使该技术具有很好的临床应用前景。 相似文献
22.
微创锁定加压接骨板内固定治疗胫骨骨折 总被引:2,自引:1,他引:1
臀肌挛缩症的手术治疗方法较多,我们采用大转子后上方双侧小“S”微创切口,每侧切口长约2~3 cm,对挛缩组织进行切断,广泛松解,重症患者行臀中小肌“Z”形延长,松解髋关节囊,并行屈膝屈髋、交叉架腿、划圈征等各项指标评价,配合术后早期功能锻炼治疗,效果满意,1997-2005年8月,共收治2 518例患者,重点研究讨论其病因、分类及治疗。1临床资料1·1诊断臀肌挛缩症的诊断包括病史,特别是婴儿期臀部反复肌肉注射史,特有的外“八”字步态,并膝下蹲困难,站立时的尖臀征,快步行走或跑步时呈跳步征。臀部触诊时可触及索带硬块,划圈征、二郎腿试验及平… 相似文献
23.
Coagulation screening before epidural analgesia in pre-eclampsia 总被引:1,自引:0,他引:1
A questionnaire survey of current practice at a small cross-section of obstetric units, covering 22% of all United Kingdom deliveries, revealed a marked lack of standard practice regarding requests for coagulation screens on pre-eclamptic patients who require epidural procedures. A retrospective audit was therefore carried out on 434 coagulation screens requested for pre-eclamptic patients in whom epidural analgesia might have been considered. Borderline abnormalities of coagulation were found in only 10 patients (2%). Platelet counts of less than 150 x 10(9)/litre were present in 28% of cases. 'Significant' thrombocytopenia (less than 100 x 10(9)/litre) and all coagulation abnormalities were only encountered in severe pre-eclampsia (diastolic blood pressure of greater than 110 mmHg and proteinuria of + + or greater). Furthermore, coagulation abnormality was always associated with a reduced platelet count (mean, 97 x 10(9)/litre). This study would therefore support anaesthetic practice which restricted any requests for coagulation testing to severe pre-eclamptic patients only. For these patients first line testing could be limited to a platelet count. 相似文献
24.
25.
Femoral and lateral cutaneous nerve of the thigh blocks have been performed in a group of 50 children; the method has not previously been described in paediatric practice. The technique was judged to have been successful in 48 (96%) of the children. There were no early or late complications. It is concluded that these blocks are easy to perform, even in small children and infants, and that they can produce reliable postoperative analgesia for a variety of orthopaedic and plastic procedures. 相似文献
26.
小骨窗术和碎吸术治疗脑出血的临床应用研究 总被引:2,自引:0,他引:2
目的对比研究颅内血肿小骨窗清除术和颅内血肿(钻孔)碎吸清除术治疗脑出血的疗效。方法87例脑出血患者分为小骨窗组(行颅内血肿小骨窗清除术)、碎吸组(行颅内血肿碎吸清除术)和对照组(行内科保守治疗)。分别比较小骨窗组、碎吸组、保守组治疗前后的GCS评分及3组的GCS评分差。采用t检验、χ2检验和单因素方差分析比较。结果小骨窗组、碎吸组与保守组的GCS评分差比较均有差异(P<0.05);小骨窗组和碎吸组的GCS评分差比较也有差异(P<0.05)。结论小骨窗颅内血肿清除术、碎吸颅内血肿清除术、内科保守疗法在脑出血治疗中均能发挥一定的作用。小骨窗术和碎吸术在治疗中均能提高疗效、加快神经功能恢复,但小骨窗术较碎吸术能更好地发挥疗效、提高病人的生存质量。 相似文献
27.
Laureano Fernández-Cruz Rebeca Cosa Laia Blanco Sammy Levi Miguel-Angel López-Boado Salvador Navarro 《Journal of gastrointestinal surgery》2007,11(12):1607-1622
Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign
pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach
in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest
single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery
from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic
drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis:
group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients);
group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients);
and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R
0 or R
1 resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection
modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival.
The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic
spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation
in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed
in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication
rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly
higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation
because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap
SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days.
In this series, 27 patients (26.2%) had malignant disease. R
0 resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal
adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant
lesions of the pancreas. 相似文献
28.
经尿道电气化手术治疗112例膀胱肿瘤的临床分析 总被引:1,自引:0,他引:1
目的 :探讨经尿道电气化手术治疗病变局限于膀胱壁内肿瘤的治疗方法。方法:综合采用套切、勾切、气化、凝切及电凝、封闭闭孔神经等技术 ,经尿道根治性电气化手术切除膀胱肿瘤 112例。结果:2例因膀胱穿孔改行开放手术 ,7例需 2次手术完全切除肿瘤 ,全部病例均达到根治性切除目的 ,术后平均留置尿管 3~ 7d。结论 :经尿道电气化切除手术适宜病变局限于膀胱壁内肿瘤的根治性治疗。 相似文献
29.
计算机X线摄影图像的静止滤线栅伪影分析 总被引:1,自引:0,他引:1
目的通过分析计算机X线摄影(CR)系统的采样频率和栅密度频率,提出尽可能有效避免滤线栅伪影出现的抑制方法。方法实际测试不同栅密度的滤线栅与不同规格的成像板(IP)匹配使用,得到不同效果的图像;模拟2种信号频率(即2种栅密度的滤线栅),采用3种采样频率[6、8、10图像空间分辨率(pixels/mm)],得到不同的模拟图像效果。结果通过对比分析模拟图和实际图像,发现在采样频率正好等于信号频率的2倍时,可以得到正确的信号频率,图像清晰,无混淆现象。栅密度〈4LP/mm时,可较好地与14in×14in、10in×12in(1in=2.54cm)IP匹配使用。结论CR系统与普通IP匹配使用合适的采样频率和栅密度频率,可以有效避免滤线栅伪影出现。 相似文献
30.
Steven Elia Peter Liu Carol Chrusciel Alan Hilgenberg Charrisios Skourtis Demetrios Lappas 《Journal canadien d'anesthésie》1989,36(1):2-8
Global coronary blood flow and metabolism were measured in seven patients on the first postoperative day following coronary
revascularization to test the hypothesis that tracheal extubation produces adverse haemodynamic responses akin to those observed
during tracheal intubation. Regional coronary flow and metabolic measurements were made in five of the seven patients. Extubation
from a continuous positive airway pressure (CPAP) of 5 cm H2O was associated with a statistically significant rise in cardiac index from 3.44 ± 0.23 L · min-1 · m-2 to 3.73 ± 0.15L·min-1 ·m-2 related to an increase in stroke index, without significant changes in heart rate, mean arterial and pulmonary capillary
wedge pressure. Consequently the changes in myocardial oxygen consumption (8.52 ± 0.55 to 8.85 ± 0.93 ml · min-1) and coronary blood flow (172 ± 18 to 179 ± 17 ml·min-1) were less prominent than those reported during intubation, where substantial rises in myocardial oxygen consumption and
coronary flow occurred. Two patients experienced cardiac lactate production but there were no changes in systemic or coronary
haemodynamics, nor were there clinical or electrocardiographic signs of ischaemia. We conclude that extubation does not appear
to be associated with adverse systemic or coronary haemodynamic responses in patients following coronary bypass grafting.
However, the revascularized myocardium may remain vulnerable to anaerobic metabolism in the immediate postoperative period.
Pour savoir si comme ľintubation, ľextubation de la trachée provoque des perturbations hémodynamiques, on a mesuré le métabolisme
et la circulation coronarienne globale chez sept patients, au lendemain ďun pontage aorto-coronarien. On a aussi calculé les
valeurs régionales de ces mêmes variables pour cinq ďentre eux. Ľindex cardiaque de 3.44 ± 0.23 L · min-1 · m-2 sous pression positive en respiration spontanée (CPAP) de 5 cm. H2O s’est élevé à 3.73 ± 0.15 L · min-1 · m-2 post-extubation avec une augmentation significative du volume ďéjection. La fréquence cardiaque et les pressions artérielles
moyennes et capillaires pulmonaires n’ont pas changé. Ainsi ľaugmentation de la consommation ďoxygène du myocarde de 8.52
± 0.55 à 8.85 ± 0.93 ml · min-1 et celle du flot coronarien de 172 ± 18 à 179 ± 17 ml · min-1 ont été moindres que celles, importantes, déjà observées lors de ľintubation. On a noté chez deux patients une production
de lactate par le myocarde, sans changement de ľhémodynamic systémique et coronarienne non plus que de signe clinique ou électrocardiographique
ďischémie. Donc, après un pontage coronarien, ľextubation ne semble pas causer ďeffet néfaste sur les circulations systémique
et coronarienne, toutefois, le myocarde revascularisé peut demeurer sensible au métabolisme anaérobique. 相似文献