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81.
《The spine journal》2021,21(12):2097-2103
BACKGROUND CONTEXTOsseointegration is a pivotal process in achieving a rigid fusion and ultimately a successful clinical outcome following interbody fusion surgery. Advancements in 3D printing technology permit commonly used titanium interbody spacers to be designed with unique architectures, such as a highly interconnected and specific porous structure that mimics the architecture of trabecular bone. Interbody implants with a microscale surface roughness and biomimetic porosity may improve bony ongrowth and ingrowth compared to traditional materials.PURPOSEThe purpose of this study was to compare the osseointegration of lumbar interbody fusion devices composed of surgical-grade polyetheretherketone (PEEK), titanium-alloy (TAV), and 3D-printed porous, biomimetic TAV (3DP) using an in vivo ovine model.STUDY DESIGNIn Vivo Preclinical Animal StudyMETHODSEighteen sheep underwent two-level lateral lumbar interbody fusion randomized with either 3DP, PEEK, or TAV interbody spacers (n=6 levels for each spacer per time point). Postoperative time points were 6 and 12 weeks. Microcomputed tomography and histomorphometry were used to quantify bone volume (BV) within the spacers (ingrowth) and the surface bone apposition ratio (BAR) (ongrowth), respectively.RESULTSThe 3DP-treatment group demonstrated significantly higher BV than the PEEK and TAV groups at 6 weeks (77.3±44.1 mm3, 116.9±43.0 mm3, and 108.7±15.2 mm3, respectively) (p<.05). At 12 weeks, there were no BV differences between groups (p>.05). BV increased in all groups from the 6- to 12-week time points (p<.05). At both time points, the 3DP-treated group (6w: 23.6±10.9%; 12w: 36.5±10.9%) had significantly greater BAR than the PEEK (6w: 8.6±2.1%; 12w: 14.0±5.0%) and TAV (6w: 6.0±5.7%; 12w: 4.1±3.3%) groups (p<.05).CONCLUSIONS3DP interbody spacers facilitated greater total bony ingrowth at 6 weeks, and greater bony ongrowth postoperatively at both 6 and 12 weeks, in comparison to solid PEEK and TAV implants.CLINICAL SIGNIFICANCEBased on these findings, the 3DP spacers may be a reasonable alternative to traditional PEEK and TAV spacers in various clinical applications of interbody fusion.  相似文献   
82.
《The spine journal》2021,21(11):1857-1865
BACKGROUND CONTEXTThere are few studies of the radio-clinical outcomes of cement-augmented cannulated pedicle screw (CPS) fixation in osteoporotic patients.PURPOSETo compare the radiological and clinical outcomes between groups receiving cement-augmented CPS and solid pedicle screws (SPS) in lumbar fusion surgery.STUDY DESIGN/SETTINGRetrospective comparative studyPATIENT SAMPLEA total of 187 patients who underwent lumbar fusion surgery for degenerative spinal stenosis or spondylolisthesis from 2014 to 2019.OUTCOME MEASURESRadiological evaluation included screw failure, cage failure, rod breakage, and fusion grade at postoperative 6 months and 1 year. Pre- and postoperative visual analog scales for back pain (VAS-BP), leg pain (VAS-LP), Korean Oswestry disability index (K-ODI), and postoperative complications were also compared.METHODSOutcomes of patients with high risk factors for implant failure [old age, osteoporosis, autoimmune disease or chronic kidney disease (CKD)] who underwent open transforaminal lumbar interbody fusion with cement-augmented CPS fixation (Group C, n=55) or SPS fixation (Group S, n=132) were compared.RESULTS324 pedicle screws in Group C and 775 pedicle screws in Group S were analyzed. Group C had a significantly higher average age and lower T-score, and included more patients with autoimmune disease and CKD than group S (all p<.05). Clear zones, screw migration and loss of correction were significantly less frequent in Group C (all p<.05). Thirteen screw breakages were observed; they were only in Group C (4.0%) and all were in the proximal of the two holes. Interbody and posterolateral fusion rates were not significantly different. At last follow-up, all clinical parameters including VAS-BP, VAS-LP, and K-ODI scores had improved significantly in both groups. Postoperative complications were not significantly different in the two groups.CONCLUSIONIn lumbar fusion surgery, using cement-augmented CPS in high-risk groups for implant failure could be a useful technical option for reducing acute radiological complications and obtaining clinical results comparable to those obtained using SPS in patients with low risk of implant failure.LEVEL OF EVIDENCELevel 4  相似文献   
83.
目的评价腹壁疝内镜下全腹膜外Sublay(TES)手术的效果并总结经验。方法回顾性总结国内10所医院自2016年3月至2019年7月115例腹壁疝内镜下TES手术的患者资料。分析患者情况、疝的特点、手术经过和结果。结果115例计划实施TES的患者中,因严重腹膜破损中转为IPOM修补患者1例,其余均成功手术。可以缝合缺损患者108例(94.74%),需要永久补片固定患者15例(13.16%)。放置引流患者76例(66.67%),中位手术时间为144 min,术中无严重并发症发生。随访时间3~45个月,总并发症发生率为20例(17.54%),其中出现血清肿患者5例(4.38%)。绝大多数患者术后仅出现轻微疼痛,未出现慢性疼痛。结论在腹壁疝的治疗中,对熟悉腹壁解剖的外科医师而言,TES是一种有效、安全的修复手段。在熟悉手术的基础上适应症可逐步拓展。  相似文献   
84.
To aim of the present paper was to introduce a novel fixation technique for the treatment of inferior pole fracture of the patella. We performed a prospective observational study of consecutive cases of inferior pole fracture of the patella that were treated at our institution between January 2018 and June 2019. The patients include three men and one woman, with an average age of 47 years (range: 42–59 years). All patients were treated with the novel rim plating fixation technique for preserving the inferior pole of the patella. During the surgery, a 2.4 mm straight locking compression plate was contoured to adapt to the arc of the lower half of the patella as the rim plate. After reduction of the fracture, the rim plate was fixed to the proximal fragment of the patella through multiple locking screws, against the continuous pull of the patellar tendon. The rim plate encircles and constricts the inferior pole fragments, functioning as a compression and blocking construct. If necessary, an additional anterior tension band or mini locking plate can be used to further prevent anterior displacement of the inferior pole fragments. Under this rigid fixation, motion of the knee and full weight‐bearing were encouraged postoperatively. The patients were followed up monthly until 12 months after surgery. The time to achieve 90°pain‐free, full range of motion of the knee, and fracture healing, were recorded. Related complications were monitored, including infection, loss of reduction, fixation failure, anterior knee pain, and soft‐tissue irritation. The modified Cincinnati knee rating system was used for knee function assessment. The average operative time was 58.8 min (range: 52–63 min). The average blood loss was 59.8 mL (range: 45–71 mL). For all patients, pain‐free 90° range of motion was restored in 2–4 weeks, and the full range of motion was restored in 8–11 weeks. All patients achieved bone union in 6–9 weeks with no displacement of the fragments or breakage of the implant. No patient complained of anterior knee pain or soft‐tissue irritation. The modified Cincinnati score at 12‐month follow up demonstrated excellent outcomes in all four patients. The rim plating technique may be a feasible option for the treatment of the inferior pole fracture of the patella.  相似文献   
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89.
目的 探讨体外冲击波碎石 (ESWL)导致机体感染的可能性及测定尿液内毒素的价值和意义。方法  16 4例上尿路结石病人分成 5组。A组 :4 8例肾结石病人 ,结石 1- 4枚 (直径均≤ 2cm)。B组 :2 4例肾结石病人 ,结石 1- 3枚 (直径均 >2cm)。C组 :2 2例肾结石病人 ,结石 1- 3枚 ,伴 1- 2枚输尿管结石。D组 :51例输尿管结石病人 ,结石 1- 3枚 (直径为 0 5- 1 2cm)。E组 :19例复杂性肾结石病人。除A组外均有不同程度尿流梗阻。ESWL治疗前均无尿路感染。所有患者ESWL治疗前后取血、尿作细菌培养及以鲎试验测内毒素浓度。结果 所有病人ESWL治疗前、后血液内毒素浓度均无显著性变化 ,血液细菌培养均为阴性。B、C和E组ESWL治疗后尿液内毒素均较治疗前显著性升高。A和D组ESWL治疗前后尿液内毒素浓度均无显著性改变。ESWL治疗后B、C和E组尿液细菌培养阳性率较A和D组显著升高 ,或非常显著升高。结论 直径≤ 2cm、对引流系统无明显影响的肾结石或直径 0 5- 1 2cm的输尿管结石 ,ESWL治疗导致泌尿系感染的可能性较小 ;但复杂性、直径 >2cm的肾结石、或肾结石伴输尿管结石 ,即使ESWL治疗前无菌尿症 ,ESWL导致泌尿系感染的可能性大 ,预防性使用抗生素是必要的。另外 ,尿液内毒素测定是诊断ESWL病人泌尿系是否感染的一个  相似文献   
90.
目的 对慢性支气管炎急性期和缓解期患者外周血B细胞和T细胞CD分子检测并了解其变化。方法 用荧光单抗CD19^ 、CD4^ 、CD8^ /CD28^ 对B细胞和T细胞亚群进行标记和记数。结果 慢性支气管炎急性发作期患者与缓解期患者相比,体内辅助性T淋巴细胞无明显变化,抑制性T淋巴细胞增加,细胞毒性T淋巴细胞减少,B淋巴细胞二者间无差异。结论 因慢性支气管炎急性期危重病人T淋巴细胞亚群变化,造成免疫功能紊乱。因此,在治疗疾病过程中,除对症处理外,另须配合使用提高免疫功能的药物,改善免疫功能。  相似文献   
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