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991.
The objective of this research was to induce a new animal model of osteonecrosis of the femoral head (ONFH) by microwave heating and then repair with tissue engineered bone. The bilateral femoral heads of 84 rabbits were heated by microwave at various temperatures. Tissue engineered bone was used to repair the osteonecrosis of femoral heads induced by microwave heating. The roentgenographic and histological examinations were used to evaluate the results. The femoral heads heated at 55 degrees C for ten minutes showed low density and cystic changes in X-ray photographs, osteonecrosis and repair occurred simultaneously in histology at four and eight weeks, and 69% femoral heads collapsed at 12 weeks. The ability of tissue engineered bone to repair the osteonecrosis was close to that of cancellous bone autograft. The new animal model of ONFH could be induced by microwave heating, and the tissue engineering technique will provide an effective treatment.  相似文献   
992.
Regeneration of sweat glands after deep burns has been an unsolved problem. Owing to lack of perspiration, survivors of an extensive deep burn injury are leading a miserable life in sultry months. It was our contemplation to solve this problem by inducing bone marrow mesenchymal stem cells (MSCs) to acquire the phenotype of sweat gland cells in vitro. Then these cells were transplanted into fresh skin wounds resulting from excision of anhydrotic scars after healing of deep burn injury in five patients. Two to 12 months after the procedure, it was proved that there was recovery of perspiration function in all the MSCs' transplanted areas, as evidenced by positive iodine–starch perspiration test. Histological and biochemical observation confirmed the involvement of MSCs transformed sweat gland cells in the recovery of functional sweat glands, and the components of sweat collected from these areas were similar to that collected from normal skin. This is the first report of successful transplantation of MSCs in regenerating functional sweat glands, which may help solve the problem of depletion of sweat glands in patients surviving extensive deep burns in the future.  相似文献   
993.

Background

Robotic-assisted laparoscopic radical prostatectomy (RALP) has been rapidly adopted despite a daunting learning curve with bladder neck dissection as a challenging step for newcomers.

Objective

To describe an anatomic, reproducible technique of bladder neck preservation (BNP) and associated perioperative and long-term outcomes.

Design, settings, and participants

From September 2005 to May 2009, data from 619 consecutive RALP were prospectively collected and compared on the basis of bladder neck dissection technique with 348 BNP and 271 standard technique (ST).

Surgical procedure

RALP with BNP.

Measurements

Tumor characteristics, perioperative complications, and post-operative urinary control were evaluated at 4, 12 and 24 months using (1) the Expanded Prostate Cancer Index (EPIC) urinary function scale scored from 0–100; and (2) continence defined as zero pads per day.

Results and limitations

Mean age for BNP versus ST was 57.1 ± 6.6 yr versus 58.9 ± 6.7 yr (p = 0.033), while complication rates did not vary significantly by technique. Estimated blood loss was 183.7 ± 95.8 ml versus 224.6 ± 108 ml (p = 0.938) in men who underwent BNP versus ST. The overall positive margin rate was 12.8%, which did not differ at the prostate base for BNP versus ST (1.4% vs. 2.2%, p = 0.547). Mean urinary function scores for BNP versus ST at 4, 12, and 24 mo were 64.6 versus 57.2 (p = 0.037), 80.6 versus 79.0 (p = 0.495), and 94.1 versus 86.8 (p < 0.001). Similarly, BNP versus ST continence rates at 4, 12, and 24 mo were 65.6% versus 26.5% (p < 0.001), 86.4% versus 81.4% (p = 0.303), and 100% versus 96.1% (p = 0.308).

Conclusions

BNP versus ST is associated with quicker recovery of urinary function and similar cancer control.  相似文献   
994.
目的 探讨红细胞生成素(EPO)对高糖诱导下的肾小管上皮细胞转分化的影响。 方法 体外培养人肾小管上皮细胞株(HK-2细胞),分为正常对照组、渗透浓度对照组、高糖组、高糖+EPO(5 U/ml)组和高糖+EPO(10 U/ml)组。RT-PCR法检测各组细胞α平滑肌肌动蛋白(α-SMA)、转化生长因子β1(TGF-β1)、Smads信号蛋白2(Smad2)及整合素连接激酶(ILK)的mRNA表达。细胞免疫荧光法检测细胞TGF-β1及α-SMA的蛋白表达。 结果 RT-PCR结果显示,相对于对照组,高糖组细胞α-SMA、TGF-β1、Smad2、ILK的mRNA表达均显著上调(P < 0.01)。细胞免疫化学也显示,高糖组TGF-β1和α-SMA的蛋白表达较对照组显著上调(P < 0.01),而高糖+EPO(5 U/ml)组和高糖+EPO(10 U/ml)组上述指标的表达均显著低于高糖组(均P < 0.01)。 结论 EPO能抑制高糖诱导的肾小管上皮细胞转分化,可能与其抑制TGF-β1、Smad2及ILK表达有关。  相似文献   
995.

Background

We investigated the safety of treatment of symptomatic intracranial atherosclerotic stenoses with the Gateway-Wingspan system and its initial effect on prevention of ischemic events.

Methods

Twenty-seven cases of symptomatic intracranial atherosclerotic stenoses were treated with angioplasty with a Wingspan stent. Location of stenoses, extent of stenoses before and after angioplasty, success rate of treatment, occurrence of procedural complications, and changes in recurrence of symptoms of ischemic events 30 days after treatment were recorded.

Results

Twenty-nine angioplasties with the Wingspan system were successfully carried out in 29 stenoses in 27 patients. Of 29 stenoses, 17 were in the posterior circulation, and 12, in the anterior circulation. The degree of stenoses was reduced from baseline 71.8% (56%-87.8%) to 24.9% (0%-45%) after stenting. Complications were seen in four patients (14.8%), 3 of which were lesion-related infarction of a perforated artery, and 1 was a non-lesion-related infarction. Two complications led to transient neurologic dysfunction, one led to defect of the visual field, and one led to hemiplegia. The prevalence of morbidity and serious morbidity were 7.4% and 3.7%, respectively, and no death occurred. No new ischemic events happened during 30 days after stenting.

Conclusion

Angioplasty with the Wingspan system to treat symptomatic intracranial atherosclerotic stenoses appears to be safe. Its initial effect on prevention of ischemic events is acceptable.  相似文献   
996.
997.
Background and purpose Stress shielding from rigid internal fixation may lead to refracture after removal of the osteosynthesis material. We investigated the effect of a low-rigidity (Ti-24Nb-4Zr-7.9Sn) intramedullary nail regarding stress shielding and bone healing of osteoporotic fractures in the rat.Methods 40 female Sprague-Dawley rats, aged 3 months, were divided into the following groups: sham-operation (SHAM) (n = 10), ovariectomized (OVX) (n = 10) and OVX-fracture (n = 20). 10 SHAM rats and 10 OVX rats were killed after 12 weeks to provide biomechanical data. Ovariectomy was performed 12 weeks before fracturing both femurs in 20 rats. The left fracture was stabilized with a high-rigidity titanium alloy pin (Ti-6Al-4V; elastic modulus 110 GPa) and the right with a low-rigidity (Ti-24Nb-4Zr-7.9Sn; elastic modulus 33 GPa). The bony calluses were examined by micro-CT at 6 and 12 weeks after fracture, bone volume (BV) and total volume (TV) were determined at the callus region (ROI1) and the total femur (ROI2). Subsequently, the bones were tested mechanically by a three-point bending test.Results In the low-rigidity group, TV (ROI1) increased at 6 weeks, but BV (ROI1), BV (ROI2) were similar but maximum load increased. At 12 weeks, the maximum load and also BV (ROI1, ROI2) were increased in the low-rigidity group.Interpretation The low-rigidity nail manufactured from Ti-24Nb-4Zr-7.9Sn showed better external callus formation, seemed to reduce effects of stress shielding, and reduced bone resorption better than the stiffer nail. The low-rigidity nail was strong enough to maintain alignment of the fracture in the osteoporotic rat model without delayed union.  相似文献   
998.
复发性静脉性溃疡的原因分析及再处理方法   总被引:1,自引:0,他引:1  
目的 分析复发性静脉溃疡的原因及再次手术策略.方法 回顾性分析2000年1月至2010年6月收治的复发性静脉性溃疡患者的临床资料.共73例患者81条肢体入组,男性55例(60条肢体),女性18例(21条肢体),平均年龄52.6岁(31~73岁).所有患者入院前均因下肢静脉溃疡接受过一次或数次手术.溃疡复发距上次手术8~37个月,平均10.6个月;溃疡直径1.3~6.5 cm,平均3.7 cm.再次手术前多普勒超声发现小腿交通静脉反流57条肢体(70.4%),原发性深静脉瓣膜功能不全38条肢体(46.9%),DVT后遗症16条肢体(19.8%),大隐静脉属支残留11条肢体(13.6%),大隐静脉主干再通或残留8例(9.9%).针对存在的病因采取大隐静脉高位结扎抽剥及属支结扎、内镜深筋膜下交通静脉结扎、溃疡周边环形缝扎、曲张静脉环形缝扎加切除、深静脉瓣膜修复术以及穿着弹力袜等治疗措施.结果 随访3~60个月,平均37.3个月.3个月时溃疡平均直径明显缩小,6个月时溃疡完全愈合,血流动力学指标明显改善.1年后3条肢体(3.7%)溃疡再次复发.结论 小腿交通静脉功能不全、深静脉瓣膜功能不全以及大隐静脉再通或属支残留是静脉性溃疡术后复发的主要原因,针对性的冉次手术仍然可以达到满意疗效.  相似文献   
999.
目的探讨腹腔镜肝切除(LH)的安全性、可行性和微创性。方法在2003年11月至2009年3月期间,选择78例患者行腹腔镜肝脏切除术。其中原发性肝癌39例、继发性肝癌10例、肝脏良性肿瘤29例。对其临床资料进行回顾性分析。结果78例肝切除手术在腔镜下全部顺利完成,无中转开腹手术。病灶分别位于Ⅱ(16例)、Ⅲ(24例)、Ⅳ(11例)、Ⅴ(11例)、Ⅵ(9例)、Ⅷ(4例)、Ⅰ(3例)等肝;病灶大小范围0.8~15cm;3个病灶4例、2个病灶8例、其余66例均为单病灶。术前肝功能Child‘A级者52例、Child’B级22例、Child’C级4例。术式包括:左半肝切除7例、左外叶切除14例、肝段切除11例、局部切除39例、腹腔镜直肠癌切除同时行肝转移灶切除7例。断肝方式为超声刀+LigaSure联合分离法,结合内镜下切割缝合器,不阻断第1肝门。仅4例患者需要输血(400~800ml)。术后无创面出血及胆漏等并发症。术后肝功能多在1周左右恢复至手术前水平,无肝功能衰竭发生。结论(1)由于腹腔镜肝切除技术难度大,手术适应证应严格选择,病灶大小和位置是主要的参考指标;(2)腹腔镜肝切除手术对结直肠癌合并局部肝转移和肝功能Child’C级的病例具有较好的微创优势;(3)超声刀+Ligasure联合断肝方法具有止血效果好、解剖结构清晰、术后创面渗出少、肝功能损害轻的优点;(4)手术者应具有丰富的开腹肝切除的经验和娴熟的腹腔镜操作技巧,同时应具备处理肝切除后各种并发症的能力。  相似文献   
1000.
In this prospective study, our aim was to compare the functional results and radiographic outcomes of fusion and Bryan Cervical Disc replacement in the treatment of two-level cervical disc disease. A total of 65 patients with two-level cervical disc disease were randomly assigned to two groups, those operated on with Bryan Cervical Disc replacement (31) and those operated on with anterior cervical fusion with an iliac crest autograft and plate (34). Clinical evaluation was carried out using the visual analogue scale (VAS), the Short Form 36 (SF-36) and the neck disability index (NDI) during a two year follow-up. Radiological evaluation sought evidence of range of motion, stability and subsidence of the prosthesis. Substantial reduction in NDI scores occurred in both groups, with greater percent improvement in the Bryan group (P = 0.023). The arm pain VAS score improvement was substantial in both groups. Bryan artificial cervical disc replacement seems reliable and safe in the treatment of patients with two-level cervical disc disease.  相似文献   
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