全文获取类型
收费全文 | 8624篇 |
免费 | 588篇 |
国内免费 | 89篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 295篇 |
妇产科学 | 291篇 |
基础医学 | 933篇 |
口腔科学 | 159篇 |
临床医学 | 930篇 |
内科学 | 1867篇 |
皮肤病学 | 215篇 |
神经病学 | 860篇 |
特种医学 | 227篇 |
外科学 | 1404篇 |
综合类 | 166篇 |
一般理论 | 3篇 |
预防医学 | 421篇 |
眼科学 | 137篇 |
药学 | 642篇 |
中国医学 | 70篇 |
肿瘤学 | 576篇 |
出版年
2023年 | 43篇 |
2022年 | 104篇 |
2021年 | 218篇 |
2020年 | 105篇 |
2019年 | 196篇 |
2018年 | 233篇 |
2017年 | 165篇 |
2016年 | 186篇 |
2015年 | 254篇 |
2014年 | 312篇 |
2013年 | 433篇 |
2012年 | 560篇 |
2011年 | 624篇 |
2010年 | 376篇 |
2009年 | 355篇 |
2008年 | 518篇 |
2007年 | 505篇 |
2006年 | 520篇 |
2005年 | 460篇 |
2004年 | 447篇 |
2003年 | 326篇 |
2002年 | 311篇 |
2001年 | 275篇 |
2000年 | 216篇 |
1999年 | 217篇 |
1998年 | 61篇 |
1997年 | 60篇 |
1996年 | 54篇 |
1995年 | 34篇 |
1994年 | 45篇 |
1993年 | 44篇 |
1992年 | 100篇 |
1991年 | 102篇 |
1990年 | 104篇 |
1989年 | 97篇 |
1988年 | 80篇 |
1987年 | 71篇 |
1986年 | 58篇 |
1985年 | 56篇 |
1984年 | 54篇 |
1983年 | 37篇 |
1982年 | 16篇 |
1981年 | 25篇 |
1980年 | 20篇 |
1979年 | 40篇 |
1978年 | 23篇 |
1977年 | 20篇 |
1976年 | 23篇 |
1975年 | 19篇 |
1974年 | 23篇 |
排序方式: 共有9301条查询结果,搜索用时 0 毫秒
101.
102.
Risk of deep vein thrombosis following laparoscopic rectosigmoid cancer resection in chinese patients 总被引:1,自引:0,他引:1
Cheung HY Chung CC Yau KK Siu WT Wong SK Chiu E Li MK 《Asian journal of surgery / Asian Surgical Association》2008,31(2):63-68
OBJECTIVE: The aim of this study was to evaluate the incidence of postoperative deep vein thrombosis (DVT) in Chinese patients who underwent laparoscopic resection of rectal or sigmoid cancer in the absence of thromboprophylaxis. METHODS: Patients with adenocarcinoma of the sigmoid colon or rectum scheduled for laparoscopic resection were recruited. Neither chemoprophylaxis nor mechanical methods against DVT were employed. They were scheduled to have routine duplex ultrasound of both lower limbs perioperatively. RESULTS: In a 12-month period, 50 patients were recruited. Postoperative DVT occurred in 19 (38%) patients. None needed anticoagulation. Complete resolution of the thrombus was noted in 10 (53%) patients 12 weeks after operation, and in six patients 36 weeks after operation. Female sex was identified as being associated with a higher incidence of DVT. Age, smoking, preoperative neoadjuvant chemoirradiation, preoperative metastasis, duration of operation, conversion and postoperative complications did not appear to be risk factors for DVT. CONCLUSION: The incidence of asymptomatic calf vein DVT is relatively high after laparoscopic resection for rectosigmoid cancers in the Chinese population. However, complete resolution occurred without the use of anticoagulant therapy in the majority of cases. It is thus difficult to advocate the routine use of anticoagulant prophylaxis. 相似文献
103.
Reduction in nocturnal functional bladder capacity is a common factor in the pathogenesis of refractory nocturnal enuresis 总被引:7,自引:0,他引:7
OBJECTIVE: To evaluate the diurnal and nocturnal bladder reservoir function in patients with refractory primary nocturnal enuresis (PNE). PATIENTS AND METHODS: Ninety-five children (68 boys, 27 girls, mean age 9.3 years) with significant PNE (>/=3 wet nights/week) that was refractory to treatment with desmopressin +/- an enuretic alarm were assessed using detailed recording of voiding frequency and urinary volume both day and night, natural filling cystometry during the day and continuous cystometry with simultaneous electroencephalogram monitoring during sleep at night. RESULTS: Patients could be broadly categorized into two groups. Group A comprised those with normal daytime urodynamics and functional bladder capacity (FBC) on detailed frequency-volume recording, but who developed marked detrusor instability associated with a significant reduction in nocturnal FBC and small-volume voiding only after sleep at night (33 patients, 35%); and group B, those with abnormal daytime urodynamics and with reduced FBC and small-volume voiding both day and night, but who somehow managed to mask their bladder symptoms during the day (62 patients, 65%). There was no evidence of nocturnal polyuria in either group and the ratios of day : night urinary output volumes for type A and type B patients were 1.48 and 1.99, respectively. CONCLUSION: A reduction in nocturnal FBC, either occurring only after sleep at night in association with the appearance of detrusor instability in patients with normal daytime urodynamics and FBC, or as a manifestation of occult voiding dysfunction or bladder outlet obstruction that affects the bladder reservoir function both day and night, appears to be a common factor and probably the main cause for a mismatch between nocturnal urine output and bladder storage capacity in patients with severe bed-wetting that was refractory to treatment. 相似文献
104.
Hsu LW Goto S Nakano T Lai CY Lin YC Kao YH Chen SH Cheng YF Jawan B Chiu KW Chen CL 《Transplant immunology》2007,17(2):137-146
In orthotopic liver transplantation (OLT), tolerance is induced in a certain combination of donors and a recipient in rats and, in some clinical cases, rejection has not occurred in OLT patients after weaning off immunosuppression. However, this mechanism has not yet been elucidated. Among our cases of liver transplantation (LTx), one OLT patient (Patient A) has not required immunosuppressive drugs for the last 5 years, following post-transplant lymphoproliferative disease (PTLD). This patient's serum interleukin-2 levels were undetectable following withdrawal of immunosuppressants. The same serum taken after discontinuing the immunosuppressants inhibited concanavalin A blast cultured cells and up-regulated the IL-4/IFN-gamma gene expression ratio. These results suggested that other proteins were induced following withdrawal of immunosuppressants. Proteomic assay demonstrated 12 differentiated spots exclusive to this patient where immunosuppressants have been discontinued. Haptoglobin, found to have immunosuppressive activity in vitro, may play an important role in the maintenance of drug-free tolerance as a natural immunological suppressor after cessation of immunosuppression. Proteomic analysis will allow us to develop a novel weaning protocol for patients on long-term immunosuppression to avoid major immunosuppressant-related complications. 相似文献
105.
OBJECTIVE: To evaluate the stage- and grade-specific survival rate in patients with upper urinary tract (UUT) transitional cell carcinoma (TCC) after open (ONU) or hand-assisted laparoscopic nephroureterectomy (LNU) with bladder-cuff excision. PATIENTS AND METHODS: From January 1998 to April 2005, 143 patients with UUT-TCC were treated with either ONU or LNU and enrolled in the study. The peri-operative data were collected by retrospective chart review. The recurrence, metastasis and survival rate were calculated. RESULTS: The 5-year disease-specific survival of patients with pT1 disease was 88.1% after ONU and 92.0% after LNU (P = 0.745); the respective values for patients with pT2 were 11/17 and 12/15 (P = 0.874), and for pT3 were six/11 and 12/15 (P = 0.476). The incidence of bladder recurrence within 2 years after surgery was 24.7% for ONU and 19.7% for LNU (P = 0.475). CONCLUSION: The results were similar after ONU or LNU with bladder-cuff excision; bladder-cuff excision using a hand-assisted device is effective and serves as a treatment option for patients with UUT-TCC. 相似文献
106.
股骨转子间骨折与股骨颈骨折内固定失效后行人工髋关节置换术的比较 总被引:21,自引:1,他引:21
目的将股骨转子间骨折行动力髋部螺钉(DHS)内固定术后的人工髋关节置换术与股骨颈骨折AO螺钉内固定术后行全髋关节置换术的临床结果相比较,总结股骨转子间骨折行DHS内固定术后的人工髋关节置换术经验以及治疗过程中的困难和随访结果。方法将1984年6月~2001年8月有完整资料的19例股骨转子间骨折行DHS内固定术后和配对的19例股骨颈骨折AO螺钉内固定术后行人工髋关节置换术的结果进行比较。使用SPSS软件中的配对T检验方法对本组病人的年龄、性别、DHS失效的原因、骨折至关节置换术时间、早期并发症、失血、手术时间及临床Harris的评分进行统计分析。结果在DHS组中,术后早期并发症(术中股骨近端骨折或术后髋关节脱位)的发生率明显高于AO螺钉组(0.01
相似文献
107.
Chiu DT Hu G Wu J Rhee S Rogers L Gorlick N 《Journal of reconstructive microsurgery》2002,18(6):503-508
A new extended rat-ear flap model, with both an axial and a random component, is described. The flap is based on an axial supply by the posterior auricular artery and the posterior facial vein. The random portion, consisting of the rat dorsum, is capable of being supercharged at two separate sites-in the scapular and pelvic regions. There are several advantages to this composite flap. It is a combined axial and random flap. When used as a free flap, the viability of the axial portion serves as an indicator for anastomotic patency. The random portion allows for the investigation of the effects of pharmaceutical manipulation or surgical intervention, e.g., flap supercharging. The results indicate that the axial supply alone can cover approximately 50 percent of the extended rat-ear flap. Moreover, adding supercharging perforators to the random portion significantly increases the area of flap survival. Of interest, an axial vascular supply, coupled with more distal dorsal perforators (pelvic) than proximal (scapular) perforators, may increase survival for the so-called "watershed" area in the middle of the random portion of the flap. Additionally, this study also investigated the relative importance of arterial supply vs. venous drainage, using the extended rat-ear flap model. The flap was either supercharged with both the perforators of the scapular and pelvic arteries, or both scapular and pelvic veins. The results of the study suggests that augmenting venous drainage provides statistically significant improvement (87 percent vs. 51.6 percent) in increasing flap survival, when compared to augmenting the arterial supply. Arterial supercharging provided no improvement in flap survival, when compared to no supercharging (axial vessels + arterial supercharging, 51.6 percent vs. axial vessels alone, 49.9 percent). The results also suggest that providing adequate venous outflow is more important than providing additional arterial blood, and that impaired venous outflow may contribute to some cases of flap failure. However, it should be kept in mind that the best flap survival occurs with both arterial and and venous supercharging. 相似文献
108.
Bittira B Kuang JQ Al-Khaldi A Shum-Tim D Chiu RC 《The Annals of thoracic surgery》2002,74(4):1154-9; discussion 1159-60
BACKGROUND: We have previously reported that marrow stromal stem cells (MSCs), when implanted into myocardium, can undergo milieu-dependent differentiation to express phenotypes similar to the cells in the immediate microenvironment. We tested the hypothesis that by in vitro preprogramming of MSCs, we may be able to guide their differentiation to express a therapeutically desirable phenotype that is different from those in their microenvironment. METHODS: MSCs were isolated from isogenic Lewis rats, culture expanded, and labeled with beta-gal using retrovirus carrying the lac-Z gene. A subset of the transfected MSCs was then treated with 5-aza-2'deoxycytidine (5-aza). Three weeks after the left ventricles were cryoinjured, either 5-aza-pretreated (n = 10) or untreated (n = 8) MSCs were injected into the myocardial scar. The hearts were harvested 4 to 8 weeks later and stained immunohistochemically for phenotypic markers. RESULTS: The labeled MSCs within the scars that were 5-aza pretreated appeared to be morphologically distinct from the untreated ones. The treated cells (8/10 rats) appeared more myotube-like, with elongated nuclei, linearly aligned with one another, and stained positive for the cardiomyocyte-specific marker troponin I-C. Untreated MSCs (5/8 rats), in contrast, were poorly differentiated, and some appeared to express other phenotypes seen in the scar tissue. CONCLUSIONS: Our findings indicate that in cellular cardiomyoplasty using MSCs, one may select different strategies to achieve specific therapeutic goals. By milieu-dependent differentiation, unmodified MSCs may augment myocardial angiogenesis and myogenesis, whereas converting scar into myogenic tissue may be facilitated by preprogramming of MSCs before implantation. 相似文献
109.
From January 1993 to September 2002, 931 patients suffered from intertrochanteric fracture and subrochanteric fracture received open reduction and internal fixation with APGN in our institute. Among these patients, 16 patients (1.7%) developed a femoral shaft fracture after the initial fixation with APGN. Removal of the APGN, closed reduction and fixation with long Gamma nail (LGN) was performed in all the 16 patients. The patients were followed for 12-60 months (average, 39.8 months). The union time of fracture was 12-24 weeks (average, 18.5 weeks) for femoral shaft fractures and 12-20 weeks (average, 16 weeks) for peritrochanteric fractures. Two early complications were noted, including one superficial (6%) infection and one deep (6%) infection. Two malunions (12.5%) developed with no definite functional impairment. The functional results using the Harris hip score were good to excellent. In conclusion, closed reduction and internal fixation with a LGN is very effective in the management of a femoral shaft fracture, a complication of a previous APGN that had been initially used for stabilisation of a pertrochanteric fracture. 相似文献
110.
BACKGROUND: The purpose of this report is to present long-term outcomes of gamma knife radiosurgery for intracranial mature teratoma after debulking surgery. METHODS: Three patients with intracranial mature teratoma had initial target volumes of 5.4, 18.7, and 5.1 cm(3), respectively, and were treated by gamma knife radiosurgery between 1993 and 2004. Marginal doses of 17, 12.5, and 13.5 Gy, respectively, were delivered to the tumors at isodose levels of 50%, 50%, and 62%, respectively. The first patient received radiosurgery after surgical removal and conventional radiotherapy. The second patient received similar management, including surgery and radiotherapy, with tumor recurrence. Two additional operations and subsequent radiosurgery were performed on this patient. Based on the favorable results of the first 2 patients, we performed radiosurgery instead of conventional radiotherapy after subtotal surgical removal in the last patient. By reviewing literatures concerning the therapeutic modalities and the long-term results of our 3 patients, we discuss the role of radiosurgery in treating intracranial mature teratoma. RESULTS: A follow-up period of 121, 89, and 31 months, respectively, demonstrated tumor volume reduction rates of 70%, 89%, and 48%, respectively. No evidence of further tumor progression and no radiosurgery-related complication or morbidity was noted. The school performances of the affected children are all above average. CONCLUSIONS: Gamma knife radiosurgery provides a safe and effective alternative as the adjuvant treatment of intracranial mature teratoma after surgical debulking. Previous conventional radiotherapy does not alter final tumor control. Radiosurgery should be considered when residual tumor growth continues with no related symptoms or evaluations of tumor markers during follow-up. 相似文献