全文获取类型
收费全文 | 20196篇 |
免费 | 1242篇 |
国内免费 | 394篇 |
专业分类
耳鼻咽喉 | 195篇 |
儿科学 | 981篇 |
妇产科学 | 373篇 |
基础医学 | 1529篇 |
口腔科学 | 263篇 |
临床医学 | 1733篇 |
内科学 | 1310篇 |
皮肤病学 | 230篇 |
神经病学 | 714篇 |
特种医学 | 1142篇 |
外国民族医学 | 4篇 |
外科学 | 5117篇 |
综合类 | 2411篇 |
现状与发展 | 3篇 |
预防医学 | 498篇 |
眼科学 | 154篇 |
药学 | 1037篇 |
14篇 | |
中国医学 | 201篇 |
肿瘤学 | 3923篇 |
出版年
2024年 | 38篇 |
2023年 | 284篇 |
2022年 | 588篇 |
2021年 | 716篇 |
2020年 | 655篇 |
2019年 | 569篇 |
2018年 | 613篇 |
2017年 | 534篇 |
2016年 | 634篇 |
2015年 | 678篇 |
2014年 | 1197篇 |
2013年 | 1196篇 |
2012年 | 1042篇 |
2011年 | 1038篇 |
2010年 | 891篇 |
2009年 | 899篇 |
2008年 | 1008篇 |
2007年 | 1013篇 |
2006年 | 950篇 |
2005年 | 780篇 |
2004年 | 689篇 |
2003年 | 597篇 |
2002年 | 538篇 |
2001年 | 461篇 |
2000年 | 450篇 |
1999年 | 357篇 |
1998年 | 367篇 |
1997年 | 316篇 |
1996年 | 293篇 |
1995年 | 257篇 |
1994年 | 263篇 |
1993年 | 168篇 |
1992年 | 171篇 |
1991年 | 169篇 |
1990年 | 141篇 |
1989年 | 121篇 |
1988年 | 131篇 |
1987年 | 101篇 |
1986年 | 102篇 |
1985年 | 121篇 |
1984年 | 107篇 |
1983年 | 60篇 |
1982年 | 88篇 |
1981年 | 98篇 |
1980年 | 83篇 |
1979年 | 77篇 |
1978年 | 62篇 |
1977年 | 46篇 |
1976年 | 32篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
HyTK基因转移联合丙氧鸟苷对人膀胱癌细胞株EJ体外杀伤作用 总被引:4,自引:1,他引:3
为探索HyTK基因转移对人膀胱癌的治疗作用,采用单纯疱疹病毒胸苷激酶(HSVTK)基因转移联合丙氧鸟苷(Ganciclovir,GCV)对通过逆转录病毒载体转导了HyTK基因的人膀胱癌细胞株EJ细胞(EJ/TK)进行体外杀伤。对分别培养及混合培养的EJ细胞及EJ/TK细胞,用不同浓度GCV进行处理,然后观察细胞形态改变及测定活细胞数量。结果:在GCV作用下,EJ细胞形态及数量与对照组无明显变化;而EJ/TK细胞受到GCV明显杀伤,细胞形态破坏,细胞数量明显减少,含10%EJ/TK的混合培养细胞就可观察到很明显的杀伤作用。表明:转导HyTK基因的EJ细胞获得了对GCV的敏感性,并存在很强的“旁观者效应”。提示HyTK基因转移联合GCV可能适用于人膀胱癌治疗。 相似文献
72.
Eric K. Outwater Katsuyoshi Ito Evan Siegelman C. Edwin Martin Manoj Bhatia Donald G. Mitchell 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1033-1039
The purpose of this study is to describe a subset of atypical hepatic hemangiomas that enhance rapidly and diffusely and to determine whether heavily T2-weighted images could distinguish between atypically enhancing liver hemangiomas and hypervascular malignancies. A retrospective search of MR records identified seven patients with liver hemangiomas that demonstrated diffuse early enhancement and 23 patients with biopsy-proven malignant liver lesions that were hypervascular on dynamic gadolinium-enhanced MR images. Quantitative analysis of signal intensity measurements was performed on the T2-weighted images, heavily T2-weighted (TE < 140), and dynamic gadolinium-enhanced images. Blinded reader comparison of the T2-weighted images and gadolinium-enhanced images was performed. Hypervascular hemangiomas enhanced to a greater degree than hypervascular malignant liver lesions on the early phase gadolinium-enhanced images. Perilesional parenchymal enhancement was demonstrated in five cases of rapidly enhancing hemangiomas. Signal intensity and contrast-to-noise ratios on the heavily T2-weighted images of the hemangiomas were significantly greater than that of the hypervascular malignant lesions (P < .05). Hemangiomas were differentiated from the hypervascular malignant liver lesions with high accuracy (97–100%) by three blinded readers based on the T2-weighted images. A subset of hemangiomas have atypical rapid diffuse enhancement on dynamic gadolinium-enhanced images. These atypical hemangiomas can be distinguished from hypervascular malignant liver lesions on T2-weighted MR images. 相似文献
73.
S. Chooramani Gopal A. N. Gangopadhyaya S. N. Gupta G. D. Singhal 《Pediatric surgery international》1991,6(6):438-441
Our experience of single-stage repair of severe hypospadias (penoscrotal, scrotal, and perineal) in 30 children using urinary bladder mucosa for urethroplasty is reported. These children had severe chordee, small prepuce, and often ventral transposition of the penis with bifid scrotum where Devine and Horton, Asopa, or Duckett techniques are not so suitable. The graft uptake was uniformly satisfactory. Ten patients had complications; most of the fistulae healed spontaneously. Surgical intervention was required in 2 cases only: 1 for a fistula and another for a stricture with fistula. Meatal stenosis, seen in 4 cases, led to delayed distal fistulae in 2, which healed spontaneously with meatal dilatation. Regular dilatation of the external meatus is recommended to prevent this problem. 相似文献
74.
Ken Kodama Osamu Doi Masahiko Higashiyama Hideoki Yokouchi Keiko Kuriyama 《Surgery today》1997,27(12):1123-1130
Between 1969 and 1995, 180 patients underwent complete resection of lung metastases during initial thoracotomy at our institute,
involving the resection of 917 pulmonary nodules at 202 thoracotomy procedures. The overall postmetastasectomy 5- and 10-year
survival rates were 46% and 30%, respectively. Of 111 patients who underwent segmentectomy and/or local excision, 57 had multiple
metastases, 39 of whom were treated by Nd:YAG laser after 1986, and 18 by conventional procedures before 1985. The average
number of tumors resected per patient treated with the Nd:YAG laser was significantly greater than that of those treated with
conventional procedures. However, the survival curve of the laser-treated group was better than that of the laser-nontreated
group. Moreover, slightly better survival was achieved in patients operated on after 1992 compared with those operated on
before 1991. We conclude that the laser technique may be warranted to afford complete resection of metastases and adequate
pulmonary reservation in combination with a selected approach for thoracotomy under the exact detection of tumor localization
using the most recent high-quality computed tomography (CT) scan. Furthermore, a one-stage operation to control synchronous
intra- and extrapulmonary malignamcies may become a possible option in combination with selective adjunctive therapy. 相似文献
75.
76.
随机选择经长期随访证实的滤泡性甲状腺癌和腺瘤各10例,正常甲状腺组织5例作为对照。按Ploton的染色方法和Crocker推荐的计数方法分别计算三组每例各50个细胞的Ag-NOR嗜银颗粒平均数,再算出三组各自的AgNOR均数,经统计学检验三者有极显著性差异。可望成为甲状腺滤泡性肿瘤良恶鉴别的一项辅助指标。 相似文献
77.
Laparoscopic cryosurgery for hepatic tumors 总被引:2,自引:0,他引:2
Background: Hepatic cryosurgery has been shown to be a safe technique that may be well suited to a laparoscopic approach.
Methods: The technical feasibility and safety of laparoscopic cryosurgery was explored first in a pig model. Thereafter we performed
the first successful case of laparoscopic hepatic cryosurgery at our institution.
Results: In the animal model, we found that it is possible to safely identify, target, and cryoablate specific lesions in the liver.
Temperature in the peritoneal cavity remained above 35°C, and pathologic examination of the abdominal wall around the cryoprobe
site revealed no damage. We also successfully treated a 62-year-old man with a metastatic colorectal carcinoma deep in the
right lobe of the liver with laparoscopic cryosurgery using a transpleural approach.
Conclusion: We conclude that laparoscopic cryosurgery is feasible for lesions anywhere in the liver. For lesions high on the dome of
the liver, a transpleural approach may provide better access. 相似文献
78.
椎管内肿瘤显微外科手术治疗 总被引:2,自引:0,他引:2
本组收集自2000年2月至2005年12月我院椎管内肿瘤患者64例,通过显微手术治疗,取得满意效果,报告如下。一、资料与方法1.一般资料:在64例椎管内肿瘤中男性36例,女性28例;年龄最小12岁,最大76岁,平均38岁。2.主要症状与体征:(1)疼痛:疼痛为常见的首发症状,共有18例。常表现为根性疼痛,有时可误诊为肋间神经痛或坐骨神经痛。(2)感觉障碍:常见,共有54例。有不同程度的感觉障碍,表现为有感觉障碍平面并常伴有麻木或束带感。髓内肿瘤则常表现有不同程度的节段性感觉障碍,感觉障碍平面与脊髓肿瘤所在部位相关。(3)运动障碍:有52例入院时在肿瘤压迫… 相似文献
79.
目的 :探讨纤维连接蛋白 (FN)在膀胱癌化疗药物耐受中的作用。方法 :将T2 4膀胱肿瘤细胞分别接种于包被FN、牛血清蛋白 (BSA)的培养板上孵育 2 4h ,加入不同浓度的丝裂霉素C(MMC)作用 2h ,用MTT比色法检测作用后不同时间肿瘤细胞的存活率 ,用ANNEXINⅤ流式细胞分析仪检测不同时间肿瘤细胞的凋亡率。结果 :FN黏附的膀胱肿瘤细胞在不同浓度MMC作用 2h、12h和 2 4h后的平均存活率为 6 8.3%、4 5 .7%及 5 9.1% ,与BSA黏附的膀胱肿瘤细胞平均存活率 4 5 .0 %、2 1.3%、2 6 .6 %比较 ,差异有统计学意义 (P <0 .0 5 )。FN黏附的膀胱肿瘤细胞在不同浓度MMC作用 2h和 12h后平均凋亡率分别为 1.4 %和 1.0 % ,而BSA组的细胞平均凋亡率为4 .9%和 8.2 % ,两组比较差异有统计学意义 (P <0 .0 1)。结论 :与FN黏附后的膀胱肿瘤细胞对化疗药物MMC的敏感性下降 ,细胞存活率增高 ;FN能抑制MMC引起的膀胱肿瘤细胞凋亡 ,产生药物耐受。 相似文献
80.