全文获取类型
收费全文 | 2177篇 |
免费 | 229篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 95篇 |
妇产科学 | 57篇 |
基础医学 | 290篇 |
口腔科学 | 49篇 |
临床医学 | 287篇 |
内科学 | 438篇 |
皮肤病学 | 39篇 |
神经病学 | 100篇 |
特种医学 | 240篇 |
外科学 | 270篇 |
综合类 | 53篇 |
一般理论 | 3篇 |
预防医学 | 163篇 |
眼科学 | 33篇 |
药学 | 119篇 |
1篇 | |
中国医学 | 9篇 |
肿瘤学 | 193篇 |
出版年
2022年 | 10篇 |
2021年 | 28篇 |
2020年 | 30篇 |
2019年 | 37篇 |
2018年 | 52篇 |
2017年 | 37篇 |
2016年 | 44篇 |
2015年 | 50篇 |
2014年 | 53篇 |
2013年 | 72篇 |
2012年 | 55篇 |
2011年 | 64篇 |
2010年 | 61篇 |
2009年 | 95篇 |
2008年 | 80篇 |
2007年 | 106篇 |
2006年 | 57篇 |
2005年 | 95篇 |
2004年 | 59篇 |
2003年 | 74篇 |
2002年 | 59篇 |
2001年 | 70篇 |
2000年 | 56篇 |
1999年 | 64篇 |
1998年 | 90篇 |
1997年 | 90篇 |
1996年 | 73篇 |
1995年 | 66篇 |
1994年 | 47篇 |
1993年 | 57篇 |
1992年 | 30篇 |
1991年 | 38篇 |
1990年 | 30篇 |
1989年 | 59篇 |
1988年 | 43篇 |
1987年 | 42篇 |
1986年 | 34篇 |
1985年 | 38篇 |
1984年 | 29篇 |
1983年 | 32篇 |
1982年 | 20篇 |
1981年 | 20篇 |
1980年 | 29篇 |
1979年 | 19篇 |
1978年 | 13篇 |
1977年 | 19篇 |
1976年 | 14篇 |
1973年 | 16篇 |
1972年 | 15篇 |
1970年 | 13篇 |
排序方式: 共有2453条查询结果,搜索用时 15 毫秒
61.
Laronga C Meric F Truong MT Mayfield C Mansfield P 《American journal of surgery》2000,180(6):769-6; discussion 526-7
BACKGROUND: We investigated the role of observation or insertion of a small French pigtail catheter with Heimlich valve as alternative management to a tube thoracostomy for iatrogenic pneumothorax complicating central venous catheter (CVC) insertion. METHODS: A retrospective review of 9,637 consecutive patients who had had subclavian CVCs inserted on an outpatient basis identified 100 patients with pneumothoraces. Treatment consisted of (1) observation, (2) outpatient insertion of a Heimlich valve, or (3) inpatient tube thoracostomy. RESULTS: The median pneumothorax size was 10% (range 1% to 100%). Fifty-eight patients had observation as initial treatment, and this strategy was successful in 35 (60%). Thirty-four patients were treated initially with Heimlich valves, and this strategy was successful in 29 (85%). Tube thoracostomy as initial therapy was successful in 7 (88%) of 8 patients. Patients in who initial treatment failed were treated with insertion of a Heimlich valve or tube thoracostomy. CONCLUSION: In appropriately selected patients, pneumothorax after insertion of a subclavian CVC can be successfully managed in the outpatient setting with observation. Patients in whom observation fails can be treated with insertion of a Heimlich valve. Tube thoracostomy can be reserved for refractory PTX or emergent situations. 相似文献
62.
Perspectives on colorectal cancer screening: a focus group study 总被引:3,自引:0,他引:3
Vivek Goel MD MSc FRCPC Ross Gray PhD Pam Chart MD CM Marg Fitch RN PhD Fred Saibil MD FRCPC Yola Zdanowicz MA 《Health expectations》2004,7(1):51-60
Objective To assess attitudes and acceptability of Ontario consumers and doctors towards colorectal screening with faecal occult blood testing (FOBT) and colonoscopy. Design, setting and participants Focus groups with gender‐specific samples of the population, high‐risk gastroenterology patients and family doctors. Method Semi‐structured interview guides used by facilitator to lead groups through knowledge of risk factors and prevention of colorectal cancer, the screening modalities, requirements for implementing screening programmes, barriers to screening and preferences towards screening. Main findings There were low levels of knowledge about colorectal cancer and its prevention in the general population. FOBT was an acceptable screening modality, but considerable education about its use and benefits would be necessary to implement a screening programme. Colonoscopy was not perceived to be a good choice for a primary screen in the general population. The high‐risk group supported use of FOBT in the general population and emphasized the need for education. The doctors were more reluctant about screening, requesting clear guidelines. They also identified the time and resources that would be required if a screening programme were initiated. Conclusion While colorectal screening is acceptable in this sample, information and decision aids are required to enable consumers and providers to make effective decisions. Implementation of colorectal screening programmes requires substantial educational efforts for both consumers and doctors. 相似文献
63.
64.
Paclitaxel-based chemoradiotherapy in localized gastric carcinoma: degree of pathologic response and not clinical parameters dictated patient outcome. 总被引:10,自引:0,他引:10
J A Ajani P F Mansfield C H Crane T T Wu S Lunagomez P M Lynch N Janjan B Feig J Faust J C Yao R Nivers J Morris P W Pisters 《Journal of clinical oncology》2005,23(6):1237-1244
PURPOSE: Preoperative chemoradiotherapy may increase the R0 (curative) resection rate, overall survival (OS) duration, and disease-free survival (DFS) duration. We evaluated paclitaxel-based induction chemotherapy and chemoradiotherapy in patients with localized gastric or gastroesophageal adenocarcinoma to determine its feasibility, impact on the R0 resection rate, type of pathologic response, OS, and DFS. PATIENTS AND METHODS: Patients with operable, localized gastric, or gastroesophageal adenocarcinoma were eligible. Staging included endoscopic ultrasonography (EUS) and laparoscopy. Patients received two 28-day cycles of induction chemotherapy of fluorouracil, paclitaxel, and cisplatin followed by 45 Gy of radiation and concurrent fluorouracil plus paclitaxel. The cancer was restaged and surgery was attempted. Postsurgery pathologic findings and R0 resection were correlated with OS and DFS. RESULTS: Forty-one patients were enrolled. Most carcinomas were proximal (83%) and pretreatment stage EUST3 (85%). Forty patients (98%) underwent surgery, and 78% had an R0 resection. We observed a pathologic complete response (pathCR) rate of 20% and a pathologic partial response (pathPR) rate of 15% (< 10% residual cancer cells in the resected specimen). No pretreatment parameter (sex, cancer location, baseline T stage, or baseline N stage) predicted the type of postsurgery pathologic response, OS, or DFS. However, pathCR (P = .02), pathCR + pathPR (P = .006), R0 resection (P < .001), and postsurgery T and N stages (P = .01 and P < .001, respectively) were associated with OS. Same parameters were significantly correlated with DFS. Toxicity was manageable. CONCLUSION: The type of pathologic response but not pretreatment parameters was associated with OS and DFS. Efforts to increase the rate of pathologic response and better systemic cancer control are warranted. 相似文献
65.
66.
L Krishnan W R Jewell C M Mansfield E K Reddy J H Thomas E C Krishnan 《International journal of radiation oncology, biology, physics》1987,13(11):1661-1665
Conservation of the breast in early breast cancer with limited resection and radiation is proving to be as effective as modified radical mastectomy in survival and in loco-regional control. Management at the University of Kansas Medical Center consists of an interstitial implant at the time of lumpectomy to facilitate perioperative irradiation with Iridium-192 to the tumor bed. An axillary node dissection is also performed at that time. Two to 3 weeks later external beam irradiation is delivered to the entire breast. One hundred and twenty-three breasts in 120 patients have been treated between June 1982 and June 1986. There were 49 pathological Stage I, 63 Stage II, 8 Stage III carcinomas, and 3 carcinomas in situ, consisting of 72 T1, 43 T2, 5 T3, and 3 TIS lesions. Patients have been followed for a median of 30 months. One patient had a "true" recurrence in the breast. Another patient developed recurrence in a different quadrant. Ninety percent of the patients had good to excellent cosmetic results, 7% were considered fair, and 3% had poor results. Seven patients developed mild arm edema, 4 were found to have moderate edema, and 1 had severe arm edema. Our preliminary results indicate that interstitial irradiation immediately after excision results in excellent local control, with very satisfactory cosmesis and no morbidity due to the simultaneous excision and irradiation. 相似文献
67.
氯地滴眼液的含量测定 总被引:4,自引:0,他引:4
目的:采用HPLC法测定氯地滴眼液中氯霉素和地塞米松磷酸钠的含量。方法:色谱分析条件:ODS柱作分析柱,流动相为甲醇/水体系,0 ̄8min使用40%甲醇,8 ̄16min使用60%甲醇,流速1ml/min,0 ̄9min240nm紫外检测,:二组分分离良好。各组各组性关系良好,平均回收率氯霉素99.8%(RSD=1.2%,n=5),地塞米松磷酸钠99.4%(RSD=0.7%,n=5),结论:该法用于氯 相似文献
68.
Singapore Indian Eye Study‐2: methodology and impact of migration on systemic and eye outcomes
下载免费PDF全文
![点击此处可从《Clinical & experimental ophthalmology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
69.
范春明 《中国组织工程研究与临床康复》2007,11(24):4806-4809
目的:分析胚胎干细胞和胚胎生殖细胞的生物学特性、体外培养条件、周围微环境对其增殖分化的影响,了解胚胎干细胞和胚胎生殖细胞的关系和应用前景。方法:应用计算机检索万方数据库2000/2007有关生殖细胞、胚胎干细胞、胚胎生殖细胞的相关研究文章,检索词:生殖细胞,胚胎干细胞,胚胎生殖细胞,并限定文章语言种类为中文;同时应用计算机检索PUBMED2000/2006相关文章,检索词:Germ Cells,Primordial germ cells,Embryonic stem cells,Embryonic Germ Cells,限定文章语言种类为“English”。对资料进行初审,纳入标准为有关生殖细胞、胚胎干细胞、胚胎生殖细胞的生物学特性、体外培养及生长抑制因子的作用等相关文章,并查找全文。主要选择基础研究类文章,无论有无对照组均纳入。结果:共检索到相关文章59篇,排除比较陈旧的文章,最后纳入38篇进行总结分析。胚胎干细胞与胚胎生殖细胞分别从附置前早期胚胎内细胞团和早期胎儿生殖嵴原始生殖细胞分离克隆出来,均具有自我更新、无限增殖能力及多向分化潜能,在体外培养条件下可保持稳定的二倍体核型,诱导分化后可形成3种胚胎生殖层。饲养层细胞是人胚胎生殖细胞体外培养的必要条件,常用饲养层细胞有鼠STO细胞系、鼠胚胎成纤维细胞,体外生长所需主要细胞因子包括干细胞生长因子、碱性成纤维细胞生长因子和白血病抑制因子,然而只要在培养基中加入鼠成纤维细胞的上清液和碱性成纤维细胞生长因子,胚胎干细胞可在无饲养层的条件下进行体外培养。结论:胚胎干细胞和胚胎生殖细胞具有相似的增殖特性,一定条件下可以分化为包括生殖细胞在内的所有功能细胞,并可相互转变,在胚胎发育、基因治疗、药物筛选、新药开发、生殖医学及人类疾病的移植治疗中具有广泛的应用前景。 相似文献
70.
The time-course of light-induced potential changes was measured transretinally as a function of flash intensity in the eyecup preparation of dark-adapted Bufo marinus. The electroretinogram (ERG) as indexed by the peak amplitude of the a-wave. and the latency of the a-wave onset yielded action spectra matching that of the red rod pigment (λmax at 502 nm) at low intensities near threshold, but at higher intensities there was evidence of intrusion from the single and principal short-latency, longwave cones (λmax at 575 nm). With uniform illumination of the retina with monochromatic (λ = 502 nm) flashes to isolate the red rod system over a range of 5 log units from threshold to saturation of the a-wave. the latency of the b-wave onset and the latency of the a-wave peak varied linearly with the latency of the a-wave onset. All three measures could be described by linear functions of the inverse cube root of flash intensity, or equivalently by the equation: tmin/t=I1/3(I1/3 + σ1/3). For the mass receptor potential (MRP) isolated with excess Mg2+. the initial segment and functional form of the time-course did not differ from that obtained for the a-wave at the same saturating intensity. The results are consistent with the hypothesis that the dominant mechanism controlling visual latency lies in the photoreceptors and that subsequent proximal transformations of the time-course are linear. 相似文献