全文获取类型
收费全文 | 71794篇 |
免费 | 6900篇 |
国内免费 | 140篇 |
专业分类
耳鼻咽喉 | 982篇 |
儿科学 | 2046篇 |
妇产科学 | 1798篇 |
基础医学 | 10444篇 |
口腔科学 | 1400篇 |
临床医学 | 8684篇 |
内科学 | 14229篇 |
皮肤病学 | 991篇 |
神经病学 | 6154篇 |
特种医学 | 2591篇 |
外国民族医学 | 1篇 |
外科学 | 10684篇 |
综合类 | 1177篇 |
现状与发展 | 1篇 |
一般理论 | 79篇 |
预防医学 | 6643篇 |
眼科学 | 1084篇 |
药学 | 4935篇 |
中国医学 | 98篇 |
肿瘤学 | 4813篇 |
出版年
2023年 | 478篇 |
2022年 | 826篇 |
2021年 | 1864篇 |
2020年 | 1073篇 |
2019年 | 1672篇 |
2018年 | 1972篇 |
2017年 | 1381篇 |
2016年 | 1498篇 |
2015年 | 1701篇 |
2014年 | 2326篇 |
2013年 | 3137篇 |
2012年 | 4411篇 |
2011年 | 4410篇 |
2010年 | 2431篇 |
2009年 | 2041篇 |
2008年 | 3367篇 |
2007年 | 3505篇 |
2006年 | 3264篇 |
2005年 | 3115篇 |
2004年 | 2846篇 |
2003年 | 2631篇 |
2002年 | 2524篇 |
2001年 | 1731篇 |
2000年 | 1736篇 |
1999年 | 1545篇 |
1998年 | 765篇 |
1997年 | 639篇 |
1996年 | 568篇 |
1995年 | 582篇 |
1994年 | 519篇 |
1993年 | 490篇 |
1992年 | 1232篇 |
1991年 | 1164篇 |
1990年 | 1143篇 |
1989年 | 1068篇 |
1988年 | 972篇 |
1987年 | 998篇 |
1986年 | 957篇 |
1985年 | 979篇 |
1984年 | 803篇 |
1983年 | 686篇 |
1982年 | 523篇 |
1981年 | 427篇 |
1980年 | 427篇 |
1979年 | 660篇 |
1978年 | 526篇 |
1977年 | 407篇 |
1976年 | 407篇 |
1974年 | 423篇 |
1972年 | 376篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Hardwick RH Taylor A Thompson MH Jones E Roe AM 《Annals of the Royal College of Surgeons of England》2000,82(1):24-26
Abscesses after appendicitis occur in some patients despite timely surgery and antibiotics. The Streptococcus milleri group of bacteria are commonly associated with gastrointestinal abscesses. This study investigated the relationship between S. milleri and abscess formation after appendicectomy a total of 301 patients (172 males, 129 females, median age 22 years) with appendicitis were identified retrospectively from the hospital PAS computer system who had an appendicectomy and peritoneal bacteriology swabs taken. All but one patient had prophylactic antibiotics. Patients were divided into three groups according to peritoneal bacteriology: group 1 (S. milleri +/- mixed faecal organisms, n = 61); group 2 (mixed faecal organisms, n = 126); and group 3 (sterile, n = 114). The chi squared and Student t-tests were used for statistical analysis. Thirteen (21%) of group 1 patients developed an intra-abdominal abscess compared with 4 (3%) in group 2 and 2 (1.7%) in group 3 (P < 0.0001). There was no difference in the prevalence of gangrenous or perforated appendicitis between groups 1 and 2 (56% versus 52%) but these worse forms of appendicitis were less common in group 3 (22%). Group 1 patients had a mean total hospital stay of 10 days versus 6 days for group 2 and 4 days for group 3 (P < 0.001). S. milleri was associated with a 7-fold increase in abscess formation after appendicectomy and a longer hospital stay. Antibiotic prophylaxis did not prevent this complication. 相似文献
992.
993.
994.
Osteoblast-derived factors induce androgen-independent proliferation and expression of prostate-specific antigen in human prostate cancer cells. 总被引:1,自引:0,他引:1
995.
Phase II study of denileukin diftitox for relapsed/refractory B-Cell non-Hodgkin's lymphoma. 总被引:1,自引:0,他引:1
Nam H Dang Fredrick B Hagemeister Barbara Pro Peter McLaughlin Jorge E Romaguera Dan Jones Barry Samuels Felipe Samaniego Anas Younes Michael Wang Andre Goy Maria A Rodriguez Pamela L Walker Yolanda Arredondo Ann T Tong Luis Fayad 《Journal of clinical oncology》2004,22(20):4095-4102
PURPOSE: Denileukin diftitox is a fusion protein combining diphtheria toxin and interleukin-2 (IL-2) that targets tumor cells expressing the IL-2 receptor. Its efficacy has been shown in CD25+ cutaneous T-cell lymphoma, but not in B-cell non-Hodgkin's lymphoma (NHL). A phase II study was performed to evaluate the efficacy and tolerability of denileukin diftitox for relapsed or refractory B-cell NHL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell NHL were eligible. Tumor CD25 expression was determined by immunohistochemistry or flow cytometry. Denileukin diftitox was administered intravenously at a dose of 18 microg/kg once daily for 5 days every 3 weeks, up to eight cycles. RESULTS: Of the 45 patients assessable for response, 32 (71%) were refractory to the last chemotherapy treatment, and all were previously treated with rituximab. Three complete responses (6.7%) and eight partial responses (17.8%) were observed, for an overall response rate of 24.5%. Nine patients (20%) had stable disease. Objective response rates were similar in CD25+ (22%) and CD25- histologies (29%), as were stable disease rates (22% and 18%, respectively). For responding patients, the median time to treatment failure was 7 months, with a median follow-up in survivors of 18 months (range, 9 to 28 months), and the projected progression-free survival at 20 months was 24% (95% CI, 0% to 60%). Most toxicities were low-grade and transient. CONCLUSION: Denileukin diftitox seems to be effective in relapsed or refractory, CD25+ and CD25- B-cell NHL and is well-tolerated at the dosage evaluated. Evaluation of denileukin diftitox in combination with other agents may be warranted. 相似文献
996.
A S Garden J Harris E E Vokes A A Forastiere J A Ridge C Jones E M Horwitz B S Glisson L Nabell J S Cooper W Demas E Gore 《Journal of clinical oncology》2004,22(14):2856-2864
PURPOSE: To define further the role of concurrent chemoradiotherapy for patients with advanced squamous carcinoma of the head and neck. PATIENTS AND METHODS: The Radiation Therapy Oncology Group developed this three-arm randomized phase II trial. Patients with stage III or IV squamous carcinoma of the oral cavity, oropharynx, or hypopharynx were eligible. Each of three arms proposed a radiation schedule of 70 Gy in 35 fractions. Patients on arm 1 were to receive cisplatin 10 mg/m(2) daily and fluorouracil (FU) 400 mg/m(2) continuous infusion (CI) daily for the final 10 days of treatment. Treatment on arm 2 consisted of hydroxyurea 1 g every 12 hours and FU 800 mg/m(2)/d CI delivered with each fraction of radiation. Arm 3 patients were to receive weekly paclitaxel 30 mg/m(2) and cisplatin 20 mg/m(2). Patients randomly assigned to arms 1 and 3 were to receive their treatments every week; patients on arm 2 were to receive their therapy every other week. RESULTS: Between 1997 and 1999, 241 patients were entered onto study; 231 were analyzable. Ninety-two percent, 79%, and 83% of patients on arms 1, 2, and 3, respectively, were able to complete their radiation as planned or with an acceptable variation. Fewer than 10% of patients had unacceptable deviations or incomplete chemotherapy in the three arms. Estimated 2-year disease-free and overall survival rates were 38.2% and 57.4% for arm 1, 48.6% and 69.4% for arm 2, and 51.3% and 66.6% for arm 3. CONCLUSION: We have demonstrated that three different approaches of concurrent multiagent chemotherapy and radiation were feasible and could be delivered to patients in a multi-institutional setting with high compliance rates. 相似文献
997.
Overexpressed eIF4E is functionally active in surgical margins of head and neck cancer patients via activation of the Akt/mammalian target of rapamycin pathway. 总被引:10,自引:0,他引:10
Cherie-Ann O Nathan Nazanin Amirghahari Fleurette Abreo Xiaohua Rong Gloria Caldito M Lamar Jones Huijuan Zhou Melanie Smith Donnellan Kimberly Jonathan Glass 《Clinical cancer research》2004,10(17):5820-5827
PURPOSE: Overexpression of eIF4E in surgical margins of head and neck cancer patients is an independent risk factor for recurrence. We hypothesize that overexpressed eIF4E is functionally active in tumor margins through activation of the Akt/mammalian target of rapamycin (mTOR) pathway EXPERIMENTAL DESIGN: Western blots and/or immunohistochemistry were performed to determine whether phosphorylation of mTOR and activation of its downstream molecules eIF4E-binding protein-1 (4E-BP1) and p70 S6 kinase and the upstream modulator of mTOR, Akt, were expressed in margins overexpressing eIF4E. RESULTS: There was a significant association between phospho-4E-BP1 and eIF4E expression of a margin or a significant difference in phospho-4E-BP1 expression between the eIF4E-positive and -negative margins (P < 0.01). A significant association between eIF4E and phospho-p70 S6 kinase as well as eIF4E and phospho-mTOR was also noted (P < 0.05). Western blot analysis indicated a highly significant difference in the phosphorylation status of 4E-BP1 between tumors and resection margins. A total of 89% of the 4E-BP1-expressing margins expressed more of the phosphorylated (beta, gamma, and delta) isoforms, whereas 81% of the 4E-BP1-expressing tumors expressed more of the unphosphorylated alpha isoform. A similar difference in Akt activation was noted between eIF4E-positive margins and tumors (P < 0.05). CONCLUSIONS: Overexpression of eIF4E is functionally active in tumor margins through activation of the Akt/mTOR signaling pathway. The greater degree of expression of downstream targets and upstream regulators of mTOR in margins compared with the tumors indicates preferential activation of the Akt/mTOR signaling pathway in margins overexpressing eIF4E. Rapamycin analogs can potentially be used as adjuvant therapy for patients with eIF4E-positive margins. 相似文献
998.
Timothy D Jones Thomas M Ulbright John N Eble Liang Cheng 《Clinical cancer research》2004,10(24):8544-8547
PURPOSE: OCT4 (POU5F1, OCT3) immunostaining highlights pluripotent cells (embryonal carcinoma and seminoma) in primary testicular germ cell tumors, but its relative usefulness in diagnosing intratubular germ cell neoplasia, unclassified (IGCNU) is not well established. The present study aimed to establish OCT4 as a sensitive and specific maker for IGCNU, a putative precursor for adult germ cell tumors. EXPERIMENTAL DESIGN: We evaluated OCT4 immunostaining in 44 cases of IGCNU from patients who had testicular germ cell tumors. In addition, 27 of the 44 IGCNU sections were also examined with antibodies to placenta-like alkaline phosphatase, the most frequently used immunohistochemical marker for intratubular germ cell neoplasia. Sections from the testes of 10 patients who had undergone orchiectomy for hormonal treatment of prostate cancer and from autopsies of 10 patients without histories of germ cell tumors were also examined for OCT4 immunostaining. The immunoreactivity of the autopsy tissues was determined with vimentin staining, and all were reactive. RESULTS: In all 44 of the cases, antibody to OCT4 marked the nuclei of nearly all of the dysplastic cells of intratubular germ cell neoplasia but not non-neoplastic testicular cells. The staining intensity was strong in every case, and there was little or no background staining. All 20 of the control specimens (10 orchiectomy specimens from prostate cancer patients and 10 testes from autopsies) were completely negative for OCT4. The 27 cases that were stained with antiplacenta-like alkaline phosphatase antibodies showed staining of variable intensity in the areas of intratubular germ cell neoplasia, and there was a high level of background staining artifact. CONCLUSIONS: OCT4 is a sensitive and specific maker for intratubular germ cell neoplasia. 相似文献
999.
Ellen L Jones Leonard R Prosnitz Mark W Dewhirst P Kelly Marcom Patricia H Hardenbergh Lawrence B Marks David M Brizel Zeljko Vujaskovic 《Clinical cancer research》2004,10(13):4287-4293
PURPOSE: The purpose of this research was to evaluate toxicity, response, and changes in oxygenation (pO(2)) in patients with locally advanced breast cancer (LABC) treated with concurrent taxol, hyperthermia (HT), and radiation therapy (RT) followed by mastectomy. EXPERIMENTAL DESIGN: Eighteen patients with LABC were enrolled from October 1995 through February 1999. Treatment consisted of taxol (175 mg/m(2)) given every 3 weeks for three cycles. Radiation therapy included the breast and regional nodes with a dose of 50 Gy, followed by a boost to 60-65 Gy for those not undergoing surgery. Mastectomy was performed for patients deemed resectable after this neoadjuvant program. HT was administered twice per week. Oxygenation was measured before the first HT treatment and 24 h after the first HT treatment. RESULTS: Fifteen of 18 patients responded, 6 with a clinical complete response, 9 with a partial clinical response, and 3 nonresponders. Thirteen underwent mastectomy with 3 pathological complete responses. Tumor hypoxia was present in 8 of 13 patients (pO(2) = 4.7 +/- 1.2 mmHg). Five patients had well-oxygenated tumors (pO(2) = 27.6 +/- 7.8 mmHg). Patients with well-oxygenated tumors before treatment as well as those with significant reoxygenation had a favorable clinical response. Tumor reoxygenation appeared to be temperature dependent and associated with the lower thermal doses. CONCLUSIONS: This novel therapeutic program resulted in a high response rate in patients with LABC. Hyperthermia may offer a strategy for improving tumor reoxygenation with consequent treatment response. However, the effect of hyperthermia on tumor reoxygenation appears to depend on thermal dose and requires additional investigation. 相似文献
1000.
Omar I Abdel-Wahab Elizabeth Grubbs Benjamin L Viglianti Tsung-Yen Cheng Tomio Ueno SaeHee Ko Zahid Rabbani Simon Curtis Scott K Pruitt Mark W Dewhirst Doug S Tyler 《Clinical cancer research》2004,10(17):5919-5929
The role of hyperthermia during regional alkylating agent chemotherapy is controversial. The aim of this study was to determine the exact contribution of hyperthermia to tumor response during isolated limb infusion with l-phenylalanine mustard. Rats bearing rodent fibrosarcoma on the hindlimb underwent isolated limb infusion with saline, saline plus heat, l-phenylalanine mustard, l-phenylalanine mustard under conditions of normothermia, or l-phenylalanine mustard plus hyperthermia. Heat was administered locally using an in-line hot water circulation loop. Treatment with l-phenylalanine mustard at a concentration of 15 or 50 micrograms/mL was ineffective at producing tumor growth delay (P = 0.24 and 0.41, respectively). Furthermore, thermal enhancement of l-phenylalanine mustard activity was not seen at 15 micrograms/mL. However, administration of high-dose l-phenylalanine mustard, 50 micrograms/mL, with increasing amounts of heat yielded increasing tumor growth delay, increased regressions, and decreased proliferative index. Although l-phenylalanine mustard infusion under normothermia yielded a tumor growth delay of 7.1 days, combination l-phenylalanine mustard + hyperthermia treatment produced tumor growth delay of 27.0 days (P < 0.01; with two of five animals showing a complete response). Four hours after isolated limb infusion, 50.9% of cells in tumor treated with l-phenylalanine mustard + hyperthermia experienced apoptosis, whereas only 18.1, 16, and 4.4% of cells underwent apoptosis after treatment with l-phenylalanine mustard, saline + hyperthermia, or saline. The mean concentration of l-phenylalanine mustard within tumor relative to perfusate following isolated limb infusion was found to be similar among all groups at 0.023, 0.025, and 0.032 in animals undergoing isolated limb infusion with l-phenylalanine mustard, l-phenylalanine mustard + normothermia, and l-phenylalanine mustard + hyperthermia, respectively. These data indicate a synergistic cytotoxic effect of l-phenylalanine mustard + hyperthermia in isolated limb infusion, which is not attributable to enhanced tumor drug uptake. 相似文献