全文获取类型
收费全文 | 17510篇 |
免费 | 1218篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 186篇 |
儿科学 | 395篇 |
妇产科学 | 291篇 |
基础医学 | 2375篇 |
口腔科学 | 354篇 |
临床医学 | 1360篇 |
内科学 | 4243篇 |
皮肤病学 | 535篇 |
神经病学 | 1348篇 |
特种医学 | 690篇 |
外科学 | 3172篇 |
综合类 | 286篇 |
一般理论 | 15篇 |
预防医学 | 1040篇 |
眼科学 | 480篇 |
药学 | 779篇 |
中国医学 | 43篇 |
肿瘤学 | 1218篇 |
出版年
2023年 | 89篇 |
2022年 | 206篇 |
2021年 | 397篇 |
2020年 | 239篇 |
2019年 | 353篇 |
2018年 | 387篇 |
2017年 | 315篇 |
2016年 | 383篇 |
2015年 | 418篇 |
2014年 | 600篇 |
2013年 | 758篇 |
2012年 | 1155篇 |
2011年 | 1122篇 |
2010年 | 678篇 |
2009年 | 599篇 |
2008年 | 1025篇 |
2007年 | 1056篇 |
2006年 | 1007篇 |
2005年 | 1068篇 |
2004年 | 994篇 |
2003年 | 871篇 |
2002年 | 895篇 |
2001年 | 314篇 |
2000年 | 292篇 |
1999年 | 258篇 |
1998年 | 180篇 |
1997年 | 156篇 |
1996年 | 136篇 |
1995年 | 138篇 |
1994年 | 127篇 |
1993年 | 92篇 |
1992年 | 120篇 |
1991年 | 137篇 |
1990年 | 114篇 |
1989年 | 129篇 |
1988年 | 145篇 |
1987年 | 113篇 |
1986年 | 110篇 |
1985年 | 92篇 |
1984年 | 94篇 |
1983年 | 114篇 |
1982年 | 135篇 |
1981年 | 114篇 |
1980年 | 93篇 |
1979年 | 67篇 |
1978年 | 68篇 |
1977年 | 75篇 |
1976年 | 49篇 |
1975年 | 42篇 |
1974年 | 50篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
21.
Jonas T. Johnson David G. Mayernik Eugene N. Myers Teresa A. Nolan Victor L. Schramm Barbara S. Sigler Robin L. Wagner 《Head & neck》1987,9(6):336-340
Patients with locally advanced, inoperable squamous cell carcinoma of the head and neck were offered three courses of cisplatin and 96-h 5-fluorouracil (5-FU) infusion. Subsequent therapy included surgery when feasible, irradiation therapy, and a maintenance program of methotrexate (MTX)-5-FU. Thirty-three patients were evaluated prospectively. Seven patients underwent a single course of chemotherapy. Five patients underwent two courses of chemotherapy. Twenty-one patients underwent three courses of adjuvant chemotherapy. The overall response rate was 48% (16 of 33). Fifteen of 21 patients (76%) receiving three courses of chemotherapy evidenced a response; this included three complete responses (CRs) (9%). No responses were seen in patients receiving only one or two courses of chemotherapy. Among responding patients, the initial favorable response to chemotherapy was apparent after the first course of chemotherapy. Patients who failed to demonstrate any response after two courses of chemotherapy did not respond after a third course. A significant group of patients fail to respond and should be offered participation in other investigational protocols as they become available. 相似文献
22.
V Ahern E‐S Koh V Gebski Y Sathiyaseelan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):458-464
The purpose of this study was to document how children in Australia with medulloblastoma are being treated and to evaluate the quality of radiotherapy (RT) delivered. The Radiotherapy Database of the Australian and New Zealand Children’s Haematology and Oncology Group was used to identify 46 children with medulloblastoma younger than the age of 15 years treated with radical intent by craniospinal irradiation between 1997 and 1999 inclusively. Twenty‐six patients had completely resected disease without evidence of disease spread. Of these, 16 patients received a craniospinal RT dose of <25 Gy in addition to chemotherapy. RT treatment immobilization methods varied, as did planning methods. RT dose to critical structures was recorded on treatment plans for only 15% of patients. The average systematic error in shield placement at the posterior orbit was 5.2 mm, and two‐thirds of patients were ‘overshielded’ at this site. Adequate coverage of the distal end of the thecal sac was achieved in fewer than 50% of on‐treatment verification films for 21 of 45 patients. With a reduction in RT dose to the craniospinal axis for paediatric medulloblastoma, greater attention is needed for patient immobilization, documentation of RT dose to critical structures and the placement and reproducibility of shielding. 相似文献
23.
Retinopathy of prematurity (ROP) is a vaso-proliferative disease with infiltration of the vitreous gel. Contraction of the infiltrate results in traction detachment with typical peripheral trough formation. Cryotherapy inhibits proliferation in the active stages of the disease (Stage 3, 'plus'). With development of traction detachment involving the macula (Stage 48) encircling buckling procedures should first be tried. Closed vitrectomy is considered when high retinal detachment and opacification by vitreous strands occur. The surgical technique is described. Anatomical (64%) and functional (43%) successes are reasonably high for Stage 4 cases, but disappointing (anatomical 40%, functional 16%) for Stage 5 ROP. Open funnels of detached retina fare better than closed ones. It is probably best to perform surgery not before the cicatricial stage, i.e. six months after birth. 相似文献
24.
Anne T. Berg Shlomo Shinnar‡§ Eugene D. Shapiro Morton E. Salomon‡ Ellen F. Crain‡ W. Allen Hauser§ 《Epilepsia》1995,36(4):334-341
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures. 相似文献
25.
M Nakamura E Koh N Kondoh M Takeyama M Namiki H Fujioka H Kiyohara Y Nishimune A Okuyama T Sonoda 《Archives of andrology》1990,24(1):69-72
The synthesis of DNA, RNA, and protein by varicocele testes with spermatogenic dysfunction was studied by examination of the levels of incorporation of [3H]thymidine, [14C]uridine, and [14C]leucine into the testicular tissue at 31 degrees C in vitro. The results suggest that DNA synthesis by the testis with moderate tubular damage is impaired whereas synthesis of RNA and protein is not. The cell regenerative ability of the testis with moderate tubular damage may be poor in spite of the preservation of testicular cell RNA and protein synthesis. 相似文献
26.
The present study provides an analysis of the effects of particular patterns of teacher respose to students' entries in dialogue journals. It extended on previous research related to teacher-student instructional discourse by concentrating on written, teacher-student interactions. Second grade children who were participating in a daily dialogue journal activity were randomly subjected to two types of response patterns by their teacher. The results show that a teacher's elaborative responses to student journal entries directly lead to increase written output by students coupled with a distinct process #ophigher order#cp orientation of student entries. 相似文献
27.
28.
29.
Johannes Bjornsson John R. Goellner David Eugene Williams Mary V. Scheiber 《Journal of cancer research and clinical oncology》1986,111(3):289-290
Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones. 相似文献
30.
Tzu G Wu William A Rose Thomas B Albrecht Eugene P Knutson Rolf K?nig Joana R Perdig?o Alexandra P A Nguyen W Robert Fleischmann 《Journal of interferon & cytokine research》2007,27(1):13-22
Long-term treatment of mouse cancer cells with interferon-alpha (IFN-alpha) converts parental B16 melanoma cells to B16alpha vaccine cells. Inoculation of syngeneic mice with B16alpha vaccine cells triggers immunity to the parental B16 tumor that is mediated by host macrophages, T cells, and natural killer (NK) cells. Lymph node cells from mice inoculated with irradiated B16alpha vaccine cells, but not with irradiated parental cells, proliferate when cultured in vitro, suggesting long-term in vivo activation of lymphoid cells. Long-term IFN-alpha treatment of B16alpha vaccine cells induced both interleukin-15 (IL-15) mRNA and IL-15 protein. The bulk of the induced IL-15 remained cell associated, either cytoplasmic or associated with the cell membrane. Immunofluorescence microscopy studies showed that the cell-associated IL-15 was broadly distributed throughout the cytoplasm. These observations suggest that long-term IFN-alpha treatment may induce primarily the truncated isoform of IL-15. Vaccination with irradiated B16alpha vaccine cells may promote tumor immunity by releasing high levels of cell-associated IL-15 when spontaneously lysed or directly killed by innate immune cells. The release of accumulated cell-associated IL-15 may then trigger a host T cell response to tumor antigens and cause host development of immunity to the B16 tumor cells. 相似文献