全文获取类型
收费全文 | 191336篇 |
免费 | 12835篇 |
国内免费 | 2235篇 |
专业分类
耳鼻咽喉 | 2548篇 |
儿科学 | 3575篇 |
妇产科学 | 4253篇 |
基础医学 | 28607篇 |
口腔科学 | 4263篇 |
临床医学 | 17848篇 |
内科学 | 36356篇 |
皮肤病学 | 4929篇 |
神经病学 | 14429篇 |
特种医学 | 9182篇 |
外国民族医学 | 2篇 |
外科学 | 25818篇 |
综合类 | 4542篇 |
现状与发展 | 5篇 |
一般理论 | 87篇 |
预防医学 | 11562篇 |
眼科学 | 4970篇 |
药学 | 16467篇 |
中国医学 | 1983篇 |
肿瘤学 | 14980篇 |
出版年
2023年 | 1080篇 |
2022年 | 2957篇 |
2021年 | 5214篇 |
2020年 | 2700篇 |
2019年 | 3948篇 |
2018年 | 5027篇 |
2017年 | 3744篇 |
2016年 | 4691篇 |
2015年 | 6218篇 |
2014年 | 7649篇 |
2013年 | 9320篇 |
2012年 | 13924篇 |
2011年 | 13567篇 |
2010年 | 8053篇 |
2009年 | 6751篇 |
2008年 | 10407篇 |
2007年 | 10388篇 |
2006年 | 9532篇 |
2005年 | 8944篇 |
2004年 | 7979篇 |
2003年 | 6968篇 |
2002年 | 6030篇 |
2001年 | 6598篇 |
2000年 | 6170篇 |
1999年 | 5028篇 |
1998年 | 1966篇 |
1997年 | 1431篇 |
1996年 | 1249篇 |
1995年 | 1131篇 |
1994年 | 987篇 |
1993年 | 854篇 |
1992年 | 2556篇 |
1991年 | 2437篇 |
1990年 | 2134篇 |
1989年 | 2106篇 |
1988年 | 1948篇 |
1987年 | 1761篇 |
1986年 | 1695篇 |
1985年 | 1483篇 |
1984年 | 1023篇 |
1983年 | 878篇 |
1982年 | 576篇 |
1981年 | 514篇 |
1980年 | 454篇 |
1979年 | 720篇 |
1978年 | 488篇 |
1977年 | 469篇 |
1976年 | 420篇 |
1974年 | 441篇 |
1973年 | 419篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Elizabeth S Hart Marilyn H Kelly Beth Brillante Clara C Chen Navid Ziran Janice S Lee Penelope Feuillan Arabella I Leet Harvey Kushner Pamela G Robey Michael T Collins 《Journal of bone and mineral research》2007,22(9):1468-1474
Most lesions in FD and their attendant functional disability occur within the first decade; 90% of lesions are present by 15 years, and the median age when assistive devices are needed is 7 years. These findings have implications for prognosis and determining the timing and type of therapy. INTRODUCTION: Fibrous dysplasia of bone (FD) is an uncommon skeletal disorder in which normal bone is replaced by abnormal fibro-osseous tissue. Variable amounts of skeletal involvement and disability occur. The age at which lesions are established, the pace at which the disease progresses, if (or when) the disease plateaus, and how these parameters relate to the onset of disability are unknown. To answer these questions, we performed a retrospective analysis of a group of subjects with FD. MATERIALS AND METHODS: One hundred nine subjects with a spectrum of FD were studied for up to 32 years. Disease progression was assessed in serial (99)Tc-MDP bone scans by determining the location and extent of FD lesions using a validated bone scan scoring tool. Physical function and the need for ambulatory aids were assessed. RESULTS: Ninety percent of the total body disease skeletal burden was established by age 15. Disease was established in a region-specific pattern; in the craniofacial region, 90% of the lesions were present by 3.4 yr, in the extremities, 90% were present by 13.7 yr, and in the axial skeleton, 90% were present by 15.5 yr. Twenty-five of 103 subjects eventually needed ambulatory aids. The median age at which assistance was needed was 7 yr (range, 1-43 yr). The median bone scan score for subjects needing assistance was 64.3 (range, 18.6-75) compared with 23.1 (range, 0.5-63.5) in the unassisted subjects (p < 0.0001). Among subjects needing assistance with ambulation, 92% showed this need by 17 yr. CONCLUSIONS: The majority of skeletal lesions and the associated functional disability occur within the first decade of life. The implication is that the window of time for preventative therapies is narrow. Likewise, therapeutic interventions must be tailored to where the patient is in the natural history of the disease (i.e., progressive disease [young] versus established disease [older subjects]). These findings have implications for prognosis, the timing and type of therapy, and the development of trials of new therapies and their interpretation. 相似文献
102.
Su Jin Park Su Jin Kim Yumie Rhee Ji Hyun Byun Seong Hwan Kim Myoung Hee Kim Eun Jig Lee Sung-Kil Lim 《Journal of bone and mineral research》2007,22(6):889-896
The FIGNL1 gene was proven to be a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). In this in vitro study, the AAA proteins inhibited osteoblast proliferation and stimulated osteoblast differentiation. We showed that FIGNL1 may play some regulatory role in osteoblastogenesis. INTRODUCTION: The fidgetin-like 1 (FIGNL1) gene encodes a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). Although the FIGNL1 protein localizes to both the nucleus and cytoplasm, the function of FIGNL1 remains unknown. In a previous study, we identified several genes that mediate the anabolic effects of basic fibroblast growth factor (bFGF) on bone by using microarray data. FIGNL1 was one of the genes that downregulated >2-fold in MC3T3-E1 cells after treatment with bFGF. Therefore, this study was aimed to identify and confirm the function of FIGNL1 on osteoblastogenesis. MATERIALS AND METHODS: We examined the effect of the FIGNL1 gene on proliferation, differentiation, and apoptosis in mouse osteoblast cells (MC3T3-E1 and mouse primary calvarial cells) using flow cytometry, RT-PCR, cell proliferation assay, and cell death assay. MC3T3-E1 cells and mouse calvarial cells were transfected with small interfering RNA (siRNA) directed against the FIGNL1 or nontargeting control siRNA and examined by cell proliferation and cell death assays. Also, FIGNL1 was fused to enhance green fluorescent protein (EGFP), and the EGFP-fused protein was transiently expressed in MC3T3-E1 cells. RESULTS: Reduced expression of FIGNL1 by bFGF and TGF-beta1 treatment was verified by RT-PCR analysis. Overexpression of FIGNL1 reduced the proliferation of MC3T3-E1 and calvarial cells, more than the mock transfected control cells did. In contrast, siFIGNL1 transfection significantly increased the proliferation of osteoblasts, whereas overexpression of FIGNL1 did not seem to alter apoptosis in osteoblasts. Meanwhile, overexpression of FIGNL1 enhanced the mRNA expression of alkaline phosphatase (ALP) and osteocalcin (OCN) in osteoblasts. In contrast, siFIGNL1 decreased the expression of ALP and OCN. A pEGFP-FIGNL1 transfected into MCT3-E1 cells had an initially ubiquitous distribution and rapidly translocated to the nucleus 1 h after bFGF treatment. CONCLUSIONS: From these results, we proposed that FIGNL1, a subfamily member of the AAA family of proteins, might play some regulatory role in osteoblast proliferation and differentiation. Further analyses of FIGNL1 will be needed to better delineate the mechanisms contributing to the inhibition of proliferation and stimulation of osteoblast differentiation. 相似文献
103.
W.-S. Ahn D.-J. Kim† G.-T. Chae‡ J.-M. Lee S.-M. Bae§ J.-I. Sin§ Y.-W. Kim§ S.-E. Namkoong & I. P. Lee 《International journal of gynecological cancer》2004,14(4):589-594
A mushroom extract, Agaricus blazei Murill Kyowa (ABMK), has been reported to possess antimutagenic and antitumor effects. Here, we investigate the beneficial effects of ABMK consumption on immunological status and qualities of life in cancer patients undergoing chemotherapy. One hundred cervical, ovarian, and endometrial cancer patients were treated either with carboplatin (300 mg / m(2)) plus VP16 (etoposide, 100 mg / m(2)) or with carboplatin (300 mg / m(2)) plus taxol (175 mg / m(2)) every 3 weeks for at least three cycles with or without oral consumption of ABMK. We observed that natural killer cell activity was significantly higher in ABMK-treated group (ANOVA, n = 39, P < 0.002) as compared with nontreated placebo group (n = 61). However, no significant difference in lymphokine-activated killer and monocyte activities was observed in a manner similar to the count of specific immune cell populations between ABMK-treated and nontreated groups. However, chemotherapy-associated side effects such as appetite, alopecia, emotional stability, and general weakness were all improved by ABMK treatment. Taken together, this suggests that ABMK treatment might be beneficial for gynecological cancer patients undergoing chemotherapy. 相似文献
104.
105.
106.
J C Shih T L Ko M C Lin M K Shyu C N Lee F J Hsieh 《Ultrasound in obstetrics & gynecology》2004,24(2):202-206
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma. 相似文献
107.
108.
109.
110.
Seong-Beom Koh Byung-Jo Kim Moon Ho Park Sung-Wook Yu Kun-Woo Park Dae Hie Lee 《Journal of clinical neuroscience》2007,14(11):1073-1077
Cerebral infarction as a complication of tubercular (TB) meningitis is not uncommon, but an adequate comparison of patients with and without stroke has not been carried out. This study was performed to evaluate the clinical characteristics of cerebral infarction secondary to TB meningitis, and to investigate predictive factors for cerebral infarction in patients with TB meningitis. Patients with TB meningitis were recruited over a period of 56 months. They were divided into two groups, those with and those without stroke. Demographic features and clinical, laboratory, and neuroradiological findings were compared between the two groups. We classified strokes into subtypes using neuroimaging findings. Of the 38 patients who were diagnosed with TB meningitis, eight also experienced cerebral infarction. The percentage of cerebrospinal fluid leukocytes that were neutrophils was significantly higher in patients with stroke (68%) than in patients without stroke (31%; p=0.0001). Upon initial CT imaging, meningeal enhancement was found in 11 patients, and of these patients, six experienced stroke. There were no significant differences between the groups with respect to other clinical and laboratory features, including demographic features, time between meningitis onset and treatment initiation, peripheral white blood cell count, and cerebrospinal fluid findings. Five of the eight patients who developed stroke had lacunar infarcts. One of the three patients with territorial nonlacunar infarction died due to herniation. When treating patients with TB meningitis, the possibility of cerebral infarction should be considered when patients develop focal neurological signs, meningeal enhancement on a CT scan, and sustained polymorphic cerebrospinal fluid pleocytosis. 相似文献