全文获取类型
收费全文 | 1464篇 |
免费 | 92篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 37篇 |
妇产科学 | 26篇 |
基础医学 | 167篇 |
口腔科学 | 35篇 |
临床医学 | 117篇 |
内科学 | 414篇 |
皮肤病学 | 12篇 |
神经病学 | 98篇 |
特种医学 | 26篇 |
外科学 | 237篇 |
综合类 | 10篇 |
预防医学 | 58篇 |
眼科学 | 30篇 |
药学 | 103篇 |
中国医学 | 2篇 |
肿瘤学 | 160篇 |
出版年
2023年 | 11篇 |
2022年 | 20篇 |
2021年 | 35篇 |
2020年 | 21篇 |
2019年 | 29篇 |
2018年 | 38篇 |
2017年 | 20篇 |
2016年 | 26篇 |
2015年 | 48篇 |
2014年 | 56篇 |
2013年 | 69篇 |
2012年 | 103篇 |
2011年 | 101篇 |
2010年 | 67篇 |
2009年 | 60篇 |
2008年 | 82篇 |
2007年 | 90篇 |
2006年 | 91篇 |
2005年 | 71篇 |
2004年 | 68篇 |
2003年 | 90篇 |
2002年 | 80篇 |
2001年 | 36篇 |
2000年 | 26篇 |
1999年 | 28篇 |
1998年 | 18篇 |
1997年 | 14篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 9篇 |
1992年 | 19篇 |
1991年 | 12篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 9篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 5篇 |
1977年 | 5篇 |
1974年 | 5篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1967年 | 5篇 |
1966年 | 5篇 |
排序方式: 共有1568条查询结果,搜索用时 0 毫秒
61.
Anette Östlund Gunnel Hensing Annika Jakobsson Valter Sundh Fredrik Spak 《Substance abuse treatment, prevention, and policy》2007,2(1):24-9
Background
A better understanding of the relationship between treatment-seeking for alcohol problems and personality traits could give useful insight in factors promoting or hindering treatment for alcohol use disorders (AUD). The aim of this study was to analyze the associations between treatment-seeking for AUD, personality traits, and psychiatric co-morbidity in women. The study was based on pooled cross-sectional data from three population based samples and one clinical sample (n = 1,339). Comparisons were made between treated and untreated women with AUD, and between those with resolved and unresolved AUD. 相似文献62.
A Ghidini M Sirtori P Vergani S Mariani E Tucci G C Scola 《American journal of obstetrics and gynecology》1989,160(1):86-87
In utero sonographic visualization of fetal intracranial calcifications during the second trimester is reported. Its diagnostic process, which included percutaneous umbilical cord blood sampling and fetal paracentesis, is described. 相似文献
63.
Twenty-seven consecutive patients with adolescent idiopathic scoliosis underwent posterior spinal fusion with pediatric Texas Scottish Rite Hospital instrumentation. Coralline hydroxyapatite (Interpore, Irvine, Calif) was mixed with limited autograft from posterior iliac crest (an approximate 70/30 ratio of coralline hydroxyapatite to autograft). Patient evaluation was based on clinical and radiographic findings. On initial radiographic evaluation, a "snowstorm" appearance consistent with the exoskeleton of the coralline hydroxyapatite was observed. After two years, the fusion mass had a "marble-like" appearance with distinct decreased visibility of the disk spaces in the fusion mass. This latter stage of "marbilization correlated with solid fusion clinically. All patients achieved solid fusion at an average follow-up of 27 months. Coralline hydroxyapatite is safe, biocompatible, and effective in augmenting autogenous bone graft in the treatment of idiopathic adolescent scoliosis with posterior spinal fusion. In addition to decreased donor site morbidity, this may be invaluable in cases where there is insufficient autograft available. 相似文献
64.
Ischemia-induced reperfusion injury seems to play an important role in the pathophysiology of "idiopathic" carpal tunnel syndrome (CTS). The common final pathway in this developmental sequence is thought to be an intermittent increase in interstitial pressure, leading to degenerative changes in the flexor tenosynovium and fibrotic changes in the perineural tissue. We hypothesize that this concurrently leads to alteration in the physical properties of the synovium, leading to its rapid and persistent swelling. A prospective study was conducted on synovial tissue obtained from 27 CTS patients. The in vitro synovial absorption rate of CTS patients was significantly higher in the first hour compared to controls (n = 7). This difference was maintained up to 5-6 h, albeit at a slower rate. Rapid absorption and retention of fluid by the synovium led to increased interstitial pressure and nerve compression, resulting in early and persistent manifestation of symptoms in sensitized patients. 相似文献
65.
Miglior S Zeyen T Pfeiffer N Cunha-Vaz J Torri V Adamsons I;European Glaucoma Prevention Study Group 《Ophthalmology》2002,109(9):1612-1621
OBJECTIVES: The European Glaucoma Prevention Study seeks to evaluate the efficacy of reducing intraocular pressure (IOP), with dorzolamide to prevent or delay patients affected by ocular hypertension from developing primary open-angle glaucoma. DESIGN: Randomized, double-blinded, controlled clinical trial. PARTICIPANTS: Patients (age > or =30 years) were enrolled from 18 European centers. The patients fulfilled a series of inclusion criteria including the measurements of IOP (22-29 mmHg), two normal and reliable visual fields (VFs) (on the basis of mean defect and corrected pattern standard deviation/corrected loss of variance of standard 30/II Humphrey or Octopus perimetry), and normal optic disc as determined by the Optic Disc Reading Center (vertical and horizontal cup-to-disc ratios; asymmetry between the two eyes < or =0.4). INTERVENTION: Patients were randomized to the treatment with dorzolamide or a placebo. MAIN OUTCOME MEASURES: End points are VF and/or optic disc changes. A VF change during the follow-up must be confirmed by two further positive tests. Optic disc change is defined by the agreement of two out of three independent observers evaluating optic disc stereo-slides. RESULTS: One thousand seventy-seven subjects were randomized between January 1, 1997 and May 31, 1999. The mean age was 57.03 +/- 10.3 years; 54.41% were women and 99.9% were Caucasian. Mean IOP was 23.6 +/- 1.6 mmHg in both eyes. Mean visual acuity was 0.97 +/- 0.11 in both eyes; mean refraction was 0.23 +/- 1.76 diopters in the right eye and 0.18 +/- 1.79 diopters in the left eye. Previous use of medication for ocular hypertension was reported by 38.4% of the patients, systemic hypertension by 28.1%, cardiovascular diseases by 12.9%, and diabetes mellitus by 4.7%. The qualifying VFs were normal and reliable according to protocol criteria. CONCLUSIONS: The mean IOP of the patients enrolled in the European Glaucoma Prevention Study is consistent with the estimated mean IOP (within the range of 22-29 mmHg) found in a large sample of the European population. The European Glaucoma Prevention Study should be able to better address the clinical question of whether pharmacological reduction of IOP (by means of dorzolamide) in ocular hypertension patients at moderate risk for developing primary open-angle glaucoma effectively lowers the incidence of primary open-angle glaucoma. 相似文献
66.
Nicotinic--serotonergic interactions in brain and behaviour 总被引:5,自引:0,他引:5
This review focuses on nicotinic--serotonergic interactions in the central nervous system (CNS). Nicotine increases 5-hydroxytryptamine (5-HT) release in the cortex, striatum, hippocampus, dorsal raphé nucleus (DRN), hypothalamus, and spinal cord. As yet, there is little firm evidence for nicotinic receptors on serotonergic terminals and thus nicotine's effects on 5-HT may not necessarily be directly mediated, but there is strong evidence that the 5-HT tone plays a permissive role in nicotine's effects. The effects in the cortex, hippocampus, and DRN involve stimulation of 5-HT(1A) receptors, and in the striatum, 5-HT(3) receptors. The 5-HT(1A) receptors in the DRN play a role in mediating the anxiolytic effects of nicotine and the 5-HT(1A) receptors in the dorsal hippocampus and lateral septum mediate its anxiogenic effects. The increased startle and anxiety during nicotine withdrawal is mediated by 5-HT(1A) and 5-HT(3) receptors. The locomotor stimulant effect of acute nicotine is mediated by 5-HT(1A) receptors and 5-HT(2) receptors may play a role in the expression of a sensitised response after chronic nicotine treatment. Unfortunately, the role of 5-HT(1A) receptors in mediating nicotine seeking has not yet been investigated and would seem an important area for future research. There is also evidence for nicotinic--serotonergic interactions in the acquisition of the water maze, passive avoidance, and impulsivity in the five-choice serial reaction task. 相似文献
67.
Upregulation of osteoblast apoptosis by malignant plasma cells: a role in myeloma bone disease 总被引:6,自引:0,他引:6
Silvestris F Cafforio P Tucci M Grinello D Dammacco F 《British journal of haematology》2003,122(1):39-52
Typical features of multiple myeloma (MM) are osteolytic lesions and severely affected bone regeneration. This study of 53 MM patients demonstrates an enhancement of osteoblast cytotoxicity by malignant myeloma cells via the upregulation of apoptogenic receptors, including Fas ligand (Fas-L) and tumour-necrosis-factor-related apoptosis inducing ligand (TRAIL). Both were significantly increased in the marrow myeloma cells of patients with extensive osteolytic lesions in a fashion similar to the highly malignant human myeloma cell line MCC-2. Osteoblasts from these subjects over-expressed Fas and death receptor (DR) 4/5 and underwent dramatic apoptosis when co-cultured with either MCC-2 or autologous myeloma cells. In osteoblast and myeloma cell co-cultures, monocyte chemoattractant protein 1 (MCP-1) mRNA was upregulated in osteoblasts from patients with severe bone disease in parallel with increased CC-chemokine receptor R2 (CCR2) expression, the ligand of MCP-1, in the myeloma cells. This chemokine was shown to activate malignant cell migration in vitro. An upregulation of ICAM-1 expression occurred in osteoblasts from patients with active skeleton disease. This upregulation appeared to be an effect of malignant plasma cell contact, as MCC-2 co-culture greatly enhanced ICAM-1 production by resting osteoblasts from patients without skeleton involvement. Our results suggest that osteoblasts in active myeloma are functionally exhausted and promptly undergo apoptosis in the presence of myeloma cells from patients with severe bone disease. It is suggested that this cytotoxic effect plays a pivotal role in the pathogenesis of defective bone repair. 相似文献
68.
69.
Genn RF Tucci SA Thomas A Edwards JE File SE 《Neuroscience and biobehavioral reviews》2003,27(1-2):155-161
The effects of mild food deprivation (7 days of food restricted to once daily feeding to maintain body weights at 85% of free-feeding weights) were examined in adult male and female and adolescent female rats tested in the elevated plus maze and social interaction tests of anxiety. In adult male rats, food deprivation appeared to have an anxiolytic effect in the plus-maze as it significantly increased the percentage of entries onto open arms and the percentage of time spent on the open arms, without changing the number of closed arm entries. There were no effects of food deprivation in adult females, although in adolescent females food deprivation significantly increased the percentage of open arm entries rats. Adolescent female rats have female brains, but do not have circulating gonadal hormones and thus these results suggest that circulating female gonadal hormones are able to suppress some of the effects of mild food deprivation in the plus-maze. In the social interaction test, there were no effects of food deprivation in any group on the time spent in social interaction. There were opposite effects on locomotor activity in the adult male and female rats, with deprivation increasing activity in males and decreasing it in females. There were no effects of food deprivation on locomotor activity in the adolescent females, suggesting that circulating gonadal hormones were responsible for the bidirectional effects in the adult rats. In both tests there were age-associated differences in the female rats, with the adolescent females being less anxious (higher percentage of open arm entries and increased social interaction) than the adults. 相似文献
70.
Casati V Sandrelli L Speziali G Calori G Grasso MA Spagnolo S 《The Journal of thoracic and cardiovascular surgery》2002,123(6):1084-1091
OBJECTIVE: We studied the hemostatic effects of tranexamic acid in patients undergoing elective surgery involving the thoracic aorta. METHODS: In a double-blind, randomized fashion, 60 consecutive patients were assigned to two treatment groups: 30 patients (placebo group) received infusion of saline solution, and 30 (treatment group) received tranexamic acid (1 g before skin incision, an infusion of 400 mg/h during the operation, and 500 mg in the pump priming). Perioperative bleeding was considered as a primary outcome. Perioperative allogeneic transfusions, major thrombotic complications (myocardial infarction, pulmonary embolism, renal insufficiency), and surgical outcomes were also considered. RESULTS: Patients treated with tranexamic acid showed significant reductions in postoperative bleeding, both in terms of the amount collected during the first 4 postoperative hours (median 307 mL, interquartile range 253-361 mL in the placebo group vs median 211 mL, interquartile range 108-252 mL in the treatment group, P =.002) and in terms of total bleeding (median 722 mL, interquartile range 574-952 mL in the placebo group vs median 411 mL, interquartile range 313-804 mL in the treatment group, P =.04). Consequently, the number of patients transfused differed significantly between groups (21 patients [72.4%] in the placebo group vs 13 [44.8%] in the treatment group, P =.033). Patients in the treatment group showed significant reductions in the total amount for the entire group of packed red cells transfused (13,500 mL in the treatment group vs 28,000 mL in the placebo group, P =.012) and in the total amount of allogeneic transfusions (23,400 mL in the treatment group vs 53,000 mL in the placebo group, P =.024). No differences in perioperative thrombotic complications were found. CONCLUSIONS: In this initial series of patients undergoing thoracic aortic surgery, tranexamic acid appeared effective in reducing perioperative bleeding, with a significant reduction in the need for allogeneic transfusions and without any increased risk of thrombotic complications. 相似文献