全文获取类型
收费全文 | 7565篇 |
免费 | 468篇 |
国内免费 | 144篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 234篇 |
妇产科学 | 156篇 |
基础医学 | 914篇 |
口腔科学 | 165篇 |
临床医学 | 622篇 |
内科学 | 2000篇 |
皮肤病学 | 153篇 |
神经病学 | 777篇 |
特种医学 | 234篇 |
外科学 | 1134篇 |
综合类 | 59篇 |
预防医学 | 335篇 |
眼科学 | 88篇 |
药学 | 434篇 |
中国医学 | 10篇 |
肿瘤学 | 784篇 |
出版年
2023年 | 62篇 |
2022年 | 94篇 |
2021年 | 213篇 |
2020年 | 105篇 |
2019年 | 160篇 |
2018年 | 172篇 |
2017年 | 141篇 |
2016年 | 186篇 |
2015年 | 175篇 |
2014年 | 218篇 |
2013年 | 299篇 |
2012年 | 409篇 |
2011年 | 391篇 |
2010年 | 260篇 |
2009年 | 222篇 |
2008年 | 364篇 |
2007年 | 452篇 |
2006年 | 400篇 |
2005年 | 388篇 |
2004年 | 358篇 |
2003年 | 295篇 |
2002年 | 277篇 |
2001年 | 243篇 |
2000年 | 268篇 |
1999年 | 195篇 |
1998年 | 112篇 |
1997年 | 103篇 |
1996年 | 112篇 |
1995年 | 71篇 |
1994年 | 70篇 |
1993年 | 49篇 |
1992年 | 138篇 |
1991年 | 119篇 |
1990年 | 112篇 |
1989年 | 105篇 |
1988年 | 96篇 |
1987年 | 94篇 |
1986年 | 80篇 |
1985年 | 70篇 |
1984年 | 81篇 |
1983年 | 47篇 |
1982年 | 35篇 |
1981年 | 32篇 |
1980年 | 27篇 |
1979年 | 42篇 |
1978年 | 29篇 |
1977年 | 18篇 |
1976年 | 35篇 |
1974年 | 18篇 |
1973年 | 17篇 |
排序方式: 共有8177条查询结果,搜索用时 15 毫秒
101.
Russo P Persegani C Papeschi LL Nicolini M Trimarchi M 《The International journal of neuroscience》1999,100(1-4):29-37
The present study examined sex differences in hemisphere preference (HP) assessed by the Preference Test (PT). This instrument is designed to measure the extent to which normal subjects rely on right-hemisphere or left-hemisphere cognition. Factor analysis on the total sample (N=1,057; 473 men and 584 women) revealed a clear two-factor structure (i.e., left-HP and right-HP), although separate analyses for men and women suggest that this structure is more straightforward in men than in women. The main differences between men and women have to do with PT items relevant to language abilities, where women tend to be more symmetrically distributed across the two factors. However, the frequency of right- and left-HP is similar in men and women and does not change for men when PT scores are recalculated after removal of unspecific items. Furthermore, once the items that assess verbal abilities were excluded, the corrected PT value for women showed higher right-HP. Our results provide some indications of a less pronounced lateralization of hemisphere-linked cognitive abilities in women. 相似文献
102.
Although human glioblastoma cell line A172 presents tumor necrosis factor (TNF) high affinity receptors, it is resistant to TNF-mediated cytotoxicity. Preincubation of cells with 10 ng/ml interferon (IFN)-gamma for 6 h causes a great increase in TNF receptor numbers (about 477%). IFN-gamma alone is not cytotoxic in A172 cells. Cells preincubated with 10 ng/ml IFN-gamma for 6 h became more sensitive to the TNF cytotoxicity (about 400%). In A172 cells the enhanced TNF receptor expression may contribute to the enhancement of TNF cytotoxicity. This observation may have importance in designing new more effective therapies for human gliomas. 相似文献
103.
High-dose chemotherapy and autologous bone marrow rescue for patients with refractory germ cell tumors. Early intervention is better tolerated. 总被引:1,自引:0,他引:1
R J Motzer S C Gulati J P Crown S Weisen M Doherty H Herr W Fair J Sheinfeld P Sogani P Russo 《Cancer》1992,69(2):550-556
Therapy with high-dose carboplatin plus etoposide-based chemotherapy plus autologous bone marrow rescue (AUBMR) was administered to 29 patients with advanced germ cell tumors (GCT) refractory to cisplatin-based chemotherapy. Two groups of patients with refractory disease were treated. Sixteen patients had been identified as "poor risk" at diagnosis and had an inappropriately slow decline of serum tumor markers after two cycles of induction cisplatin-based therapy (Group A). In addition, 13 patients were treated who had never had a complete response (CR) or had relapses after ifosfamide-based salvage chemotherapy (Group B). Patients in Group A were treated with high-dose carboplatin etoposide, and patients in Group B received high-dose carboplatin, etoposide, and cyclophosphamide. Fifteen of 29 (52%) patients had a CR (9, Group A; 6, Group B). The patients in Group A had fewer hematologic toxic effects, and the median number of days from day 0 to a granulocyte count greater than 0.5/microliters was 16 and to a platelet count of more than 50/microliters was 15, compared with 22 days and 23 days in Group B, respectively. There were fewer episodes of culture-positive sepsis in Group A (12%) compared with Group B (26%), and the only treatment-related death occurred in Group B. Therapy with high-dose carboplatin plus etoposide-based chemotherapy plus AUBMR is effective for patients with GCT refractory to regimens of cisplatin with or without ifosfamide. Early use of high-dose chemotherapy reduces hematologic toxic effects and allows patients to start treatment in a more predictable fashion after cytoreduction, rather than when the disease is progressing rapidly. 相似文献
104.
M. Strolin Benedetti A. Russo P. Marrari P. Dostert 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(3):191-203
Summary Concentrations of the sulfur-containing amino acids methionine, homocysteic acid, cysteic acid and taurine were measured in brain structures of young and old Wistar rats in an attempt to etablish a possible link between the increase in oxidative stress with ageing and changes in tissue levels of these amino acids. Contrary to data reported by others, in all brain structures of young and old rats homocysteic acid levels could not be quantified. Compared with young rats, in old animals taurine and methionine concentrations significantly decreased in striatum and cortex; decreased taurine levels were also found in nucleus accumbens and cerebellum and lower concentrations of methionine were found in midbrain, hippocampus and pons-medulla. Cysteic acid levels either did not change or significantly increased in cortex and hippocampus. These results are discussed taking into account the biosynthesis of sulfur-containing amino acids in rat brain and the decrease in glutathione in relation to oxidative stress with ageing.Changes in aspartic acid, glutamic acid, serine, glutamine, glycine and GABA concentrations with ageing were also determined in the same brain structures and were in good agreement with those previously reportedAbbreviations
H
2O2
hydrogen peroxide
-
MAO
monoamine oxidase
-
GSHP
glutathione peroxidase
-
PAPS
3-phosphoadenosine-5-phosphosulfate
-
OPA
O-phthaldialdehyde
-
HPLC
high performance liquid chromatography
-
Asp
aspartic acid
-
CA
cysteic acid
-
CSA
cysteine sulfinic acid
-
Cys
cysteine
-
GABA
-aminobutyric acid
-
Gln
glutamine
-
Glu
glutamic acid
-
Gly
glycine
-
HCA
homocysteic acid
-
Met
methionine
-
Ser
serine
-
Tau
taurine 相似文献
105.
B Memoli C Libetta M Sabbatini G Conte D Russo U Giani D Capone V E Andreucci 《Kidney international》1991,40(6):1134-1140
The aim of this study was the evaluation, in healthy subjects, of the renal functional reserve (RFR), that is, the GFR increase induced by a combined infusion of amino acids (AA) and dopamine (D), in conditions of extracellular volume depletion caused by diuretic administration. In particular, this study was undertaken: a) to evaluate whether and to which extent, AA + D can reverse the functional GFR impairment induced by salt depletion, without volume restoration; b) to study whether any relationship may be found between the GFR in normal condition (the so-called "resting" GFR), and/or the renal functional reserve and the GFR impairment induced by salt depletion, in order to understand the role of both "resting" GFR and RFR in the degree of renal dysfunction induced by salt depletion. In control conditions the i.v. infusion of AA + D significantly increased RPF (+ 41% vs. baseline period) with a mean absolute increase of 211 ml/min. A similar pattern was observed in GFR behavior (+31.5% with 34 ml/min of mean absolute increase). A significant inverse exponential relationship was observed between GFR before AA + D i.v. infusion ("resting" GFR) and renal functional reserve (P less than 0.05), suggesting that, in normal conditions, these inversely related parameters may widely vary according to the tone of the glomerular arterioles. Following salt depletion, we observed a variable degree of GFR impairment. Both GFR and RPF were significantly decreased (-25.9%, P less than 0.05 and -29%, P less than 0.05, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
106.
107.
108.
Russo RM 《Urban health》1982,11(6):45-48
Poverty has a major impact on the nation's state of health. Although its effects are difficult to separate from that of old age and the problems of minorities, there are definite correlations between indicators of economic well being and mortality/morbidity rates United States vital statistics and extensive health interview surveys provide ample documentation of the role of poverty as a health determinant. The success the Indian Health Service has had in lowering mortality rates mirrors the nation's as a whole and demonstrates what can be done if socioeconomic conditions, as well as health care delivery, is improved. The message should not be lost sight of it this era of cutbacks in social programs. 相似文献
109.
Abnormal visual event-related potentials in obsessive-compulsive disorder without panic disorder or depression comorbidity 总被引:4,自引:0,他引:4
Visual event-related potentials and spline map topography during a discriminative response task (DRT) were studied in 8 obsessive-compulsive disorder (OCD) patients without comorbidity for panic disorder or depression and in 12 age-matched controls. In the DRT task (like in a go/no-go task) the subject had to press a button when the target stimuli appeared and had to retain the response when the non-target stimulus appeared (vertical bars were intermixed with an equal probability of horizontals). OC patients had greater N1 latency than controls and their N1 and P3 amplitude was larger for the target stimuli, but not for non-target stimuli. In the normals, non-target stimuli (no-go task) produced a larger activation than target stimuli (go task). In the OCD patients the target stimuli produced the same large activation as the non-target. These findings are consistent with theories that consider OCD to be an attentional disorder deriving from a misallocating of cognitive resources. Moreover, spline map topography confirmed that P3 hyperactivation is localised principally on the frontal lobes. 相似文献
110.