全文获取类型
收费全文 | 1081篇 |
免费 | 61篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 62篇 |
妇产科学 | 25篇 |
基础医学 | 158篇 |
口腔科学 | 20篇 |
临床医学 | 46篇 |
内科学 | 221篇 |
皮肤病学 | 6篇 |
神经病学 | 93篇 |
特种医学 | 10篇 |
外科学 | 148篇 |
综合类 | 15篇 |
预防医学 | 185篇 |
眼科学 | 7篇 |
药学 | 69篇 |
中国医学 | 1篇 |
肿瘤学 | 73篇 |
出版年
2023年 | 7篇 |
2022年 | 9篇 |
2021年 | 34篇 |
2020年 | 15篇 |
2019年 | 33篇 |
2018年 | 38篇 |
2017年 | 23篇 |
2016年 | 17篇 |
2015年 | 23篇 |
2014年 | 35篇 |
2013年 | 47篇 |
2012年 | 55篇 |
2011年 | 66篇 |
2010年 | 42篇 |
2009年 | 30篇 |
2008年 | 63篇 |
2007年 | 58篇 |
2006年 | 63篇 |
2005年 | 77篇 |
2004年 | 55篇 |
2003年 | 53篇 |
2002年 | 34篇 |
2001年 | 26篇 |
2000年 | 31篇 |
1999年 | 23篇 |
1998年 | 9篇 |
1997年 | 8篇 |
1996年 | 8篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 13篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 14篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1970年 | 6篇 |
1969年 | 5篇 |
1968年 | 8篇 |
1967年 | 3篇 |
1966年 | 4篇 |
排序方式: 共有1143条查询结果,搜索用时 31 毫秒
1.
Roberto Rivera-Luna Marta Zapata-Tarrés Aurora Medina-Sansón Enrique López-Aguilar Ana Niembro-Zúñiga J. Amador Zarco Alfonso Marhx-Bracho Fernando Rueda-Franco Leticia Bornstein-Quevedo 《Child's nervous system》2007,23(5):543-547
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of
age diagnosed with low-grade astrocytoma.
Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three
patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection
and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy.
Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial
group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008).
Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the
outcome. 相似文献
2.
3.
Bagher Larijani Mir Reza Bekheirnia Akbar Soltani Alireza Khalili‐Far Hossein Adibi Reza Baradar Jalili 《American journal of human biology》2004,16(2):168-171
The aim of this study was to determine the relationships between bone mineral density (BMD) and blood pressure in 214 men, age 20–76. BMD measurements were done by dual X‐ray absorptiometry using a Lunar DPXMD densitometer at the lumbar spine (L2–L4) and different femoral regions. Systolic (SBP) and diastolic (DBP) blood pressure were measured using an MPC‐350 sphygmomanometer. Physicians gathered demographic data and participants' dietary intake of calcium were determined by using food frequency questionnaires. After adjusting for age, body mass index, dietary calcium, and exercise history, multiple linear regression models showed that DBP was negatively related to femoral neck BMD (β = ?0.145, P = 0.032) and just shy of significant association with femoral neck BMC (β = ?0.114, P = 0.079). SBP was correlated with femoral neck (r = ?0.171, P = 0.012) and Ward's (r = ?0.186, P = 0.006) BMD but not after adjusting for possible confounders. Further studies are needed to determine whether elevated blood pressure is causally related to the development of low bone mass. Am. J. Hum. Biol. 16:168–171, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
4.
Riera-Espinoza G Ramos J Carvajal R Belzares E Stanbury G Farías R Valderrama I Alvarez K Riera-González G 《Maturitas》2004,47(2):83-90
OBJECTIVES: An open study was carried out to evaluate changes in bone remodeling markers such as N-telopeptide (NTx), tartrate-resistant acid phosphatase (TRAP), total alkaline phosphatase (TAP), and bone alkaline phosphatase (BAP) during a 1-year continuous tibolone treatment in postmenopausal women. MATERIAL AND METHODS: Thirty-six postmenopausal women were recruited for receiving tibolone 2.5 mg per day for 1 year. Densitometry and determination of biochemical markers of bone metabolism in serum and urine were performed at 1, 3, 6, and 12 months. RESULTS: Comparing baseline with 12 month's values, BAP and all resorption markers decreased significantly. NTx began to decrease since the initiation of the treatment (baseline: 74.4 +/- 5.3; 1 month: 57.5 +/- 4.2; 12 months: 36.6 +/- 2.8). BAP increased at the first month (baseline: 37.3 +/- 2.1; 1 month: 42.6 +/- 3.0) but diminished in the following months (12 months: 23.1 +/- 1.5). TAP started to decrease significantly only after 6 months of treatment (baseline: 37.3 +/- 2.1; 12 months: 31.4 +/- 2.3) and TRAP after 3 months (baseline: 9.8 +/- 0.4; 6 months: 9.1 +/- 0.5; 12 months: 8.2 +/- 0.4). Normal bone mineral density at distal and ultradistal forearm was maintained during the 1-year treatment (baseline: 0.42 +/- 0.01; 12 months: 0.42 +/- 0.01 and baseline: 0.33 +/- 0.01; 12 months: 0.33 +/- 0.01, respectively). CONCLUSION: The use of tibolone 2.5 mg per day diminished progressively and significantly bone resorption and formation markers during 1-year treatment period. 相似文献
5.
Serum acid alpha-naphthyl phosphatase activity 总被引:2,自引:0,他引:2
6.
7.
8.
We wished to confirm and extend a previous correlational study of our group, suggesting that positive symptoms in schizophrenia were linked to an increase in certain types of memory errors, and negative symptoms to a decrease in other types of errors. A post-hoc analysis was conducted in 33 schizophrenic patients and 40 normal control subjects on memory errors collected in a free recall task and two types of recognition tasks. The memory errors were intrusions and list errors in free recall, and decision bias towards false alarms in recognition, all assumed to reflect a source-monitoring failure. In a first analysis, the patient sample was split along the median for positive symptoms as rated by the Scale for the Assessment of Positive Symptoms (SAPS). In a second analysis, it was split along the median for negative symptoms as rated by the Scale for the Assessment of Negative Symptoms (SANS). Patients with high ratings of positive symptoms made more memory errors (intrusions, list errors, false alarms) than those with low ratings, supporting the hypothesis of a link between positive symptomatology and source-monitoring failure. On the other hand, patients with high ratings of negative symptoms made fewer of these errors than the other patients. Fewer errors were specifically associated with more affective flattening, alogia and anhedonia, whereas avolition was entirely unrelated to them. 相似文献
9.
Significant progress has been made in the development of the malaria vaccine during the last 20 years. Ninety percent of the 300–500 million clinical cases of malaria per year worldwide occur in Africa. Thus, research must be directed toward the 1 million African children under 5 years of age who die every year of malaria. An asexual blood-stage vaccine, capable of reducing severe and complicated malaria and malaria-related mortality, is therefore an important public health tool in these countries. Although knowledge of the parasite's biology is incomplete, research has allowed insight into some of the mechanisms that the parasite uses to evade host immunity. This is the basis for adopting an antigenic cocktail approach toward obtaining a synthetic or recombinant subunit vaccine such as the synthetic Colombian Malaria vaccine SPf 66. During the development of Spf66, field trials under both low and high malaria endemicity areas in Latin America and Africa have been carried out. The results from these studies showed a protective efficacy ranging between 38.8 and 60.2% againstPlasmodium falciparum malaria. Given the characteristics of the normal immune response to malaria (relatively short-lived and not completely effective), it is understandable that the main goal is to try to increase the host's natural immunity. The best candidates for designing a malaria vaccine are the proteins required for parasite survival, those with low mutation rates and conserved epitopes. Because these proteins play an important role in multiple or alternative steps during the invasion process, they should be the targets against which a protective immune response should be elicited. The interaction between the malaria parasite and its host is complex. It is therefore crucial to define new ways of improving the immune response—such as directly modifying the chemical structure of epitopes or using new adjuvants or DNA immunization techniques—to produce novel vaccines against this disease. 相似文献
10.
Awareness of illness in schizophrenia 总被引:6,自引:0,他引:6
This article reviews the literature on "poor insight" or unawareness of illness in schizophrenia. A large body of knowledge representing several different perspectives on insight has developed. This work can be divided into three broad categories, suggesting an important role for insight in the phenomenology, pathophysiology, and treatment of schizophrenia. The argument is made here that many of the self-awareness deficits observed in schizophrenia are of diagnostic significance, are neurally based, and are indispensable in guiding treatment decisions. In addition, this article proposes guidelines for assessing unawareness of illness in schizophrenia and discusses the relevance of such deficits to the diagnosis of schizophrenia. 相似文献