全文获取类型
收费全文 | 962篇 |
免费 | 79篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 74篇 |
妇产科学 | 56篇 |
基础医学 | 248篇 |
口腔科学 | 27篇 |
临床医学 | 105篇 |
内科学 | 154篇 |
皮肤病学 | 37篇 |
神经病学 | 89篇 |
特种医学 | 11篇 |
外科学 | 95篇 |
综合类 | 1篇 |
预防医学 | 42篇 |
眼科学 | 2篇 |
药学 | 45篇 |
肿瘤学 | 54篇 |
出版年
2024年 | 2篇 |
2023年 | 7篇 |
2022年 | 15篇 |
2021年 | 21篇 |
2020年 | 24篇 |
2019年 | 18篇 |
2018年 | 25篇 |
2017年 | 23篇 |
2016年 | 28篇 |
2015年 | 36篇 |
2014年 | 29篇 |
2013年 | 50篇 |
2012年 | 66篇 |
2011年 | 66篇 |
2010年 | 36篇 |
2009年 | 35篇 |
2008年 | 81篇 |
2007年 | 78篇 |
2006年 | 53篇 |
2005年 | 71篇 |
2004年 | 59篇 |
2003年 | 46篇 |
2002年 | 45篇 |
2001年 | 19篇 |
2000年 | 14篇 |
1999年 | 20篇 |
1998年 | 13篇 |
1997年 | 14篇 |
1996年 | 6篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1972年 | 2篇 |
1969年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1043条查询结果,搜索用时 31 毫秒
1.
Soderstrom-Anttila V; Sajaniemi N; Tiitinen A; Hovatta O 《Human reproduction (Oxford, England)》1998,13(7):2009-2015
The health, growth and development of a cohort of children (n = 59) aged 6
months to 4 years and born after oocyte donation (OD) was compared with
that from a group of children born after in-vitro fertilization (IVF) (n =
126). The study was performed by questionnaire, and the response rate was
100% in the OD group and 95% in the IVF group. All OD children were
healthy. Three IVF children had a neurological disorder. Surgical
intervention had been carried out in 8% of the OD and 13% of the IVF
children. Height and weight development were normal, and eating and
sleeping disorders were uncommon in both groups of children. The IVF
mothers more often expressed concern about the child's behaviour than did
the OD mothers. Thirty-eight percent of the OD parents and 60% of the IVF
parents intended to tell the child about the nature of its conception (P
< 0.01). Although oocyte recipients appear to have more complications
during their pregnancies than conventional IVF patients, the general health
status of OD children aged <5 years is at least as good as that of IVF
children. Growth and development in both groups of children is similar to
that of the general population.
相似文献
2.
3.
Bharti Razdan Peter J. Marro Outi Tammela Rajiv Goel Om Prakash Mishra Maria Delivoria-Papadopoulos 《Brain research》1993,600(2):308-314
The effect of hypoxia on the structure and function of the synaptosomal membranes and myelin fraction (glial cells, neuronal cell bodies and axonal membranes) was investigated by measuring Na+,K+-ATPase activity and levels of lipid peroxidation products in cerebral cortical synaptosomal membranes and myelin fractions obtained from newborn piglets. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/Oi) using31P-NMR spectroscopy. PCr/Pi decreased from baseline of2.93 ± 0.76to0.61 ± 0.36 during hypoxia. The synaptosomal membrane Na+,K+-ATPase activity decreased from a control value of56.6 ± 3.7to40.4 ± 6.0 μgmol Pi/mg protein/h during hypoxia. The level of conjugated dienes increased from zero (reference value) to4.5 ± 2.7 nmol/mg lipid and the level of fluorescent compounds increased from23.5 ± 2.2to92.6 ± 46.4 ng quinine sulfate/mg lipid in the synaptosomal membranes during hypoxia. No change in myelin fraction Na+,K+-ATPase activity or levels of lipid peroxidation products were noted. These data indicate that sunaptosomal membranes, rich in polyunsaturated fatty acids, are more susceptible to oxygen free radical mediated lipid peroxidative damage during hypoxia. 相似文献
4.
5.
6.
Intra-uterine insemination versus cyclic, low-dose prednisolone in couples with male antisperm antibodies 总被引:1,自引:1,他引:1
A total of 46 couples with male immunological infertility enteredthe trial at the infertility clinic of the Family Federationof Finland. The men all showed a positive mixed antiglobulinreaction to immunoglobulin G in their semen; 31 men were alsotested for sperm-bound IgA immunoglobulins by flow cytometry.Serum antisperm antibodies were checked in a tray agglutinationtest. The women showed normal reproductive endocrinology andat least one patent Fallopian tube. The couples were randomizedto undergo either up to three intra-uterine inseminations (IUI),or timed intercourse with cyclic, low-dose (20 mg) prednisolonetherapy of the men. Cross-over was carried out if no pregnancyoccurred in the first stage. Timing of ovulation was based onurinary luteinizing hormone assay and transvaginal ultrasonographicmeasurements. In all, 40 couples either completed the studyor the female partner conceived. IUI was significantly better(P = 0.04) with nine pregnancies than timed intercourse withprednisolone (one pregnancy). There were no significant associationsbetween antibody levels, sperm count or motility versus theincidence of pregnancy. In male immunological infertility, well-timedIUI is an effective treatment method: results are obtained rapidlyand steroidal side-effects can be avoided. 相似文献
7.
This work discusses the strengths, limitations and validity of a novel arterial spin labeling technique when used specifically to measure perfusion in limb skeletal muscle. The technique, flow-driven arterial water stimulation with elimination of tissue signal (FAWSETS), offers several advantages over existing arterial spin labeling techniques. The primary goal of this study was to determine the perfusion signal response to changes in net hind limb flow that were independently verifiable. The range of perfusate flow was relevant to skeletal muscle during mild to moderate exercise. Localized, single voxel measurements were acquired from a 5 mm-thick slice in the isolated perfused rat hind limb at variable net flow rates. The results show that the perfusion signal is linearly proportional to net hind limb flow with a correlation coefficient of 0.974 (p = 0.0013). FAWSETS is especially well suited for studies of skeletal muscle perfusion, where it eliminates the need to compensate for magnetization transfer and arterial transit time effects. A conceptual discussion of the basic principles underlying these advantages is presented. 相似文献
8.
Single cell CGH analysis reveals a high degree of mosaicism in human embryos from patients with balanced structural chromosome aberrations 总被引:11,自引:0,他引:11
Malmgren H Sahlén S Inzunza J Aho M Rosenlund B Fridström M Hovatta O Ahrlund-Richter L Nordenskjöld M Blennow E 《Molecular human reproduction》2002,8(5):502-510
We have performed comparative genomic hybridization (CGH) analysis of single blastomeres from human preimplantation embryos of patients undergoing preimplantation genetic diagnosis (PGD) for inherited structural chromosome aberrations and from embryos of IVF couples without known chromosomal aberrations. The aim was to verify the PGD results for the specific translocation, reveal the overall genetic balance in each cell and visualize the degree of mosaicism regarding all the chromosomes within the embryo. We successfully analysed 94 blastomeres from 28 human embryos generated from 13 couples. The single cell CGH could verify most of the unbalanced translocations detected by PGD. Some of the embryos exhibited a mosaic pattern regarding the chromosomes involved in the translocation, and different segregation could be seen within an embryo. In addition to the translocations, we found a high degree of numerical aberrations including monosomies, trisomies and duplications or deletions of parts of chromosomes. All of the embryos (100%) were mosaic, containing more than one chromosomally uniform cell line, or even chaotic with a different chromosomal content in each blastomere. 相似文献
9.
Vladimir Kenis Eugeniy Melchenko Ilya Mazunin Minna Pekkinen Outi Mäkitie 《American journal of medical genetics. Part A》2021,185(1):112-118
Epiphyseal chondrodysplasia, Miura type (ECDM) is a skeletal dysplasia with tall stature and distinctive skeletal features caused by heterozygous NPR2 pathogenic variants. Only four families have been reported. We present a family with five affected individuals (mother, three sons, and daughter). The mother's phenotype was relatively mild: borderline tall stature and elongated halluces operated during childhood. The children were remarkably more severely affected with tall stature, scoliosis, and elongated toes and fingers leading to suspicion of Marfan syndrome. Progressive valgus deformities (at the hips, knees, and ankles) were the main complaints and necessitated orthopedic investigations and surgery. Radiographs showed coxa valga, scoliosis, multiple pseudoepiphyses of the fingers and toes with uneven elongation of the digits and ankle valgus. The two older brothers underwent osteotomies and guided growth for axial deformities and arthrodesis for elongated halluces. Genetic testing confirmed the clinical diagnosis of ECDM: all affected individuals had a heterozygous c.2647G>A (p.Val883Met) NPR2 variant in a highly conserved region in the carboxyl‐terminal guanylyl cyclase domain. This two‐generation family elucidates the clinical and radiological variability of the disease. These rare cases are important to gain further understanding of the fundamental processes of growth regulation. 相似文献
10.
A TLR4 polymorphism is associated with asthma and reduced lipopolysaccharide-induced interleukin-12(p70) responses in Swedish children 总被引:11,自引:0,他引:11
Fagerås Böttcher M Hmani-Aifa M Lindström A Jenmalm MC Mai XM Nilsson L Zdolsek HA Björkstén B Söderkvist P Vaarala O 《The Journal of allergy and clinical immunology》2004,114(3):561-567
BACKGROUND: Bacterial signals play an important role in the maturation of the immune system. Polymorphisms in genes coding for receptors to bacterial components can alter the immune responsiveness of the host to microbial agents and may indicate the development of aberrant immune responses that are associated with immune-mediated diseases such as atopic diseases. OBJECTIVE: The study's objective was to investigate the relationship between TLR4 and CD14 gene polymorphisms, the LPS responsiveness of PBMCs, and the presence of asthma and allergic rhinoconjunctivitis in children. METHODS: The TLR4 (Asp299Gly) and CD14/-159 polymorphisms were determined in 115 Swedish children aged 8 and 14 years. LPS-induced IL-12(p70), IL-10, and IFN-gamma responses of PBMCs from 69 of the children were analyzed by means of ELISA. The levels of soluble CD14 in serum samples were analyzed by means of ELISA, and the total IgE levels were analyzed by means of UniCAP Total IgE (Pharmacia Diagnostics, Uppsala, Sweden). RESULTS: Decreased LPS-induced IL-12(p70) and IL-10 responses were associated with the TLR4 (Asp299Gly) polymorphism and independently with asthma, especially atopic asthma. The TLR4 (Asp299Gly) polymorphism was associated with a 4-fold higher prevalence of asthma in school-aged children (adjusted odds ratio 4.5, 95% CI 1.1-17.4) but not to allergic rhinoconjunctivitis. CONCLUSION: A TLR4 polymorphism modifies innate immune responses in children and may be an important determinant for the development of asthma. This may influence the outcome of intervention studies that use microbial stimuli as immune modulators. 相似文献