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41.
42.
The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen 总被引:19,自引:2,他引:19
Manning JT; Scutt D; Wilson J; Lewis-Jones DI 《Human reproduction (Oxford, England)》1998,13(11):3000-3004
The differentiation of the urinogenital system and the appendicular
skeleton in vertebrates is under the control of Hox genes. The common
control of digit and gonad differentiation raises the possibility that
patterns of digit formation may relate to spermatogenesis and hormonal
concentrations. This work was concerned with the ratio between the length
of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in
right and left hands has a sexually dimorphic pattern; in males mean 2D:4D
= 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females
mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal
length. The dimorphism is present from at least age 2 years and 2D:4D is
probably established in utero; (ii) high 2D:4D ratio in right hands was
associated with germ cell failure in men (P = 0.04); (iii) sperm number was
negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men
testosterone concentrations were negatively related to right hand 2D:4D and
in women and men LH (right hand), oestrogen (right and left hands) and
prolactin (right hand) concentrations were positively correlated with 2D:4D
ratio and (v) 2D:4D ratio in right hands remained positively related to
luteinizing hormone and oestrogen after controlling for sex, age, height
and weight.
相似文献
43.
44.
Bioenergetic reprogramming of articular chondrocytes by exposure to exogenous and endogenous reactive oxygen species and its role in the anabolic response to low oxygen 下载免费PDF全文
H. K. Heywood D. A. Lee 《Journal of tissue engineering and regenerative medicine》2017,11(8):2286-2294
Monolayer culture is integral to many cell‐based cartilage repair strategies, but chondrocytes lose regenerative potential with increasing duration in vitro. This coincides with elevated reactive oxygen species (ROS) levels and a bioenergetic transformation characterized by increasing mitochondrial function. This study investigates ROS as stimuli for bioenergetic reprogramming and the effect of antioxidants on the propensity of chondrocytes to regenerate a cartilaginous matrix. Articular chondrocytes were cultured in monolayer under a 2% O2 atmosphere. Oxidative stress was increased using 50 μm H2O2 or a 20% O2 culture atmosphere, or decreased using the antioxidant N‐acetyl‐cysteine (NAC). Mitochondrial function was characterized using 200 nm Mitotracker green and an oxygen biosensor. After two population doublings ± NAC, chondrocytes were encapsulated in alginate beads (1 × 107 cells/ml) for an additional 10 days before DMB assay of glycosaminoglycan content. The beads were cultured under both 20% O2 and the more physiological 5% O2 condition. Chondrocytes expanded in 20% O2 exhibited elevated mitochondrial mass and functional capacity, which was partially mimicked by the exogenous ROS, H2O2. Oligomycin treatment revealed that the increased oxygen consumption was coupled to oxidative phosphorylation. NAC limited these markers of bioenergetic reprogramming during culture‐expansion with no significant effect on subsequent GAG production under 20% O2. However, NAC treatment in monolayer abolished the hypoxic induction of GAG in alginate beads. This supports the hypothesis of a causal relationship between exposure to ROS and acquired mitochondrial function in chondrocytes. Additionally, mitochondrial function may be required for the hypoxic induction of GAG synthesis by chondrocytes. © 2015 The Authors. Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons, Ltd. 相似文献
45.
2010年欧洲神经病学联盟阿尔茨海默病诊疗指南 总被引:2,自引:0,他引:2
一、概述
(一)目的
2008年成立工作组的目的是修改前一版欧洲神经病学联盟(EFNS)的阿尔茨海默病(AD)诊疗指南.前一版指南采用了第4版诊断和统计手册(DSM Ⅳ)及美国国立神经病学、语言障碍和脑卒中研究所-阿尔茨海默病及相关疾病学会(NINCDS-ADRDA)对痴呆综合征和AD的诊断标准. 相似文献
46.
Queenan JT Jr; Veeck LL; Toner JP; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(7):1573-1576
In-vitro fertilization patients (n = 15) at risk of ovarian
hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day
of human chorionic gonadotrophin administration and 25 or more follicles of
intermediate or large size) underwent aspiration of all follicles and
cryopreservation of all fertilized oocytes at the pronuclear stage.
Patients were monitored for up to 2 weeks post- retrieval. Subsequent
transfer of cryopreserved-thawed embryos was performed in programmed cycles
using exogenous oestrogen and progesterone for endometrial preparation. Two
patients (13%) developed OHSS necessitating hospitalization and vaginal
aspiration of ascitic fluid. Two other patients (13%) developed moderate
OHSS requiring ascitic fluid vaginal aspiration in the office setting, with
dramatic improvement of the condition. Subsequent transfer of
cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per
transfer and ongoing or delivery rates of 42 and 67% per transfer and per
patient respectively. By eliminating pregnancy potential with
cryopreservation of all prezygotes and examining the pregnancy potential
with subsequent cryopreserved-thawed transfers, it is concluded that OHSS
is reduced, but not eliminated for patients at risk. Subsequent transfer of
cryopreserved-thawed prezygotes in a programmed cycle with exogenous
steroids yields an excellent pregnancy rate.
相似文献
47.
Effect of the menstrual cycle on detection and typing of human papillomavirus in uterine cervical cells 总被引:1,自引:0,他引:1
P J McNicol F B Guijon M Paraskevas E Heywood M J Gray R C Brunham 《American journal of obstetrics and gynecology》1990,162(4):1037-1041
We observe fluctuations in human papillomavirus detection and variation in genotyping between sequential cervical cell specimens analyzed by filter in situ hybridization. Furthermore, specimen adequacy for analysis varies. To determine whether these phenomena are correlated with menstrual cycle stage at the time of sampling, we analyzed cervical cell specimens from women with cervical intraepithelial neoplasia. Specimens were categorized on the basis of a 28-day menstrual cycle and were analyzed by hybridization to combined probes for virus types 6 and 11 or types 16 and 18. Specimen adequacy was determined by hybridization to a human Alu I repetitive deoxyribonucleic acid probe. Analysis of data with chi 2 revealed that fluctuations in virus detection and type variation are unrelated to menstrual cycle stage. Specimen adequacy is stage-dependent for women who take oral contraceptives. Whereas specimens can be collected at any time other than the first week of the menstrual cycle, accurate determination of infection status requires multiple assessments. 相似文献
48.
The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases). 相似文献
49.
Socio-economic characteristics of adult frequent attenders in general practice: secondary analysis of data 总被引:8,自引:0,他引:8
OBJECTIVE: This study was carried out to determine the effect of a range of socio-economic features on frequent attendance in general practice from a large database of general practice consultations using two definitions of frequent attendance. METHODS: Secondary analyses were carried out of data from the Fourth National Survey of Morbidity in General Practice covering 60 general practices in England and Wales. A total of 283 842 adult patients and their consultations between September 1991 and August 1992 were examined. The main outcome measure was the odds ratio of being a frequent attender (95% confidence intervals). RESULTS: Using a definition of 12+ consultations/year, men were less likely to be frequent attenders (OR 0.14, 95% CI 0.13-0.17); however, the difference between men and women lessens with age. Patients who were more likely to be frequent attenders included those who were divorced or widowed (1.41, 1.31-1.51); from social classes IIIM (1.23, 1.17-1.29) and IV/V (1.33, 1.26-1.41); South Asian people (1.38, 1.16-1.65); or unemployed (1.61, 1.46-1.77). Other factors signifying isolation or poverty were also linked to frequent attendance. Using the definition of '6+ consultations for minor problems' produced broadly similar results although the relative weight of the factors showed some differences. CONCLUSIONS: Socio-economic factors were important indicators of frequent attendance in general practice. Results were very similar using either definition, suggesting that both are valid for further work. Furthermore, frequent attendance is a complex process associated with many factors outside the control of the GP. 相似文献
50.
Patel NK Plaha P O'Sullivan K McCarter R Heywood P Gill SS 《Journal of neurology, neurosurgery, and psychiatry》2003,74(12):1631-1637
OBJECTIVE: Bilateral chronic high frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has emerged as an appropriate therapy for patients with advanced Parkinson's disease refractory to medical therapy. Advances in neuroimaging and neurophysiology have led to the development of varied targeting methods for the delivery of this treatment. Intraoperative neurophysiological and clinical monitoring is regarded by many to be mandatory for accurate STN localisation. We have examined efficacy of bilateral STN stimulation using a predominantly magnetic resonance imaging (MRI)-directed technique. METHODS: DBS leads were stereotactically implanted into the STN using an MRI directed method, with intraoperative macrostimulation used purely for adjustment. The effects of DBS were evaluated in 16 patients followed up to 12 months, and compared with baseline assessments. Assessments were performed in both off and on medication states, and were based on the Unified Parkinson's Disease Rating Scale (UPDRS) and timed motor tests. Functional status outcomes were examined using the PDQ-39 quality of life questionnaire. A battery of psychometric tests was used to assess cognition. RESULTS: After 12 months, stimulation in the off medication state resulted in significant improvements in Activities of Daily Living and Motor scores (UPDRS parts II and III) by 62% and 61% respectively. Timed motor tests were significantly improved in the off medication state. Motor scores (UPDRS part III) were significantly improved by 40% in the on medication state. Dyskinesias and off duration were significantly reduced and the mean dose of L-dopa equivalents was reduced by half. Psychometric test scores were mostly unchanged or improved. Adverse events were few. CONCLUSIONS: An MRI directed targeting method for implantation of DBS leads into the STN can be used safely and effectively, and results are comparable with studies using intraoperative microelectrode neurophysiological targeting. In addition, our method was associated with an efficient use of operating time, and without the necessary costs of microelectrode recording. 相似文献