全文获取类型
收费全文 | 1033篇 |
免费 | 49篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 18篇 |
妇产科学 | 23篇 |
基础医学 | 126篇 |
口腔科学 | 9篇 |
临床医学 | 60篇 |
内科学 | 179篇 |
皮肤病学 | 6篇 |
神经病学 | 188篇 |
特种医学 | 9篇 |
外科学 | 119篇 |
综合类 | 6篇 |
预防医学 | 54篇 |
眼科学 | 88篇 |
药学 | 130篇 |
肿瘤学 | 52篇 |
出版年
2023年 | 6篇 |
2022年 | 19篇 |
2021年 | 24篇 |
2020年 | 12篇 |
2019年 | 20篇 |
2018年 | 25篇 |
2017年 | 17篇 |
2016年 | 17篇 |
2015年 | 15篇 |
2014年 | 36篇 |
2013年 | 41篇 |
2012年 | 71篇 |
2011年 | 61篇 |
2010年 | 44篇 |
2009年 | 28篇 |
2008年 | 58篇 |
2007年 | 72篇 |
2006年 | 68篇 |
2005年 | 66篇 |
2004年 | 85篇 |
2003年 | 76篇 |
2002年 | 74篇 |
2001年 | 14篇 |
2000年 | 8篇 |
1999年 | 12篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 6篇 |
1993年 | 11篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1083条查询结果,搜索用时 15 毫秒
61.
Obersztyn E Mazurczak T Helias-Rodzewicz Z Bocian E Kutkowska-Kazmierczak A 《Medycyna wieku rozwojowego》2003,7(3):389-401
Intellectual disability, defined as an IQ less than 70, occurs in 2-3% of the population and is both a medical and social problem of outstanding importance. Establishing its aetiology is not always easy, but it is a necessary condition in providing genetic counseling for families. Until now, the aetiology of mental retardation remains unknown in about half of the cases. Chromosomal aberrations are found in about 30-40% of moderately and profoundly intellectually impaired. Submicroscopic chromosomal aberrations involving the telomeric regions of chromosomes discovered in the recent years, are responsible for 4-9% cases of idiopathic mental retardation. Identification of very small structural rearrangements in the telomeric regions of the chromosomes requires another strategy than those applied in routine classic methods of chromosomal analysis (fluorescence in situ hybridisation in situ FISH). We present several cases of mental retardation with congenital defects and dysmorphic features which occurred in one family. Submicroscopic aberration in the telomeric regions of chromosomes 7 and 10 was revealed as a cause of mental retardation in this family. That aberration was a result of familial reciprocal translocation which had been not previously identified by routine cytogenetic methods. Detailed retrospective clinical characteristics of the proband and his affected relatives is presented. Variable clinical expression in presented cases in relation to difficulties in diagnosis and genetic counseling is discussed. 相似文献
62.
Szpakowski M Wilczyński JR Wieczorek A Raczkowska Z Malinowski A Nowak M Kamiński T Szpakowski A Władziński J Jaczewski B Sobantka S Podciechowski L Krawczyk T 《Ginekologia polska》2002,73(4):379-385
OBJECTIVES: The differences exist in concerning the estimation of number and histopathological type of ovarian tumors in pregnancy. MATERIAL AND METHODS: From all 41,661 labours which took place in our Institute between 1990-2000 retrospective analysis of medical documentation of 11,050 caesarean sections (CS) as well as histopathological protocols were performed. RESULTS: The prevalence of ovarian tumors removed during CS performed between 28-41 weeks of gestation was 0.19%. The prevalence of malignancy was low (0.005% of all labours). Unilateral cystectomy was found to be the most frequent kind of surgery and adult teratoma, serous cyst and paraovarian cyst as most common histopathological tumor types. CONCLUSION: We conclude that ovarian tumors, especially of malignant type are rarely the complication of pregnancy. The most are benign, small, unilocular and smooth-wall cystic tumors. 相似文献
63.
64.
Tissue oxygen reactivity and cerebral autoregulation after severe traumatic brain injury 总被引:5,自引:0,他引:5
OBJECTIVE: To study the relationship between arterial blood pressure, intracranial pressure, directly measured brain tissue oxygenation (PtiO2), and middle cerebral artery blood flow velocity in severely head-injured patients. DESIGN: Prospective study. SETTING: Neurosurgical intensive care unit.PATIENTS A total of 14 patients with severe head injury. INTERVENTIONS: Pharmacologic blood pressure manipulations using norepinephrine. MEASUREMENTS AND MAIN RESULTS: We assessed the magnitude of PtiO2 related to changes in cerebral perfusion pressure in 12 of the patients. We calculated in all the static rate of regulation, which is an index to describe the change of cerebrovascular resistance, using cerebral artery blood flow velocity in relation to changing cerebral perfusion pressure. Finally, we calculated the rate of change in PtiO2, which quantifies the percentage of change in PtiO2 divided by the percentage of change in cerebral perfusion pressure. It is a new marker for cerebral tissue oxygen regulation based on direct measurement of PtiO2. There was a plateau phase for the cerebral perfusion pressure-PtiO2 relation that was similar to the autoregulatory plateau seen in the relationship between cerebral perfusion pressure and cerebral artery blood flow velocity. The rate of change in PtiO2 demonstrated a significant correlation with the static rate of regulation (R = -.61, <.05). A decrease in intracranial pressure when arterial blood pressure increased from 70 to 90 mm Hg was strongly correlated with static rate of regulation (R =.79, <.001). CONCLUSIONS Cerebral tissue PO2 demonstrates a plateau phase similar to what is known about cerebral blood flow velocity, which suggests a close link between cerebral blood flow and oxygenation. Static cerebral autoregulation is significantly correlated with cerebral tissue oxygen reactivity. 相似文献
65.
The aim of the present study was to examine a potential anxiolytic-like action of (+)-7-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (7-OH-DPAT), a preferential dopamine D(3) receptor agonist, and (N-[4-[4-(2-methoxyphenyl)-1-piperazinyl]butyl]-2-naphthylcarboxamide (BP 897), partial dopamine D(3) receptor agonist. Diazepam was used as a reference compound. The anxiolytic-like effect of those drugs was tested in the conflict drinking test (Vogel test) in male Wistar rats. The obtained results showed that 7-OH-DPAT and BP 897 (like diazepam) induced anxiolytic-like effects in the conflict drinking test. 7-OH-DPAT (0.05 and 0.1 mg/kg), BP 897 (0.5 mg/kg) and diazepam (5 and 10 mg/kg), tested at the effective doses in an animal model, did not affect motor coordination but produced significant reduction in exploratory activity in the open field test. These data suggest that preferential dopamine D(3) agonists may play a role in the therapy of anxiety, however, further studies are necessary to elucidate the mechanism of these actions. 相似文献
66.
67.
Koziczak R Gonciarz M Krokosz A Szweda-Lewandowska Z 《Journal of radiation research》2003,44(3):217-222
Human erythrocyte suspensions in an isotonic Na-phosphate buffer, pH 7.4, of hematocrit of 2% were exposed under air to gamma radiation at a dose rate of 2.2 kGy. Erythrocytes were irradiated with single doses, and identical doses split into two fractions with an interval time of 3.5 h between following exposures. The obtained results indicated that the irradiation of enucleated human erythrocytes with split doses caused a reduction of hemolysis (2.4 times), a decrease in the level of damage to membrane lipids and the contents of MetHb, compared with identical single doses. However, the splitting of radiation doses did not change the level of damage to the membrane proteins, as was estimated with a maleimide spin label. The obtained results suggest that a decrease in the level of damage to lipids was related to a decrease in hemolysis. 相似文献
68.
Gooskens I Schmidt EA Czosnyka M Piechnik SK Smielewski P Kirkpatrick PJ Pickard JD 《Acta neurochirurgica》2003,145(7):527-32; discussion 532
OBJECTIVES: Patients with carotid artery stenotic disease and poor cerebral haemodynamic reserve are in increased risk of stroke. Haemodynamic reserve can be estimated by measuring cerebrovascular reactivity induced by breathing CO2 and pressure-autoregulation by analyzing spontaneous slow fluctuation in arterial pressure and MCA blood flow velocity. We evaluated the relationship between clinical status, CO2 reactivity, pressure-autoregulation and other haemodynamic variables derived from Transcranial Doppler ultrasonography in patients with carotid artery disease. METHODS: 38 patients were investigated. Arterial pressure and blood flow velocity were monitored during CO2 reactivity tests. Arterial pressure-corrected and non-corrected indices of CO2 reactivity were calculated to compare an influence of rise in arterial pressure during the test. The pressure-autoregulation index was calculated as correlation coefficient between slow waves in blood flow velocity and arterial pressure. RESULTS: The increase in CO2 produced a consistent rise in arterial pressure and blood flow velocity and weakened the pressure autoregulation. The value of pressure-corrected CO2 reactivity was lower (p<0.0001) than the non-corrected one, indicating that the rise in arterial pressure during the test tends to over-estimate CO2 reactivity. The pressure-corrected reactivity was correlated with pressure autoregulation (r=-0.46; p<0.005). Both CO2 reactivity and pressure-autoregulation index correlated with a degree of carotid artery stenosis. Side-to-side difference of TCD pulsatility index demonstrated a close relationship with the asymmetry of stenosis (r=-0.61; p<0.0002) and symptoms (r=-0.49; p<0.003). CONCLUSIONS: When calculating CO2 reactivity in patients with carotid artery disease, changes in arterial pressure should be considered. Both CO2 reactivity and pressure-autoregulation describe the magnitude of haemodynamic deficit caused by stenosis, pulsatility index expresses the asymmetry of stenosis. 相似文献
69.
Use of chitosan in medicine and biomedical engineering 总被引:7,自引:0,他引:7
Applicability of different forms of chitosan in medicine and biomedical engineering has been discussed on the basis of a literature survey. Attention was paid to the use of chitosan as a drug carrier and as a pharmacological agent in the treatment of hypercholesterolemia. Suitability of the polymer was proved in the process of blood purification (LDL-apheresis, haemoperfusion, dialysis) and wound healing (dressings). A possibility of using it in biohybrid artificial organs and as athrombogenic surfaces was also mentioned. 相似文献
70.
Obrebowski A Walczak M Swidziński P Karlik M Kurywczak-Grykiel K Obrebowska-Karsznia Z 《Otolaryngologia polska. The Polish otolaryngology》2003,57(4):531-535
The aim of the paper was to present the results of the objective audiological assessment of 48 babies and infants at the age of 1-16 months, referred the Department of Phoniatrics and Audiology in Poznań (Poland) from January 2001 to July 2002. The children were selected in neonatal hearing screening, based on the OAE, questionnaire of hearing loss with high risk factors. We discuss high percentage of false positive results of OAE, late referrals for hearing screening, difficulties of follow-up. 相似文献