全文获取类型
收费全文 | 767篇 |
免费 | 39篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 67篇 |
妇产科学 | 26篇 |
基础医学 | 69篇 |
口腔科学 | 37篇 |
临床医学 | 79篇 |
内科学 | 182篇 |
皮肤病学 | 16篇 |
神经病学 | 51篇 |
特种医学 | 19篇 |
外科学 | 136篇 |
综合类 | 19篇 |
预防医学 | 28篇 |
眼科学 | 13篇 |
药学 | 30篇 |
中国医学 | 1篇 |
肿瘤学 | 31篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 15篇 |
2020年 | 10篇 |
2019年 | 18篇 |
2018年 | 29篇 |
2017年 | 14篇 |
2016年 | 11篇 |
2015年 | 24篇 |
2014年 | 28篇 |
2013年 | 53篇 |
2012年 | 47篇 |
2011年 | 51篇 |
2010年 | 40篇 |
2009年 | 40篇 |
2008年 | 60篇 |
2007年 | 74篇 |
2006年 | 81篇 |
2005年 | 63篇 |
2004年 | 47篇 |
2003年 | 29篇 |
2002年 | 27篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有814条查询结果,搜索用时 15 毫秒
51.
Deniz Inal-Ince Sema Savci Hulya Arikan Melda Saglam Naciye Vardar-Yagli Meral Bosnak-Guclu Deniz Dogru 《The spine journal》2009,9(12):981-986
Background contextNeuromuscular disorders (NMD) are characterized by loss of lung volume and respiratory muscle weakness, but the effects of scoliosis on lung function are unclear.PurposeTo compare pulmonary function and respiratory muscle strength in patients with NMD with and without scoliosis as well as in healthy controls.Study design/settingProspective comparison of pulmonary function testing and respiratory muscle strength were made at the pediatric pulmonology and cardiopulmonary rehabilitation units of a university hospital.Patient sampleTwenty-two patients with NMD and scoliosis, 17 patients with NMD without scoliosis, and 24 age- and sex-matched healthy controls. Outcome measures were compared in patients with NMD with and without scoliosis and healthy subjects using Student t test, Mann-Whitney U test, chi-square test, one-way analysis of variance (ANOVA), Kruskal-Wallis one-way ANOVA, Pearson correlation coefficients, and Spearman rank correlation, as appropriate.Outcome measures1) Pulmonary function: forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEF), forced expiratory flow between 25% and 75% of FVC (FEF25–75%), and maximum expiratory flows at 75%, 50%, and 25% of FVC (MEF75, MEF50, and MEF25, respectively); 2) oxygen saturation: pulse oxymeter reading; and 3) respiratory muscle strength: maximal inspiratory mouth pressure (MIP) and maximal expiratory mouth pressure (MEP).MethodsPulmonary function, oxygen saturation, MIP, and MEP were measured and compared in patients with NMD, patients with and without scoliosis, and in healthy subjects.ResultsThe patients with NMD, both with and without scoliosis, had significantly lower PEF, MIP, MEP, % predicted MIP (%MIP), and % predicted MEP (%MEP) than those of healthy subjects (p<.05). The patients with NMD and scoliosis had significantly lower values than those with NMD without scoliosis and controls (p<.05) for FVC, FEV1, and FEF25–75%.ConclusionBoth inspiratory and expiratory muscle strength were diminished in patients with NMD compared with healthy controls. Significant differences were also noted in pulmonary function in patients with NMD with or without scoliosis. This suggests that NMD may impact respiratory function independently of the effects of scoliosis. Clinicians treating patients with NMD should be aware of the possibility of compromised respiratory function in these patients to address possible complications. 相似文献
52.
Dagli M Sivas Acar F Karabulut H Eryilmaz A Erkol Inal E 《Rheumatology international》2007,27(6):511-516
The aim of this study was to investigate cochlear functions in patients with ankylosing spondilitis (AS). Prospective, case
control study. Twenty-eight AS patients (56 ears) and 25 healthy control subjects (50 ears) were included in the study. Pure-tone
audiometry at 250, 500, 1,000, 2,000, 4,000, 6,000 Hz and immittance measures including tympanometry and acoustic reflex and
DPOAEs (Distortion Product Otoacoustic Emission) testing were performed in the patients and controls. Pure-tone audiometry
findings of the patients and controls were significantly different in all frequencies (P < 0.05). Sensorineural hearing loss was found in 10 patients (35%) that was bilateral in seven and unilateral in three patients.
On DPOAE testing, there was no statistically significant difference between the levels of noise floor of the patients and
controls (P > 0.05). However, the DPOAE responses of the patients and controls were significantly different in 3,000, 4,000, 5,000 and
6,000 Hz frequencies (P < 0.05). There is a damage of outer hair cells in patients with AS, and damaged outer hair cell regions mostly corresponds
to the basal and mid-portions of the cochlea. 相似文献
53.
54.
Savas B Ensari A Percinel S Kuzu I Kuzu MA Bektas M Cetinkaya H Kursun N 《Acta gastro-enterologica Belgica》2007,70(4):339-344
BACKGROUND AND STUDY AIMS: The purpose of the current study was to investigate the role of beta-catenin, E-cadherin and P-cadherin in colorectal carcinogenesis using tissue array method. PATIENTS AND METHODS: Core tissue biopsies were taken from paraffin-embedded tissue blocks of 167 cases including 26 normal mucosae (NM), 99 colorectal polyps (10 hyperplastic polyps (HP), 8 traditional serrated (TSA), 17 tubular (TA), 37 tubulovillous (TVA), and 27 villous adenomas (VA)), 14 adenomas with intramucosal carcinoma (ACA), and 28 colorectal cancers (CCA). Immunohistochemistry was performed using antibodies to beta-catenin, E-cadherin, and P-cadherin. Distribution of positivity was assessed using percentage expression while an arbitrary grading scale was used for staining intensity. RESULTS: beta-catenin expression was cytoplasmic, membranous, and nuclear. Both E-cadherin and P-cadherin expressions were confined to cytoplasmic-membranous compartments. Membranous expression of beta-catenin significantly decreased in CCA (p < 0.01). Nuclear beta-catenin expression significantly increased in close correlation with neoplastic sequence reaching its highest expression in ACA and CCA (p < 0.001). Polyps with intraepithelial neoplasia (IEN) showed significantly higher nuclear beta-catenin expression in parallel with increasing grades of IEN (p < 0.001). E-cadherin and P-cadherin expression increased in polyps, whereas a significant decrease in their expression was observed in CCA (p < 0.001) while E-cadherin expression significantly increased in CCA compared to NM (p < 0.001), no such difference was observed in P-cadherin expression. CONCLUSIONS: Nuclear beta-catenin expression correlating with the grade of IEN in polyps and carcinomas supports its role in colorectal carcinogenesis. E-cadherin and P-cadherin expressions in adenomas suggest that these molecules might have role in adenoma formation though not necessarily be involved in neoplastic progression. 相似文献
55.
Uyar AS Yagmurdur H Fidan Y Topkaya C Basar H 《Journal of neurosurgical anesthesiology》2008,20(3):174-179
We tested dexmedetomidine, an alpha2 agonist, for its ability to decrease heart rate, arterial blood pressure, and neuroendocrinal responses to skull-pin head-holder application during craniotomy. In a randomized, double-blinded, placebo-controlled study, 40 patients undergoing craniotomy with attachment of a pin head-holder were randomly assigned to one of 2 equal groups. The placebo group received saline, whereas the treatment group (DEX group) received a single bolus dose of dexmedetomidine (1 microg/kg) intravenously over 10 minutes before induction of anesthesia. Arterial blood pressure, heart rate, and sequential concentrations of circulating cortisol, prolactin, insulin, and blood glucose were measured. Relative to baseline and the other group, arterial blood pressure and heart rate decreased significantly after the administration of dexmedetomidine through skull pinning (P<0.05). In the placebo group, patients' heart rate and arterial blood pressure measures increased at 1 and 5 minutes after skull-pin insertion, compared with baseline and the DEX group (P<0.05). In both groups, plasma cortisol, prolactin, and blood glucose increased significantly relative to baseline after skull-pin insertion. However, the values were significantly higher in the placebo group compared with the DEX group (P<0.05). Although insulin levels were not significantly altered in the DEX group, the plasma concentrations of insulin decreased significantly after pin insertion in the placebo group. Our results suggested that, a single bolus dose of dexmedetomidine before induction of anesthesia attenuated the hemodynamic and neuroendocrinal responses to skull-pin insertion in patients undergoing craniotomy. 相似文献
56.
57.
Karatas H Gurer G Pinar A Soylemezoglu F Tezel GG Hascelik G Akalan N Tuncer S Ciger A Saygi S 《Journal of the neurological sciences》2008,264(1-2):151-156
OBJECTIVE: The objective of this study is to investigate the presence of viral DNAs of HSV-1, HSV-2, HHV-6, HHV-8, and CMV in hippocampus of the patients with mesial temporal lobe epilepsy (MTLE) syndrome. METHODS: Pathological specimens were obtained from 33 patients with MTLE undergone temporal lobectomy with amygdalo-hippocampectomy due to intractable seizures. Autopsy materials from the hippocampus of 7 patients without neurological disease were used as controls. The data was also correlated with the clinical history of patients including febrile convulsions, age, and history of CNS infections. Real-time polymerase chain reaction method was performed for detection of DNAs of these viruses. RESULTS: HHV-6, HSV-1 and HHV-8 were detected in the hippocampus of 3, 2 and 1 patients with MTLE respectively. None of the hippocampus of patients with MTLE was positive for DNA of HSV-2 and/or CMV. Three patients with positive HHV-6 DNAs had febrile convulsions and family history for epilepsy. None of our control specimens showed PCR positivity to any of the 5 tested viruses. CONCLUSIONS: Our study is the first to report the presence of HHV-8 viral genome in the brain tissue of patient with MTLE. Viral DNAs were detected in a total of 18% of the patients in this study; we can conclude that activity of the latent virus in patients with hippocampal sclerosis should be more extensively studied to establish its role in active infection. 相似文献
58.
Objective The aim of this study was to investigate the role of adhesion molecules in epididymal injury induced by ischemia-reperfusion
(I-R) in the rats.
Study design About 20 male Sprague-Dawley rats were separated into two groups. A sham operation was performed in group 1 (control). In
group 2 (I-R), following 6 h of unilateral spermatic cord torsion, 1-h detorsion of the testis was performed. Then, epididymides
were removed to measure the tissue levels of malondialdehyde (MDA) and to make histological examination.
Results Malondialdehyde values increased in group 2. In group 2, the rats demonstrated significant disorganization of the epithelium
and loss of microvilli in the epididymal tissue. No abnormal microscopic findings of the epididymis of the rats in the control
group. The tenascin expression in the interstitial area of the epididymis was intense in group 2. Intercellular adhesion molecule-1
(ICAM-1) expression by intense brown staining was seen along the basement membrane in epididymal tissue from I-R group rats.
The microvillus sites of the epithelia in I-R group were stained mildly by lectin.
Conclusion The increased expression of adhesion molecules found in epididymal injury induced during of postischemic reperfusion may implicate
importance of inflammatory infiltration. 相似文献
59.
Inflammation in the liver is an extraintestinal manifestation that is frequently seen during inflammatory bowel diseases (IBD). The authors investigated histopathologycal, ultrastructural and antioxidant effects of dexmedetomidine (Dex) on liver during trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease. Thirty-two BALB/c mice were divided (n?=?8) as follows: control; Dex (dexmedetomidine) (30?μg/kg) for 6 days; TNBS 150?μL, TNBS?+?ethanol (50% w/v) intrarectally; TNBS?+?Dex. The histopathological and ultrastructural changes were evaluated. The levels of malondialdehyde (MDA), activity of antioxidant enzymes (GPx and SOD) were measured in liver tissue. Induction of colitis induced histopathological and ultrastructural changes of damage in liver. Those changes were markedly reduced in the TNBS?+?Dex group and that reduction was even significant in comparison to the TNBS group. MDA levels were significantly higher in the TNBS group and dexmedetomidine significantly elevated SOD levels in the TNBS?+?Dex group. These results suggest that the administration of dexmedetomidine reduces the histopathological and ultrastructural damage and increases the defense capacity against oxidative damage on liver in this IBD mice model. 相似文献
60.
IntroductionThe present study aimed to compare the torsional strength of the initial files of the Mtwo (VDW, Munich, Germany) and novel Rotate systems (VDW, Munich, Germany) with the ProGlider (Dentsply Sirona, Ballaigues, Switzerland) and R-Pilot (VDW) glide path instruments.MethodsThe Mtwo (10/.04), ProGlider (16/.02), R-Pilot (12.5/.04), and Rotate (15/.04) glide path files were compared regarding their torsional strength, which was tested using a specially designed test device (N = 20). The data obtained were statistically analyzed at 5% significance level using 1-way analysis of variance and the post hoc Tukey test. The fragment surfaces and separated instruments were examined with ×50, ×100, and ×1000 magnification under a scanning electron microscope.ResultsThe R-Pilot group showed the highest torsional strength value among all groups (P < .05), whereas there was no significant difference between the torsional strength values of the Mtwo and ProGlider groups (P > .05). The Rotate group had the lowest torsional strength among all groups (P < .05). The Mtwo group showed the lowest angle of rotation among all groups (P < .05).ConclusionsAlthough the R-Pilot glide path file exhibited the highest torsional strength in all groups, Rotate showed the highest angle of rotation. Differences in torsional resistance of the instruments may be associated with their manufacturing methods and design features. 相似文献