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71.
Murat H. Sipahioglu Hamit Kucuk Aydin Unal Mehmet G. Kaya Fatih Oguz Bulent Tokgoz Oktay Oymak Cengiz Utas 《Peritoneal dialysis international》2012,32(1):73-80
♦ Background: Cardiovascular (CV) disease is a major cause of morbidity and mortality in patients with end-stage renal disease. In recent years, arterial stiffness has taken on great importance in the pathophysiology of CV diseases. The independent predictive value of arterial stiffness for CV events and for all-cause and CV mortality has been demonstrated in the general population and in hemodialysis patients. Our aim in this study was to determine the relationship of arterial stiffness with mortality and fatal and nonfatal CV events in peritoneal dialysis (PD) patients.♦ Methods: In this prospective observational cohort study with 2 years of follow-up, we studied a cohort of 156 PD patients with a mean follow-up of 19.2 ± 6.4 months. At baseline, echocardiography and standard clinical and biochemical analyses were performed in all patients and in 28 healthy subjects. Aortic stiffness index beta (ASIβ, a surrogate marker of arterial stiffness) was calculated as follows:
♦ Results: During the follow-up period, 25 of the patients (16.0%) died, and 10 of those deaths had CV causes. Nonfatal CV events occurred in 15 patients. The median ASIβ was greater in PD patients than in control subjects (4.2 vs. 3.5; interquartile range: 3.2 – 5.5 vs. 2.5 – 4.8; p = 0.028]. In the fully adjusted multivariate Cox regression analysis (co-variates: age, sex, albumin, hemoglobin, diabetes mellitus, comorbid CV disease, left ventricular mass index, residual glomerular filtration rate, dialysate-to-plasma ratio of creatinine, Kt/V urea, left ventricular ejection fraction, duration of dialysis, smoking), ASIβ independently predicted fatal and nonfatal CV events (hazard ratio: 1.239; 95% confidence interval: 1.103 to 1.392), but not all-cause mortality.♦ Conclusions: Our results provide the first direct evidence that arterial stiffness is an independent risk predictor of adverse CV outcome in PD patients. 相似文献
72.
Gozde Unal Serhan Gurmeric Stéphane Guy Carlier 《The international journal of cardiovascular imaging》2010,26(7):809-816
The objectives of this article are (i) to utilize computer methods in detection of stent struts imaged in vivo by optical
coherence tomography (OCT) during percutaneous coronary interventions (PCI); (ii) to provide measurements for the assessment
and monitoring of in-stent restenosis by OCT post PCI. Thirty-nine OCT cross-sections from seven pullbacks from seven patients
presenting varying degrees of neointimal hyperplasia (NIH) are selected, and stent struts are detected. Stent and lumen boundaries
are reconstructed and one experienced observer analyzed the strut detection, the lumen and stent area measurements, as well
as the NIH thickness in comparison to manual tracing using the reviewing software provided by the OCT manufacturer (LightLab
Imaging, MA, USA). Very good agreements were found between the computer methods and the expert evaluations for lumen cross-section
area (mean difference = 0.11 ± 0.70 mm2; r
2 = 0.98, P < 0.0001) and the stent cross-section area (mean difference = 0.10 ± 1.28 mm2; r
2 = 0.85, P value < 0.0001). The average number of detected struts was 10.4 ± 2.9 per cross-section when the expert identified 10.5 ± 2.8
(r
2 = 0.78, P value < 0.0001). For the given patient dataset: lumen cross-sectional area was on the average (6.05 ± 1.87 mm2), stent cross-sectional area was (6.26 ± 1.63 mm2), maximum angle between struts was on the average (85.96 ± 54.23°), maximum, average, and minimum distance between the stent
and the lumen were (0.18 ± 0.13 mm), (0.08 ± 0.06 mm), and (0.01 ± 0.02 mm), respectively, and stent eccentricity was (0.80 ± 0.08).
Low variability between the expert and automatic method was observed in the computations of the most important parameters
assessing the degree of neointimal tissue growth in stents imaged by OCT pullbacks. After further extensive validation, the
presented methods might offer a robust automated tool that will improve the evaluation and follow-up monitoring of in-stent
restenosis in patients. 相似文献
73.
Segmentation of ultrasound images is a challenging problem due to speckle, which corrupts the image and can result in weak or missing image boundaries, poor signal to noise ratio and diminished contrast resolution. Speckle is a random interference pattern that is characterized by an asymmetric distribution as well as significant spatial correlation. These attributes of speckle are challenging to model in a segmentation approach, so many previous ultrasound segmentation methods simplify the problem by assuming that the speckle is white and/or Gaussian distributed. Unlike these methods, in this article we present an ultrasound-specific segmentation approach that addresses both the spatial correlation of the data as well as its intensity distribution. We first decorrelate the image and then apply a region-based active contour whose motion is derived from an appropriate parametric distribution for maximum likelihood image segmentation. We consider zero-mean complex Gaussian, Rayleigh, and Fisher-Tippett flows, which are designed to model fully formed speckle in the in-phase/quadrature (IQ), envelope detected, and display (log compressed) images, respectively. We present experimental results demonstrating the effectiveness of our method and compare the results with other parametric and nonparametric active contours. (E-mail:greg.slabaugh@gmail.com) 相似文献
74.
75.
Ido Somekh Benjamin Marquardt Yanshan Liu Meino Rohlfs Sebastian Hollizeck Musa Karakukcu Ekrem Unal Ebru Yilmaz Turkan Patiroglu Murat Cansever Shirly Frizinsky Vicktoria Vishnvenskia-Dai Erez Rechavi Tali Stauber Amos J. Simon Atar Lev Christoph Klein Daniel Kotlarz Raz Somech 《Journal of clinical immunology》2018,38(6):711-711
76.
In this work we review the indications for late preterm and early-term birth in uncomplicated dichorionic, monochorionic, and monoamniotic twin gestations. Uncomplicated dichorionic twins have optimal outcomes when delivered at 38 weeks' gestation. Monochorionic twins, however, are at greater risk for unexpected stillbirth, and a management plan of late preterm delivery (34-37 weeks) after informed consent is reasonable. Monoamniotic twins are at even greater risk for sudden intrauterine fetal demise, and it is recommended that these expectant mothers be managed by inpatient hospitalization with fetal testing 1-3 times per day and delivery between 32 and 34 weeks' gestation. Recommendations are also provided for the circumstance of single intrauterine fetal demise in a twin gestation. 相似文献
77.
Yigiter M Halici Z Odabasoglu F Keles ON Atalay F Unal B Salman AB 《European journal of obstetrics, gynecology, and reproductive biology》2011,157(1):94-100
Objective
To evaluate the effects of growth hormone (GH) as an antioxidant and tissue-protective agent and analyse the biochemical and histopathological changes in rat ovaries due to experimental ischemia and ischemia/reperfusion injury.Study design
Forty-eight adult female rats were randomly divided into eight groups. In Group 1, a period of bilateral ovarian ischemia was applied. In Groups 2 and 3, 1 and 2 mg/kg of GH was administered, and 30 min later, bilateral ovarian ischemia was applied (after a 3-h period of ischemia, both ovaries were surgically removed). Group 4 received a 3-h period of ischemia followed by 3 h of reperfusion. Groups 5 and 6 received 1 and 2 mg/kg of GH, respectively, 2.5 h after the induction of ischemia. At the end of a 3-h period of ischemia, bilateral vascular clips were removed, and 3 h of reperfusion continued. Group 7 received a sham operation plus 2 mg/kg of GH. Group 8 received a sham operation only. After the experiments, superoxide dismutase and myeloperoxidase activity and levels of glutathione and lipid peroxidation were determined, and histopathological changes were examined in all rat ovarian tissue.Results
Ischemia and ischemia/reperfusion decreased superoxide dismutase activity and glutathione levels in ovarian tissue, but increased lipid peroxidation levels and myeloperoxidase activity significantly in comparison to the sham group. The 1 and 2 mg/kg doses of GH before ischemia and ischemia/reperfusion decreased lipid peroxidation levels and myeloperoxidase activity in the experimental groups. The administration of GH before ischemia and ischemia/reperfusion treatments also increased superoxide dismutase and glutathione levels. The histopathological findings also suggested a protective role of GH in ischemia/reperfusion injury. That is, ovarian tissues in the ischemia groups showed histopathological changes, such as haemorrhage, cell degeneration, and necrotic and apoptotic cells, but these changes in the GH groups were lesser. Moreover, in the ischemia/reperfusion groups, acute inflammatory processes - such as neutrophil adhesion and migration, apoptotic and degenerative cells, stromal oedema and haemorrhage - were present. However, the ovarian tissues of the IR + GH (1 mg) group had minimal apoptotic cells, and the IR + GH (2 mg) group had no apoptotic cells. In addition, the general ovarian histological structures of these groups were similar to those of the healthy control group.Conclusions
The administration of GH is protective against ischemia and/or ischemia/reperfusion-induced ovarian damage. This protective effect can be attributed to the antioxidant properties of GH. 相似文献78.
Sema?Sezgin GoksuEmail author Seyda?Gunduz Dilek?Unal Mukremin?Uysal Deniz?Arslan Ali?M?Tatl? Hakan?Bozcuk Mustafa?Ozdogan Hasan?S?Coskun 《BMC palliative care》2014,13(1):51
Background
An increasing number of patients receive palliative chemotherapy near the end of life. The aim of this study is to evaluate the aggressiveness of chemotherapy in Turkish individuals near the end of life.Methods
Patients diagnosed with solid tumors and died from 2010 to 2011 in the medical oncology department of Akdeniz University were included in the study. Data about the diagnosis, treatment details and imaging procedures were collected.Results
Three hundred and seventy-three people with stage IV solid tumors died from 2010 to 2011 in our clinic. Eighty-nine patients (23.9%) patients underwent chemotherapy in the last month of life while 39 patients (10.5%) received chemotherapy in the last 14 days. The probability of undergoing chemotherapy in the last month of life was influenced by: age, ‘newly diagnosed’ patients, and performance status. There was no significant association of chemotherapy in the last month of life with gender and tumor type. Having a PET-CT scan did not alter the chemotherapy decision.Conclusion
In conclusion, chemotherapy used in the last month of life in a tertiary care center of Turkey is high. Increasing quality of life should be a priority near the end of life and physicians should consider ceasing chemotherapy and direct the patient to early palliative care.79.
Gürpinar OA Tuzlakoğlu K Onur MA Tümer A Serdar MA Unal N Pişkin E 《Journal of biomaterials science. Polymer edition》2003,14(6):589-600
In this study, attachment and growth of Baby Hamster Kidney (BHK) cells on ethylene diamine (EDA)-plasma-treated poly(L-lactide/epsilon-caprolactone) biodegradable copolymer films were investigated. The co-polymer (Mw: 58000; Mn: 35000 and PI 1.60) was synthesised by ring-opening polymerization of the respective dimers with using stannous octoate as the catalyst. The final ratio of L-lactide to epsilon-caprolactone obtained by 1H-NMR was 87:13. The co-polymer films were treated with the EDA-plasma in a glow-discharge apparatus. The BHK-30 cell line was cultured on plain and EDA-plasma-treated films and their pre-wetted forms (with ethanol and/or cell culture medium before use). Cell attachment and growth were followed. Alkaline phosphatase (ALP) activity and glucose uptake in cell culture medium were also investigated. There was no attachment in the first 12 h. Glow-discharge treatment increased significantly the attachment and growth. Pre-wetting with ethanol and cell culture medium was also increase significantly both the attachment and growth. 相似文献
80.
Esra Esim Buyukbayrak Ayse Yasemin Karageyim Karsidag Bulent Kars Onder Sakin Ayse Gul Ozyapi Alper Meltem Pirimoglu Orhan Unal Cem Turan 《Archives of gynecology and obstetrics》2011,283(3):581-584