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991.
992.
《International journal of oral and maxillofacial surgery》2014,43(9):1064-1068
The purpose of this paper is to present an innovative method for tongue reconstruction after cancer ablation using the medial sural artery perforator flap with the aid of preoperative computed tomography angiography (CTA) mapping. We describe the case of one patient treated with this technique and illustrate the anatomy of perforator vessels and the surgical techniques used in flap harvest. CTA was applied preoperatively to assess the number and location of medial sural artery perforators. The result obtained was both aesthetically and functionally satisfactory. The flap presented has the advantage of less donor site morbidity, and being thin, it is a suitable option for tongue reconstruction including that of a hemiglossectomy defect. CTA is an effective means of improving the safety of flap harvest. 相似文献
993.
994.
Andrew Holden Andrew A. Hill Brendan Buckley Brigid Connor David Semple Stephen Merrilees Emma Marsh Aws Alfahad Ram Iyer 《Journal of vascular and interventional radiology : JVIR》2019,30(1):61-68
Purpose
A prospective, single-center, single-arm feasibility study evaluated procedural and short-term performance of the Advance Enforcer 35 focal-force percutaneous transluminal angioplasty (PTA) balloon catheter in treating stenoses of mature native arteriovenous (AV) hemodialysis access circuits.Materials and Methods
Twenty-eight patients undergoing treatment for stenosis of a mature native AV hemodialysis access circuit were enrolled at a single institution. Angiographic assessments of the study lesion were required at baseline and after the procedure. Adjunctive procedures for significant residual stenosis were permitted, and patients had clinical and imaging follow-up for as long as 6 months.Results
Treatment with the study balloon was effective in reducing the average percent diameter stenosis of the treated lesion from 66.3% (range, 43.8%–93.3%) before the procedure to 23.7% (range, ?6.7% to 51.4%) after the procedure. The average inflation pressure required was 12.3 atm. Only 1 patient required an adjunctive procedure, and all patients could resume normal dialysis following the study procedure. At 3 months, 62.0% of study lesions remained patent, and the 6-month patency rate was 25.1%. Two adverse events associated with the study procedure were reported: access-site hematoma and forearm pain (3.6% each).Conclusions
The results demonstrate safety of the study balloon in treating AV access stenosis. Nominal-diameter angioplasty was achieved at relatively low pressure in most study patients without the use of adjunctive procedures, and resumption of normal dialysis was achieved for all patients. 相似文献995.
目的 提高对大面积脑梗死后出血性转化的CT诊断水平及新认识.方法 对60例大面积脑梗死后出血性转化的CT资料进行回顾性分析.结果 大面积脑梗死后复查头部CT,常规扫描37例,薄层扫描23例.出血性转化在梗死后1d检出3例,2~3 d检出16例,4~7 d检出9例,8~14 d检出32例.CT表现分3型:中心型(13例)、边缘型(21例)、混合型(26例).结论“出血性转化”已代替“出血性脑梗死”和“梗死后出血”,大面积脑梗死最易发生出血性转化,影像学检查是诊断出血性转化的金标准,CT为首选的主要检查方法,薄层扫描更利于病变早期检出,对指导临床选择治疗方案及预后判断具有重要意义. 相似文献
996.
ObjectiveThis study aimed to evaluate ocular vascularity in young adult migraine patients with visual aura and without visual aura.Material and MethodsThe study included 30 patients with migraine with visual aura (MWVA), 30 patients with migraine without visual aura (MWOVA), and 30 healthy control subjects, all between ages ≥18 and <45. Migraine patients were applied Headache Impact Test (HIT) and Migraine Disability Assessment Scale (MIDAS). Retinal nerve fiber layer thickness and ocular vascularity of all participants were evaluated with optical coherence tomography (OCT) and OCT angiography (OCTA).ResultsThe MWVA group had significantly lower superficial and deep foveal vascular density values compared to the control group (p = 0.039, p = 0.028, respectively). The foveal avascular zone was significantly enlarged in the MWVA group compared to the control group (p = 0.033). MWVA patients had significantly lower whole optic disc, optic disc inside, peripapillary, superior hemisphere, inferior hemisphere, superior quadrant, and temporal quadrant vascular density values compared to the control group (p < 0.05 all), while there was no significant difference in the nasal quadrant (p = 0.083). Migraine attack frequency, MIDAS, and HIT were negatively correlated with ocular vascular density values.ConclusionThe results of our study indicate that young adult patients with MWVA are at risk of decreased ocular vascularity and that this risk may increase with frequency and severity of migraine attacks. 相似文献
997.
The interactions of cancer cells within a solid mass with the surrounding reactive stroma are critical for growth and progression. The surrounding vasculature is recruited into the periphery of the growing tumour to supply cancer cells with nutrients and O2. This study focuses on developing a novel three-dimensional (3-D) in vitro biomimetic colorectal cancer model using colorectal cancer cells and connective tissue cells. The 3-D model comprises a dense artificial cancer mass, created by partial plastic compression of collagen type I containing HT29 colorectal cancer cells, nested in a non-dense collagen type I gel populated by fibroblasts and/or endothelial cells. HT29 cells within the dense mass proliferate slower than when cultured in a two-dimensional system. These cells form tumour spheroids which invade the surrounding matrix, away from the hypoxic conditions in the core of the construct, measured using real time O2 probes. This model is also characterized by the release of vascular endothelial growth factor (VEGF) by HT29 cells, mainly at the invading edge of the artificial cancer mass. This characterization is fundamental in establishing a reproducible, complex model that could be used to advance our understanding of cancer pathology and will facilitate therapeutic drug testing. 相似文献
998.
Atsushi Daimon Tomohito Tanaka Yuhei Kogata Yoshimichi Tanaka Daisuke Fujita Masahide Ohmichi 《Medicine》2021,100(10)
Introduction:Uterine fibroids, which are common benign tumors, rarely cause acute complications. We herein report a case of hemoperitoneum associated with uterine fibroid that could be diagnosed preoperatively with contrast-enhanced computerized tomography (CT).Patient concerns:A 48-year-old woman with uterine fibroid developed extremely severe lower abdominal pain on the first day of her menstrual period.Diagnosis:Ultrasonography and contrast-enhanced CT revealed a uterine fibroid and extravasation from the dilated vessels of the uterine fibroid.Intervention:Emergent abdominal hysterectomy was performed.Outcomes:The total amount of bleeding was 4,600 mL. Intraoperative blood salvage (1,357 mL), 6 units of red blood cells, 4 units of fresh frozen plasma, and 20 units of platelet concentrates were transfused. The postoperative course was uneventful. Pathological examination confirmed a benign uterine fibroid.Conclusion:CT could be useful to determine a diagnosis for bleeding from ruptured subserosal uterine fibroid. 相似文献
999.
Bowei Yuan Xue Jiang Yan Liu Jie Dong Dongmei Li 《Journal of cranio-maxillo-facial surgery》2021,49(3):206-214
Congenital microphthalmia is a rare phenotype characterized by eye growth retardation. Due to the lack of eyeball stimulation, children suffering from congenital microphthalmia always have bony orbital maldevelopment, which leads to facial asymmetry. In the present study, a structured light 3D scanning system was used as a novel method to measure the three-dimensional periorbital asymmetry in children with congenital microphthalmia.Children with unilateral congenital microphthalmia of 0–6 years old were enrolled in the present study. All participants underwent an ultrasound scan to measure the axial length, and accepted the structured light 3D scanning system for their periorbital appearance. The degree of periorbital asymmetry was evaluated using 17 facial landmarks within a three-dimensional cartesian coordinate system (the X-axis represented the horizontal direction, the Y-axis represented the vertical direction, and the Z-axis represented the sagittal direction). Paired student t-test and ANOVA were used in the present study. A three-dimensional periorbital topography was also established to further illustrate the periorbital asymmetry.A total of 67 children were recruited, which included 31 boys and 34 girls. The axial length on the affected side (12.28 ± 3.35 mm) was generally smaller than that on the unaffected side (20.54 ± 1.65 mm, P < 0.001). When grouped by age, the periorbital asymmetry mainly manifested in the Y-axis and Z-axis directions. The unaffected side had a higher orbitale superior (5.09 ± 0.35 vs. 3.02 ± 0.30, P < 0.001) and a lower orbitale inferior (?19.52 ± 0.51 vs. ?16.90 ± 0.53, P < 0.001) in 0–1 year old group. Same performances were also found in the 1–3 and 3–6 age groups. When grouped according to the proportion of axial length on the bilateral sides, seven of the 12 Y-values and all 12 Z-values had statistical differences.The structured Light 3D scanning system may serve as a beneficial complementary tool for computed tomography, in order to better understand the periorbital deformities caused by congenital microphthalmia. 相似文献
1000.
L. Chandler K.E. Park O. Allam M.A. Mozaffari S. Khetpal J. Smetona N. Pourtaheri X. Lu J.A. Persing M. Alperovich 《International journal of oral and maxillofacial surgery》2021,50(8):1040-1046
The decision about which metopic synostosis patients should undergo surgery remains controversial. Multiple measures for radiographic severity have been developed in order to determine the optimal criteria for treatment. The aim of this study was to perform an extensive craniomorphometric analysis of patients who underwent surgery for metopic synostosis to validate and compare the various severity scales developed for this non-syndromic craniosynostosis. A comparative morphometric analysis was performed using computed tomography scans of preoperative metopic synostosis patients (n = 167) and normal controls (n = 44). Measurements included previous and newly developed metopic severity indices. Volumetric and area analyses were used to determine the degree of anterior cranial area and potential volume restrictions. Of the severity indices measured, the frontal angle, endocranial bifrontal angle (EBF), adjusted EBF (aEBF), anterior cranial fossa angle, horizontal cone angle, and bitemporal/biparietal distance ratio were significantly different in the metopic subjects relative to controls overall. However, metopic index, orbital rim angle, foramen ovale distance, and cranial volume exhibited no significant difference from controls. Only the frontal angle and aEBF correlated with the changes in anterior cranial dimensions observed in metopic synostosis. In conclusion, the frontal angle and aEBF provide the most accurate measures of severity in metopic synostosis. 相似文献