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41.
Jhoji Tanabe Hirohiko Nakazato Hisayoshi Tanabe Hidetoshi Hanasaki Kazuo Kawasaki Daizo Yonemura 《Documenta ophthalmologica. Advances in ophthalmology》1986,63(2):165-171
The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans. 相似文献
42.
耳源性脑疝25例,抢救成功者19例。采用单纯脑脓肿穿刺抽脓抢救脑疝6例,仅1例成功;开颅减压术抢救脑疝20例,18例抢救成功。本组临床实践和文献报道都说明耳源性脑疝一旦发生应即刻行开颅减压术,能卓有成效地抢救生命 相似文献
43.
Introduction Hypothalamic hamartomas are congenital malformations. Clinically, they can be asymptomatic, but they cause seizures, mental
retardation and precocious puberty in many cases.
Case report A 20-day-old boy with hypothalamic hamartoma and bilateral anophthalmia was presented. Except those, no other congenital anomaly
was detected.
Conclusion This is a rare case of hypothalamic hamartoma with bilateral anophthalmia. The mutations at SOX2 has an important role in
the developing brain and eyes. 相似文献
44.
目的观察神经干细胞经脑室注射后在损伤脊髓的早期动态变化。方法取转录有绿色荧光蛋白(GFP)基因的孕16天SD鼠胚脑海马组织,培养成神经干细胞球,注射到损伤脊髓鼠第四脑室(实验组),观察其在脊髓的存活、分化状况。结果移植细胞在脊髓表面形成细胞团。分布于损伤区头侧。细胞团的面积背侧小于腹侧;数目背侧多于腹侧。这种分布和增殖形式见于损伤脊髓正常部分和无损伤脊髓(对照组)。1周时细胞侵入损伤区,GFAP表达呈阳性。2~3周时与宿主细胞良好整合。结论移植细胞通过脑脊液能广泛分布于脊髓表面。保持黏附、增殖和分化能力。并可迁移、整合到损伤脊髓组织中。 相似文献
45.
Kalai Arasu Muthusamy Vicknes Waran Savithri D. Puthucheary 《Journal of clinical neuroscience》2007,14(12):1213-1215
Burkholderia pseudomallei infection of the central nervous system (CNS) is rare with less than 50 cases reported over the last 30 years. The retrospective melioidosis study at University Malaya Medical Centre has documented three cases of CNS melioidosis out of more than 160 cases of melioidosis since 1978. There were two patients with brain abscess and one with spinal epidural abscess. The predisposing factors were: one patient was an aboriginal farmer and the other two were diabetic. Their age ranged from 17 to 45 years. Prominent neurological features were limb weakness, cranial nerve palsy (6th and 7th) and visual disturbance. CT brain scan and MRI spine showed abscess formation, subdural collection, and spinal epidural collection, osteomyelitis of vertebra and occipital bone and also sagital sinus thrombosis. All these patients underwent surgical drainage leading to bacteriological diagnosis as well as appropriate long-term antibiotic therapy. All had good recovery at 6 months after completion of treatment. 相似文献
46.
动态增强MR灌注成像在脑胶质瘤诊断中的价值 总被引:1,自引:0,他引:1
目的 探讨动态增强T2 WMR灌注成像在脑胶质瘤术前分级预测及鉴别诊断中的价值。资料与方法 有病理或追踪结果的 4 8例脑病变患者 ,其中胶质瘤 2 5例 (高、低级别胶质瘤分别为 16例和 9例 ) ,非胶质瘤病变 2 3例。全部病例均行常规T1WI、T2 WI和EPI SE序列动态增强MR灌注成像。计算每个病灶的最大相对脑血容量 (rCBV)比值 (病灶最大rCBV/对侧正常脑白质rCBV)。分析胶质瘤的最大rCBV比值与其组织学级别的关系 ,并比较胶质瘤与非胶质瘤的灌注异常及常规MRI强化表现。结果 高级别胶质瘤 ( 16例 )的最大rCBV比值为4 .6 0± 1.98( 2 .5 5~ 9.2 2 ) ,低级别胶质瘤 ( 9例 )的最大rCBV比值为 1.86± 1.5 2 ( 0 .85~ 5 .72 ) ,经t检验 ,两组之间有显著统计学差异 (P <0 .0 1)。脑膜瘤、转移瘤、血管母细胞瘤、淋巴瘤均显示有局部高灌注 ,最大rCBV比值为5 .35± 2 .39( 3.15~ 12 .39) ,而有强化表现的脑梗死、脑炎性灶及放射性脑损伤表现为低、等灌注 ,最大rCBV比值为1.2 7± 0 .36 ( 0 .85~ 1.72 )。结论 MR灌注成像在胶质瘤的术前影像学分级预测上有重要价值 ,在脑胶质瘤的某些鉴别诊断上亦具有一定的参考价值 相似文献
47.
Roberto Rivera-Luna Marta Zapata-Tarrés Aurora Medina-Sansón Enrique López-Aguilar Ana Niembro-Zúñiga J. Amador Zarco Alfonso Marhx-Bracho Fernando Rueda-Franco Leticia Bornstein-Quevedo 《Child's nervous system》2007,23(5):543-547
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of
age diagnosed with low-grade astrocytoma.
Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three
patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection
and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy.
Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial
group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008).
Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the
outcome. 相似文献
48.
49.
目的通过对国人脑池显微解剖的研究,以指导显微神经外科手术和进一步理解影像学解剖的重要临床意义和应用价值。方法对15具经福尔马林固定的国人成年头颅标本的颅内各个脑池进行显微解剖研究,测量和描述各脑池的位置、大小、形态及结构。结果颅内重要的脑池有(1)嗅池:长度为(32.68±2.97)mm,宽度为(7.18±1.82)mm,深度为(7.20±1.27)mm;(2)视交叉池:侧壁长度为(14.88±3.07)mm,上表面前壁长(14.20±1.47)mm,后壁长(10.37±1.59)mm;(3)颈内动脉池:长度为(15.06±3.07)mm,宽度为(12.01±1.32)mm;(4)终板池:底边左侧长度为(8.99±1.15)mm,右侧长度为(21.00±1.09)mm,最大宽径为(16.42±2.58)mm;(5)脚间池:最大深度为(19.47±2.28)mm,池顶宽度为(11.35±2.85)mm;(6)脚池:为三角形,三边长度分别为(10.48±2.56)mm,(9.64±1.78)mm,(3.58±0.25)mm;(7)外侧裂池:上部长度为(18.63±2.02)mm,基底部长度为(38.08±3.22)mm,宽度为(5.65±0.92)mm,深度为(7.02±2.28)mm;(8)胼胝体池:平均最大宽径为(3.44±0.40)mm;(9)四叠体池:最大长径为(19.37±3.38)mm,最大宽径为(15.24±2.37)mm,最大前后径为(3.65±0.57)mm;(10)环池:为环形,最大宽度为(3.16±0.37)mm;(11)小脑延髓池:最大长度为(18.77±1.77)mm,最大宽度为(32.4 相似文献
50.
A. R. Mridha M. C. Sharma C. Sarkar V. Suri A. Rishi A. Garg A. Suri 《Child's nervous system》2007,23(10):1209-1213
Introduction Myxopapillary ependymomas are low grade tumours that are known to recur locally even after complete excision, but metastasis
to distant sites is extremely uncommon.
Case report We report an unusual case of lumbo-sacral myxopapillary ependymoma in a 13-year-old boy with metastasis to both cerebellopontine
angles. To the best of our knowledge, this is the youngest patient of metastatic myxopapillary ependymoma. 相似文献