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81.
Adenosine''s role in the genesis of bradyarrhythmias induced by acute myocardial hypoxia. 总被引:2,自引:0,他引:2
A close or even causal relation between myocardial adenosine and bradyarrhythmias during acute myocardial hypoxia was testified in guinea pig, rabbit and dog mainly by using specific competitive antagonist and synchronous quantitative analysis of 3 variables: intensity of myocardial hypoxia, degree of endogenous adenosine increment and severity of bradyarrhythmias. Results disclosed: A) striking resemblance of the bradyarrhythmias with hypoxic origin to those caused by exogenous adenosine, B) same locality of A-V conduction block induced by both myocardial hypoxia and exogenous adenosine, C) precise parallelism among the above-listed 3 variables with very high correlativity (r = 0.99, P < 0.01), D) frequent accompaniment of reversal of hypoxic bradyarrhythmias through resupply of 21% O2 with normalization of preexisted increase in myocardial adenosine, E) satisfactory blockade of hypoxic bradyarrhythmias by adenosine's specific antagonist--aminophylline and their augmentation by adenosine's uptake inhibitor--dipyridamole, F) close similarity of the characteristic curve representing relation among the above 3 variables to that among intensity of myocardial hypoxia, degree of endogenous adenosine increment and amount of coronary blood flow in which adenosine's role as a mediator has been well documented and G) reproducible persistence of bradyarrhythmias during myocardial hypoxia irrespective of preliminary vagotomy and atropinization, denoting independence of the occurrence of such dysarrhythmias upon vagal drive, suggestive of a mechanism other than vagotonia. We advocated that hypoxia-induced bradyarrhythmias was caused by increment in endogenous adenosine.
相似文献
82.
对11例手术病理证实的椎管内肿瘤进行磁共振成像(MRI)增强扫描的前、后分析,并对肿瘤定位、定性和鉴别诊断作了初步探讨。根据肿瘤形态、边界、强化程度,及与脊髓、硬脊膜、神经根等关系,MRI的增强扫描对提高其定位、定性诊断均有较大的帮助。 相似文献
83.
Peter J Koltai C Arturo Solares Jeffery A Koempel Keiko Hirose Tom I Abelson Paul R Krakovitz James Chan Meng Xu Edward J Mascha 《Otolaryngology--head and neck surgery》2003,129(5):532-538
OBJECTIVE: We sought to reintroduce a historical procedure-intracapsular tonsillar reduction (partial tonsillectomy or tonsillotomy)-for tonsillar hypertrophy causing obstructive sleep disordered breathing (OSDB) in children, as well as to determine whether partial tonsillectomy, compared with conventional (total) tonsillectomy when performed by more than one surgeon, is equally effective for the relief of OSDB while resulting in less pain and more rapid recovery. STUDY DESIGN: We conducted a retrospective case series at a tertiary children's hospital. The charts of children who underwent partial tonsillectomy and total tonsillectomy (1998 through 2002) for postoperative complications were reviewed. The caregivers were surveyed to assess postoperative pain, rapidity of recovery, and effectiveness of surgery for relieving symptoms of OSDB. RESULTS: Two hundred forty-three children underwent partial tonsillectomy and 107 children underwent total tonsillectomy. There were no significant differences in immediate and delayed complications between the groups. Both operations were equally effective in relieving OSDB. Children who had partial tonsillectomy had significantly less postoperative pain and significantly more rapid recovery. CONCLUSION: Intracapsular tonsillar reduction with an endoscopic microdebrider relieves OSDB as effectively as conventional tonsillectomy, but results in less postoperative pain and a more rapid recovery. 相似文献
84.
85.
叶内型肺隔离症致咯血的栓塞治疗 总被引:2,自引:0,他引:2
目的探讨叶内型肺隔离症患者咯血的栓塞治疗效果。方法结合文献复习,回顾性分析6例叶内型肺隔离症患者血管造影表现,并对畸形动脉行栓塞治疗。结果6例叶内型肺隔离症患者血管造影显示畸形动脉7支,表现为粗大、迂曲的体循环血管影;在毛细血管期可见隔离肺叶染色及引流静脉早显;静脉期显示引流静脉(肺静脉)。6例患者均进行畸形血管栓塞治疗,临床止血总有效率100%,随访1a均未复发。结论畸形血管栓塞术对叶内型肺隔离症致咯血的治疗,安全有效。 相似文献
86.
HPLC法测定七味清咽气雾剂中苦参碱的含量 总被引:2,自引:0,他引:2
目的:用HPLC测定七味清咽气雾荆中苦参碱的含量。方法:采用高效液相法,使用Shim-pack VP-ODS色谱柱,以乙腈珈.2%三乙胺溶液(1.4:98.6)用磷酸调至pH为2.5,柱温为55℃,流速为0.7mL/min,检测波长为214mn。结果:苦参碱在64.4~1030μg范围内呈良好的线性关系(r=0.9997),回收率为98.6%,RSD为0.9%。结论:方法灵敏、准确、专属性强,回收率高,重现性好,可作为七味清咽气雾剂的质量标准。 相似文献
87.
我院2000-2004年医院感染革兰阴性杆菌耐药性趋势的研究 总被引:1,自引:0,他引:1
[目的]了解2000年~2004年院内感染革兰阴性杆菌分布及其耐药性。[方法]主要使用MicroScan-4微生物鉴定及药敏仪对2000年1月~2004年12月引起院内感染革兰阴性杆菌进行鉴定及药物敏感试验,结果录入Whonet5.3软件进行分析、统计。[结果]5年间,革兰阴性杆菌所致医院感染中,大肠埃希菌比例最高,在32.8%~38.1%之间,阴沟肠杆菌、不动杆菌比例呈上升趋势。细菌的耐药率在逐年上升,其中阴沟肠杆菌和鲍曼不动杆菌,耐药性高于其它革兰阴性杆菌(P〈0.05),对第三代头孢菌素耐药率分别达到60%~80%、40%~70%。对亚胺培南耐药的菌株日益增多。[结论]细菌的耐药性逐渐增强,阴沟肠杆菌、鲍曼不动杆菌成为非常重要的医院感染病原菌,医务工作者要重视医院感染,加强耐药性监测,合理使用抗生素。 相似文献
88.
中医药干预治疗难治性肾病综合征研究进展 总被引:1,自引:0,他引:1
难治性肾病综合征(RNS),是指原发性肾病综合征经过强的松标准治疗无效者或经强的松的标准疗程治疗能缓解,但经常复发(1年内复发3次或半年内发作超过2次以上)者,约占原发性肾病综合征的39.9%-53.8%,目前西医常采用激素和细胞毒药物治疗,虽近期取得一定的疗效,但易复发并存在诸多副作用。鉴于此,临床医学研究者对中医药干预治疗难治性肾病综合症的研究越来越多,并积累大量的经验,本文就近5年来其有关文献综述如下。 相似文献
89.
99Tcm直接法标记血管抑素 总被引:4,自引:3,他引:1
目的: 探索用99Tcm直接标记血管抑素(angiostatin, AS)的方法,并研究标记产物的体外稳定性及其生物活性. 方法:制备的AS经鉴定后,分别用2-巯基乙醇(2-ME)和氯化亚锡(SnCl2)还原法进行标记,并用正交设计筛选最佳合成条件;对标记产物用纸层析法及Sephadex G-50层析柱分离测标记率;产物中分别加入牛血清白蛋白(BSA)、生理盐水及不同摩尔比的半胱氨酸(Cys)以观察其体外稳定性;用人脐静脉内皮细胞系ECV304观察其生物活性. 结果:2-ME法最佳标记条件为AS 100 μg,PB(0.5 mol*L-1, pH 7.3) 1 mL, 2-ME 100 μg, 亚甲基二膦酸盐(MDP)(用1 mL生理盐水溶解) 10 μL,加入99TcmO4- 185 MBq,标记率可达(97.0±1.5)%; SnCl2法为AS 100 μg,硼酸缓冲液(0.1 mol*L-1, pH 9.0) 1 mL, 20 g*L-1 SnCl2 (1 mol*L-1盐酸作为溶剂) 20 μL加入MDP药盒,用去氧水稀释至1 mL, 取20 μL,加入99TcmO4- 185 MBq,标记率可达(90.0±3.0)%. 产物在体外稳定;细胞培养观察其抑制内皮细胞生物活性与AS无显著差异. 结论:用99Tcm直接法标记AS简单高效,且对AS生物活性无明显影响. 相似文献
90.
犬海水中火器伤后早期血流动力学变化 总被引:3,自引:0,他引:3
Hui Meng Hong Shen Gao-wang Liu Tian-ling Zhu Jun-xin Zhang Zeng-rong Wu Hai-ji Bu 《第一军医大学学报》2004,24(5):493-496
OBJECTIVE: To investigate the hemodynamic changes in the early stages of gunshot wound of dogs in seawater for exploring early treatment protocol. METHOD: Fourteen conventional Beagles models undergoing gunshot wound in seawater were used along with another 2 dogs receiving the wound on land to serve as control. After the dogs were rescued from the seawater, the respiration (R), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), central venous pressure (CVP), pulmonary arterial wedge pressure (PAWP), and cardiac output (CO) were measured continuously in the early stages of the wound (53.62+/-12.19 min following injury), followed by statistical analysis of the results. RESULTS: Compared with the control group, the hemodynamic disturbance of the dogs receiving the wound in seawater was relatively severe during the first 15 min of the wound. The mortality tended to descend relevant to the position of the wounds, in the order of the head, chest, abdomen and limbs. CONCLUSIONS: Gunshot wound in seawater may cause severe hemodynamic changes, resulting in progressive dysfunction of circulation and high mortality rate. Early treatment should be targeted at hemodynamic stabilization in accordance to the characteristic changes during the early stages of the wound. 相似文献