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1.
目的 探讨在浅低温体外循环心脏跳动下完成小儿室间隔缺损修补术的可行性。方法 18例小儿室间隔缺损随机分为观察组和对照组 ,观察组在浅低温体外循环心跳下修补室间隔缺损 ,对照组为常规心脏停跳下修补室间缺损。测定心肌同功酶释放和三磷酸腺苷 ,观察左室压力 ,评价术野显露及气栓预防效果等。结果 观察组心肌同功酶释放明显低于对照组 ,三磷酸腺苷含量明显高于对照组 ,心肌超微结构基本正常 ,术中左室压力低于主动脉压力 ,术后无气栓发生。结论 浅低温体外循环心脏跳动下行小儿室间隔缺损修补术能更好地保护心肌。术野显露技术和防气栓的方法简便可行。 相似文献
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应用英国产“HYPOCOUNTGA”微量血糖测定仪(氧化酶光电比色法)对同期住院新生儿不分病种连续3天进行空腹血糖监测。结果在原发疾病情况下表现出低血糖发生频率高,而低血糖症状又被原发疾病所掩盖。在32例中足月儿23例,足月小样儿4例,早产儿5例,在32例96次监测中发现低血糖14例,其中足月儿9例,早产儿5例.发病率为43.7%;高血糖3例。无一例死亡。提示:新生儿患病情况下,易发生低血糖,其发生与疾病、孕周有关而与体重无关。因此,在新生儿期必须注意及时喂养与补充葡萄糖,防止低血糖时间过长对脑部造成损伤。 相似文献
5.
Weijiang Zhao Fang Yuan Guilin Li Zhongfang Shi Yun Cui Yazhuo Zhang Zhongcheng Wang 《中国神经再生研究》2007,2(5):276-280
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe.
OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats.
DESIGN: Observational contrast animal study.
SETTING: Beijing Neurosurgical Institute.
MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan.
METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin.
MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue.
RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES.
CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe. 相似文献
6.
我们研制了双硫腙化学修饰电极,并应用于人体中痕量铅的测定。由于该电极电解富集铅具有特效性,因而本法测铅有较高的灵敏度和较好的选择性。检出下限为2.5×10~(-10)mol/L(受空白所限)。实测人体样品,铅的回收率 SD为97.3±5.7%,变异系数CV为5.9%。 相似文献
7.
吸入麻醉药对人血浆和血小板血栓素B2生成与血小板聚集的影响 总被引:6,自引:0,他引:6
目的:探讨吸入麻醉剂氟烷、安氟醚和异氟醚对人血浆血栓素B2(TXB2),血小板TXB2生成与血小板聚集的影响。方法:血浆TXB2和血小板TXB2的生成量用放免分析法测量,血小板聚集率用比浊法测量。结果:吸入1MAC氟烷30分钟后,血浆TXB2浓度、二磷酸腺苷(ADP)和肾上腺素(E)诱导的血小板TXB2生成量与血小板聚集率显著下降,吸入1MAC安氟醚30分钟后,血浆TXB2浓度和血小板TXB2生成量与血小板聚集率亦显著下降,其降低的程度比氟烷轻。吸入1MAC异氟醚对上述指标无明显影响。血小板TXB2生成的减少与血小板聚集率的下降呈显著正相关。结论:氟烷显著抑制血小板聚集,安氟醚次之,异氟醚对血小板聚集无明显影响。其机制可能与氟烷和安氟醚通过抑制血小板上血栓素A2受体的亲和力,降低ADP和E诱导的血小板TXB2的生成有关。 相似文献
8.
胰岛素泵治疗与2型糖尿病第一时相分泌的研究进展 总被引:5,自引:0,他引:5
随着对糖尿病机理研究的深入,发现胰岛β细胞第一时相分泌,对糖尿病的发生、发展有重要影响,新诊断2型糖尿病患者早期予胰岛素泵治疗,模拟生理性胰岛素分泌方式,可改善第一时相分泌,促进胰岛β细胞功能的修复,利于糖尿病的治疗及预后。 相似文献
9.
Extended multilocus sequence typing system for Campylobacter coli, C. lari, C. upsaliensis, and C. helveticus 下载免费PDF全文
Miller WG On SL Wang G Fontanoz S Lastovica AJ Mandrell RE 《Journal of clinical microbiology》2005,43(5):2315-2329
A multilocus sequence typing (MLST) system has been reported previously for Campylobacter jejuni to both differentiate strains and identify clonal lineages. However, sequence variation at the MLST loci prevents its use for closely related Campylobacter species. We describe herein an expanded MLST method to include three clinically relevant Campylobacter species, C. coli, C. lari, and C. upsaliensis, and a fourth Campylobacter species, C. helveticus. The C. coli and C. helveticus methods use the same seven C. jejuni loci (aspA, atpA, glnA, gltA, glyA, pgm, and tkt); however, adk and pgi were substituted for aspA and gltA in C. lari and for gltA and pgm in C. upsaliensis. Multiple C. coli (n = 57), C. lari (n = 20), C. upsaliensis (n = 78), and C. helveticus (n = 9) isolates, representing both clinical and environmental sources, were typed. All four species were genetically diverse: the majority (> 80%) of the isolates had unique sequence types (STs). Using this method, mixed C. lari, C. upsaliensis, and C. helveticus isolates were identified; upon separation, each isolate was shown to contain two strains of the same species with distinct STs. Additionally, the expanded MLST method was able to detect potential lateral transfer events between C. jejuni and either C. coli or C. lari and between C. upsaliensis and C. helveticus. Thus, the expanded MLST method will prove useful in differentiating strains of five Campylobacter species, identifying mixed Campylobacter cultures, and detecting genetic exchange within the genus. 相似文献
10.
监护病室院内获得性败血症—常见致病菌株、危险因素及预后分析 总被引:1,自引:0,他引:1
目的:确定监护病室院内获得性败血症的发病率,致病菌的种类,对危重病患者预后的影响及诱发败血症的危险因素。方法:用单因素和多因素统计学方法确定败血症对危重患者预后的影响及诱发败血症的危险因素。结果:败血症在危重患者中有较高的发生率(8.07%)且致病菌以革兰氏阳性球菌为主。病死率亦较高(80.77%),单因素检验[OR=4.32,95%可信区间(CI)1.58-11.72]及多因素logistic回归分析(OR=4.97,1.21-20.37)均判定细菌性败血症显著影响危重病患者的病死率,此外,分析亦证实:监护病室血源性感染的发生与患者免疫功能低下,留置大静脉导管,气管切开,低白蛋白血症,感染发生前用过激素等因素密切相关。结论:败血症是监护病室常见并发症且对疾病预后有不利影响,应重视并针对其危险因素加以预防。 相似文献