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121.
We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient.  相似文献   
122.
Patch clamp techniques were used to study whole cell ionic currents in Schwann cells (SC) from a tropical marine fish, the bicolor damselfish, Pomacentrus partitus. The bicolor damselfish is affected by a disease termed damselfish neurofibromatosis (DNF), being developed as an animal model of neurofibromatosis-type 1 (NF1) in humans. NF1 affects SC, fibroblasts, and perineurial cells. The sole depolarization-activated ionic current present in cultured SC from normal fish peripheral nerve and from neurofibromas of fish with induced or spontaneously occurring DNF was an inactivating K+ current (K current), with a strong dependence on the Nernst potential for K+. This K current activated at depolarizations to -40 mV and above and inactivated during a maintained test pulse (0.2-1 s), but inactivation was significantly greater in tumored SC. Both currents were inhibited by 4-aminopyridine (Kd ? 1 mM) and by dendrotoxin (15 μM) but were insensitive to extracellular tetraethyammonium (≤ 150 mM), indicating that the whole cell currents were similar pharmacologically. The currents could be distinguished on the basis of their sensitivity to depolarized holding potential, with normal cells less sensitive. Half-inactivation of the current was -32 mV in normal cells and -38 mV in tumored cells. Inactivation curves constructed from the average normalized current for many SC were significantly different in normal and tumored cells. When the depolarized holding potential was maintained between test depolarizations, greater voltage-dependent inactivation in tumored cells was apparent. Normal cells maintained an average of 36% of peak current at a holding voltage of ?40 mV, while in tumored cells this average was 12%, a significant difference. © 1994 Wiley-Liss, Inc.  相似文献   
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124.
目的:探讨胃肠道基质细胞瘤的临床诊断、治疗和预后。 方法:回顾性分析1995—2005年收治的31例胃肠道基质细胞瘤临床和病理资料。结果:根据Fletcher风险分级,极低风险3例,低风险5例,中风险15例,高风险8例。CD117,CD34,desmin,SMA,S-100蛋白阳性表达率分别为93.5%,87.1%,38.7%,35.5%,25.8%,其阳性表达率与肿瘤危险程度无关(χ2=0.35,0.12,0.03,0.05,0.01,均P>0.05)。肿瘤是否浸润黏膜肌层或浆膜层与肿瘤危险程度相关(χ2=4.87,P<0.05)。结论:用Fletcher分级对胃肠道基质瘤分级评价更为科学合理。中、高危险程度者复发率26.0%,明显高于极低和低风险者(P<0.001)。根治性手术是治疗胃肠道基质瘤最佳选择。肿瘤浸润黏膜肌层或浆膜层是危险的重要指标。核分裂相是判断预后的独立预后因素。  相似文献   
125.
目的:探讨2型糖尿病肾病患者血清肿瘤坏死因子仅(TNF-α)、一氧化氮(NO)和内皮素(ET)的水平变化及其临床意义。方法:用ELISA法检测91例2型糖尿病患者血清TNF-α水平,NO与ET的水平分别用硝酸还原酶法和放射免疫法测定。结果:2型糖尿病肾病各组患者TNF-α和ET水平较对照组明显升高,其中ODN组最高(P〈0.01)。而2型糖尿病肾病各组患者血清NO水平较对照组明显减少(P〈0.01)。显性糖尿病肾病患者血清TNF-α和ET呈正相关;血清TNF-α和NO、ET和NO均成负相关。结论:TNF-α、NO与ET可能参与2型糖尿病肾病的发病及病程变化过程,检测患者TNF-α、NO与ET水平可作为判断预后、指导治疗的指标。  相似文献   
126.
目的探讨^188Re—Herceptin-磁性纳米微粒在外置磁场下对HER-2/neu癌基因高表达的SKBR-3乳腺癌细胞的靶向结合性及抗癌作用。方法采用戊二醛交联法使人源性单克隆抗体Her—ceptin与磁性纳米微粒交联,用直接标记法制备^188Re—Herceptin及^188Re—Herceptin-磁性纳米微粒,用羰基铼标记法制备^188Re-磁性纳米微粒。肿瘤细胞体外抑制实验设4个组:^188Re—Herceptin-磁性纳米微粒组、^188Re—Herceptin组、^188Re-磁性纳米微粒组和^188ReO4^-组,各组均设3.7×10^4、18.5×10^4、37×10^4、55.5×10^4、74×10^4Bq/ml5个放射性剂量级别;另设生理盐水对照组。采用四甲基偶氮唑蓝(MTT)法测定各组的抑瘤效应,计算相对抑制率,采用半数抑制放射性浓度(IC50)对各组抑瘤作用进行比较和评价。结果^188Re—Herceptin-磁性纳米微粒和^188Re—Herceptin组对SKBR-3细胞均有较强杀伤作用,且呈剂量依赖性;而^188Re-磁性纳米微粒和^188Re04组的杀伤作用较弱0188Re—Herceptin-磁性纳米微粒组的IC50(53.1×10^4Bq/L)明显低于^188Re—Herceptin组(76.1×10^4Bq/L);^188Re一磁性纳米微粒组和^188ReO4组的IC50分别为169×10^4和175×10^4Bq/L,明显高于前2组。结论^188Re—Herceptin-磁性纳米微粒和^188Re—Herceptin均可明显抑制体外培养的SKBR-3乳腺癌细胞增殖,且前者的抑制作用较后者强。  相似文献   
127.
目的研究蟾酥注射液对小鼠移植性肿瘤 S180和人结肠癌 HT-29裸鼠移植性肿瘤的抑制作用.方法分别用小鼠 S180和人结肠癌 HT-29裸鼠两种荷瘤小鼠模型,观察药物对上述肿瘤的抑瘤作用,并镜下观察后者细胞凋亡情况.结果与荷瘤阴性对照组比较,蟾酥注射液各剂量组对小鼠 S180抑瘤率( IR)为 19.1%~38.2%(P<0.05),呈量效关系;而对人结肠癌 HT-29裸鼠移植性肿瘤的 IR为 9.5%~15.8%(P>0.05),也呈量效关系,但差异均未见统计学意义;环磷酰胺则能显著抑制小鼠 S180和 HT-29细胞裸鼠移植性肿瘤的生长( IR分别为70.7%和 67.1%, P<0.01),镜检可见其有显著促进肿瘤细胞凋亡作用;未发现实验药物出现明显的毒副作用.结论该实验所用的蟾酥注射液,对小鼠 S180有抑制作用,而对人结肠癌 HT-29裸鼠移植性肿瘤,则作用不明显,表明不同类型的肿瘤对其敏感性不同.  相似文献   
128.
年龄小于45岁原发性慢性闭角型青光眼的显微手术治疗   总被引:1,自引:0,他引:1  
目的探讨原发性慢性闭角型青光眼年轻患者临床治疗的经验和体会。方法对临床收治的41例52眼、年龄〈45岁、临床确诊为进展期或晚期原发性慢性闭角型青光眼的病例进行抗青光眼显微手术处理的病例进行回顾性分析。结果随访时间平均(32.50±5.08)个月;男16例,女25例;进展期28眼,晚期24眼;52眼均行抗青光眼手术-复合式小梁切除手术治疗;眼轴长平均(22.40±1.63)mm,其中〈21mm占17.31%,小眼球占13.46%;前房深度平均(1.90±0.39)mm,其中〈1.9mm占61.46%;超声生物显微镜检查高褶虹膜构型占59.62%,其中睫状突位置靠前者10眼;术前平均眼压(41.73±12.26)mmHg,末次术后平均眼压(12.03±4.57)mmHg,术前后眼压差异有统计学意义(t=3.520,P〈0.001)。术后并发症主要有浅前房,恶性青光眼。恶性青光眼手术处理方式包括玻璃体抽液、前段玻璃体切割以及超声乳化白内障吸除加人工晶状体植入术治疗。4眼因眼压控制不理想,行二次抗青光眼手术治疗。结论年轻原发性慢性闭角型青光眼患者,女性多见,多伴有眼轴短、前房浅等特点,抗青光眼复合式小梁手术治疗要注意防治术后浅前房、恶性青光眼的发生。术前详细检查、手术操作精细以及有效处理术后并发症将有助于提高手术成功率和减少并发症。  相似文献   
129.
李荣 《安徽医学》2005,26(3):206-207
目的探讨绝经后阴道出血的病因及相关因素。方法对129例绝经后阴道出血患者的临床资料进行回顾性分析。结果因良性疾病引起的出血占51.16%,非器质性疾病占25.58%,恶性肿瘤占23.26%,患者出血时年龄大,绝经年限长恶性肿瘤发生率高。结论绝经后阴道出血的主要原因是良性疾病和非器质性病变,但恶性肿瘤仍占一定比例。因此对绝经后阴道出血患者应采取综合的检查手段,明确病因,对因治疗。  相似文献   
130.
Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect.  相似文献   
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