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991.
目的:胃癌发生发展的分子基础仍不甚明了,为了明确H—ras点突变在胃癌发生发展中的作用,本研究对胃癌组织H—ras点突变进行检测。方法:采用多聚酶链延伸反应—限制性片段长度多态性分析法(PCR—RFLP)对88例福尔马林液固定、石蜡包埋胃癌组织H—ras第12位和61位密码子点突变作了检测,并对点突变与肿瘤生物学行为及预后的关系进行分析。结果:H—ras总突变率为14.8%(13/88),点突变的发生与肿瘤将膜浸润,淋巴结转移、临床分期及术后生存期密切相关。结论:检测胃癌组织H—ras基因点突变有助于判断胃癌患者的预后。  相似文献   
992.
993.
Shen R  Xu CG  Li LZ  Zhang T  Qin XM  Li J 《中华内科杂志》2003,42(12):857-860
目的 研究骨髓增生异常综合征 (MDS)外周血CD+ 4 、CD+ 8T细胞早期激活标志CD69的表达及血清、骨髓可溶性肿瘤坏死因子受体 1、2 (sTNF R1、2 )的水平及其意义。方法 在植物血凝素 (PHA) 2 0mg/L条件下进行全血细胞培养 ,于 0h和 4h分别用流式细胞仪对CD+ 4 、CD+ 8T细胞CD69的表达进行分析。用ELISA法检测血清和骨髓sTNF R1、2的水平。结果 PHA刺激前难治性贫血 (RA)与难治性贫血伴环形铁粒幼细胞增多 (RAS)CD+ 4 、CD+ 8细胞CD69的表达率分别为 8 32 %、9 88% ,难治性贫血伴原始细胞增多 (RAEB)与转变中的RAEB(RAEB T)CD+ 8细胞CD69的表达率为7 92 %。PHA刺激后MDS患者CD+ 4 、CD+ 8细胞表达CD69明显增强 ,RA +RAS为 5 3 4 6 %、5 1 6 3% ;RAEB +RAEB T为 4 2 93%、4 1 96 % ,CD+ 4 与CD+ 8细胞CD69的表达率相似。MDS两种sTNF R1水平均明显升高 ,RA +RAS组sTNF R1血清为 (1 5 8± 0 6 8) μg/L ,骨髓为 (2 10± 0 2 6 ) μg/L ;sTNF R2血清为 (1 4 1± 0 5 0 ) μg/L ,骨髓为 (1 95± 0 6 4 ) μg/L ;RAEB +RAEB T组sTNF R1血清为 (2 6 2± 2 5 5 ) μg/L ,骨髓为 (3 12± 0 6 7) μg/L ;sTNF R2血清为 (1 96± 0 5 6 ) μg/L ,骨髓为(3 0 9± 0 6 2 ) μg/L。血清sTNF R2水平与PHA刺激  相似文献   
994.
沉默型动脉导管未闭的血流动力学特征及治疗探讨   总被引:2,自引:0,他引:2  
目的 探讨沉默型动脉导管未闭 (patentductusarteriosus ,PDA)的血流动力学特征及治疗。方法 对临床结合超声心动图诊断的 7例沉默型PDA病人进行心导管检查 ,术后 3个月、6个月及每年随访一次。结果  7例病人肺动脉平均压平均为 (16 0± 2 4 )mmHg ,肺循环和体循环血流量比 (Qp/Qs)为 1 0 8± 0 0 2 ,左向右分流量平均为 (0 32± 0 0 8)L/min ,左向右分流量占肺循环血流量比例平均为 0 0 98± 0 0 2 4。PDA最窄处平均直径为 (0 9± 0 2 )mm。 7例病人均未行外科手术和介入治疗。平均随访 9 5个月 (临床、心电图、超声心动图 ) ,未发现房室腔增大、肺动脉压增高 ,无感染性动脉内膜炎和心内膜炎发生。结论 沉默型PDA的左向右分流量很少 ,对病人的血流动力学影响小。沉默型PDA病人是否需要治疗尚无定论。  相似文献   
995.
AIM To find out the difference of human primary liver carcinogenesis between Han and minority ethnic patients in Xinjiang.METHODS Expression of p53, c-erbB-2, Hrssp21 protein and proliferating cell nuclear antigen (PCNA) in tumor tissues of 50 patients (Han 38, minority 12 ) with primary hepatic carcinoma was detected by immunohistochemistry (LSAB). RESULTS The positive frequency of p53, cerbB-2, H-rasp21 and PCNA expression was 46.0% (23/50), 70.0% (35/50), 68.0% (34/50)and 82.0% (41/50) in tumor tissues; 4.0% (2/50), 22.0% (11/50), 64.0% (32/50) and 52.0%(26/ 50 ) in peritumors respectively and a significant difference, except for H-rasp21, of oncogene alteration was found (P<0.05)between tumor and non- tumorous tissues.Combined the three oncogenes alteration, 26%(13/50)tumor tissues had positive immunoreactivity, but in peritumor and normal livers it was negative. The positive rate of p53,c-erbB-2 and H-rasp21 protein expression was 39.5% (15/38), 60.5% (23/38) and 39.5% (15/38) in tumors of Han patients; 66.7% (8/12),100% (12/12) and 75.0% (9/12) in minorities respectively, with statistical difference (P<0.05). CONCLUSION Overexpression of p53, c-erbB-2 and H-rasp21 in human primary liver carcinoma is an important biomarker of genetic alteration.The different frequency of these oncogenetic changes may reflect some environmental or/and ethnic hereditary factors affecting the liver carcinogenesis. The special life style of Han,Uygur, Kazak and Mongolia nationalities in Xinjiang may also be related to the etiopathogenesis of this disease.  相似文献   
996.
目的:比较不同效应室浓度的舒芬太尼靶控输注对非体外循环冠状动脉旁路移植术(OPCAB)患者麻醉效果的影响。方法:42例择期OPCAB的患者随机分为3组,分别在术中使用0.4ng/mL(组Ⅰ)、0.6ng/mL(组Ⅱ)和0.8ng/mL(组Ⅲ)固定效应室浓度的舒芬太尼靶控静脉麻醉。观察患者术中血流动力学及脑电双频普指数(BIS)值,记录术中舒芬太尼、丙泊酚、多巴胺用量,术后恢复时间及围手术期心肌酶谱[肌酸激酶(CK)与肌酸激酶同工酶(CK-MB)]。结果:3组患者术中都能维持满意的血流动力学。术中丙泊酚、多巴胺的用量,术后恢复时间和围手术期心肌酶谱差异无显著性(P>0.05)。但Ⅱ组与Ⅲ组患者舒芬太尼用量多于Ⅰ组(P<0.01),Ⅲ组患者心脏指数(CI)在手术开始时低于Ⅰ组(P<0.05),心率(HR)自搭桥开始后增快(与搭桥前比较P<0.01),Ⅰ组患者术中BIS值高于Ⅱ组与Ⅲ组(P<0.05)。结论:采用0.4ng/mL、0.6ng/mL或0.8ng/mL固定效应室浓度的舒芬太尼靶控静脉麻醉对OPCAB患者术中均可以维持满意的血流动力学,但0.6ng/mL为最合适的靶控浓度。  相似文献   
997.
OBJECTIVE: Hereditary non‐polyposis colorectal cancer (HNPCC) syndrome is the most common cause of hereditary colorectal cancer with an early age of onset. Microsatellite instability (MSI) and germline mutation in one of the DNA mismatch repair (MMR) genes are found in the majority of HNPCC families and provide an opportunity for genetic diagnosis and prophylactic screening. The MMR gene mutation spectrum may vary across different populations and be influenced by founder mutations that prevail in specific ethnic groups. China is a big and ancient nation with enormous genetic diversity, which is especially notable between the northern and southern Chinese populations. A MMR gene mutation database for the southern Chinese population based in Hong Kong has been previously established. This study compares the MMR gene mutation spectrum and the MSI of HNPCC between the northern and southern Chinese populations. METHODS: Twenty‐five HNPCC families from northern China were systematically analyzed. The MSI analysis was performed using five loci in the USA National Cancer Institute (NCI) panel (D2S123, D5S346, BAT‐25, BAT‐26 and BAT‐40) by PCR from the tumor and normal tissue. MSH2, MSH6 and MLH1 were performed using immunohistochemical staining. Two founder mutations of MSH2 and MLH1 were examined by PCR base analyses using primers flanking the two deletion sites (c.1452_1455delAATG in MSH2 and 1.8 kb deletion involving exon 11 of MLH1) . RESULTS: Of the 25 families collected, 19 met Bethesda guideline (BG) 1 and six met BG3. Twenty‐two (15.7%) were extra‐colonic cancers with gastric cancer (in seven patients) being the most common cancer type. Of the 25 tumors analyzed, 21 (84%) were high level microsatellite instability (MSI‐H) and four (16%) were microsatellite stable (MSS). Eighteen (86%) of the 21 MSI‐H tumors showed loss of either the MLH1 or the MSH2 protein. Three MSI‐H tumors and all four MSS tumors showed no loss of expression of the three MMR proteins. Out of the 21 patients with MSI‐H tumors, 12 (57%) showed pathogenic germline mutations in either MLH1 (n = 8) or MSH2 (n = 4). Overall, three novel mutations (in patients H22, H17 and H29) have been identified. One of them, c.503_4insA, caused a frameshift mutation in the MLH1 gene. The other two were found in the MSH2 gene, including a frameshift (c.899_890insAT) and a splice junction (IVS7‐1G→A, SA of Exon 8) mutation. CONCLUSIONS: The results suggest a distinctly different mutation spectrum of MMR genes between northern and southern Chinese populations and call for a systematic, nationwide study to facilitate the design of a MMR gene mutation detection strategy tailored for individual populations in China.  相似文献   
998.
目的:前瞻性对照研究比较两种静脉用铁剂治疗维持性血液透析(MHD)患者肾性贫血的疗效及不良反应。方法:全国十家医院血液透析中心共210例MHD患者入组,随机分成蔗糖铁组(n=105)和右旋糖酐铁组(n=105)。两组均静脉滴注铁剂100mg/次,每周两次,总量1000mg。观察期共8周,治疗期间每隔两周取静脉血检测血红蛋白(Hb)、红细胞压积(Hct)、铁蛋白(SF)、转铁蛋白饱和度(TSAT)等指标。结果:(1)两组患者治疗前的年龄、性别构成、体重、透析龄、治疗前的促红细胞生成素(EPO)剂量无明显差异;(2)治疗第四周后两组患者的Hb、Hct、SF及TSAT均明显升高,两组相比,无明显差异。(3)两组均未发生不良反应。结论:蔗糖铁与右旋糖酐铁静脉使用纠正肾性贫血的疗效相同,无明显不良反应。  相似文献   
999.
INTRODUCTION: liver cirrhosis is the main cause of portal thrombosis (PT), while hypercoagulability syndromes are rarely found as the etiology of PT. We report a case of portal and mesenteric thrombosis secondary to protein S deficiency. CASE REPORT: a 74-year-old woman was admitted with melena secondary to upper gastrointestinal bleeding. She reported mild, diffuse abdominal pain in the last 2 weeks. Endoscopy revealed ruptured esophageal varices. Doppler ultrasonography and CT demonstrated a heterogeneous liver, splenomegaly and ascites, and complete non-occlusive PT involving the hilum and portal branches, as well as the superior mesenteric vein, with portosystemic collaterals. At this point a complete study for cirrhosis etiologies was negative, including a liver biopsy that showed nonspecific architectural changes secondary to diminished blood flow, which suggested non-cirrhotic portal hypertension. The search for hypercoagulability states determined a deficiency of S protein, with total pS = 107% and free pS = 56%. The patient was started on anticoagulant treatment and no other thrombotic events occurred. DISCUSSION: PT usually manifests without specific symptoms. The most common presentation is upper gastrointestinal bleeding, as occurred in our patient. Liver cirrhosis is one of the most frequent cause of PT. Up to 65% of these patients present an associated prothrombotic state, including protein S deficiency. Our case reminds us of the importance of a systematic search for hipercoagulability syndromes in patients with TP, even when the etiology can be conferred to liver cirrhosis.  相似文献   
1000.
A new, sensitive method combining seminested polymerase chain reaction (PCR) and heteroduplex analysis was used to detect follicular lymphoma (FL) cells in peripheral blood. Based on the detection of IgH rearrangement in DNA from peripheral blood leukocytes, the method demonstrated the presence of monoclonal B cells in FL patients with high frequency.  相似文献   
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