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921.
掌背动脉蒂逆行掌骨瓣移位治疗指骨骨折不连接   总被引:2,自引:0,他引:2  
为设计以掌背动脉为蒂的逆行掌骨瓣移位,对12侧新鲜成人上肢标本进行解剖观察,发现手的掌背动脉在指蹼处与指革侧总动脉有恒定的吻合支.并发出1~3条小分支至2~5掌骨基底部.临床应用掌背动脉蒂逆行掌骨瓣移位治疗指骨骨折不连接6例,掌骨瓣最大1.2cm×0.5cm×0.5cm,最小0.7cm×0.5cm×0.5cm。指骨均在2.5~3个月内骨性愈合,经术后8~10个月随访,按TAM标准评价,关节功能恢复优良率达80%.本术式提供有血运的活骨,加速骨折愈合,为治疗指骨骨折不连接提供了一个好的手术方法.  相似文献   
922.
组织工程颅骨缺损修复过程中超微结构观察   总被引:2,自引:0,他引:2  
目的 用组织工程骨修复SD大鼠颅骨极量骨缺损,并在透射电镜下观察骨修复过程中成骨细胞、血管内皮细胞与陶瓷支架的关系。方法 14只雄性SD大鼠,随机分成实验组和对照组,每组7只。取左侧腔、股骨骨髓,体外诱导培养骨髓基质细胞。实验组将已分化的成骨细胞与含孔磷酸钙陶瓷复合用于修复大鼠自体颅骨极量骨缺损;对照组颅骨缺损处仅置入无细胞的陶瓷材料。分别于术后4、8、12、16、20、24及28周每组各处死1只动物取材,制成脱钙超薄切片,透射电镜下观察成骨细胞、血管内皮细胞与陶瓷残余支架的关系。结果 实验组动物颅骨修复12周前成骨细胞或成骨细胞样细胞毗邻新生小血管、血管内皮细胞存在,16周后成骨细胞转变为骨细胞,并围绕血管被包埋于骨基质及胶原纤维中;陶瓷残余与新生骨间有一条明显的钙化沉积带,大量胶原纤维已伸入到陶瓷支架的纳米级结构中。对照组陶瓷中央部位有大量小血管及血管内皮细胞增生,其周围多为幼稚成纤维细胞,无成骨细胞与血管内皮细胞的依附关系。结论 新型含孔磷酸钙陶瓷作为组织工程细胞支架,其间的纳米级结构有利于骨的再生和血管形成;未见来源于植骨床血管的内皮细胞衍变为成骨细胞。  相似文献   
923.
Sixty women with breast cancer (mean age: 61 years; range 36-78 years) were treated with Epirubicin (4’epi-Dox-orubicin), 60 mg m-2 , as single drug therapy. The drug was administered as 2 hours’ constant rate infusions. The pharmacokinetics of the drug during the first course of treatment was evaluated by measurements of the plasma concentration of Epirubicin at the end of the infusion period. There was a five-fold inter-individual variation of the dose-normalized maximum plasma concentration, which increased with increasing age of the patients. There was no correlation between this pharmacokinetic parameter and degree of obesity.  相似文献   
924.
Bone disorders following gastrectomy were studied by measuring absolute and relative bone mineral density of the Wards triangle, serum 1,25-(OH)2-D, alkaline phosphatase, and total serum calcium. The subjects were 20 males who had undergone total gastrectomy not more than three months previously (group A1). Seventeen of these patients were reviewed three years later (group A2). Absolute and relative bone density were significantly lower in group A2 than in A1 (0.52 ± 0.011 g/cm2 versus 0.6 ± 0.014 g/cm2,P<0.01 and 85.5 ± 1.4% age-matched control versus 95 ± 1.3%,P<0.01). 1,25-(OH)2-D was significantly lower in group A2 than in group A1 (14.3 ± 0.97 pg/ml versus 20.6 ± 1.02 pg/ml,P<0.01). There was no difference in alkaline phosphatase and calcium serum concentration. The mean weight loss was 6.26 ± 0.57% over the follow-up period, and weight loss correlated with absolute and relative bone density (r=–0.74,P<0.01). There was a positive correlation between 1,25-(OH)2-D and absolute or relative bone density (r=0.67,r=0.62 andP<0.01). These data suggest that bone density decrease has already occurred three years after total gastrectomy and is positively correlated to 1,25-(OH)2-D deficiency. As no differences in serum alkaline phosphatase and serum calcium concentration were found, these factors are of little value for the early detection of postgastrectomy bone disorders, whereas weight loss is a valuable screening parameter.  相似文献   
925.
不同病因所诱发的肺癌细胞类型不同已被一些研究所肯定。本文对978例肺癌细胞类型的分析表明:男性以鳞癌为主,女性则腺癌较多。将1980—83年与1984—87年的病例进行比较,发现男性有鳞癌下降和腺癌上升的趋势,女性则相反。鳞癌和小细胞癌均中央型多于周围型,但腺癌未见这种差别。各种细胞类型的肺癌均右肺多见于左肺。吸烟可使鳞癌的发生率上升,在男性尤为明显。接触煤烟尘、炊事活动以及居住点大气污染因素对肺癌细胞类型的构成,尚未发现有明显的影响。  相似文献   
926.
10 patients with chronic adult periodontitis who had greater than 1 tooth with infra-bony pockets were treated at the test defects by periodontal flap procedures with implantation of hydroxylapatite particles; the control defects were treated by the same surgical procedures but without the implant. A total of 58 test defects and 59 control defects were treated. Each defect had measurements carried out at given sites on the involved tooth surfaces, the sites being considered for subsequent tabulation purposes under the category of shallow (less than 3 mm) moderate (3-6 mm) and deep (greater than 6 mm) initial pocket depths. There were 146 and 152 shallow sites, 216 and 241 moderate sites and 140 and 133 deep sites, at test and control sites, respectively. Measurements of recession, probing pocket depths and probing attachment levels were made at 6 months and 1, 2, 3 and 4 years. At all sites over the period of the study, for the moderate and deep initial pockets there was a significant reduction in probing depths and an increase in the probing attachment levels. At the 4th year of assessment for the initially deep pockets, the reduction in probing depths was significantly greater for the sites treated with the implant material. In view of the difficult clinical problem posed by the treatment of teeth with deeper periodontal bone defects, further research using either this type of implant material or similar material should be considered.  相似文献   
927.
Thirty patients with metastatic breast carcinoma to the liver underwent systemic chemotherapy. Twentyfour of these patients also received hepatic arterial infusion chemotherapy, three in conjunction with hepatic artery embolization. The morphologic changes of the liver believed to be due to chemotoxic effect of treatment occurred in 27 patients, and were evaluated by serial computed tomography (CT) examinations. These included fatty changes in seven patients, severe cirrhotic changes in four, localized atrophy with regional contour changes in three, and areas of low density in the regions of previously treated metastases in 13. The CT features of cirrhosis included density changes along with nodular irregularity of the hepatic borders with marked decrease in liver size and development of ascites.  相似文献   
928.
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.  相似文献   
929.
Summary Female BDF1 mice inoculated with MXT (3.2) estrogen independent mouse mammary carcinoma were treated for three weeks with microcapsules of the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp6]LH-RH, the antagonist SB-75, the somatostatin analog RC-160, or combinations. The lack of estrogen dependence of the tumor was proved by bilateral surgical ovariectomy, which had no effect. In two experiments, treatment with 25µg/day doses of each analog alone resulted in a significant inhibition of tumor growth as shown by a 40–53% inhibition of tumor volumes, 38–43% decrease in tumor weights, and histological signs of tumor regression. However, the combination of SB-75 or [D-Trp6]LH-RH with somatostatin analog RC-160 caused greater reduction of tumor volume (68 and 61%) or tumor weights (59 and 56%), than single analogs, and histologically the occurrence of apoptosis and decrease in AgNOR numbers was more pronounced in the groups receiving combination therapy. Specific binding sites for [D-Trp6]LH-RH, EGF, and IGF-I were demonstrated in the tumor membranes. The binding capacity of LH-RH receptors was decreased by treatment with the analogs, the greatest down-regulation being caused by combination therapy. A significant decrease in EGF binding capacity was observed after treatment with the LH-RH analogs, alone or especially in combination with somatostatin analog RC-160. The combination of these analogs also caused a reduction in IGF-I receptors. The finding that LH-RH agonists and antagonists and somatostatin analogs inhibit the growth of estrogen independent mammary tumors, and that combinations are more effective than single analogs, might be of practical importance in human breast cancer therapy.  相似文献   
930.
A stable cell line, KHM-3S, was established from a patient with small cell lung cancer (SCLC), who had a high serum level of soluble interleukin 2 receptors (sIL2-R) and was seropositive for human T cell leukemia virus (HTLV)-l. KHM-3S cells were positive for IL2-R (Tac) and NKH-1, but negative for other lymphocytic markers such as OKT 11, OKT 4, OKT 8, T cell receptor (WT 31), B 1, and B 4. Moreover, the KHM-3S cells were negative for leukocyte common antigen and strongly positive for neuron-specific enolase (NSE). Secretion of sIL2-R and NSE by the KHM-3S line was detected by an enzyme-linked immunosorbent assay. Rearrangement of the T cell receptor gene and monoclonal HTLV-1 integration were found by Southern blot analysis of KHM-3S DNA. However, Northern blot analysis showed no T cell receptor mRNA. KHM-3S may be useful for studies on the role of HTLV-1 in carcinogenesis and IL2-R expression in SCLC.  相似文献   
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