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81.
目的:研究肝郁痰凝型乳腺癌的钼靶X线影像特点,探讨其病理基础。方法:观察41例中医证型为肝郁痰凝型、术后病理检查结果为乳腺癌患者的钼靶X线影像表现,对其病理学基础进行分析。结果:41例肝郁痰凝型乳腺癌中,乳腺类型以致密型及混合型居多(占78%)。异常血管征及透环征出现频率较高(占80%以上)。腋淋巴结转移出现频率偏低(占12%)。结论:(1)肝郁痰凝型乳腺癌患者,乳腺密度多偏高,可能与较多发生在绝经期前有关。(2)肿瘤周围透亮环征象及异常血管征象出现频率较高,表明此型患者肿块周围脂肪代谢异常较为普遍及血管生长刺激因子分泌较多。(3)腋窝淋巴结转移者所占比例较小,可能是由于此类患者多属于癌变早、中期,相对气血不足或脾肾虚弱等正虚表现不明显。  相似文献   
82.
New tumor-specific contrast agents for clinical imaging and therapy for cancer are required. To this end Gd-H (Gd-hematoporphyrin), Gd-TCP (Gd-tetra-carboranylmethoxyphenyl-porphyrin), Gd-DTPA-WM53, and Gd-DTPA-9.2.27 were synthesized and administered by systemic injection to nude mice with human melanoma (MM-138) xenografts. The biodistribution T1 relaxation times and magnetic resonance (MR) image signal enhancement of the contrast agents are presented for the first time and compared for each group of five mice. A change (20%) in T1 relaxation times of water in human melanoma tumor xenografts was revealed 24 hours after injection of the labeled immunoconjugate Gd-DTPA-9.2.27. The percent of injected antibody or gadolinium that localized to the tumor was measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) to be approximately 35%. A higher concentration of gadolinium was achieved compared with nonspecific compounds, indicating selective delivery of Gd-DTPA-9.2.27 to the melanoma xenografts. Porphyrin-based contrast agents (Gd-H and Gd-TCP) also showed significant uptake in melanomas. The uptake of Gd-TCP by the tumor was sufficient to deliver boron atoms into the tumor, making possible dual use for both MR imaging (MRI) and boron neutron capture therapy (BNCT). The linear relationship found between the paramagnetic contribution to the relaxation rates and contrast agent concentration allows quantitative studies of paramagnetic contrast agent uptake.  相似文献   
83.
目的评价中心静脉导管留置治疗胸腔积液的疗效。方法257例胸腔积液患者分为两组,治疗组207例,应用胸腔留置中心静脉导管治疗;对照组50例,常规胸穿抽液治疗,观察并比较不同治疗方法的疗效、并发症等指标。结果两组对比多项指标差异有显著性(P〈0.05)。结论采用中心静脉导管治疗胸腔积液可减少胸穿次数、降低反应,提高治愈率。  相似文献   
84.
85.
Objective : To determine antibody levels to the Australian manufactured combined diphtheria, tetanus and pertussis (DTP) vaccine (Triple Antigen, CSL Ltd) in infante before and after their primary immunization course.
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy.  相似文献   
86.
87.
Effective targeted cancer therapy requires high selectivity and cytotoxicity. To this end we have prepared and tested a new alpha-emitting radioimmunoconjugate (RIC) against malignant melanoma. The melanoma antibody 9.2.27 is specific for most melanoma cell lines. This antibody was labelled with an a emitter, bismuth-213 (213Bi), and a positron emitter, terbium-152 (152Tb), which is an analogue of the alpha-emitting radioisotope terbium-149. The chelators cDTPAa (a cyclic anhydride of diethylenetriamine pentacetic acid) and CHX-A" (a 2-(p-SCN-Bz)-cyclohexyl-DTPA ligand) were used in order to obtain high labelling yields for both isotopes with either chelator. The labelling efficiency with 213Bi was found to be 96% and 92% with cDTPAa and CHX-A", respectively. With 152Tb it was 93% and 89%, respectively. Serum stability studies showed 20% leaching with 213Bi over a period of 2.5 half-lives. For 152Tb the leaching was 13%. There was no difference in the melanoma cell binding of the labelled and unlabelled antibodies. DNA synthesis data were compared for both isotopes with either chelator. Based on these results, the therapeutic activity ratio for 213Bi a particles and 152Tb positrons for the same endpoint was calculated to be 120. The stability of the bismuth and terbium RICs, together with the outstanding cytotoxicity of the alpha emitter, provides the basis for a new approach to the potential control of micrometastatic melanoma.  相似文献   
88.
89.
BACKGROUND: Imatinib inhibits the c-kit tyrosine kinase, which, accounts for its activity in gastrointestinal stromal tumors. The presence of c-kit protein expression in small cell lung carcinoma (SCLC) tumor specimens, as well as in vitro data supporting the role of c-kit in autocrine and paracrine growth stimulation specifically in SCLC, provided a rationale for studying imatinib in this disease. The authors conducted a Phase II single-institution study of imatinib in patients with recurrent SCLC whose tumor specimens expressed c-kit protein. METHODS: Patients with progressive SCLC after one or two previous chemotherapy regimens consented to have their tumor specimens screened by immunoperoxidase stain (CD117, Dako Corporation, Carpinteria, CA) for c-kit protein expression. If present, individuals were then eligible for treatment with an imatinib dose of 400 mg orally twice daily (total, 800 mg per day). RESULTS: The presence of c-kit protein was assessable in 36 of 39 (92%) tumor samples. Twenty-eight (78%) tumor samples had immunohistochemical staining for c-kit protein. Twelve patients were enrolled in the treatment portion of the current study. No responses were observed, and all patients had disease progression by Week 4. Edema, fatigue, nausea, and electrolyte abnormalities were the primary toxicities. CONCLUSIONS: Imatinib did not have antitumor activity against SCLC, even with c-kit protein present in tumor specimens. The dismal prognosis for these patients with progressive SCLC emphasized the urgent need for continued studies of new therapies in this population.  相似文献   
90.
Considerable variation in end-of-life decision making is reported between intensive care units in the United Kingdom, possibly because of differences in casemix. Senior medical staff within any one unit should, however, be consistent in such decision making. We reviewed the medical records for a 4-year period to establish if there was consistency in our own unit. This revealed considerable variation in the apparent willingness of consultants to make end-of-life decisions, emphasising the subjective nature of these decisions. Personality typing (Myers-Briggs Type Indicator) of consultants revealed that those who had made more than the expected number of decisions had scores towards the judging end of the judging/perceiving domain.  相似文献   
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