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21.
Keiji Ogura Shigeki Fukuzawa Tomonori Habuchi Osamu Ogawa Osamu Yoshida 《International journal of urology》1997,4(6):561-565
Background :
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm3 for the 81 patients with p53-labeling index (LI) less than 10% and 337.2 ± 141.0 μn3 for the 30 patients with p53 LI greater than 10% (P = 0.008). There was Resign if icant correlation between NRF and expression of p53. The mean MNV was 220.1 ± 1 20.5 μm3 for the 67 patients with PCNA LI less than 28% (the mean value of PCNA LI) and 328.9 ± 149.2 μm3 in 44 patients with PCNA LI greater than 28% (P= 0.0001). The mean NRF was 80.7 ± 4.2 for the 67 patients with PCNA LI less than 28%, and 82.3 ± 3.4 for the 44 patients with PCNA LI more than 28% (P= 0.04). Conclusion: Nuclear morphometric findings may reflect the proliferative potential of cancer eel Is of the bladder, as indicated by findings of immunostaining for p53 and PCNA. 相似文献
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm
22.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
23.
Danuta Wasserman Christer HellstrÖm Jerzy Wasserman Olof Beck Eva Andersson Marie Åsberg 《Archives of Suicide Research》1997,3(3):153-169
The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function. 相似文献
24.
Chihaya Maesawa Gen Tamura Yasushi Suzuki Kaoru Ishida Kazuyoshi Saito Ryoichi Satodate 《Cancer science》1992,83(12):1253-1256
For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR-SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR-SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR-SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors. 相似文献
25.
VEGF和p53在胰腺癌中的表达及意义 总被引:1,自引:0,他引:1
目的 探讨胰腺癌组织中血管内皮生长因子 (VEGF)及p5 3蛋白的表达及其临床病理意义。方法 采用SP免疫组织化学方法 ,对 46例胰腺癌组织中VEGF及 p5 3蛋白的表达进行检测。结果 VEGF与 p5 3表达率分别为 65 .2 %和 5 8.7%。p5 3表达与VEGF表达呈明显正相关(P <0 .0 5 )。VEGF表达与胰腺癌淋巴结转移 (P <0 .0 5 )和远处转移 (P <0 .0 1)显著相关 ,而与肿瘤大小 ,病理学分级无关 ,p5 3表达与胰腺癌远处转移 (P <0 .0 5 )显著相关 ,而与肿瘤大小 ,病理学分级及淋巴结转移无关。结论 在胰腺癌中 ,VEGF表达与 p5 3蛋白的表达呈正相关 ,在胰腺癌的转移中起重要作用 相似文献
26.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义 总被引:1,自引:1,他引:0
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。 相似文献
27.
28.
幕上星形细胞肿瘤MRI表现与VEGF、P16、Ki-67相关性研究 总被引:1,自引:0,他引:1
探讨星形细胞肿瘤MRI表现与P16、Ki—67、血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的相关性。材料和方法:收集我院术前经MRI诊断并经手术病理证实的幕上星形细胞肿瘤53例,行常规平扫描后静脉注射Gd—DTPA增强成像;同时采用HE染色及链菌素生物素—过氧化酶连接法进行VEGF、Ki—67、P16的免疫组织化学染色,测定它们的表达指数。结果:星形细胞肿瘤的信号不均匀性、坏死、水肿、占位效应、强化程度与VEGF、Ki—67、P16的表达相关,且随着星形细胞肿瘤恶性程度的增高VEGF、Ki—67的表达增加;P16的表达率降低。结论:星形细胞肿瘤的MRI表现与VEGF、Ki—67、P16的表达密切相关,MRI可以间接判断星形细胞肿瘤的某些生物学行为。 相似文献
29.
Martina Plísková Jan Vondrácek Borivoj Vojtesek Alois Kozubík Miroslav Machala 《Toxicological sciences》2005,83(2):246-256
Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BaP), are carcinogens suggested to be involved in development of human cancer. Several recent studies have reported that PAHs can activate estrogen receptors (ER), either directly or indirectly by producing estrogenic metabolites. We hypothesized that the activation of ER by PAHs or their metabolites could induce cell proliferation in estrogen-sensitive cells. In the present study, we found that two PAHs, benz[a]anthracene (BaA) and BaP, can stimulate proliferation of human breast carcinoma MCF-7 cells at concentrations 100 nM and higher. This effect was ER-dependent, because it was blocked by the pure antiestrogen ICI 182,780. Although both PAHs partially inhibited S-phase entry and DNA synthesis induced by 17beta-estradiol, they stimulated S-phase entry when applied to MCF-7 cells synchronized by serum deprivation. This was in contrast with model antiestrogenic aryl hydrocarbon receptor ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin, which fully suppressed S-phase entry. BaP, which is a strong mutagen, was found to induce p53 tumor suppressor expression, a partial S-phase arrest and at higher concentrations also cell death. Pifithrin-alpha, a synthetic inhibitor of p53 activity, abolished both S-phase arrest and apoptosis induced by genotoxic PAHs, and it potentiated the proliferative effect of BaP. Thus, both genotoxic and nongenotoxic events seem to interact in the effects of BaP on cell proliferation. Taken together, our data indicate that both BaA and BaP can stimulate cell proliferation through activation of ER. The proliferative effects of these carcinogenic compounds might contribute to tumor promotion in estrogen-sensitive tissues. 相似文献
30.
82例高血压患者16项人格特质测验 总被引:1,自引:0,他引:1
研究目的应用卡特尔16项人格特质测验探讨原发性高血压患者的人格特征。研究背景高血压病是危害人类健康的常见病之一,发病率逐年上升,但其病因至今尚未阐明,故有必要从心理、人格方面来探讨高血压的发病原因,以利于高血压病的防治。研究方法本文对82例均由2名以上内科医师确诊为原发性高血压、且现在高压仍保持在20/12.7kPa以上的患者进行卡特尔16项人格特质测验,并与78例人群对照分析。结果高血压患者在C-稳定性、E-峙强性、Q-紧张性以及在双重人格因素类型中的适应与焦虑方面与正常对照组有显著差异(P<0.05)。结论心理-社会因素是促使高血压发生的重要因素,它对高血压病因的阐明有重要意义,同时也使我们越来越重视运用心理、行为疗法,如生物反馈、各种松驰疗法等去防治高血压。 相似文献