全文获取类型
收费全文 | 481篇 |
免费 | 14篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 3篇 |
妇产科学 | 15篇 |
基础医学 | 33篇 |
口腔科学 | 32篇 |
临床医学 | 63篇 |
内科学 | 83篇 |
皮肤病学 | 3篇 |
神经病学 | 23篇 |
特种医学 | 29篇 |
外科学 | 41篇 |
综合类 | 10篇 |
预防医学 | 41篇 |
眼科学 | 2篇 |
药学 | 55篇 |
中国医学 | 2篇 |
肿瘤学 | 75篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 18篇 |
2013年 | 26篇 |
2012年 | 34篇 |
2011年 | 29篇 |
2010年 | 14篇 |
2009年 | 13篇 |
2008年 | 25篇 |
2007年 | 40篇 |
2006年 | 24篇 |
2005年 | 24篇 |
2004年 | 17篇 |
2003年 | 31篇 |
2002年 | 32篇 |
2001年 | 29篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1983年 | 4篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1968年 | 1篇 |
1965年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有517条查询结果,搜索用时 15 毫秒
31.
Lee YL Shih CM Chiou HL Shiau MY Chang GC Chang YH 《Clinica chimica acta; international journal of clinical chemistry》2004,349(1-2):87-96
BACKGROUND: Correlation between p53 autoantibodies (p53 Abs) titers and the efficacy of Taiwanese lung cancer patients undergoing chemotherapy has never been investigated. Our present study aimed at evaluating putative possibility of using p53 Abs levels as a model system to monitor effect of chemotherapy and prognosis prediction of lung cancer. METHODS: The prevalence of p53 Abs in lung cancer patients and temporal alteration of p53 Abs titers in lung cancer patients carrying p53 Abs were investigated by using ELISA and Western blot analysis. RESULTS: p53 Abs was detected in 17 of 277 (6.14%) lung cancer patients, the positivity of p53 Abs in patients with small cell lung carcinoma and non-small cell lung carcinoma was 4.88% and 6.36%, respectively. No significant association between p53 Abs and patients' clinical manifestations was found. Titer of p53 Abs was decreased in 6 of 17 p53 Abs-carrying patients after chemotherapy. However, the decreasing p53 Abs titers were not correlated with patients' survival or chemotherapeutic efficacy. CONCLUSIONS: The prevalence of p53 Abs in Taiwanese lung cancer is much lower than that in Caucasians. It is unlikely that p53 Abs titer could be a monitoring indicator for the chemotherapeutic efficacy or a prognosis indicator of lung cancer. 相似文献
32.
Aims: To investigate time to pregnancy (TTP) in male lead workers in order to determine the dose-response relation between blood lead and decreased fecundity. Methods: A total of 163 currently employed married male lead battery workers were classified into five categories of exposure based on questionnaire information and annual individual blood lead measurement. Information pertaining to the TTP was collected using personal interviews with 133 men and their spouses, with 280 valid pregnancies. The fecundability ratios (FRs) were calculated with the Cox discrete proportional hazard regression technique to evaluate the effects of lead exposure. Results: After other factors associated with TTP were controlled for, there was a dose-response relation between blood lead level and TTP. The measured FRs were 0.90 (95% CI 0.61 to 1.34), 0.72 (0.46 to 1.11), 0.52 (0.35 to 0.77), and 0.40 (0.27 to 0.59) for concurrent blood lead levels of <20, 20–29, 30–39, and ⩾40 µg/dl, respectively. Paired self comparison was also performed for 41 couples that had pregnancies prior to lead exposure and pregnancies with male occupational lead exposure. The TTP was prolonged for 0.15 cycles by a 1 µg/dl increase in blood lead. Conclusions: These results corroborate the hypothesis that a raised blood lead level affects fecundity. A blood lead level of less than 40 µg/dl may still significantly prolong TTP. 相似文献
33.
McDonald LC Lauderdale TL Shiau YR Chen PC Lai JF Wang HY Ho M;TSAR Participating Hospitals 《International journal of antimicrobial agents》2004,23(4):362-370
In the Taiwan Surveillance of Antimicrobial Resistance programme, isolates were collected from 21 hospitals over a 3-month period in 2000 (TSAR II) and rates of resistance in Gram-positive pathogens were determined. Resistance rates were high including oxacillin resistance in Staphylococcus aureus (60%) and coagulase-negative staphylococci (80%), high-level gentamicin resistance (HLGR) in Enterococcus faecalis (60%) and penicillin non-susceptibility in Streptococcus pneumoniae (69%). Oxacillin resistance had increased from 1998 (TSAR I) and may be spreading into outpatient settings. In contrast, less than 2% enterococci were vancomycin-resistant. No linezolid resistance was found in either staphylococci or enterococci. 相似文献
34.
OBJECTIVE: The purpose of this study was to compare the usefulness of gallium-67 citrate (67Ga) and technetium-99m tetrofosmin (Tc-TF) scan to detect Hodgkin's disease (HD). METHODS: In this study, 24 patients with HD underwent 67Ga and Tc-TF scan before receiving any therapy. RESULTS: 67Ga scan could detect HD in all 24 (100%) patients. Tc-TF scan could detect HD in 22/24 (91.6%) patients, but it was false-negative in one case of infradiaphragmatic HD and in another case with chemotherapy resistance. There was no significant difference in detection sensitivity between 67Ga and Tc-TF scan. CONCLUSIONS: We conclude that Tc-TF scan can not replace conventional 67Ga scan to detect HD. 相似文献
35.
The effectiveness of technetium-99m tetrofosmin (Tc-TF) single photon emission computed tomography (SPECT) of the head and neck for detecting recurrence of nasopharyngeal carcinomas (NPC) was evaluated and compared with computed tomography (CT). Both Tc-TF SPECT and CT of the head and neck were performed in 36 NPC patients 4 months after radiotherapy. All 36 then underwent histopathological examinations of nasopharyngeal biopsies. Based on the histopathological results, the sensitivity, specificity, and accuracy of visually interpreted Tc-TF SPECT images, to differentiation of recurrent NPC from benign lesions, were 64%, 96%, and 86%, respectively. The sensitivity, specificity, and accuracy of CT for detecting recurrent NPC were 73%, 88%, and 83%, respectively. The Tc-TF SPECT has a better specificity but a lower sensitivity to differentiate benign lesions and recurrent/residual NPC when compared with CT. Combined Tc-TF SPECT and CT sensitivity and specificity were 100% and 88%, respectively. There are much better either test alone. However, further studies, including a larger NPC patient population, are warranted to determine the exact role and clinical usefulness of Tc-TF SPECT to differentiate benign lesions and recurrent/residual NPC. 相似文献
36.
37.
Two growth experiments were conducted to estimate the minimum dietary iron requirement for juvenile hybrid tilapia, Oreochromis niloticus x O. aureus. Purified diets containing 0, 10, 30, 50, 100, 150, 200 and 400 mg Fe/kg from ferric citrate (Experiment 1) and 0, 10, 30, 50, 100, 150 and 200 mg Fe/kg from ferrous sulfate (Experiment 2) were fed to tilapia (mean initial weight: 0.63 +/- 0.01 g, Experiment 1; 0.64 +/- 0.01 g, Experiment 2) for 8 wk. In Experiment 2, 150 mg Fe/kg from ferric citrate was also included for comparison. The rearing water contained 1.07 micro mol/L iron, and supplemental levels were confirmed by analysis. Each diet was fed to three replicate groups of fish. In Experiment 1, weight gain and feed efficiency (FE) were highest (P < 0.05) in fish fed the diet supplemented with 150 mg Fe/kg, followed by fish fed diets with 50, 100 and 200 mg Fe/kg and lowest in fish fed the unsupplemented control diet. Hepatic iron concentration was highest in fish fed diets supplemented with >150 mg Fe/kg, followed by fish fed the diet with 100 mg Fe/kg and lowest in fish fed diets with =10 mg Fe/kg. Hemoglobin (Hb) and hematocrit (Hct) were higher in fish fed diets with >/=100 mg Fe/kg and mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were higher in fish fed diets with >/=150 mg Fe/kg than in fish fed the diet without iron supplementation. In Experiment 2, weight gain was higher in fish fed the diet with 50 mg Fe/kg than in fish fed diets with 150, 200 and =30 mg Fe/kg. FE was higher in fish fed diets with 50 and 100 mg Fe/kg and the ferric citrate comparison diet than in fish fed diets with =10 mg Fe/kg. Hepatic iron concentration was higher in fish fed diets with >/=50 mg Fe/kg and the ferric citrate comparison diet than fish fed diets with =30 mg Fe/kg. Hb, Hct, MCV and MCH were higher in fish fed diets with >/=50 mg Fe/kg than in fish fed the unsupplemented control diet. Analyses by polynomial regression of weight gain and by broken-line regression of hepatic iron and blood Hb concentrations indicated that the dietary iron requirement for tilapia is approximately 150-160 mg Fe/kg and 85 mg Fe/kg with ferric citrate and ferrous sulfate as the iron source, respectively; it also appears that ferric citrate was approximately 50% as effective as ferrous sulfate in meeting the iron requirement. 相似文献
38.
Phytoestrogen consumption and breast cancer risk in a multiethnic population: the Bay Area Breast Cancer Study 总被引:13,自引:0,他引:13
Horn-Ross PL John EM Lee M Stewart SL Koo J Sakoda LC Shiau AC Goldstein J Davis P Perez-Stable EJ 《American journal of epidemiology》2001,154(5):434-441
Research on the relation between phytoestrogens and breast cancer risk has been limited in scope. Most epidemiologic studies have involved Asian women and have examined the effects of traditional soy foods (e.g., tofu), soy protein, or urinary excretion of phytoestrogens. The present study extends this research by examining the effects of a spectrum of phytoestrogenic compounds on breast cancer risk in non-Asian US women. African-American, Latina, and White women aged 35-79 years, who were diagnosed with breast cancer between 1995 and 1998, were compared with women selected from the general population via random digit dialing. Interviews were conducted with 1,326 cases and 1,657 controls. Usual intake of specific phytoestrogenic compounds was assessed via a food frequency questionnaire and a newly developed nutrient database. Phytoestrogen intake was not associated with breast cancer risk (odds ratio = 1.0, 95% confidence interval: 0.80, 1.3 for the highest vs. lowest quartile). Results were similar for pre- and postmenopausal women, for women in each ethnic group, and for all seven phytoestrogenic compounds studied. Phytoestrogens appear to have little effect on breast cancer risk at the levels commonly consumed by non-Asian US women: an average intake equivalent to less than one serving of tofu per week. 相似文献
39.
Vaccination with the glycoprotein D gene of pseudorabies virus delivered by nonpathogenic Escherichia coli elicits protective immune responses 总被引:2,自引:0,他引:2
Attenuated intracellular bacteria, such as Salmonella and Shigella, have been exploited to act as gene delivery vectors. In this study, we report that nonpathogenic, live Escherichia coli can be used for the delivery of DNA vaccines in vivo, leading to generation of immune responses against plasmid-encoded foreign antigens. The pseudorabies virus (PrV) DNA vaccine carrying the glycoprotein D (gD) gene delivered by E. coli was able to induce protective immune responses in mice against a lethal PrV challenge. Co-delivery of E. coli carrying plasmid DNA encoding prothymosin alpha enhanced cellular immune responses to the PrV DNA vaccine delivered by E. coli. Our results suggest that nonpathogenic E. coli may be used as a vector for DNA vaccines in veterinary uses. 相似文献
40.
Iodine and thyroid cancer risk among women in a multiethnic population: the Bay Area Thyroid Cancer Study. 总被引:3,自引:0,他引:3
P L Horn-Ross J S Morris M Lee D W West A S Whittemore I R McDougall K Nowels S L Stewart V L Spate A C Shiau M R Krone 《Cancer epidemiology, biomarkers & prevention》2001,10(9):979-985
Research on the relationship between iodine exposure and thyroid cancer risk is limited, and the findings are inconclusive. In most studies, fish/shellfish consumption has been used as a proxy measure of iodine exposure. The present study extends this research by quantifying dietary iodine exposure as well as incorporating a biomarker of long-term (1 year) exposure, i.e., from toenail clippings. This study is conducted in a multiethnic population with a wide variation in thyroid cancer incidence rates and substantial diversity in exposure. Women, ages 20-74, residing in the San Francisco Bay Area and diagnosed with thyroid cancer between 1995 and 1998 (1992-1998 for Asian women) were compared with women selected from the general population via random digit dialing. Interviews were conducted in six languages with 608 cases and 558 controls. The established risk factors for thyroid cancer were found to increase risk in this population: radiation to the head/neck [odds ratio (OR), 2.3; 95% confidence interval (CI), 0.97-5.5]; history of goiter/nodules (OR, 3.7; 95% CI, 2.5-5.6); and a family history of proliferative thyroid disease (OR, 2.5; 95% CI, 1.6-3.8). Contrary to our hypothesis, increased dietary iodine, most likely related to the use of multivitamin pills, was associated with a reduced risk of papillary thyroid cancer. This risk reduction was observed in "low-risk" women (i.e., women without any of the three established risk factors noted above; OR, 0.53; 95% CI, 0.33-0.85) but not in "high-risk" women, among whom a slight elevation in risk was seen (OR, 1.4; 95% CI, 0.56-3.4). However, no association with risk was observed in either group when the biomarker of exposure was evaluated. In addition, no ethnic differences in risk were observed. The authors conclude that iodine exposure appears to have, at most, a weak effect on the risk of papillary thyroid cancer. 相似文献