全文获取类型
收费全文 | 11291篇 |
免费 | 593篇 |
国内免费 | 112篇 |
专业分类
耳鼻咽喉 | 111篇 |
儿科学 | 203篇 |
妇产科学 | 149篇 |
基础医学 | 1305篇 |
口腔科学 | 237篇 |
临床医学 | 785篇 |
内科学 | 3225篇 |
皮肤病学 | 202篇 |
神经病学 | 725篇 |
特种医学 | 339篇 |
外科学 | 2134篇 |
综合类 | 62篇 |
预防医学 | 329篇 |
眼科学 | 143篇 |
药学 | 711篇 |
中国医学 | 33篇 |
肿瘤学 | 1303篇 |
出版年
2024年 | 9篇 |
2023年 | 117篇 |
2022年 | 228篇 |
2021年 | 366篇 |
2020年 | 215篇 |
2019年 | 282篇 |
2018年 | 377篇 |
2017年 | 220篇 |
2016年 | 349篇 |
2015年 | 358篇 |
2014年 | 441篇 |
2013年 | 489篇 |
2012年 | 872篇 |
2011年 | 907篇 |
2010年 | 482篇 |
2009年 | 392篇 |
2008年 | 730篇 |
2007年 | 781篇 |
2006年 | 710篇 |
2005年 | 722篇 |
2004年 | 650篇 |
2003年 | 536篇 |
2002年 | 606篇 |
2001年 | 99篇 |
2000年 | 75篇 |
1999年 | 87篇 |
1998年 | 110篇 |
1997年 | 105篇 |
1996年 | 75篇 |
1995年 | 70篇 |
1994年 | 75篇 |
1993年 | 58篇 |
1992年 | 36篇 |
1991年 | 38篇 |
1990年 | 25篇 |
1989年 | 29篇 |
1988年 | 37篇 |
1987年 | 28篇 |
1986年 | 25篇 |
1985年 | 23篇 |
1984年 | 29篇 |
1983年 | 25篇 |
1982年 | 9篇 |
1981年 | 22篇 |
1980年 | 15篇 |
1979年 | 10篇 |
1978年 | 9篇 |
1977年 | 14篇 |
1975年 | 7篇 |
1974年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
It has been reported that a number of toxic agents impair normal vitamin A (VA) metabolism (A. D. Bruin, 1976, In Biochemical Toxicology of Environmental Agents, pp. 937–980. Elsevier, Amsterdam). A study was conducted to explore the effect of cadmium chloride (CdCl2) on VA metabolism. Female rats of the Wistar strain were given drinking water containing 50 ppm of cadmium (Cd) for 237 days. Cadmium ingestion did not affect the food intake and body weight, but a significant decrease in serum VA was observed, concurrently with an increase in liver VA. In studying ingestion of tritiated VA alcohol (all trans-[15-3H]retinol), it was found that the absorption of VA alcohol from the intestine, the release of newly absorbed VA from the liver to serum, and the conversion of VA to water-soluble metabolites in the liver were not influenced by Cd. These findings suggest that Cd interfered with the release of VA, especially stored VA, to serum. 相似文献
52.
53.
54.
Carbonic anhydrase II is a tumor vessel endothelium-associated antigen targeted by dendritic cell therapy. 总被引:3,自引:0,他引:3
Kenta Yoshiura Takashi Nakaoka Toshihide Nishishita Katsuaki Sato Akifumi Yamamoto Shinji Shimada Toshiaki Saida Yutaka Kawakami Tsuneo A Takahashi Hiroyuki Fukuda Shinobu Imajoh-Ohmi Naoki Oyaizu Naohide Yamashita 《Clinical cancer research》2005,11(22):8201-8207
Tumor-associated antigens are promising candidates as target molecules for immunotherapy and a wide variety of tumor-associated antigens have been discovered through the presence of serum antibodies in cancer patients. We previously conducted dendritic cell therapy on 10 malignant melanoma patients and shrinkage or disappearance of metastatic tumors with massive necrosis occurred in two patients. In this study, we found a 29-kDa protein against which antibody was elicited by dendritic cell therapy in one of the two patients. Matrix-assisted laser desorption ionization-time of flight/mass spectrometry analysis of the protein isolated by two-dimensional electrophoresis combined with Western blots revealed that the 29-kDa protein was carbonic anhydrase II (CA-II). Immunohistochemistry of the tumors and normal tissues showed that CA-II was expressed in the tumor vessel but not in normal vessel endothelium. CA-II expression in tumor endothelium was observed as well in other cancers including esophageal, renal, and lung cancers. In an in vitro angiogenesis model, CA-II expression of normal human vein endothelial cells was significantly up-regulated when cells were cultured in the acidic and hypoxic conditions indicative of a tumor environment. These findings suggest that CA-II is a tumor vessel endothelium-associated antigen in melanoma and other cancers, and elicitation of serum anti-CA-II antibody by dendritic cell therapy may be associated with good clinical outcome including tumor reduction. 相似文献
55.
Long-lasting renal dysfunction following tacrolimus induction therapy in ulcerative colitis patients
Na Cha Naoki Oshima Kenichi Kishimoto Satoshi Kotani Eiko Okimoto Tomotaka Yazaki Hiroki Sonoyama Akihiko Oka Yoshiyuki Mishima Kotaro Shibagaki Hiroshi Tobita Kousaku Kawashima Norihisa Ishimura Shunji Ishihara 《Journal of Clinical Biochemistry and Nutrition》2022,70(3):297
Although tacrolimus (TAC) has remarkable effects in ulcerative colitis (UC) patients when given as remission induction therapy, some can develop renal dysfunction during TAC administration, resulting in withdrawal, though related details remain poorly understood. This study was conducted to determine the impact of oral TAC on renal function for remission induction therapy in UC patients. Fifty-five patients (10 elderly, 45 non-elderly) with UC and treated with oral TAC at our hospital were retrospectively evaluated. Renal function was assessed using estimated glomerular filtration rate (eGFR). Although a high clinical response to TAC was seen in both elderly and non-elderly, a decline in eGFR was noted in nearly all patients regardless of age, with a maximum change of −34.4% from the baseline value at week 11. Furthermore, eGFR decline recovered quickly after TAC discontinuation, though did not return to the baseline at two years following cessation. The rate of eGFR change at week 12 was significantly associated with patient age (β = −0.3242, p = 0.0103) and peak serum trough level during TAC treatment (β = 0.3563, p = 0.0051). Furthermore, the rate of decline in eGFR was significantly greater during treatment with TAC in the elderly as compared to non-elderly, with a large difference in eGFR decline rate between those groups also noted at two years after withdrawal of treatment. Careful attention to renal function when administering oral TAC for UC is important and changes in eGFR should be monitored closely in elderly patients even after treatment cessation. 相似文献
56.
Daisuke Suzuki Yoshihiro Suzuki Daisuke Sato Kenji Kikuchi Naoki Kanauchi Akiko Nishida Yasuyuki Ohta 《Internal medicine (Tokyo, Japan)》2022,61(9):1443
Anti-voltage-gated potassium channel complex antibodies-mediated disorder includes Isaacs'' syndrome, which is characterized by neuromyotonia, and Morvan syndrome, which is characterized by neuromyotonia, encephalopathy and autonomic dysfunction. We herein report a patient with Morvan syndrome that converted from Isaacs'' syndrome after thymectomy. The patient first presented with myospasm in all extremities and positivity for both anti-leucine-rich glioma inactivated 1 (LGI1) and anti-contactin-associated protein like 2 (CASPR2) antibodies and subsequently developed encephalopathy after thymectomy, which was successfully improved by immunotherapy. This is the first case of Morvan syndrome wherein thymectomy worsened Isaacs'' syndrome, suggesting that immunotherapy should be considered for Isaacs'' syndrome accompanied by positivity for both anti-LGI1 and anti-CASPR2 antibodies to prevent worsening to Morvan syndrome. 相似文献
57.
A novel dimeric flavonol glycoside linked through a methylene group, kunzeagin A (1), and six new chromone C-glucosides, kunzeachromones A-F (2-7), were isolated along with seven known compounds from the leaf extract of Kunzea ambigua. The structures of these compounds were elucidated on the basis of spectroscopic analyses and chemical properties. Kunzeachromones A-F provided additional examples of galloylated C-glucosidic chromones occurring in the Myrtaceae. Kunzeagin A (1) and major constituents of this plant (6-C- and 8-C-glucosylchromones and their monogallates) exhibited potent inhibitory effects on activation of Epstein-Barr virus early antigen induced by 12-O-tetradecanoylphorbol 13-acetate in Raji cells. 相似文献
58.
ObjectivesNo studies have examined the association between preterm birth rates and socioeconomic factors in Japan using nationwide statistical data. We analyzed the association between preterm birth rates and household occupation using Vital Statistics data.MethodsAggregated Vital Statistics data from Japan from 2007 to 2019 were obtained from the Ministry of Health, Labour and Welfare. From the data, the number of births according to year, age group, gestational period, number of pregnancies, and household occupation were used in this study. Crude preterm birth rates and preterm birth rates adjusted by maternal age according to household occupation were calculated for each year. Poisson regression analysis was conducted to evaluate the association between household occupation and preterm births.ResultsUnemployed households had the highest preterm birth rate, and households with an occupation classification of “full-time worker 2” (an employee at a large company, civil servant, or board member) had the lowest preterm birth rate throughout each period. Poisson regression analysis revealed that unemployed households were statistically significantly associated with a high preterm birth risk. In contrast, the preterm birth rate adjusted by maternal age remained stable throughout each period regardless of household occupation, and preterm birth rates were found not to have increased in recent years in Japan.ConclusionsUnemployed households had higher preterm birth rates than other household occupations. Further studies investigating the characteristics of unemployed households are needed to identify the reasons for this disparity. 相似文献
59.
Ultrasound-guided local injection of methotrexate to treat an invasive hydatidiform mole 总被引:2,自引:0,他引:2
Tsukihara S Harada T Terakawa N 《The journal of obstetrics and gynaecology research》2004,30(3):202-204
A 28-year-old Japanese woman had an invasive hydatidiform mole which was diagnosed by means of transvaginal ultrasonography. After the two initial courses of systemic methotrexate (MTX) therapy given over a period of weeks, the tumor was 14 mm in diameter and the surrounding blood supply remained rich. In addition to the two initial courses of systemic MTX therapy, local ultrasound-guided injection of MTX therapy was given three times, once per week. After the local MTX treatment, the betahCG level, which had been as high as 240 ng/mL, dropped to less than 0.1 ng/mL. We then gave two additional courses of systemic MTX therapy (once per week). More than 3 years have passed since the final systemic MTX therapy, and the patient's serum betahCG levels continue to be less than 0.1 ng/mL. An invasive mole can be treated with an ultrasound-guided local injection of MTX in addition to the established systemic MTX treatment. 相似文献
60.
Involvement of catalase in the endometrium of patients with endometriosis and adenomyosis 总被引:3,自引:0,他引:3
OBJECTIVE: To determine the distribution of catalase in eutopic and ectopic endometria in patients with endometriosis or adenomyosis. DESIGN: Retrospective randomized study. SETTING: Department of obstetrics and gynecology in a university hospital. PATIENT(S): Thirty-three patients with endometriosis, 36 with adenomyosis, and 47 fertile controls (total, 116 women). MAIN OUTCOME MEASURE(S): Semiquantitative immunostaining of endometrial cells obtained by biopsy sampling, followed by calculation of an evaluation nomogram score. RESULT(S): The score of catalase in the glandular epithelium of controls group fluctuated during the menstrual cycle; it was lowest in the early proliferative phase and peaked in the late secretory phase. In patients with endometriosis, catalase scores did not fluctuate during the cycle, and scores were high compared with controls throughout the menstrual cycle. Catalase scores did not vary in patients with adenomyosis, and scores in this group were consistently higher than those in patients with endometriosis throughout the cycle. CONCLUSION(S): Abnormal expression of catalase in the eutopic and ectopic endometrium strongly suggests pathologic involvement of free radicals in endometriosis and adenomyosis. 相似文献