全文获取类型
收费全文 | 8037篇 |
免费 | 444篇 |
国内免费 | 99篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 179篇 |
妇产科学 | 646篇 |
基础医学 | 906篇 |
口腔科学 | 124篇 |
临床医学 | 924篇 |
内科学 | 1650篇 |
皮肤病学 | 85篇 |
神经病学 | 524篇 |
特种医学 | 254篇 |
外科学 | 1073篇 |
综合类 | 183篇 |
预防医学 | 404篇 |
眼科学 | 76篇 |
药学 | 613篇 |
中国医学 | 115篇 |
肿瘤学 | 771篇 |
出版年
2023年 | 38篇 |
2022年 | 96篇 |
2021年 | 179篇 |
2020年 | 93篇 |
2019年 | 146篇 |
2018年 | 249篇 |
2017年 | 166篇 |
2016年 | 158篇 |
2015年 | 212篇 |
2014年 | 248篇 |
2013年 | 387篇 |
2012年 | 570篇 |
2011年 | 580篇 |
2010年 | 377篇 |
2009年 | 315篇 |
2008年 | 495篇 |
2007年 | 552篇 |
2006年 | 540篇 |
2005年 | 438篇 |
2004年 | 382篇 |
2003年 | 319篇 |
2002年 | 315篇 |
2001年 | 266篇 |
2000年 | 275篇 |
1999年 | 206篇 |
1998年 | 59篇 |
1997年 | 73篇 |
1996年 | 61篇 |
1995年 | 35篇 |
1994年 | 49篇 |
1993年 | 29篇 |
1992年 | 135篇 |
1991年 | 96篇 |
1990年 | 69篇 |
1989年 | 45篇 |
1988年 | 46篇 |
1987年 | 46篇 |
1986年 | 44篇 |
1985年 | 27篇 |
1984年 | 35篇 |
1983年 | 11篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 6篇 |
1979年 | 15篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1973年 | 7篇 |
1972年 | 7篇 |
1971年 | 10篇 |
排序方式: 共有8580条查询结果,搜索用时 31 毫秒
31.
Determination of flunarizine in rat brain by liquid chromatography-electrospray mass spectrometry 总被引:3,自引:0,他引:3
Fuh MR Hsieh CJ 《Journal of chromatography. B, Biomedical sciences and applications》1999,736(1-2):167-173
A rapid liquid chromatography-electrospray mass spectrometry (LC-ES-MS) assay for the determination of flunarizine (FZ) in rat brain has been developed. A C18 column and an isocratic elution were employed for the separation. Using post-column split, 64% of the eluent was introduced into the ES-MS system for detection. The [M+H]+ (m/z 406) and a fragmented ion (m/z 203) were detected using selected ion monitoring. The linear range of this assay was good, ranging from 0.05 to 5 microM (r2=0.99). The intra- and inter-day precisions showed relative standard deviations ranging from 1.4% to 2.0% and 1.3% to 2.9%, respectively. The application of this newly developed method was demonstrated by examining the pharmacokinetics of FZ in rat brain. 相似文献
32.
33.
34.
Hsieh BT Hsieh JF Tsai SC Lin WY Huang HT Ting G Wang SJ 《Nuclear medicine and biology》1999,26(8):741-972
Balloon angioplasty is a standard treatment for artherosclerotic coronary artery disease. However, its clinical value is reduced by a high restenosis rate. A new concept in preventing restenosis is the use of a liquid-filled balloon containing a beta-emitting radioisotope. In this study, we performed biodistribution studies of Re-188 perrhenate and Re-188 diethylenetriaminopentaacetate (DTPA) to assess the resulting organ dose values in the event of balloon rupture if these agents are used for the clinical inhibition of restenosis after percutaneous transluminal coronary angioplasty (PTCA). After injecting Re-188 preparations intravenously, rats were killed at 10 min, 30 min, 60 min, 2 h, and 6 h ( n =5 per group). Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (%ID/g or %ID/mL). In addition, urine excretion and thyroid gland uptake were evaluated in rats ( n=5 per group) with a gamma camera after administration of 37 MBq (1 mCi) of each agent. Our data showed that both agents were excreted primarily via urine. However, the excretion of Re-188 DTPA was much faster than that of Re-188 perrhenate via the urinary system. The biodistribution data revealed that radioactivity levels in the stomach and the thyroid gland were high in the perrhenate group but low in the Re-188 DTPA group. The concentration levels in other tissues including lung, liver, testis, muscle, and blood were low throughout this study for both agents. The thyroid radiation value in the Re-188 perrhenate group was 0.163 mGy/MBq, which was much higher than that of the Re-188 DTPA group (0.0167 mGy/MBq). The stomach radiation value was as high as 0.127 mGy/MBq for Re-188 perrhenate, compared with 0.013 mGy/MBq for Re-188 DTPA. In conclusion, in the event of balloon rupture, the release of Re-188 DTPA results in lower radiation doses than Re-188 perrhenate, especially to the thyroid gland and the stomach. Our data suggest that Re-188 DTPA is a useful radiopharmaceutical for endovascular irradiation. 相似文献
35.
Chen YC Hung CC Lin SF Chang SC Hsieh WC 《International journal of antimicrobial agents》1996,7(1):69-74
The safety and efficacy of flomoxef and latamoxef were compared in the treatment of hospitalized patients with sepsis and/or Gram-negative bacteremia in a prospective, open-labelled clinical trial. Patients were randomized to receive 1 to 2 g intravenous doses of either flomoxef every 6 to 12 h, or latamoxef every 8 to 12 h. Data from 21 patients given flomoxef and 23 patients given latamoxef were included in the evaluation of efficacy. Flomoxef produced clinical cure and satisfactory microbiological responses in 85.7% and 100% of patients, respectively. These results were similar to those obtained with latamoxef (87% and 100%, respectively). In addition, no significant difference was found in mean age, sex, severity of infection, distribution of pathogens and focus of infection between the two groups. However, the flomoxef group included more patients with ultimately fatal diseases. Six patients given flomoxef and two patients given latamoxef developed superinfections caused by yeast, enterococci and Pseudomonas aeruginosa in the urinary tract. Mild and reversible adverse reactions probably related to flomoxef and latamoxef were noted in 14.3% and 13% of patients, respectively. The results of this study demonstrated that flomoxef is a safe and effective antimicrobial agent in the treatment of patients with sepsis and/or Gram-negative bacteremia. 相似文献
36.
Doppler sonographic detection of reverse twin-twin transfusion after intrauterine death of the donor
We report a "stuck" twin, in which a reverse blood shunt from the recipient to the donor was detected by Doppler sonography after death of the donor. This acute reverse transfusion caused intrauterine fetal distress and severe neonatal anemia of the surviving recipient. We believe that acute hemodynamic change after death of one fetus, in addition to causing a derangement in coagulation, causes immediate danger or subsequent organ damage for the surviving co-twin. 相似文献
37.
38.
Doppler velocimetry of the umbilical and intraplacental fetal arteries was studied by color flow mapping in 39 normal pregnancies. The systolic-diastolic ratio (S/D) and pulsatility index of the intraplacental fetal artery downstream to the umbilical artery decreased significantly with advancing gestational age, and its S/Ds were persistently lower than those of the umbilical artery. The difference in the S/D between the umbilical artery and its intraplacental downstream branches decreased with advancing gestational age and approached zero as the pregnancy progressed to term. We conclude that intraplacental fetal arteries, possibly fetal arteries in main stem villi, can be imaged by color flow mapping and that there is a significant "resistance gradient" between the intraplacental fetal artery and the umbilical artery. Intraplacental fetal artery velocimetry using color flow mapping may give further insights into the umbilical-placental circulation. 相似文献
39.
Surgical Mortality, Survival, and Quality of Life after Resection for Gastric Cancer in the Elderly 总被引:13,自引:2,他引:11
Although there were some studies on clinicopathologic characteristics, operative morbidity, and mortality in elderly patients
with gastric cancer, no reports have specifically focused on survival and quality of life after resection. A total of 433
patients aged ≥ 65 years (1987–1994) who underwent gastric resection for gastric adenocarcinoma were studied. Two groups were
considered: patients aged 65 to 74 years and those > 74 years. Most of the patients (78.1%) had advanced diseases, and nearly
half (41.3%) had associated chronic disease(s). Resections with curative intention were performed in 362 patients (83.6%).
The overall operative morbidity rate was 21.7% and mortality rate 5.1%. Although operative procedures were similar in both
groups, patients aged >74 years had a higher mortality rate than those aged 65 to 74 years (10.1% vs. 3.5%; p= 0.034). Age and extent of gastric resection were two independent factors negatively affecting mortality. The cumulative
survival rates for patients who underwent curative resection were 86.2%, 72.4%, 67.2%, 62.9%, and 60.0% at 1, 2, 3, 4, and
5 years, respectively. Nearly all patients (96%) after surgery had normal work and daily activities. Some patients appeared
to lack energy (16%) or experienced a period of anxiety or depression. There was no statistical difference in survival and
quality of life assessed by the Spitzer index after curative resection between the two groups. Therefore resection with curative
intention can be performed for the elderly with acceptable morbidity and mortality rates, possible long-term survival, and
good quality of life, but a limited operation should be considered in the very elderly patients. 相似文献
40.
Characteristics of optic disc changes in Taiwanese patients with primary angle-closure glaucoma. 总被引:1,自引:0,他引:1
Chang-Hao Yang Por-Tying Hung Luke L-K Lin Jui-Wen Hsieh Tsing-Hong Wang I Jong Wang 《台湾医志》2003,102(3):183-188
BACKGROUND AND PURPOSE: Primary angle-closure glaucoma (PACG) is the predominant form of glaucoma among Asians. Although numerous studies have been done to describe the characteristic optic disc changes in patients with primary open angle glaucoma (POAG) which is the predominant form of glaucoma among Western populations, few studies have evaluated the optic disc changes in patients with PACG. The aim of this study was to elucidate the characteristic intrapapillary and parapapillary disc changes in PACG in a cross-sectional study and to develop a practical approach to the detection of glaucomatous optic disc changes in PACG by ophthalmoscopic examination. METHODS: A total of 103 eyes in 103 PACG patients were studied. Forty one eyes of 41 age- and sex-matched healthy subjects served as controls. Three glaucoma-trained subspecialists examined stereophotographs of optic discs to evaluate the intrapapillary and parapapillary changes. The differences in PACG and control group eyes were compared. RESULTS: Concentric steep enlargement of the optic disc was found in 99 PACG eyes (96%). Local notching was noted in only 3 eyes, and vertically oval-shaped cupping of the optic disc in only 1 eye. Disc hemorrhage was not detected in any eye. Parapapillary atrophy of the alpha zone involving both temporal and nasal side of the optic disc and parapapillary atrophy of beta zone were significantly more frequent in the PACG group. The presence of an alpha zone or a beta zone simultaneously involving both the temporal and nasal side of the optic disc was associated with more severe optic nerve head damage. CONCLUSIONS: The intrapapillary change in the PACG group eyes reflected the development of cupping in PACG patients with small and compact optic discs. The parapapillary atrophy paralleled the intrapapillary optic disc cupping in eyes of the PACG group. 相似文献