全文获取类型
收费全文 | 178021篇 |
免费 | 1179篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 1128篇 |
儿科学 | 6742篇 |
妇产科学 | 3074篇 |
基础医学 | 17024篇 |
口腔科学 | 1542篇 |
临床医学 | 12626篇 |
内科学 | 31358篇 |
皮肤病学 | 743篇 |
神经病学 | 16755篇 |
特种医学 | 8943篇 |
外科学 | 29007篇 |
综合类 | 2330篇 |
一般理论 | 1篇 |
预防医学 | 18303篇 |
眼科学 | 2792篇 |
药学 | 9626篇 |
中国医学 | 626篇 |
肿瘤学 | 16599篇 |
出版年
2023年 | 28篇 |
2022年 | 54篇 |
2021年 | 99篇 |
2020年 | 66篇 |
2019年 | 115篇 |
2018年 | 21997篇 |
2017年 | 17410篇 |
2016年 | 19570篇 |
2015年 | 984篇 |
2014年 | 890篇 |
2013年 | 915篇 |
2012年 | 7190篇 |
2011年 | 21219篇 |
2010年 | 18912篇 |
2009年 | 11618篇 |
2008年 | 19652篇 |
2007年 | 21868篇 |
2006年 | 718篇 |
2005年 | 2335篇 |
2004年 | 3549篇 |
2003年 | 4535篇 |
2002年 | 2618篇 |
2001年 | 291篇 |
2000年 | 415篇 |
1999年 | 191篇 |
1998年 | 235篇 |
1997年 | 234篇 |
1996年 | 115篇 |
1995年 | 129篇 |
1994年 | 111篇 |
1993年 | 74篇 |
1992年 | 48篇 |
1991年 | 97篇 |
1990年 | 129篇 |
1989年 | 81篇 |
1988年 | 57篇 |
1987年 | 44篇 |
1986年 | 24篇 |
1985年 | 31篇 |
1984年 | 23篇 |
1982年 | 27篇 |
1980年 | 40篇 |
1974年 | 21篇 |
1939年 | 20篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 28 毫秒
81.
82.
83.
Kimberly A. Varker Edward W. Martin Dori Klemanski Bryan Palmer Manisha H. Shah Mark Bloomston 《Journal of gastrointestinal surgery》2007,11(12):1680-1685
Background
Transarterial chemoemobolization (TACE) is commonly used to treat metastatic carcinoid tumors; however, the management of
progressive disease is less clear. We sought to determine if patients with disease progression after TACE would benefit from
repeat TACE.
Methods
The records of 27 patients undergoing repeat TACE for radiologic or symptomatic progression after TACE for metastatic carcinoid
were reviewed and compared to 122 undergoing first TACE. Overall and progression-free survivals were estimated by the Kaplan–Meier
method.
Results
Mean disease-free interval after first TACE was 11.8 months. Radiologic response was observed in 61% compared to 82% after
first TACE (p = 0.058); hormone response in 64% compared to 80% (p = 0.159); and symptomatic response in 77% compared to 92% (p = 0.053). The complication rate after repeat TACE was lower than after first TACE (p = 0.03). Median overall survival was similar after repeat (28.1 months) and first TACE (33.3 months) (p = 0.53). Progression-free survival was shorter after repeat TACE but not significantly so. No factor examined could predict
survival after repeat TACE.
Conclusion
Repeat TACE for patients with hepatic carcinoid metastases failing first TACE or having evidence of disease progression is
safe and offers a viable treatment option.
Presented at the 48th Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, DC, May, 2007. 相似文献
84.
Cholangiocarcinomas (CC) frequently demonstrate lymphatic spread. We investigated lymph node (LN) counts after resection of
extrahepatic CC and survival based on the SEER 1973–2004 database. Out of 20,068 CC patients, 1,518 individuals were selected
based on M0 stage and at least one LN examined. Primary cancer sites included gallbladder (29%), extrahepatic bile ducts (26%),
and intrapancreatic/ampullary bile ducts (45%); 42% of patients were LN-positive. The median number of LNs examined was four
(range 1–39). Median survival was 37 months for LN-negative and 16 months for LN-positive cancers. Multivariate prognostic
variables were the number of positive LNs, primary site, age (all at p < 0.0001), gender (p = 0.002), size (p = 0.005), T category (p = 0.009), and total LN count (or number of negative LNs obtained, p = 0.01). The impact of total LN counts was seen in LN-negative (median survival, 1 vs 10 or more LNs examined: 27 vs 51 months,
p = 0.002) and LN-positive disease (10 vs 22 months, p < 0.0001). Survival prediction of extrahepatic CCs is strongly influenced by total LN counts and numbers of negative LNs
obtained. Although the resulting incremental benefit is small, dissection and examination of 10 or more LNs should be considered
for curative intent resections. 相似文献
85.
86.
Introduction Choroid plexus cysts can lead to isolation of the lateral ventricles and distension of the third ventricle. We present an
ultrasonographic video documentation of an infant with variably shaped and localized choroid plexus cyst of the third ventricle.
Case report An infant had periods of increased intracranial pressure with changing dilatation of the first to third ventricle. Cerebral
ultrasonography of the not crying boy demonstrated a choroid plexus cyst limply hanging down from the roof of the third ventricle
to the beginning of the aqueduct of Sylvius. During crying, the cyst prolapsed from the third into left lateral ventricle
and was strangled by the foramen of Monro. Endoscopic cyst fenestration and third ventriculostomy continuously solved the
problem of intermittent hydrocephalus occlusus.
Conclusion Depending not only on localization and size but also on cyst form and cerebrospinal fluid pressure, a single choroid plexus
cyst can cause various obstructions of cerebrospinal fluid pathways. 相似文献
87.
Murat Hamit Aytar Fikret Doğulu Berker Cemil Ertan Ergün Gökhan Kurt Kemali Baykaner 《Child's nervous system》2007,23(6):719-721
Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine,
and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence.
This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as
anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders,
diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal
atresia.
Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term
survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think
that this patient presents a mild form of iniencephaly. 相似文献
88.
Ulrich Weber Christian WA Pfirrmann Rudolf O Kissling Juerg Hodler Marco Zanetti 《BMC musculoskeletal disorders》2007,8(1):20
Background
Ankylosing spondylitis is a chronic inflammatory rheumatic disorder which usually begins in early adulthood. The diagnosis is often delayed by many years. MR imaging has become the preferred imaging method for detection of early inflammation of the axial skeleton in ankylosing spondylitis. 相似文献89.
Oswens Siu Hung Lo Wai Lun Law Hok Kwok Choi Yee Man Lee Judy Wai Chu Ho Chi Leung Seto 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(2):173-178
OBJECTIVES: The study aimed to review the etiologies of patients who underwent surgery for small bowel obstruction (SBO) and to evaluate the risk factors affecting the early postoperative outcomes. MATERIALS AND METHODS: A case series of 430 patients (252 men) with a mean age of 64.5 years, who underwent 437 operations for SBO, were retrospectively reviewed. RESULTS: Peritoneal adhesions and hernia were the most common causes of SBO, contributing 42.3 and 26.8% of all cases, respectively. Strangulation occurred in 27.7% and caused nonviable bowel in 13.0% of obstructing episodes. Old age (age >/= 70 years), female patient, nonadhesive obstruction, and hernia were the independent significant factors associated with bowel strangulation. The 30-day mortality was 6.5%, and the median postoperative hospital stay was 8 days. Old age, the presence of premorbid pulmonary disease, and malignant obstruction were the independent factors associated with operative mortality. The overall complication rate was 35.5%, and old age was the only significant factor associated with postoperative complications. CONCLUSIONS: Surgery for SBO is still associated with significant mortality and morbidity. As old age is significantly associated with an increased incidence of strangulation, operative mortality, and complications, this group of patients should be managed with extra cautions to avoid unfavorable outcome of surgery. 相似文献
90.
Stefan Ockert Hardy Schumacher Dittmar Böckler Katrin Malcherek Jochen Hansmann Jens Allenberg 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):725-730
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic
aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares
the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA).
Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared
to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm
results were obtained through clinical investigation and magnetic resonance angiography imaging.
Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall
in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group
and 29 patients from the AAA group (82.9%) were alive.
Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate
without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms. 相似文献