全文获取类型
收费全文 | 403篇 |
免费 | 16篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 13篇 |
妇产科学 | 8篇 |
基础医学 | 25篇 |
口腔科学 | 8篇 |
临床医学 | 61篇 |
内科学 | 76篇 |
皮肤病学 | 2篇 |
神经病学 | 18篇 |
特种医学 | 88篇 |
外科学 | 48篇 |
综合类 | 7篇 |
预防医学 | 11篇 |
眼科学 | 7篇 |
药学 | 30篇 |
肿瘤学 | 11篇 |
出版年
2022年 | 2篇 |
2021年 | 9篇 |
2019年 | 8篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 10篇 |
2014年 | 18篇 |
2013年 | 14篇 |
2012年 | 14篇 |
2011年 | 12篇 |
2010年 | 17篇 |
2009年 | 12篇 |
2008年 | 10篇 |
2007年 | 8篇 |
2006年 | 24篇 |
2005年 | 24篇 |
2004年 | 13篇 |
2003年 | 12篇 |
2002年 | 8篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 16篇 |
1997年 | 13篇 |
1996年 | 16篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 15篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 11篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 9篇 |
1984年 | 2篇 |
1983年 | 6篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有424条查询结果,搜索用时 15 毫秒
1.
Parasternal mediastinal sonography: sensitivity in the detection of anterior mediastinal and subcarinal tumors 总被引:1,自引:0,他引:1
Twenty-seven patients with anterior mediastinal and subcarinal mediastinal tumors confirmed by CT and 30 control subjects were prospectively investigated by sonography performed via a parasternal approach in both decubitus positions. The sonograms and CT scans were interpreted blindly by two investigators and the results of the two procedures were compared. In the group of 30 controls, sonography via the right parasternal approach showed the anterior mediastinum in 29 (97%) and the subcarinal space in 27 (90%). Fifteen (94%) of 16 anterior mediastinal tumors and 16 (94%) of 17 subcarinal tumors were identified sonographically. These results show that parasternal sonography is a sensitive technique for the detection of tumors in the anterior mediastinal and subcarinal mediastinal spaces. 相似文献
2.
3.
Image-directed percutaneous biopsies with a biopsy gun 总被引:3,自引:0,他引:3
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献
4.
K Wernecke 《R?ntgen-Bl?tter; Zeitschrift für R?ntgen-Technik und medizinisch-wissenschaftliche Photographie》1989,42(9):378-383
From an overall point of view sonographic diagnostics of tumours of the liver is characterised by a high degree of sensitivity. Although an approximate differentiation between benign and malignant tumours is possible, it is not sufficiently reliable. Compared with the often monotonous CT imaging of liver tumours, the extremely "colourful" sonographic image (which seems to be full of "variety of species") of lesions of the liver supplies decisive pointers, so that the range of tumours to be considered in differential diagnosis becomes more limited. Such preselection is important especially for the choice of further measures to confirm the diagnosis. Sonographic differentiation between primary and secondary liver tumours is uncertain, and hence histological verification is mandatory. In what way sonography can help to determine whether a tumour is operable or not, has not yet been studied and is therefore by no means clear. Sonography is highly sensitive in the detection of tumours of the pancreas, especially with minor lesions of less than 2 cm diameter. The sonographic image of the adenocarcinoma is non-specific, so that it must be considered imperative to clarify by histological examination even extensive findings that appear totally inoperable, so that a distinction can be made against tumours of the pancreas which have a better prognosis. Sonographic assessment of whether or not a tumour can be resected can only be effected in a negative sense if there are unequivocal sonographic criteria proving that the tumour is inoperable. 相似文献
5.
6.
7.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
8.
Role of epidural medication through caudal route was studied in 109 patients having lumbago with or without sciatica to highlight the value of this mode of treatment which relieved symptoms in more than 70% of cases without hospitalisation and without being off work for long periods as in usual methods of conservative treatment.KEY WORDS: Epidural medication, Backache, Lumbago, Sciatica 相似文献
9.
10.
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures. 相似文献