全文获取类型
收费全文 | 5820篇 |
免费 | 266篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 76篇 |
妇产科学 | 33篇 |
基础医学 | 672篇 |
口腔科学 | 173篇 |
临床医学 | 373篇 |
内科学 | 1407篇 |
皮肤病学 | 130篇 |
神经病学 | 523篇 |
特种医学 | 141篇 |
外科学 | 1298篇 |
综合类 | 14篇 |
预防医学 | 162篇 |
眼科学 | 35篇 |
药学 | 403篇 |
中国医学 | 11篇 |
肿瘤学 | 634篇 |
出版年
2022年 | 48篇 |
2021年 | 69篇 |
2020年 | 40篇 |
2019年 | 60篇 |
2018年 | 81篇 |
2017年 | 61篇 |
2016年 | 80篇 |
2015年 | 79篇 |
2014年 | 88篇 |
2013年 | 133篇 |
2012年 | 230篇 |
2011年 | 261篇 |
2010年 | 159篇 |
2009年 | 132篇 |
2008年 | 244篇 |
2007年 | 273篇 |
2006年 | 298篇 |
2005年 | 237篇 |
2004年 | 239篇 |
2003年 | 241篇 |
2002年 | 194篇 |
2001年 | 238篇 |
2000年 | 246篇 |
1999年 | 250篇 |
1998年 | 60篇 |
1997年 | 51篇 |
1996年 | 71篇 |
1995年 | 55篇 |
1994年 | 62篇 |
1993年 | 37篇 |
1992年 | 157篇 |
1991年 | 168篇 |
1990年 | 129篇 |
1989年 | 164篇 |
1988年 | 159篇 |
1987年 | 148篇 |
1986年 | 117篇 |
1985年 | 121篇 |
1984年 | 74篇 |
1983年 | 57篇 |
1982年 | 29篇 |
1979年 | 42篇 |
1978年 | 27篇 |
1976年 | 30篇 |
1973年 | 24篇 |
1972年 | 27篇 |
1969年 | 37篇 |
1968年 | 27篇 |
1967年 | 33篇 |
1966年 | 23篇 |
排序方式: 共有6104条查询结果,搜索用时 15 毫秒
81.
Tc-99m colloid and Ga-67 imaging of splenic inflammatory pseudotumor correlation with ultrasound, CT, and MRI 总被引:2,自引:0,他引:2
Suga K Miura K Kume N Hara A Matsunaga N Tangoku A Oka M 《Clinical nuclear medicine》1999,24(5):334-337
Splenic inflammatory pseudotumor is extremely rare and may mimic splenic neoplasms, such as lymphomas or hamartomas, clinically and radiologically. A case of a surgically proved splenic inflammatory pseudotumor is presented in which Tc-99m colloid SPECT and Ga-67 scintigraphy characterized the changes in the spleen, but the findings of ultrasound and unenhanced CT and MRI were nonspecific. This report indicates the utility of radionuclide imaging for diagnosing splenic inflammatory pseudotumor. 相似文献
82.
In this paper we present a new technique for thymic cystectomy by video-assisted thoracic surgery. The thoracoscope was inserted using a Vein Harvest (Ethicon Endo-Surgery Co, Ltd, Cincinnati, OH) through a 5-cm subxyphoid incision. A Harmonic Scalpel (Ethicon Endo-Surgery) and Cherry Dissector (Ethicon Endo-Surgery) were used for dissection. The thymic cyst was successfully removed through the incision without thoracotomy. The advantage of this technique is that it is less invasive than video-assisted thoracic surgery through the thorax, removing the need for a thoracotomy. 相似文献
83.
We investigated age-related changes in the visibility of intracranial arteries on magnetic resonance angiography (MRA) and
the influence of risk factors for stroke. We studied 230 adult patients without specific neurological deficits. MRA was performed
using the three-dimensional time-of-flight technique with a spoiled gradient-recalled acquisition sequence. We classified
internal carotid artery (IC) and the horizontal (M1) and distal (beyond M2) middle cerebral segments into 4 grades. Linear
regression revealed a significant negative relation between age and the quality of demonstration on MRA. For IC and M1, the
score was significantly lower in subjects with risk factors than in those without. The distal MCA was poorly seen in patients
without a history of hypertension or lacunar infarcts. A marked correlation was observed between visibility and age patients
with no history of hypertension, diabetes mellitus and hyperlipidaemia. We suggest that atherosclerotic change and decline
in flow velocity with normal ageing are factors leading to decreased visibility on MRA.
Received: 13 January 1998 Accepted: 6 January 1999 相似文献
84.
Tsujimoto Y Oka T Noguchi T Fujii T Miyagawa Y Takano Y Yasunaga Y Takaha M Kanno N 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1999,90(12):920-923
A 32-year-old man consulted Osaka National hospital with chief complaints of dysuria and macrohematuria. DIP and CT revealed that the right kidney deviated to the lower pole of the left kidney and they fused together. The right ureter crossed over the supine. The calcified shadow existed in the lower end of the left ureter with cobra head image. He had no external anomalies. Under diagnosing crossed fused kidney (inverted L shaped) complicated the left ureterocele with a stone, transurethral incision of ureterocele (TUI) was performed. We made transverse incision and extracted stone, 7 mm in size (calcium oxalate 96% and calcium phosphate 4%). Three months later after the operation, IVP, CG and VCG revealed the down-sized ureterocele and no VUR. Crossed renal ectopia complicated many anomalies about 50%. Among them anomalies of the urinary tract was most frequent about 30%. But crossed renal ectopia with ureterocele wasn't reported so far in Japanese literature. 相似文献
85.
Yoshimura N Yamaguchi M Ohshima Y Oka S Ohtaki Y Murakami H Hasegawa T Shimazu C Ogawa K Tei T Kuroe K Kido S 《Kyobu geka. The Japanese journal of thoracic surgery》1999,52(4):286-289
From 1989, 4 patients underwent bilateral enlargement of the aortic valve ring for valve replacement. Age at the operation ranged from 2 to 8 (mean 6) years; body weight ranged from 14.9 to 25.4 (mean 19.0) kg. This procedure enabled us to implant a prosthesis 3 to 4 sizes larger (19 to 23 mm) than that measured with the native aortic annulus (13 to 17 mm). There was no late death and no cardiac event over a mean follow-up period of 6.2 years. Pressure gradient across the prosthesis measured by echocardiography was 40 mmHg in 1 patient who underwent aortic valve replacement with the use of 19 mm St. Jude Medical valve at 2 years of age. There was no significant pressure gradient in other 3 patients. All patients showed normal left ventricular function. We conclude that bilateral enlargement of the aortic valve ring for valve replacement has provided good midterm results with no mortality and no cardiac event. 相似文献
86.
Background: The usefulness of transthoracoscopic needle biopsy for preoperatively indeterminate intrapulmonary nodules was evaluated.
Methods: Thoracoscopy was performed on 38 patients with pulmonary solitary nodules suspected to be primary lung carcinomas. When the
nodule was localized by simple observation or tactile sensor, a biopsy specimen of the tumor was obtained by a biopsy needle
introduced through a trocar.
Results: The nodules were 7 to 55 mm in diameter. All were located in the peripheral region of the lung. Biopsy specimens were obtained
even from 17 nodules with no associated pleural changes. By cytology, all the malignant tumors were precisely diagnosed, 29
as primary lung cancers and 3 as metastatic lung neoplasms. Five of the remaining six benign nodules were not precisely diagnosed.
However, they were cytologically classified as class I.
Conclusions: Transthoracoscopic needle biopsy is feasible for diagnosing small intrapulmonary nodules, particularly those of malignant
neoplasms. As compared with thoracoscopic excisional biopsy, transthoracoscopic needle biopsy saves time and may reduce the
possibility of tumor dissemination during the procedure.
Received: 14 March 1997/Accepted: 31 May 1997 相似文献
87.
The present paper describes a new planar multielectrode array (the MED probe) and its electronics (the MED system) which perform electrophysiological studies on acute hippocampal slices. The MED probe has 64 planar microelectrodes, is covered with a non-toxic, uniform insulation layer, and is further coated with polyethylenimine and serum. The MED probe is shown to be appropriate for both stimulation and recording. In particular, multi-channel recordings of field EPSPs obtained by stimulating with a pair of planar microelectrodes were established for rat hippocampal acute slices. The recordings were stable for 6 h. Finally a spatial distribution of long-term potentiation was studied using the MED system. 相似文献
88.
Brains of thirteen patients with Fukuyama-type congenital muscular dystrophy (FCMD) were evaluated regarding the expression of cyclooxygenase 2 (COX2), an enzyme involved in the synthetic pathway of prostaglandins and thromboxanes, as well as neurofibrillary tangles (NFT). The neuronal induction of COX2 was demonstrated with immunohistochemistry and Western blotting confirmed the up-regulation. Preceded by COX2 immunoreactivity, NFT-containing neurons appeared in the majority of FCMD patients without beta-amyloid deposition or senile plaques. The hippocampus did not demonstrate neurodegeneration, while, in other areas, neurons with NFT spread in a similar manner to Alzheimer's disease. NFT-bearing neurons were concomitantly shown to be immunoreactive to COX2. The precedent induction of COX2, therefore, may be related to the formation of NFT in this genetic disorder. 相似文献
89.
Abe H Nishimura T Osawa S Hamasaki T Miura T Ikeda K Oka F Ohaki Y 《Urologia internationalis》1999,63(3):175-178
A method of multiple random biopsy combined with bladder wall aspiration and snare in bladder cancer is presented. Our method was used on 23 patients with clinically superficial bladder cancer and was found to have advantages in obtaining an adequate amount of tissue with minimal thermal degeneration. 相似文献
90.
Less invasive surgery for early gastric cancer based on the low probability of lymph node metastasis 总被引:32,自引:0,他引:32
BACKGROUND: Less invasive treatment is the current trend in many surgical fields. Most patients with early gastric cancer do not have lymph node metastasis. Thus extensive resection of the stomach and extended lymph node dissection do not appear to be necessary. METHODS: In a retrospective study, 890 consecutive patients with early gastric cancer who had undergone standard gastrectomy were assessed for depth of invasion, gross appearance, and maximum diameter of the tumor to examine the possibility of limiting the extent of lymph node dissection. A variety of limited gastrectomies have been developed and now include endoscopic mucosal resection, wedge resection, segmental gastrectomy, limited proximal gastrectomy, and distal hemigastrectomy. RESULTS: A retrospective study revealed that extensive lymph node dissection did not improve the survival of patients with early gastric cancer. Endoscopic mucosal resection was suitable for cancers of the depressed type of less than 1 cm in diameter and the elevated type of less than 2 cm in diameter. Wedge, segmental, or limited proximal gastrectomy was suitable for the elevated type of 2 to 3 cm in diameter. The elevated type of more than 3 cm in diameter and the depressed type of 1 to 3 cm in diameter sometimes involved metastasis to group 1 nodes. The depressed type of more than 3 cm in diameter sometimes involved metastasis to group 2 nodes. Thus such cases should be treated by gastrectomy with dissection of potentially metastatic lymph nodes. CONCLUSIONS: Limitation of the extent of gastrectomy and lymph node dissection may be possible, depending on the gross appearance and size of the tumor. 相似文献