全文获取类型
收费全文 | 4441篇 |
免费 | 244篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 65篇 |
妇产科学 | 34篇 |
基础医学 | 524篇 |
口腔科学 | 137篇 |
临床医学 | 286篇 |
内科学 | 1402篇 |
皮肤病学 | 42篇 |
神经病学 | 254篇 |
特种医学 | 210篇 |
外科学 | 761篇 |
综合类 | 15篇 |
预防医学 | 70篇 |
眼科学 | 91篇 |
药学 | 281篇 |
中国医学 | 6篇 |
肿瘤学 | 515篇 |
出版年
2024年 | 3篇 |
2023年 | 27篇 |
2022年 | 62篇 |
2021年 | 108篇 |
2020年 | 65篇 |
2019年 | 82篇 |
2018年 | 110篇 |
2017年 | 69篇 |
2016年 | 111篇 |
2015年 | 112篇 |
2014年 | 151篇 |
2013年 | 192篇 |
2012年 | 258篇 |
2011年 | 292篇 |
2010年 | 176篇 |
2009年 | 125篇 |
2008年 | 297篇 |
2007年 | 286篇 |
2006年 | 292篇 |
2005年 | 304篇 |
2004年 | 299篇 |
2003年 | 282篇 |
2002年 | 291篇 |
2001年 | 66篇 |
2000年 | 66篇 |
1999年 | 63篇 |
1998年 | 75篇 |
1997年 | 53篇 |
1996年 | 61篇 |
1995年 | 33篇 |
1994年 | 50篇 |
1993年 | 39篇 |
1992年 | 40篇 |
1991年 | 32篇 |
1990年 | 27篇 |
1989年 | 19篇 |
1988年 | 15篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1919年 | 1篇 |
排序方式: 共有4706条查询结果,搜索用时 0 毫秒
1.
2.
Shuichi Kuniyuki 《The Journal of dermatology》1997,24(2):120-124
A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist. 相似文献
3.
Shuichi Sato Fumiko Nasu Katsutoshi Motegi 《Journal of oral and maxillofacial surgery》2002,60(8):867-872
PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously. 相似文献
4.
Hiromitsu Nakaya Shuichi Kawashiri Akira Tanaka Natsuyo Noguchi Koroku Kato Takashi Hase Etsuhide Yamamoto 《Journal of oral pathology & medicine》2005,34(2):87-92
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion. 相似文献
5.
Usefulness of leg-crossing for maintaining blood pressure in a sitting position in patients with orthostatic hypotension--case reports 总被引:1,自引:0,他引:1
The authors report a case with idiopathic orthostatic hypotension in which the patient prevents his blood pressure from falling to a symptomatic level by leg-crossing in a sitting position. Including 4 other patients with orthostatic hypotension and 5 normal subjects, their study found that the changes in blood pressure with leg-crossing inversely correlated with those induced by assuming seated posture from a supine position. Leg-crossing may, therefore, be one of the useful nonpharmacologic measures for maintaining blood pressure in a sitting position in patients with orthostatic hypotension. 相似文献
6.
Comparison of p53 expression in proximal and distal gastric cancer: Histopathologic correlation and prognostic significance 总被引:2,自引:0,他引:2
Huihuan Tang MD Shuichi Hokita MD PhD Xiangming Che MD Masamichi Baba MD PhD Kuniaki Aridome MD PhD Fumio Kijima MD Gen Tanabe MD PhD Sonshin Takao MD PhD Dr. Takashi Aikou MD PhD 《Annals of surgical oncology》1997,4(6):470-474
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but
no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53
expression of proximal and distal gastric cancer concerning histopathology and prognosis.
Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical
methods.
Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher
than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference
between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology
of gastric cancer.
Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer. 相似文献
7.
Shuichi Umeoka Koichi Baba Kiyohito Terada Kazumi Matsuda Takayasu Tottori Naotaka Usui Keiko Usui Fumihiro Nakamura Yushi Inoue Tateki Fujiwara Tadahiro Mihara 《Epileptic Disord》2007,9(4):443-448
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences]. 相似文献
8.
Shuichi Takishita Hiromi Muratani Hiroshi Teruya Shogo Sesoko Koshiro Fukiyama 《Clinical and experimental nephrology》1997,1(4):261-265
Background Stressful psychological stimuli produce an increase in renal sympathetic nerve activity (RSNA) and a decrease in renal blood
flow. Very few direct analyses of the relationship between RSNA and renal blood flow during the application of psychological
stimuli have been conducted by recording these 2 measurements simultaneously in the same individual animals.
Methods We simultaneously measured RSNA and renal blood flow as a Doppler shift in conscious, unrestrained, spontaneously hypertensive
rats. The rats were stressed by directing a continuous air jet at their faces for 20 seconds.
Results Air-jet stimulus increased RSNA 81%±15% (mean±standard error of the mean, n=10), mean arterial pressure (21±3 mm Hg), and
renal vascular resistance (37%±6%), and decreased renal blood flow (−15%±2%). The percentage change in RSNA correlated positively
with the change in mean arterial pressure (r=0.934,P<0.001) and percentage change in renal vascular resistance (r=0.912), and negatively with the percentage change in renal blood flow (r=−0.804). The denervation of renal nerves prevented renal blood flow from decreasing in response to air-jet stress.
Conclusions A reduction in renal blood flow in response to short-term air-jet stress is elicited mainly by neural mechanisms in spontaneously
hypertensive rats. Enhancement of RSNA by air-jet stimulus exerts a potent constricting effect on the renal vascular bed,
resulting in a reduction in renal blood flow. 相似文献
9.
Sumiya Ishigami Shuichi Hokita Shoji Natsugoe Masahiro Tokushige Tetsushi Saihara Hirohumi Iwashige Kuniaki Aridome Takashi Aikou 《World journal of surgery》1998,22(10):1056-1060
n
= 25) and node-negative (
n
= 81) groups. Among several pathologic factors, the diameter of the tumor and lymphatic involvement were significantly correlated
with nodal involvement. Within the submucosal layer the depth of invasion and the horizontal cancerous expansion also correlated
with lymph node disease (
p
< 0.05). The size of the tumor did not correlate with the length of submucosal infiltration (
r
= 0.12,
p
= 0.1). Patients with both slight invasion into the submucosa and less than 5 mm of horizontal expansion were often negative
for lymph node involvement and thus may benefit from local surgery as an alternative to gastrectomy. 相似文献
10.
Seiji Kinugasa Shuichi Tachibana Manpei Kawakami Tatsuhiko Orino Ryuichi Yamamoto Shinjiro Sasaki 《Surgery today》1998,28(3):335-338
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997) 相似文献