全文获取类型
收费全文 | 7910篇 |
免费 | 420篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 150篇 |
儿科学 | 174篇 |
妇产科学 | 94篇 |
基础医学 | 972篇 |
口腔科学 | 314篇 |
临床医学 | 457篇 |
内科学 | 2009篇 |
皮肤病学 | 217篇 |
神经病学 | 728篇 |
特种医学 | 213篇 |
外科学 | 1162篇 |
综合类 | 47篇 |
一般理论 | 1篇 |
预防医学 | 230篇 |
眼科学 | 70篇 |
药学 | 582篇 |
中国医学 | 18篇 |
肿瘤学 | 941篇 |
出版年
2023年 | 64篇 |
2022年 | 116篇 |
2021年 | 186篇 |
2020年 | 108篇 |
2019年 | 119篇 |
2018年 | 160篇 |
2017年 | 117篇 |
2016年 | 146篇 |
2015年 | 133篇 |
2014年 | 177篇 |
2013年 | 232篇 |
2012年 | 327篇 |
2011年 | 342篇 |
2010年 | 212篇 |
2009年 | 163篇 |
2008年 | 308篇 |
2007年 | 362篇 |
2006年 | 357篇 |
2005年 | 404篇 |
2004年 | 358篇 |
2003年 | 364篇 |
2002年 | 344篇 |
2001年 | 297篇 |
2000年 | 257篇 |
1999年 | 240篇 |
1998年 | 120篇 |
1997年 | 82篇 |
1996年 | 78篇 |
1995年 | 79篇 |
1994年 | 71篇 |
1993年 | 61篇 |
1992年 | 185篇 |
1991年 | 151篇 |
1990年 | 176篇 |
1989年 | 145篇 |
1988年 | 144篇 |
1987年 | 156篇 |
1986年 | 121篇 |
1985年 | 136篇 |
1984年 | 96篇 |
1983年 | 75篇 |
1982年 | 40篇 |
1980年 | 42篇 |
1979年 | 65篇 |
1978年 | 39篇 |
1977年 | 40篇 |
1975年 | 38篇 |
1974年 | 43篇 |
1972年 | 34篇 |
1971年 | 34篇 |
排序方式: 共有8379条查询结果,搜索用时 15 毫秒
131.
The increase of cardiac beta 1-subtype of beta-adrenergic receptors in adult rats following neonatal 6-hydroxydopa treatment 总被引:1,自引:0,他引:1
An analysis of Hofstee plots of specific [3H]dihydroalprenolol ([3H]DHA) binding in the presence of various concentrations of practolol showed that KD and Bmax in beta 1-subtype adrenoceptors were 19.2-fold lower and 2.76-fold higher than those in beta 2-subtype in adult rat hearts, respectively. Neonatal treatment with 6-hydroxydopa produced a significant increase only in Bmax in beta 1-adrenoceptors without changing Bmax and KD in beta 2-receptors. "Up' regulation in the density of beta 2-type of adrenoceptors seems to be caused by the 6-hydroxydopa-induced sympathetic lesion. 相似文献
132.
133.
We sought to determine whether a selection process for deployment had a measurable effect on psychological symptoms by comparing scores on the Yatabe-Guilford Personality Index, the Manifest Anxiety Scale, and the 30-item version of the General Health Questionnaire between deployed and nondeployed mission candidates from the Japan Self-Defense Forces. The studies were undertaken in Japan during education and training for the United Nations peacekeeping mission in the Golan Heights. The participants included 80 candidates for deployment. Personnel who were not deployed had significantly higher measures of manifest anxiety and general psychological distress than deployed personnel, whereas deployed personnel showed more symptoms suggesting somatization. The selection process and training for deployment appear to have been stressful for all personnel, whether deployed or not. 相似文献
134.
The efficacy of the McCoy laryngoscope, external laryngeal pressure, and their combination to improve the laryngoscopic view was evaluated in 219 patients and compared with the Macintosh laryngoscope. An experienced laryngoscopist performed laryngoscopy twice using the Macintosh laryngoscope and the McCoy laryngoscope in a random sequence, and external laryngeal pressure was applied in each laryngoscopy with the laryngoscopist's right hand. The laryngoscopic view obtained was graded on our modified Cormack's method. Without external laryngeal pressure, the McCoy laryngoscope provided a better laryngoscopic view than that obtained by the Macintosh laryngoscope (P < 0.001, signed rank test), but the view was worse than that with the Macintosh laryngoscope under external laryngeal pressure (P < 0.001). The McCoy laryngoscope combined with external laryngeal pressure provided a better view than the Macintosh laryngoscope with external laryngeal pressure (P < 0.001). 相似文献
135.
Nomura M Kida S Kita D Kaneko T Higashi R Yoshikawa J Matsui O Yamashita J 《Surgical neurology》2000,53(3):239-242
BACKGROUND: We present a case of ruptured vertebral dissecting aneurysm that exhibited cerebellar hemorrhage after successful embolization of the vertebral artery including the dissected site. CASE PRESENTATION: A 59-year-old man suffered a sudden onset of severe occipital headache when he looked up. Computed tomography demonstrated subarachnoid hemorrhage. Angiography revealed a right vertebral dissecting aneurysm distal to the posterior inferior cerebellar artery. Endovascular embolization of the aneurysm was performed with preservation of the posterior inferior cerebellar artery. The next day, the patient suffered a cerebellar hemorrhage in the vermis. The intracranial pressure was controlled by external ventricular drainage. The patient was discharged with mild cerebellar ataxia and bilateral abducens nerve palsy. CONCLUSION: In a case of vertebral dissecting aneurysm distal to the posterior inferior cerebellar artery, blood circulation in the vertebral arterial system may change after embolization of the aneurysm. In our case, the preserved posterior inferior cerebellar artery might have been hemodynamically stressed postoperatively, resulting in cerebellar hemorrhage. Therefore, strict control of blood pressure is essential in the acute stage after occlusion of the aneurysm. 相似文献
136.
Takeshi Tominaga Hiroki Koyama Tetsuya Toge Shigeto Miura Keizo Sugimachi Susumu Yamaguchi Koichi Hirata Yasumasa Monden Yasuo Nomura Masakazu Toi Izo Kimijima Shinzaburo Noguchi Hiroshi Sonoo Kazuaki Asaishi Tadashi Ikeda Tadaoki Morimoto Jun Ota Yasuo Ohashi Osahiko Abe 《Journal of clinical oncology》2003,21(6):991-998
PURPOSE: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy. PATIENTS AND METHODS: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups. RESULTS: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001). CONCLUSION: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone. 相似文献
137.
138.
Since the first treatment of acoustic neurinoma using the γ-knife by Leksell, a series of cases have been reported with good control rates. However, the most frequent complication is delayed hearing loss which occurs in more than 50% of patients. The purpose of this study was to define a safe dose by analyzing the radiosurgical dose-response relationship and histological effects on the normal cochlear nerve in rabbit. The rabbits had computed tomography (CT)-guided stereotactic radiosurgery on their cochlear nerves in the internal auditory canal with a 4 mm collimator focusing of a γ-unit. Maximum doses of 10, 20, 30, 40, 60, 80, 100, 200 and 500 Gy were administered. After the radiosurgery, auditory brain stem responses (ABR) and the behavior of the rabbits were evaluated periodically. At the conclusion, histological investigations were performed. No physiological or histological findings were observed from doses of 30 Gy or below during the 12 month period after the radiosurgery. A dose of 100 Gy caused a severe ABR threshold elevation, vestibular dysfunction and facial palsy. Necrosis and demyelination of nerves were observed pathologically. In this study, we determined that the safe dose to the normal cochlear nerve during radiosurgery was under 40 Gy in rabbits, and complications seemed to vary due to individual differences in radiation tolerance. 相似文献
139.
Kolonel LN Henderson BE Hankin JH Nomura AM Wilkens LR Pike MC Stram DO Monroe KR Earle ME Nagamine FS 《American journal of epidemiology》2000,151(4):346-357
The authors describe the design and implementation of a large multiethnic cohort established to study diet and cancer in the United States. They detail the source of the subjects, sample size, questionnaire development, pilot work, and approaches to future analyses. The cohort consists of 215,251 adult men and women (age 45-75 years at baseline) living in Hawaii and in California (primarily Los Angeles County) with the following ethnic distribution: African-American (16.3%), Latino (22.0%), Japanese-American (26.4%), Native Hawaiian (6.5%), White (22.9%), and other ancestry (5.8%). From 1993 to 1996, participants entered the cohort by completing a 26-page, self-administered mail questionnaire that elicited a quantitative food frequency history, along with demographic and other information. Response rates ranged from 20% in Latinos to 49% in Japanese-Americans. As expected, both within and among ethnic groups, the questionnaire data show substantial variations in dietary intakes (nutrients as well as foods) and in the distributions of non-dietary risk factors (including smoking, alcohol consumption, obesity, and physical activity). When compared with corresponding ethnic-specific cancer incidence rates, the findings provide tentative support for several current dietary hypotheses. As sufficient numbers of cancer cases are identified through surveillance of the cohort, dietary and other hypotheses will be tested in prospective analyses. 相似文献
140.
Kataoka T; Haruta R; Goto T; Sugino K; Asahara T; Dohi K; Kaneco M; Arihiro K; Nomura S 《Japanese journal of clinical oncology》1998,28(4):276-280
A surgically resected case of giant malignant phyllodes tumor of the breast
associated with a hypoglycemic attack is reported. A 54-year-old woman was
referred to our hospital with loss of consciousness and a huge chest wall
tumor. She was diagnosed as having a malignant phyllodes tumor by core
needle biopsy and underwent palliative simple mastectomy because lung
metastasis was detected on computed tomography and by other imaging
modalities on admission. The preoperative laboratory data revealed a very
low fasting blood sugar level of 37 mg/dl. After removal of the tumor, the
blood sugar level gradually normalized (90-100 mg/dl) and the plasma
insulin-like growth factor-II (IGF-II) level promptly decreased. The IGF-II
level of tumor extracts was high (2500 ng/g wet weight) and the majority of
atypical cells stained positively for IGF-II immunohistochemically. These
findings suggested that the patient's hypoglycemia was associated with
IGF-II produced by a giant malignant phyllodes tumor that consumed glucose.
相似文献