全文获取类型
收费全文 | 8287篇 |
免费 | 392篇 |
国内免费 | 62篇 |
专业分类
耳鼻咽喉 | 85篇 |
儿科学 | 143篇 |
妇产科学 | 87篇 |
基础医学 | 1089篇 |
口腔科学 | 131篇 |
临床医学 | 525篇 |
内科学 | 2207篇 |
皮肤病学 | 84篇 |
神经病学 | 717篇 |
特种医学 | 270篇 |
外科学 | 1353篇 |
综合类 | 32篇 |
预防医学 | 245篇 |
眼科学 | 116篇 |
药学 | 735篇 |
中国医学 | 33篇 |
肿瘤学 | 889篇 |
出版年
2023年 | 22篇 |
2022年 | 61篇 |
2021年 | 102篇 |
2020年 | 49篇 |
2019年 | 88篇 |
2018年 | 103篇 |
2017年 | 102篇 |
2016年 | 119篇 |
2015年 | 138篇 |
2014年 | 145篇 |
2013年 | 222篇 |
2012年 | 324篇 |
2011年 | 354篇 |
2010年 | 239篇 |
2009年 | 203篇 |
2008年 | 319篇 |
2007年 | 394篇 |
2006年 | 392篇 |
2005年 | 401篇 |
2004年 | 388篇 |
2003年 | 412篇 |
2002年 | 432篇 |
2001年 | 325篇 |
2000年 | 347篇 |
1999年 | 346篇 |
1998年 | 112篇 |
1997年 | 94篇 |
1996年 | 81篇 |
1995年 | 87篇 |
1994年 | 94篇 |
1993年 | 99篇 |
1992年 | 238篇 |
1991年 | 251篇 |
1990年 | 218篇 |
1989年 | 202篇 |
1988年 | 205篇 |
1987年 | 172篇 |
1986年 | 185篇 |
1985年 | 144篇 |
1984年 | 97篇 |
1983年 | 76篇 |
1982年 | 46篇 |
1981年 | 30篇 |
1980年 | 28篇 |
1979年 | 79篇 |
1978年 | 37篇 |
1977年 | 26篇 |
1976年 | 22篇 |
1975年 | 12篇 |
1969年 | 10篇 |
排序方式: 共有8741条查询结果,搜索用时 0 毫秒
101.
Decay-accelerating factor induction by tumour necrosis factor-alpha, through a phosphatidylinositol-3 kinase and protein kinase C-dependent pathway, protects murine vascular endothelial cells against complement deposition 总被引:2,自引:0,他引:2 下载免费PDF全文
Ahmad SR Lidington EA Ohta R Okada N Robson MG Davies KA Leitges M Harris CL Haskard DO Mason JC 《Immunology》2003,110(2):258-268
102.
Maeno N Kusunoki K Kitajima T Iwata N Ono Y Hashimoto S Imai M Li L Kayukawa Y Ohta T Ozaki N 《Journal of affective disorders》2005,85(3):267-273
BACKGROUND: Although there have been numerous reports in personality of mood disorders, there have been few reports in regard with personality of winter seasonal affective disorder (SAD). Furthermore, no reports have been published concerning summer SAD personality characteristics. Thus, this study was conducted to assess the personality of winter and summer SAD using Tri-dimensional Personality Questionnaire (TPQ) that have been used in a variety of mental disorders. METHODS: A total of 6135 Japanese were evaluated with TPQ, the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Self-rating Depression Scale (SDS). Winter, summer and non-SAD groups were classified by SPAQ. We compared the difference of personality trait among these three groups in consideration of gender, age and SDS score influence. RESULTS: Winter SAD demonstrated higher "Novelty Seeking" and "Harm Avoidance"; summer SAD showed higher "Harm Avoidance" than the non-SAD group. "Harm Avoidance" in both SAD groups was re-analyzed using SDS score as a covariate, and "Novelty Seeking" in winter SAD using age as a covariate. As a result, the significance of high "Novelty Seeking" and high "Harm Avoidance" in winter SAD was excluded. However, "Harm Avoidance" remained the significant difference between summer and non-SAD. LIMITATION: SAD was diagnosed only by SPAQ and not by interview. The state-dependency of "Harm Avoidance" was not confirmed in identical patients over lapse of time. CONCLUSION: Patients with winter SAD have high "Harm Avoidance" dependent on the depressive state that is in accordance with non-seasonal depression. Patients with summer SAD have high "Harm Avoidance" possibly independent from the depressive state. 相似文献
103.
Twenty-six patients with the clinical and histologic diagnosis of primary biliary cirrhosis were reviewed. Nodular hyperplasia of the liver without fibrous rims, not reported hitherto in patients with primary biliary cirrhosis, was found in several patients with early histological stages. These changes resembled "nodular regenerative hyperplasia of the liver" and were usually present as multicellular thickness in zones 1 and 2 of the hepatic lobules. Such lesions were preferentially found in patients with esophageal varices, suggesting that the nodular hyperplasia may occur in relation to a disturbance of portal venous blood flow within the liver in primary biliary cirrhosis in early histological stages. 相似文献
104.
Kiyoji Kimura Ryuzo Ohno Ichita Amaki Kenichi Hattori Yutaka Hirota Akira Hoshino Michito Ichimaru Munemoto Ito Ikuo Kimura Tadashi Maekawa Toru Masaoka Toru Nakamura Makoto Ogawa Masao Oguro Kazuo Ohta Shigeyuki Osamura Masanori Shimoyama Fumimaro Takaku Yoshiro Uzuka Kazumasa Yamada 《Medical oncology (Northwood, London, England)》1986,3(1):15-24
A phase I study ofN 4-behenoyl-1-β-d-arabinofuranosylcytosine (BHAC) was conducted in 66 patients, 41 with solid tumors and 25 with hematological malignancies. The patients received either a 2-h single intravenous (i.v.) drip infusion (Schedule 1) or consecutive daily 2-h i.v. infusions (Schedule 2). In Schedule 1 the daily dose was initiated with 1.5 mg kg?1 which was escalated up to 7 mg kg?1. Side-effects were mild, and included nausea, vomiting, epilation, and hot flushes. Because of the presence of the solvent vehicle, HCO-60 and in consideration of the mechanism of action of BHAC, the dose escalation was stopped at 7 mg kg?1. In Schedule 2, the daily dose was started with 1.5 mg kg?1 which was escalated up to 8 mg kg?1 and given for 2–16 days. Myelosuppression was found to be dose-limiting toxicity. The maximum tolerated dose (MTD) in patients with non-hematological solid tumors was assumed to be 5 mg kg?1 daily × 5 days. The plasma disappearance curve of BHAC looked biphasic, and when 4 mg kg?1 of BHAC were administered the half-lives of the initial phase (t 1/2α) and the second phase (t 1/2β) were calculated as 0.798 and 5.76 h respectively. In Schedule 2 complete remission was observed in 5 out of 21 patients with acute leukemia, one partial remission in Hodgkin’s disease, and one 1-B response (Karnofsky) in thyroid papillary adenocarcinoma. 相似文献
105.
Takanori Abe Satoshi Saito Misaki Iino Tomomi Aoshika Yasuhiro Ryuno Tomohiro Ohta Mitsunobu Igari Ryuta Hirai Yu Kumazaki Yasuhiro Ebihara Mitsuhiko Nakahira Masashi Sugasawa Shin-ei Noda Shingo Kato 《Journal of radiation research》2021,62(1):104
The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study. 相似文献
106.
Masayuki Takeda Yasushi Katayama Toshiki Tsutsui Hitoshi Takahashi Kazuhide Saito Shotaro Sato Tatsuhiko Yuasa Takeo Kuwabara 《Urological research》1993,21(3):193-197
Summary
31P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed.31P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the31P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of -ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than -ATP and Pi. In conclusion, according to the findings of31P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and -ATP should be examined further. 相似文献
107.
H Ohta 《Neurologia medico-chirurgica》1990,30(1):16-23
Cerebral blood flow (CBF) was measured in 90 patients who underwent early aneurysmal clipping after subarachnoid hemorrhage (SAH). Measurements were made by a noninvasive, two-dimensional method involving intravenous injection of 133Xe. Patients of Hunt and Hess grades I and II exhibited normal to slightly subnormal CBF, without significant changes, during the study period. Grades III-V patients had almost normal CBF in the early postoperative period, but their CBF gradually decreased, becoming significantly low after day 31. It is noteworthy that in grades IV and V patients, CBF was abnormally high in the acute stage, relative to their poor neurological condition; these patients were considered to have the "global luxury perfusion syndrome." The syndrome was not uncommon in patients with severe SAH. Possible causative or contributory factors are attempts to surgically reduce intracranial pressure, which leads to increased cerebral perfusion pressure, and concomitant global dysautoregulation. In patients with this syndrome, maneuvers intended to increase CBF should be avoided, as they may aggravate brain swelling or cause hemorrhagic events. Positron emission tomographic studies will provide more accurate and useful information concerning the management of SAH patients. 相似文献
108.
K Yoshida R Abe S Itoh T Taguchi J Ohta T Morimoto T Ishida H Tashiro M Ogita C Kido 《Japanese journal of clinical oncology》1990,20(4):374-379
In a nation-wide collaborative study on mass screening for breast cancer, we collected 152 cases of interval breast cancer diagnosed at 35 hospitals or clinics distributed throughout Japan. The definition of interval breast cancer used in the present study is "breast cancer cases which were diagnosed as having 'no malignant findings' in a previous screening for breast cancer but subsequently diagnosed as 'breast cancer' at a hospital or medical clinic within two years of the previous screening." The clinical stages and prognoses of these interval cancer were analyzed and compared with those of other breast cancers detected through mass screening and in outpatient clinics. In the clinical staging of interval breast cancer, Tis (non infiltrating cancer) accounted for only 2.1%, compared to 8.0% in cases detected through mass screening. At stage I 43.4% were interval breast cancers compared to 32.9% breast cancers detected through mass screening and 25.4% diagnosed in outpatient clinics. The stage differences between interval breast cancers and breast cancers detected through mass screening were not statistically significant. Five-year survival rates were 85.6% for interval breast cancers, 91.7% for breast cancers detected through mass screening and 84.7% for breast cancers diagnosed in outpatient clinics. Ten-year survival rates were 75.9, 80.5 and 78.1%, respectively, suggesting the interval breast cancer cases to show a similar prognosis to that of breast cancer cases diagnosed in outpatient clinics. The differences in five- and 10-year survival rates among the three groups were not statistically significant. From the present study we were not able to confirm the general belief of interval cancer being more aggressive in nature and showing a poorer prognosis than cancer detected through periodic screening. The reasons for this are discussed. 相似文献
109.
Ohta T Fukuda M Arima K Kawamoto H Hashizume R Arimura T Yamaguchi S 《Breast cancer (Tokyo, Japan)》1997,4(1):17-24
Cyclins and cyclin-dependent kinases may reflect the status of cell proliferation in cancer tissues. The authors sought to
determine whether cdc2 and cyclin D1 are expressed in breast cancer and are useful as prognostic factors. Accumulation of
cdc2 and cyclin D1 proteins was examined in 88 cases of breast cancer using immunoblotting techniques and correlations with
clinicopathological factors and prognoses were investigated. Cdc2 and cyclin D1 proteins were observed in 27.3% and 75.0%
of breast cancers studied, respectively. The incidence of lymph node metastasis was significantly high in cdc2/cyclin D1-double
positive group and low in double negative group. On the other hand, the incidence of estrogen receptor (ER) negative cases
was significantly higher in the cdc2-positive/cyclin D1-negative group. Relapse-free survival times of cdc2-positive cases
were significantly shorter than those of cdc2-negative cases. The relapse-free survival times of cyclin D1-positive cases
also tended to be poorer than those of cyclin D1-negative cases. Multivariate analyses revealed cdc2 as the second most significant
of the prognostic variables, following lymph node status. The three-year relapse-free survival rate of cdc2/cyclin D1-double
positive cases was 58.9%, whereas that of cdc2/cyclin D1-double negative cases was 100%. Cdc2 and cyclin D1 represent the
status of cell proliferation in breast cancer, and may be useful in breast cancer assessment. 相似文献
110.
We employed immunohistochemical methods to investigate the overexpression of cyclin D1 protein as well as p53 protein and retinoblastoma protein (pRb) in 57 patients with transitional cell carcinoma (TCC) of the urinary tract, in order to determine their frequency and significance, and also association with the clinicopathological behavior of this tumor. Nuclear immunostaining with cyclin D1 antibody revealed 7 homogeneously stained tumors (12.3%), including 4 heterogeneous pRb expressions, of which only one was also positive for p53. Positive immunostaining with each antibody to p53 or pRb was obtained in 15 (26.3%) and 49 (86%) tumors, respectively. The 49 pRb-positive tumors included 6 homogeneous and 43 heterogeneous nuclear immunostaining patterns. The remaining pRb-negative 8 tumors included 5 cyclin D1-negative tumors. The prevalence of p53 staining was higher in high-grade (P<0.05) and invasive types of tumors (P<0.05) than the other types studied. On the other hand, no significant relationship was found between cyclin D1- or pRb-immunoreactivity and clinicopathological factors. These findings provide evidence for infrequent cyclin D1 protein overexpression in TCC independently associated with p53 protein and/or pRb overexpression. 相似文献