全文获取类型
收费全文 | 6643篇 |
免费 | 401篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 170篇 |
妇产科学 | 144篇 |
基础医学 | 1032篇 |
口腔科学 | 134篇 |
临床医学 | 473篇 |
内科学 | 1654篇 |
皮肤病学 | 265篇 |
神经病学 | 585篇 |
特种医学 | 167篇 |
外科学 | 587篇 |
综合类 | 29篇 |
预防医学 | 347篇 |
眼科学 | 159篇 |
药学 | 542篇 |
中国医学 | 24篇 |
肿瘤学 | 693篇 |
出版年
2024年 | 4篇 |
2023年 | 45篇 |
2022年 | 115篇 |
2021年 | 175篇 |
2020年 | 98篇 |
2019年 | 183篇 |
2018年 | 178篇 |
2017年 | 149篇 |
2016年 | 172篇 |
2015年 | 185篇 |
2014年 | 244篇 |
2013年 | 302篇 |
2012年 | 502篇 |
2011年 | 516篇 |
2010年 | 291篇 |
2009年 | 255篇 |
2008年 | 414篇 |
2007年 | 471篇 |
2006年 | 482篇 |
2005年 | 483篇 |
2004年 | 443篇 |
2003年 | 383篇 |
2002年 | 409篇 |
2001年 | 60篇 |
2000年 | 39篇 |
1999年 | 58篇 |
1998年 | 77篇 |
1997年 | 60篇 |
1996年 | 51篇 |
1995年 | 36篇 |
1994年 | 39篇 |
1993年 | 26篇 |
1992年 | 14篇 |
1991年 | 17篇 |
1990年 | 17篇 |
1989年 | 14篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 10篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1974年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有7084条查询结果,搜索用时 15 毫秒
81.
82.
83.
Indicators for Surgical Resection and Intraoperative Radiation Therapy for Pelvic Recurrence of Colorectal Cancer 总被引:4,自引:0,他引:4
Hashiguchi Y Sekine T Kato S Sakamoto H Nishimura Y Kazumoto T Sakura M Tanaka Y 《Diseases of the colon and rectum》2003,46(1):31-39
PURPOSE: We retrospectively analyzed prognostic factors for surgical resection and intraoperative radiation therapy to identify indicators for this treatment strategy.
METHODS: Thirty-nine consecutive patients with locally recurrent colorectal cancer who underwent surgical resection with intraoperative radiation therapy from January 1, 1987, to June 30, 1999, were analyzed. The mean electron energy was 10.5 MeV and the mean intraoperative radiation dose was 22.6 Gy. Kaplan-Meier survival estimates were obtained for the 37 patients who recovered postoperatively. Prognostic factors were analyzed univariately by log-rank test and multivariately by Coxs proportional hazards model.
RESULTS: Three-year cumulative survival was 44 percent (standard error = 11) for 26 patients free of unresectable distant metastasis who underwent surgical resection and intraoperative radiation therapy for pelvic recurrence of colorectal cancer, but none of the 11 patients with unresectable distant metastasis survived 3 years. Preoperative prognostic factors which were significant on univariate and multivariate analysis were unresectable distant metastasis (P = 0.001) and elevated preoperative serum CA 19–9 (P = 0.02). Patients with synchronous resection of local recurrence and distant metastasis had a significant survival advantage over those without resection of metastases (P = 0.02). Univariate analysis in a subgroup of 26 patients without unresectable distant metastasis revealed pain (P = 0.0003) to be a useful preoperative prognostic indicator, whereas tumor fixation (P = 0.01) and amount of residual tumor after surgical resection (P = 0.01) were significant intraoperative and postoperative factors, respectively. Fluorouracil-based postoperative systemic chemotherapy produced a significant survival benefit (P = 0.04).
CONCLUSIONS: Patients with unresectable distant metastasis are not suitable candidates for surgical resection and intraoperative radiation therapy, whereas those with resectable metastasis are potential candidates. Intraoperative radiation therapy may be less useful for patients with pain, elevated preoperative CA19–9, fixed tumors, or gross residual tumor after surgical resection. Multimodal treatment strategies combining preoperative and/or postoperative external beam radiation therapy and intraoperative radiation therapy with fluorouracil-based systemic chemotherapy are recommended for patients with these indicators. 相似文献
84.
Akihiro Hirashiki Hideo Izawa Fuji Somura Koji Obata Tomoko Kato Takao Nishizawa Akira Yamada Hiroyuki Asano Satoru Ohshima Akiko Noda Shigeo Iino Kohzo Nagata Kenji Okumura Toyoaki Murohara Mitsuhiro Yokota 《Journal of the American College of Cardiology》2006,47(7):1382-1389
OBJECTIVES: The relation between the occurrence of pacing-induced mechanical alternans and prognosis in patients with mild-to-moderate idiopathic dilated cardiomyopathy (IDCM) in sinus rhythm was investigated prospectively. The myocardial expression of genes for Ca2+-handling proteins in such patients was also examined. BACKGROUND: Mechanical alternans occurs in some patients with severe heart failure, but the relation between the occurrence of mechanical alternans and prognosis in patients with IDCM has remained unknown. METHODS: Left ventricular (LV) pressure was measured during atrial pacing, and LV endomyocardial biopsy specimens were collected in 36 IDCM patients and 8 controls. Idiopathic dilated cardiomyopathy patients were divided into two groups consisting of 22 individuals who did not develop mechanical alternans at heart rates up to 140 beats/min (group A) and of 14 individuals who did (group B). The patients were followed up for a mean of 3.7 years. RESULTS: There was no significant difference in LV ejection fraction or the plasma concentration of brain natriuretic peptide between groups A and B. The myocardial abundance of ryanodine receptor 2 messenger ribonucleic acid (mRNA) was significantly lower in groups A and B than in controls, whereas that of sarcoplasmic reticulum Ca2+-ATPase mRNA was significantly lower in group B than in group A or controls. Stepwise multivariate analysis identified pacing-induced mechanical alternans as the strongest predictor of cardiac events. Event-free survival in group A was significantly greater than that in group B. CONCLUSIONS: The occurrence of pacing-induced mechanical alternans is a potentially useful indicator of poor prognosis in patients with mild-to-moderate IDCM in sinus rhythm. 相似文献
85.
Shingen Nakamura Momoyo Azuma Tomoko Maruhashi Kimiko Sogabe Ryohei Sumitani Munenori Uemura Masami Iwasa Shiro Fujii Hirokazu Miki Kumiko Kagawa Takashi Hiraga Noriyasu Kondo Hiromi Fujita Fumihiko Mahara Masahiro Abe 《Journal of infection and chemotherapy》2018,24(5):389-392
Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne infectious disease caused by the SFTS virus (SFTSV). Clinical symptoms of SFTS often involve encephalopathy and other central neurological symptoms, particularly in seriously ill patients; however, pathogenesis of encephalopathy by SFTSV is largely unknown. Herein, we present case reports of three patients with SFTS, complicated by encephalopathy, admitted to Tokushima University hospital: one patient was a 63-year-old man, while the other two were 83- and 86-year-old women. All of them developed disturbance of consciousness around the 7th day post onset of fever. After methylprednisolone pulse therapy of 500 mg/day, all of them recovered without any neurological sequelae. SFTSV genome was not detected in the cerebrospinal fluid of 2 out of the 3 patients that were available for examination. In these patients, disturbance of consciousness seemed to be an indirect effect of the cytokine storm triggered by SFTSV infection. We propose that short-term glucocorticoid therapy might be beneficial in the treatment of encephalopathy during early phase of SFTSV infection. 相似文献
86.
87.
Background We developed and evaluated the clinical usefulness of a scoring system that subclassified type Vi pit patterns.
Methods We studied 119 colon cancer lesions (pTis, n = 26; pT1, n = 93) and 22 tubular adenoma lesions with severe atypia in which a type Vi pit pattern was visible under a stereomicroscope. Four type Vi pit pattern formation appearances (existing pits, marginal irregularities of the gland duct, narrowing of the gland duct
lumen, and unclear outline of the gland duct) were defined, and the relationship between each appearance and the invasive
depth of the cancer was evaluated.
Results When the four type Vi pit pattern appearances were considered in a logistic regression analysis, the odds of a more invasive submucosal cancer
were significantly increased by the appearance of marginal irregularities, a narrowed lumen, and an unclear outline. In the
logistic regression analysis results, when 0.63 was used as the cutoff score for prediction of a more invasive submucosal
cancer, 80 cases in the less invasive group were classified correctly (specificity, 1.0), whereas 53 (86.9%) of the 61 cases
in the more invasive group were classified correctly (sensitivity, 0.869).
Conclusions It is important first to understand the usability and limitations of objective scoring of type V pit pattern findings and
then to apply this score to the determination of cancer depth in order to accurately identify lesions suitable for endoscopic
treatment. 相似文献
88.
Myeloid/Natural Killer Cell Precursor Acute Leukemia Accompanied by Homozygous Protein C Deficiency 总被引:1,自引:0,他引:1
Shimamoto T Nakajima A Katagiri T Ito Y Ohyashiki K 《International journal of hematology》2003,78(2):149-153
A patient with myeloid/natural killer (NK) cell precursor acute leukemia who was also homozygous for protein C deficiency was treated and showed a complete remission while he simultaneously received low molecular weight heparin. He presented with fever spikes, lymphadenopathy, and a bulky tumor of the anterior mediastinum. A bone marrow aspirate showed the infiltration of immature lymphoblastoid cells. The patient's diagnosis was determined to be myeloid/NK cell precursor acute leukemia by morphologic and immunophenotypic analysis (CD7(+)CD33(+)CD34(+)CD56(+)). The patient developed a thrombosis in his jugular vein on cannulation of the internal jugular vein. An examination of the serum levels and the activities of proteins C and S demonstrated a slight decrease in the protein C level but an undetectable protein C activity. The patient received the diagnosis of homozygous protein C deficiency, because both parents were found to have heterozygous protein C activity. Treatment of the patient's leukemia included induction chemotherapy (Ara-C and idarubicin) with concomitant administration of low molecular weight heparin for his homozygous protein C deficiency. He achieved a complete remission without expressing any thrombosis during the course of chemotherapy. To our knowledge, this is the first case ever described in which acute myeloid leukemia was complicated with homozygous protein C deficiency. 相似文献
89.
90.
Mayumi Yamamoto Yukihiko Konishi Ikuko Kato Kosuke Koyano Shinji Nakamura Tomoko Nishida Takashi Kusaka 《Brain & development》2021,43(2):186-191
BackgroundProgress in neonatal medicine has dramatically improved the survival rate of preterm births, but the evidence suggests that these low-birth weight infants (LBWIs) go on to develop pervasive development disorders and attention deficit hyperactivity disorder (ADHD) at greater rates than the general population. Children with neurodevelopmental disorders are known to suffer from deficits in visual cognition, such as in face perception and attentional functions, the characteristics of which already manifest in early infancy.PurposeThis study aimed to investigate visual cognition in LBWIs during infancy.Subjects20 LBWIs and 20 normal-birth-weight infants (NBWIs: control) of age 9–10 months (corrected age was used for LBWIs).MethodChildren were held seated in front of an eye tracking system by a parent, and presented with facial photos as visual stimuli. During the familiarization phase, the child was presented with two images of the same human face (familiarization stimulus) on the left and right side of a display screen (5 × 10 s trials). Next, during the test phase, the child was presented with the same image on one side of the screen, and a photo of a different person’s face (novel stimulus) on the other (2 × 5 s trials). Gaze behavior was assessed in terms of the total time spent looking at either facial stimulus, and specifically at the eyes of the stimuli, as well as the number of attentional shifts between stimuli, and novelty preference.Results/DiscussionLBWIs spent significant less time looking at facial stimuli overall, and less time at the eye region, than NBWIs. These findings seem to evidence developmental differences in functions related to visual cognition. 相似文献