全文获取类型
收费全文 | 33435篇 |
免费 | 2094篇 |
国内免费 | 265篇 |
专业分类
耳鼻咽喉 | 445篇 |
儿科学 | 602篇 |
妇产科学 | 496篇 |
基础医学 | 4158篇 |
口腔科学 | 1553篇 |
临床医学 | 2744篇 |
内科学 | 9012篇 |
皮肤病学 | 394篇 |
神经病学 | 3366篇 |
特种医学 | 1312篇 |
外科学 | 5323篇 |
综合类 | 93篇 |
一般理论 | 6篇 |
预防医学 | 1407篇 |
眼科学 | 546篇 |
药学 | 1736篇 |
中国医学 | 73篇 |
肿瘤学 | 2528篇 |
出版年
2024年 | 32篇 |
2023年 | 360篇 |
2022年 | 671篇 |
2021年 | 1259篇 |
2020年 | 754篇 |
2019年 | 1023篇 |
2018年 | 1213篇 |
2017年 | 959篇 |
2016年 | 1072篇 |
2015年 | 1134篇 |
2014年 | 1466篇 |
2013年 | 1789篇 |
2012年 | 2790篇 |
2011年 | 2689篇 |
2010年 | 1509篇 |
2009年 | 1366篇 |
2008年 | 2153篇 |
2007年 | 2274篇 |
2006年 | 2038篇 |
2005年 | 1852篇 |
2004年 | 1651篇 |
2003年 | 1516篇 |
2002年 | 1313篇 |
2001年 | 282篇 |
2000年 | 245篇 |
1999年 | 251篇 |
1998年 | 246篇 |
1997年 | 205篇 |
1996年 | 156篇 |
1995年 | 145篇 |
1994年 | 132篇 |
1993年 | 114篇 |
1992年 | 125篇 |
1991年 | 100篇 |
1990年 | 87篇 |
1989年 | 61篇 |
1988年 | 92篇 |
1987年 | 63篇 |
1986年 | 49篇 |
1985年 | 65篇 |
1984年 | 55篇 |
1983年 | 45篇 |
1982年 | 47篇 |
1981年 | 29篇 |
1980年 | 24篇 |
1979年 | 42篇 |
1978年 | 31篇 |
1977年 | 22篇 |
1973年 | 31篇 |
1972年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
Prof. Alessandro Bianco MD Marco Cagossi MD Daniela Scrimieri MD Virgilio Greco MD 《Digestive diseases and sciences》1986,31(1):40-48
The authors studied 22 patients with severe dysphagia, and follow-up studies showed the appearance of some esophageal peristalsis for the first time in three of these patients after Heller myotomy. Comparison of pre- and postoperative clinical, radiological, and manometric data of these three subjects and the data of the other 19 patients showed no statistically significant differences between the two groups of patients either before or after cardiomyotomy except for the unusual appearance of esophageal peristalsis after surgery. According to these results it is not possible to predict which patients will develop peristalsis after cardiomyotomy. The different motor pattern observed after surgery might suggest the existence of a different pathogenesis underlying the esophageal motor disorders in these two groups of patients. 相似文献
72.
How do genes exert their role? Period 3 gene variants and possible influences on mood disorder phenotypes 总被引:1,自引:0,他引:1
Paola Artioli Cristina Lorenzi Adele Pirovano Alessandro Serretti Francesco Benedetti Marco Catalano Enrico Smeraldi 《European neuropsychopharmacology》2007,17(9):587-594
The action of multiple liability genes is responsible for complex phenotypes at the same time, a single gene, could control several phenotypic features. This is the case of human period 3 gene (hper3), mainly involved in the setting of the biologic clock. Some variants of this gene, besides being associated with the Delayed Sleep Phase Syndrome, showed a key role in determining evening preference rather than morning one. According to this rationale, we hypothesized that this gene could influence circadian mood fluctuations, in mood disorders. Our study demonstrated that rare genetic variants of hper3 are significantly associated to a number of mood disorders features, such as age of onset, response to SSRIs treatment, circadian mood oscillations and characteristics of temperament. These preliminary results could shed further light on the involvement of circadian genes in various aspects of physiological and psychopathological mechanisms of the brain. 相似文献
73.
74.
Andrea Sagripanti Adamasco Cupisti Ugo Baicchi Marco Ferdeghini Giuliano Barsotti 《International Journal of Clinical & Laboratory Research》1994,24(2):113-116
Summary Intraglomerular fibrin deposition has been implicated as an important pathogenetic mechanism in patients with glomerular diseases
and the nephrotic syndrome. To investigate fibrin formation and degradation in nephrosis, we measured fibrinopeptide A by
radio-immunoassay and D-dimer by enzyme-linked immunosorbent assay in the plasma of 30 consecutive adult patients with the
nephrotic syndrome; in 10 the serum creatinine was more than 2 mg/dl. Both fibrinopeptide A and D-dimer were abnormally elevated
in the majority of nephrotics (P<0.001 vs. healthy controls), providing evidence of increased fibrin generation and lysis “in vivo.” A positive correlation
was found between fibrinopeptide A and D-dimer (correlation coefficient 0.64,P<0.001), suggesting a close relationship between fibrin formation and degradation. Calcium heparin, administered to 12 nephrotics,
caused a marked decrease in plasma fibrinopeptide A, due to a reduction of in vivo thrombin activity. As enhanced thrombin
activity can favor fibrin deposition within the renal parenchyma, as well as vascular complications, it is reasonable to assume
that an antithrombotic treatment aimed at controlling thrombin generation may ameliorate the natural history of nephrosis. 相似文献
75.
Osteosarcoma has been divided into numerous varieties based on clinical, radiographic, and histologic characteristics. Small cell osteosarcoma is a distinct subtype with a histologic appearance in which the bulk of the lesion is composed of round malignant cells with minimal areas of spindle cells. Osteoid production is always present. The lesion may mimic Ewing's tumor and other lesions in which round cells are seen. We report the clinical, radiologic, and pathologic features of this tumor, as well as the clinical outcome and response to therapy. 相似文献
76.
77.
Francesca Lodato Maria Rosa Tamé Marco Montagnani Vittorio Sambri Giovanna Liguori Francesco Azzaroli Paolo Costigliola Gianluca Grazi Enrico Roda Giuseppe Mazzella 《Liver transplantation》2006,12(11):1711-1714
The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation. 相似文献
78.
In the present study we evaluated the effects of climacteric modifications on body weight and fat distribution. From women attending a menopause clinic we selected 2175 untreated, normal healthy women who were divided into three groups: premenopausal (n = 540), perimenopausal (n = 750) and postmenopausal (n = 885), and compared them with 354 postmenopausal women receiving different forms of hormone replacement therapy (HRT). The total body fat tissue mass and distribution were analyzed using dual-energy X-ray absorptiometry. Body weight and body mass index (BMI) were significantly higher in perimenopausal and postmenopausal than in premenopausal women. Mean total body fat and fat as a percentage of soft tissue were significantly (p < 0.05) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. Fat tissue and regional fat tissue as a percentage of total fat tissue were higher in the trunk (p < 0.0001) and arms (p < 0.0001) in perimenopausal and postmenopausal than in premenopausal women. In postmenopausal women, leg fat tissue was significantly (p < 0.05) lower than in premenopausal and perimenopausal groups. Total body and leg lean tissue were significantly lower (p < 0.05) in postmenopausal than in premenopausal and perimenopausal women. In age-matched women with similar BMI, total body fat as a percentage of soft tissue was significantly (p < 0.001) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. As for body fat distribution, fat as a percentage of total fat tissue was significantly higher in the trunk (p < 0.0001) region in perimenopausal and postmenopausal women compared with the premenopausal group. In the legs, fat as a percentage of total fat tissue was significantly higher (p < 0.05) in the premenopausal than in the postmenopausal group. In the arms a slight but not significant (p < 0.18) difference was shown in fat distribution between the three untreated groups. In age-matched HRT-treated postmenopausal women, the fat tissue was similar to that in the premenopausal group. The present results confirm that endocrine changes during the menopausal transition, rather than the aging process, are related to changes in body weight and fat distribution. Perimenopausal and postmenopausal women show a shift to a central, android fat distribution that can be counteracted by HRT. 相似文献
79.
Ana María Fortuna Marco Balleza Núria Calaf Mercedes González Teresa Feixas Pere Casan 《Archivos de bronconeumologia》2009,45(3):143-147
Nitric oxide (NO) production has been described using a 2-compartment model for the synthesis and movement of NO in both the alveoli and the airways. The alveolar concentration of NO (CaNO), an indirect marker of the inflammatory state of the distal portions of the lung, can be deduced through exhalation at multiple flow rates. Our objective was to determine reference values for CaNO. The fraction of exhaled NO (FeNO) was measured in 33 healthy individuals at a rate of 50 mL/s; the subjects then exhaled at 10, 30, 100, and 200 mL/s to calculate CaNO. A chemiluminescence analyzer (NIOX Aerocrine) was used to perform the measurements. The mean (SD) FeNO was 15 (6) ppb. The mean CaNO was 3.04 (1.30) ppb. These values of CaNO measured in healthy individuals will allow us to analyze alveolar inflammatory behavior in respiratory and systemic processes. 相似文献
80.