全文获取类型
收费全文 | 14155篇 |
免费 | 679篇 |
国内免费 | 118篇 |
专业分类
耳鼻咽喉 | 95篇 |
儿科学 | 276篇 |
妇产科学 | 408篇 |
基础医学 | 1743篇 |
口腔科学 | 354篇 |
临床医学 | 977篇 |
内科学 | 4025篇 |
皮肤病学 | 242篇 |
神经病学 | 1348篇 |
特种医学 | 583篇 |
外科学 | 2096篇 |
综合类 | 34篇 |
一般理论 | 1篇 |
预防医学 | 506篇 |
眼科学 | 160篇 |
药学 | 714篇 |
中国医学 | 23篇 |
肿瘤学 | 1367篇 |
出版年
2024年 | 12篇 |
2023年 | 89篇 |
2022年 | 200篇 |
2021年 | 410篇 |
2020年 | 209篇 |
2019年 | 298篇 |
2018年 | 389篇 |
2017年 | 290篇 |
2016年 | 326篇 |
2015年 | 367篇 |
2014年 | 555篇 |
2013年 | 707篇 |
2012年 | 982篇 |
2011年 | 1000篇 |
2010年 | 645篇 |
2009年 | 581篇 |
2008年 | 1000篇 |
2007年 | 1006篇 |
2006年 | 912篇 |
2005年 | 960篇 |
2004年 | 861篇 |
2003年 | 787篇 |
2002年 | 707篇 |
2001年 | 104篇 |
2000年 | 97篇 |
1999年 | 116篇 |
1998年 | 148篇 |
1997年 | 116篇 |
1996年 | 135篇 |
1995年 | 87篇 |
1994年 | 100篇 |
1993年 | 80篇 |
1992年 | 75篇 |
1991年 | 61篇 |
1990年 | 54篇 |
1989年 | 45篇 |
1988年 | 32篇 |
1987年 | 22篇 |
1986年 | 37篇 |
1985年 | 32篇 |
1984年 | 30篇 |
1983年 | 23篇 |
1982年 | 34篇 |
1981年 | 34篇 |
1980年 | 32篇 |
1979年 | 21篇 |
1976年 | 11篇 |
1975年 | 9篇 |
1974年 | 10篇 |
1964年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
1.
The second part of this review addresses the treatment and prognosis of the vasculitides Wegener's granulomatosis, microscopic
polyangiitis, Churg–Strauss syndrome and polyarteritis nodosa. Treatment regimens consist of an initial remission phase with
aggressive immunosuppression, followed by a more prolonged maintenance phase using less toxic agents and doses. This review
focuses on the initial treatment of fulminant vasculitis, the mainstay of which remains immunosuppression with steroids and
cyclophosphamide. For Wegener's granulomatosis and microscopic polyangiitis plasma exchange can be considered for first-line
therapy in patients with acute renal failure and/or pulmonary haemorrhage. Refractory disease is rare and is usually due to
inadequate treatment. The vasculitides provide a particular challenge for the critical care team. Particular aspects of major
organ support related to these conditions are discussed. Effective treatment has revolutionized the prognosis of these conditions.
However, mortality is still approximately 50% for those requiring admission to intensive care unit. Furthermore, there is
a high morbidity associated with both the diseases themselves and the treatment. 相似文献
2.
Giuseppina Di Stefano Luigi Fiume Michele Baglioni Corrado Busi Pasquale Chieco Felix Kratz Alessandro Mattioli 《European journal of pharmaceutical sciences》2007,30(2):136-142
Several attempts have been made to enhance doxorubicin (DOXO) concentrations in tumour cells by drug conjugation with human albumin (HSA). HSA-DOXO has the drawback of causing DOXO accumulation in spleen and bone marrow, with a consequent leucopoenia not produced when lactose molecules are coupled to the carrier protein. In the present experiments we demonstrated that the effect of HSA lactosamination is not a consequence of a more rapid disappearance from the bloodstream of the lactosaminated conjugate (L-HSA-DOXO), which is rapidly internalized by the liver through the asialoglycoprotein receptor, but is due to a hindered uptake by spleen and bone marrow cells caused by the coupled lactose molecules. Experiments in vitro showed that HSA-DOXO produced an inhibition of murine macrophage proliferation not caused by L-HSA-DOXO. This result can be explained by higher amounts of the former conjugate entering in these cells and suggests macrophages as the cell type responsible for the spleen and bone marrow internalization of HSA-DOXO hindered by lactose coupling. Importantly, lactosamination of HSA did not reduce the marked uptake of HSA-DOXO by chemically induced rat hepatocellular carcinoma. L-HSA-DOXO, by avoiding DOXO accumulation in bone marrow is an attractive candidate for clinical trials against tumors which were found to actively internalize this conjugate in laboratory animals, such as hepatocellular carcinoma. 相似文献
3.
Luigi Paolo Badano Maria C Albanese Paola De Biaggio Patrizia Rozbowsky Daniela Miani Claudio Fresco Paolo M Fioretti 《Journal of the American Society of Echocardiography》2004,17(3):253-261
Prevalence of isolated left ventricular (LV) diastolic dysfunction has been reported to be as high as one-third of all heart failure (HF) cases, with an increasing prevalence in the elderly population. However, there is a paucity of prospective data about the prevalence and prognosis of isolated LV diastolic dysfunction in an unselected population of patients hospitalized with HF. Therefore, we prospectively evaluated 179 consecutive patients discharged from our hospital with HF to assess the prevalence of systolic versus diastolic LV dysfunction among patients hospitalized with HF and to compare their demographics, clinical features, self-perceived quality of life (QOL), and 6-month readmission rate and mortality. Among them, 133 (59% men, median age 74 years) showed in sinus rhythm and had no significant primary valvular disease. LV diastolic dysfunction was diagnosed on the basis of the European Study Group on Diastolic HF echocardiographic criteria. QOL was assessed at hospital discharge and 6-month follow-up visit using the Minnesota Living with HF questionnaire. Survival of patients with HF was compared with that of age- and sex-matched general population. In all, 29 patients (22%) had isolated LV diastolic dysfunction and 102 (78%) had prevalent LV systolic dysfunction (ie, LV ejection fraction = 45%). There was no difference in age, sex, or New York Heart Association functional class between patients with LV diastolic or systolic dysfunction. QOL scores were similar between the 2 patient groups with HF both at discharge (39.4 and 34) and at 6-month visit (10.4 and 10.4). Both 6-month readmission rate (48% and 48%) and median inhospital length-of-stay during readmissions (10 days and 10 days) were similar between the 2 patient groups with HF. Finally, 6-month survival, adjusted for age and sex, was similar between patients with LV diastolic or systolic dysfunction (hazard ratio 0.68; 95% confidence interval 0.20-2.35). Using standardized echocardiographic criteria, isolated LV diastolic dysfunction among unselected patients hospitalized with HF was less than previously reported. Patients with HF and isolated diastolic dysfunction showed similar clinical symptoms, self-perceived QOL, readmission rate, and 6-month mortality to patients with prevalent LV systolic dysfunction. 相似文献
4.
Salvatore Serra Giuliana Brunetti Giovanni Vacca Carla Lobina Mauro A M Carai Gian Luigi Gessa Giancarlo Colombo 《Alcohol》2003,29(2):101-108
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption. 相似文献
5.
Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been
reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders.
Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central
nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several
regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the
hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF,
but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading
to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human
schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system.
Received: 18 January 1996 / Revised, accepted: 16 April 1996 相似文献
6.
Giuseppe Montalto Leonardo Ficano Antonio Carroccio Francesco D''arpa Luigi Greco Maurizio Soresi Pasquale Salvo 《Journal of Hepato-Biliary-Pancreatic Surgery》1994,1(5):573-577
The clinical and biochemical presentation of carcinoma of the pancreas (PC) and of the papilla of Vater (CPV) are very similar, and, consequently, detailed investigations are required to correctly distinguish between them. The aim of the present study was to select the clinical and biochemical variables that would most efficiently discriminate the precise site of tumor origin. The study group consisted of 72 patients with PC and 22 patients with CPV consecutively hospitalized in our department. The following clinical parameters were considered: age, asthenia, anorexia, vomiting, weight loss, pain, fever, pruritis, and constipation; the biochemical parameters considered were total, direct, and indirect bilirubin, glucose, alkaline phosphatase, gamma glutamy transferase, transaminase, total protein, amylase, and occult blood in stools. The results indicated that in the initial phase of PC the most frequent clinical parameters were weight loss (P<0.0001), anorexia (P<0.02), constipation (P<0.001), and pruritus (P<0.01). In contrast, in CPV, fever (P<0.003) was most frequent in the same phase. There was a statistically significant difference in occult blood in stools (P<0.0001), total (P<0.03) and direct bilirubin (P<0.02), alkaline phosphatase (P<0.05), and transaminase (P<0.002) values in the two groups. On discriminant analysis, weight loss, constipation, pruritus, nausea, anorexia, and fever were the variables which best discriminated between the two types of tumors. In fact, the presence of weight loss, anorexia, asthenia, constipation, and pruritus correctly classified 87.5% of the patients with PC, while the presence of fever and nausea correctly classified 72.7% of the patients with CPV. 相似文献
7.
8.
Mario Lapecorella Assunta Orecchioni Luigi Dell'Orso Guglielmo Mariani 《Blood coagulation & fibrinolysis》2007,18(5):513-517
The intake of steroid hormone contraceptives is a strong and independent risk factor for venous thromboembolism. Several studies have assessed an increased risk of venous thromboembolism in women using oral contraceptives who are carriers of the G20210A mutation in the prothrombin gene. Most trials evaluating the thrombotic risk of oral contraceptives are based on combined oral preparations, but only a few focus on progestogen-only oral preparations. Results from such studies are conflicting and globally assess the thrombotic risk, ranging from modest to slightly increased. Furthermore, little is known about the relationship between the C677T mutation in the methylenetetrahydrofolate reductase gene and the progestogen-based preparations. Herewith we report the case of a 49-year-old woman with a complex genetic thrombosis risk factor who had taken oral progesterone for 15 months without any complication, but then experienced severe left upper extremity deep vein thrombosis 2 months after the drug suspension. 相似文献
9.
10.