全文获取类型
收费全文 | 11106篇 |
免费 | 722篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 63篇 |
儿科学 | 254篇 |
妇产科学 | 280篇 |
基础医学 | 1548篇 |
口腔科学 | 396篇 |
临床医学 | 1019篇 |
内科学 | 2290篇 |
皮肤病学 | 226篇 |
神经病学 | 1341篇 |
特种医学 | 327篇 |
外科学 | 1300篇 |
综合类 | 24篇 |
现状与发展 | 1篇 |
一般理论 | 8篇 |
预防医学 | 983篇 |
眼科学 | 121篇 |
药学 | 695篇 |
中国医学 | 49篇 |
肿瘤学 | 968篇 |
出版年
2024年 | 17篇 |
2023年 | 122篇 |
2022年 | 250篇 |
2021年 | 431篇 |
2020年 | 263篇 |
2019年 | 403篇 |
2018年 | 437篇 |
2017年 | 352篇 |
2016年 | 409篇 |
2015年 | 378篇 |
2014年 | 468篇 |
2013年 | 620篇 |
2012年 | 880篇 |
2011年 | 861篇 |
2010年 | 460篇 |
2009年 | 436篇 |
2008年 | 683篇 |
2007年 | 653篇 |
2006年 | 647篇 |
2005年 | 581篇 |
2004年 | 548篇 |
2003年 | 492篇 |
2002年 | 398篇 |
2001年 | 124篇 |
2000年 | 99篇 |
1999年 | 124篇 |
1998年 | 61篇 |
1997年 | 75篇 |
1996年 | 40篇 |
1995年 | 38篇 |
1994年 | 31篇 |
1993年 | 25篇 |
1992年 | 54篇 |
1991年 | 67篇 |
1990年 | 38篇 |
1989年 | 45篇 |
1988年 | 33篇 |
1987年 | 35篇 |
1986年 | 29篇 |
1985年 | 25篇 |
1984年 | 26篇 |
1983年 | 9篇 |
1982年 | 17篇 |
1981年 | 10篇 |
1980年 | 9篇 |
1979年 | 13篇 |
1977年 | 11篇 |
1974年 | 12篇 |
1973年 | 8篇 |
1971年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Babiloni C Vecchio F Rossi S De Capua A Bartalini S Ulivelli M Rossini PM 《Cerebral cortex (New York, N.Y. : 1991)》2007,17(6):1486-1492
In this paper, we used repetitive transcranial magnetic stimulation (rTMS) in 18 normal subjects to investigate whether the ventral posterior parietal cortex (PPC) plays a causal role on visuospatial attention and primary consciousness and whether these 2 functions are linearly correlated with each other. Two distinct experimental conditions involved a similar visual stimuli recognition paradigm. In "Consciousness" experiment, number of consciously perceived visual stimuli was lower by about 10% after rTMS (300 ms, 20 Hz, motor threshold intensity) on left or right PPC than after sham (pseudo) rTMS. In "Attentional" Posner's experiment, these stimuli were always consciously perceived. Compared with sham condition, parietal rTMS slowed of about 25 ms reaction time to go stimuli, thus disclosing effects on endogenous covert spatial attention. No linear correlation was observed between the rTMS-induced impairment on attention and conscious perception. Results suggest that PPC plays a slight but significant causal role in both visuospatial attention and primary consciousness. Furthermore, these high-level cognitive functions, as modulated by parietal rTMS, do not seem to share either linear or simple relationships. 相似文献
82.
The present study investigated the control of movements in two patients with severe somatosensory deafferentation by systematically manipulating the visual information about the produced movements. In a synchronization task requiring the production of finger taps in synchrony with a regular auditory signal, participants controlled their movements under full vision or when the sight of the effector was partially or completely occluded. Results demonstrated large effects of visual feedback on the synchronization performance in the deafferented patients. Although the patients' performance differed substantially from that of unimpaired controls under partial or no feedback, their performance was comparable under full vision, the latter suggesting a compensation of the somatosensory loss by visual monitoring. 相似文献
83.
Senhorini MC Amaro Júnior E de Mello Ayres A de Simone A Busatto GF 《Journal of clinical and experimental neuropsychology》2006,28(7):1191-1200
Phonological verbal fluency studies in English most commonly employ the letters F-A-S as stimuli. We assessed the production of words with these and 14 other letters in Portuguese-speaking healthy subjects (n = 74). The letters F-A-S were ranked among the easiest to produce words in one minute, which is consistent with the findings of studies with English-speaking subjects. There were differences in the overall ranking of letters depending on whether the total word number or the latency between words were considered. Our findings provide a databank of phonological verbal fluency performance using different stimuli in Portuguese, and demonstrate that the ranking of the letters F-A-S is comparable between the English and Portuguese languages in terms of the level of difficulty to produce words, when the task is used in its traditional format. 相似文献
84.
Krzossok S Braun C Weiss E Hoeger S Schnuelle P Benck U Birck R Krämer BK Göttmann U 《Kidney & blood pressure research》2011,34(2):125-134
Background: N-acetylcysteine (NAC) has been proposed to prevent radiocontrast nephropathy in high-risk patients. Methods: The effect of single-dose and prolonged administration of NAC before application of either the ionic, high-osmolar radiocontrast agent diatrizoate sodium (DTZ) or the nonionic, low-osmolar radiocontrast agent iohexol (IOH) in a rat model combining uninephrectomy, salt depletion, and administration of indomethacin was explored. Arterial blood pressure and total, cortical, and medullary blood flow were continuously recorded in anesthetized Sprague-Dawley rats. Results: NAC had no effect on renal hemodynamics in control rats. Both DTZ and IOH induced biphasic changes in renal blood flow and cortical renal blood flux and persistently reduced medullary blood flux. Neither single-dose nor prolonged administration of NAC prevented the hemodynamic changes following administration of DTZ or IOH, respectively. Acute prophylactic administration of NAC prevented increased urinary ET excretion after injection of IOH and, to a smaller degree, of DTZ. Both an ionic, high-osmolar (DTZ) and a nonionic, low-osmolar (IOH) radiocontrast agent induce marked changes in renal hemodynamics in salt-depleted rats treated with indomethacin. Conclusions: Renal perfusion is not affected by NAC application in a model of experimental contrast nephropathy in rats. Other effects of NAC might thus account for the presumed renoprotective properties. 相似文献
85.
De Nunzio C Carbone A Albisinni S Alpi G Cantiani A Liberti M Tubaro A Iori F 《World journal of urology》2011,29(4):517-521
Purpose
To study the benefits of a single, early, intravesical instillation of mitomycin C(MMC) after transurethral bladder resection (TURB) in patients with low-risk non-muscle-invasive bladder cancer (NMIBC). 相似文献86.
Hussein H Karnib Simone Sanna-Cherchi Pierre A Zalloua Walid Medawar Vivette D D'Agati Richard P Lifton Kamal Badr Ali G Gharavi 《Nephrology, dialysis, transplantation》2007,22(3):772-777
BACKGROUND: Familial aggregation of IgA nephropathy (IgAN) suggests that genetic factors contribute to the development of this trait. Because clinical manifestations in IgAN families are often limited to episodic haematuria, large kindreds tractable to linkage analysis have been difficult to identify. METHODS: We identified a large Lebanese-Druze kindred ascertained via an index case with biopsy-documented IgAN. We performed systematic screening of 38 family members and tested linkage to reported IgAN loci. RESULTS: Screening of this family identified 16 affected individuals, including 2 individuals with biopsy-documented IgAN and 14 with chronic renal failure or abnormal urinalyses on at least three separate occasions. This kindred spanned five generations and contained five consanguineous unions. Multigenerational inheritance suggested that autosomal dominant inheritance was most likely. Phenotypic manifestations among affected individuals varied from isolated haematuria to advanced renal failure necessitating transplantation; one instance of IgAN recurrence after transplantation was also documented. Older age was associated with greater severity of disease and higher incidence of renal failure. Parametric and non-parametric analyses with 33 microsatellite markers did not reveal any evidence of linkage to reported IgAN loci on chromosomes 6q22-23, 2q36 and 4q22-31. CONCLUSIONS: We describe one of the largest multigenerational IgAN kindreds reported to date. The high incidence of renal failure among older generations suggests a significant risk of progression to renal failure. We found no evidence of linkage to known loci, suggesting that familial IgAN encompasses multiple subtypes that will require distinction based on genetic or biomarker data. 相似文献
87.
88.
Sergio Sabbatani Fausto Catena Flavia Neri Carlo Vallicelli Luca Ansaloni Massimo Sartelli Federico Coccolini Salomone Di Saverio Rodolfo Catena Daniel Lazzareschi Antonio Tarasconi Hariscine K. Abongwa Belinda De Simone Antonio Pinna 《The Journal of surgical research》2014
Background
The first reliable statistic data about perioperatory mortality were published in 1841 by the French Joseph-Francois Malgaigne (1806–1863): he referred to a mean mortality of 60% for amputations and this bad result was to be attributed mainly to hospital acquired diseases. The idea of “hospital acquired disease” although vague, included five infective nosologic entities, which at that time were diagnosed more frequently: erysipelas, tetan, pyemia, septicemia, and gangrene. Nonetheless, the suppuration with pus production was considered from most of the surgeons and doctors of that time as a necessary and unavoidable step in the process of wound healing. During the end of the eighteenth century, hospitals of the main European cities were transforming into aggregations of several wards, where the high concentration of patients created poor sanitary conditions and a consistent increase of perioperatory mortality. In 1865, Lister applied his first antiseptic dressing on the surface of an exposed fracture. These experimental attempts lead to an effective reduction of wound infections respect to the dressing with strings used previously.Discussion
Lister's innovations in the field of wound treatment were based on two brand new concepts: germs causing rot were ubiquitarious and the wound infection was not a normal step in the process of wound healing. The concept of antisepsis was hardly accepted in the European surgical world: “Of all countries, Italy is the most indifferent and uninterested in experimenting this method, which has been so favorably judged from the greatest surgical societies in Germany”. This quotation from the young surgeon Giuseppe Ruggi (1844–1925) from Bologna comes from his article where he presented his first experiences on aseptic medications started the previous year in the Surgical Department of Maggiore Hospital in Bologna. In his report, Ruggi described the adopted technique and suggested that the medication should be extended to all the surgical patients of the hospital:“… this is needed to totally remove from the hospital all those elements of infection which grow in the wounds dressed with the old method”. The experimentation of this new dressing for the few treated cases was rigorous and concerned both the sterilization of surgical tools with the fenic acid (5%) and the shaving of the skin. Ruggi also observed that there was no correlation between the seriousness of the wound and its extension or way of healing: when “simple” cases that “should heal without complication” showed fever he often realized that “it was often due to a medication performed without following the rules for an accurate disinfection and dressing”. Ruggi thought that the fever was connected to “reabsorption of pyrogenic substances, which can be removed cleaning and disinfecting the wound” in cases of wounds not accurately dressed and rarely medicated. Frequent postoperative medications of the wound were able to eliminate the fever within 2 h. Ruggi's attitude toward the fine reasoning lead him to introduce the concept of immunodeficiency related to physical deterioration: “… patients treated for surgical disease may sometimes suffer from complications of medical conditions, which initially escape the most accurate investigations… The surgical operation could, in some cases, hold the balance of power”.Conclusions
The obtained results, published in 1879, appear extremely interesting. As he wrote in 1898, for the presentation of his case record of more than 1000 laparotomies, he had started “… operating as a young surgeon without any tutor, helped only by his mind and what he could deduce from publications existing at the moment …”. 相似文献89.
Paolo Gritti Luigi Andrea Lanterna Lidia Rotasperti Matteo Filippini Simone Cazzaniga Carlo Brembilla Tatyana Sarnecki Ferdinando Luca Lorini 《Journal of anesthesia》2014,28(5):687-695
Purpose
Knowledge of the cumulative balance of sodium (CBS) is important for the diagnosis of salt disorders and water homeostasis and has the potential to predict hypovolemic status in acute neurological patients. However, an extensive application of the use of CBS is still lacking in the intensive care setting, where salt and water homeostasis represents a priority.Methods
Records of consecutive series of acute neurological patients admitted to a neurointensive care unit over a 6-month period were retrospectively reviewed. CBS was calculated at the admission to the Emergency Department. Discrimination between cerebral salt-wasting syndrome (CSWS) and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) was performed on the basis of the classical criteria. Additionally, we used the findings of a negative CBS exceeding 2 mEq/kg for the diagnosis of CSWS. Two independent clinicians who were blinded to the CBS results performed diagnosis of the causes of hyponatremia and estimated the daily volemic status of the patients on the basis of clinical parameters. Logistic regression analysis was used to determine the independent prognostic factors of hypovolemia.Results
Thirty-five patients were studied for a total of 418 days. Four patients (11.4 %) fitted the criteria of CSWS and three patients (8.5 %) had SIADH. The unavailability of the CBS led to a wrong diagnosis in three of the eight hyponatremic patients (37.5 %). The risk of developing hypovolemia in patients with negative CBS was 7.1 times higher (CI 3.86–13.06; p < 0.001). Multivariate analysis revealed that negative cumulative fluid balance, negative CBS >2 mEq/kg, and CVP ≤5 cmH2O were independent prognostic factors for hypovolemia.Conclusions
CBS is likely to be a useful parameter in the diagnosis of CSWS and a surrogate parameter for estimating hypovolemia in acute neurological patients. 相似文献90.
Simone F. Nery Sara P.C. Paiva rica L. Vieira Andressa B. Barbosa Edna M. Sant'Anna Maira Casalechi Cynthia Dela Cruz Antnio L. Teixeira Fernando M. Reis 《Stress and health》2019,35(1):49-58
Infertile women often experience chronic stress, which may have a negative impact on general well‐being and may increase the burden of infertility. In this open‐label, parallel, randomized controlled trial, infertile women aged 18–50 years (median 37 years) were assigned to an 8‐week mindfulness‐based program (MBP) or no intervention. The primary outcome was stress severity measured by the Lipp's Stress Symptoms Inventory (ISSL). Data were analyzed by modified intent‐to‐treat principle, which included all cases available to follow‐up regardless of adherence to the intervention (62 participants from the MBP group and 37 from the control group). The median number of symptoms of chronic stress recorded in the past month decreased from six (interquartile range 2 to 9) before the MBP to two (interquartile range 1 to 4) after the intervention (p < 0.001, repeated measures analysis of variance with Time × Group interaction). Depressive symptoms also decreased after MBP, whereas general well‐being improved (p < 0.01 for both outcomes). Hair cortisol and serum brain‐derived neurotrophic factor (BDNF) did not change significantly between preintervention and postintervention. None of the outcomes changed significantly in the control group. MBP was effective in reducing stress and depressive symptoms while increasing general well‐being in infertile women. 相似文献