全文获取类型
收费全文 | 8088篇 |
免费 | 618篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 130篇 |
儿科学 | 252篇 |
妇产科学 | 238篇 |
基础医学 | 1167篇 |
口腔科学 | 112篇 |
临床医学 | 850篇 |
内科学 | 1765篇 |
皮肤病学 | 111篇 |
神经病学 | 748篇 |
特种医学 | 192篇 |
外科学 | 915篇 |
综合类 | 135篇 |
一般理论 | 9篇 |
预防医学 | 811篇 |
眼科学 | 66篇 |
药学 | 523篇 |
中国医学 | 12篇 |
肿瘤学 | 683篇 |
出版年
2023年 | 66篇 |
2022年 | 81篇 |
2021年 | 200篇 |
2020年 | 116篇 |
2019年 | 212篇 |
2018年 | 248篇 |
2017年 | 157篇 |
2016年 | 178篇 |
2015年 | 212篇 |
2014年 | 270篇 |
2013年 | 399篇 |
2012年 | 574篇 |
2011年 | 574篇 |
2010年 | 314篇 |
2009年 | 249篇 |
2008年 | 416篇 |
2007年 | 423篇 |
2006年 | 405篇 |
2005年 | 359篇 |
2004年 | 336篇 |
2003年 | 308篇 |
2002年 | 300篇 |
2001年 | 176篇 |
2000年 | 174篇 |
1999年 | 155篇 |
1998年 | 75篇 |
1997年 | 53篇 |
1996年 | 54篇 |
1995年 | 52篇 |
1994年 | 60篇 |
1993年 | 42篇 |
1992年 | 117篇 |
1991年 | 122篇 |
1990年 | 94篇 |
1989年 | 101篇 |
1988年 | 103篇 |
1987年 | 93篇 |
1986年 | 93篇 |
1985年 | 75篇 |
1984年 | 51篇 |
1983年 | 48篇 |
1982年 | 34篇 |
1981年 | 30篇 |
1980年 | 32篇 |
1979年 | 66篇 |
1978年 | 50篇 |
1976年 | 34篇 |
1974年 | 32篇 |
1970年 | 26篇 |
1966年 | 26篇 |
排序方式: 共有8719条查询结果,搜索用时 15 毫秒
81.
Hew WS Carey FA Kernohan NM Heppleston AD Jackson R Jarrett RF 《Journal of clinical pathology》2002,55(1):61-63
Lymphoma of the salivary gland accounts for 5% of cases of extranodal lymphoma and 10% of malignant salivary gland tumours. Most primary salivary gland lymphomas are B marginal zone lymphomas arising on a background of sialadenitis associated with autoimmune disorders such as Sjorgen's syndrome. Primary T cell lymphoma of the salivary gland is rare. This report describes a case of primary T cell lymphoma arising in the parotid gland of an elderly white man, which was notable for its striking resemblance to a B cell extranodal marginal zone lymphoma. Immunohistochemistry and gene rearrangement studies confirmed the clonal T cell nature of the tumour. There was no molecular evidence of Epstein-Barr virus (EBV) infection of neoplastic or surroundings cells. Only 14 cases of primary T cell lymphoma of the salivary glands have been recorded in the literature, most being from the Orient and having extremely variable prognosis. Those with a T/natural killer cell phenotype are associated with EBV infection. This case highlights the fact that T cell lymphoma in the salivary gland can mimic closely the morphological features of B cell extranodal marginal zone lymphoma. 相似文献
82.
Murray Thomson Eng Cheng Chan Joanne Davies John Falconer Gemma Madsen Simon Geraghty Roger Smith 《Neuroscience letters》1990,110(3):343-348
It is not certain which protein kinase (A, C or both) is involved in the acute phase of β-endorphin (β-EP) release stimulated in the corticotrope by vasopressin (VP) and corticotropin-releasing factor (CRF). We have employed an isolated ovine anterior pituitary cell superfusion system to determine the dynamic effects of forskolin, a protein kinase A (PKA) stimulator, and phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator. Both secretagogues stimulated β-EP release within 5 min and therefore both PKA and PKC are potential mediators of the acute phase of hormonal stimulation of the corticotrope. Pretreatment with PMA specifically desensitized the pituitary cell columns to subsequent PMA exposure while not significantly altering sensitivity to forskolin or 50 mM KCl. 相似文献
83.
This study examines harmaline-induced changes in 5′-nucleotidase (5′-ND) activity in cerebellar fractions from rats with an intact inferior olive (IO) or prior destruction of the IO by 3-acetylpyridine (3-AP) intoxication. Harmaline markedly increased 5′-ND activity in the crude homogenate (P<0.05) and P2 fraction (P<0.001) of cerebella from rats with an intact IO. This increase was absent in the P1, P3 and S3 fractions and it was abolished by 3-AP olivectomy. It was also absent in basal ganglia P2 fractions. Since harmaline produces rhythmic complex spike discharges of Purkinje cells by activating IO neurons [4, 18], these data suggest that climbing fiber activation per se increases 5′-ND activity in the P2 fraction. This raises the possibility that a climbing fiber-induced local increase in 5′-ND activity at parallel fiber-Purkinje cell synapses results in a local increase in adenosine concentration. This may account for climbing fiber-evoked suppression of simple spike activity [12, 13, 28]. 相似文献
84.
Social Security spends $135 million yearly, contracting with physicians to provide consultative examinations for disability applicants. However, little is known about who these physicians are or how they view the determination of impairment. We surveyed a random sample of 153 physicians from North Carolina who performed consultative examinations for the North Carolina Disability Determinations Agency in 1983 (the consultative group), and a randomly selected group of 165 physicians of similar medical specialties (the comparison group). Response rates were 75% for the consultative group and 66% for the comparison group. Most consultative physicians (63%) performed fewer than 6 examinations per month. Characteristics of the consultative physicians were similar to the comparison group. Both groups were skeptical of the claims of disability applicants; 48% of the consultative and 55% of the comparison group thought that a majority of applicants could be employed. Of the consultative physicians, 53% indicated that they had learned little about disability programs from any source. Most consultative physicians (58%) judged it "almost impossible" to determine impairment on the basis of a single office examination. However, consultative physicians were less likely than the comparison group to view Social Security as difficult to work with (25% vs. 54%; P less than 0.01). Agencies that determine disability ask physicians to perform a task for which they feel ill prepared and have little special knowledge. 相似文献
85.
E. Christopher Ellison M.D. Michael E. Van Aman M.D. Larry C. Carey M.D. 《World journal of surgery》1984,8(6):862-871
Pancreatic resection for pancreatic and periampullary cancer between 1969 and 1975 at The Ohio State University Hospitals had an associated operative mortality rate of 30% and a morbidity rate of 80%. Transhepatic biliary decompression (THD) has been accepted as a method of preoperative risk reduction in the deeply jaundiced patient and an alternative to surgical biliary decompression. The use of preoperative THD in pancreatic and periampullary cancer was examined. Of 44 patients with bilirubin greater than 10 mg/100 ml, 17 had radical resection (THD=7, no THD=10), and 27 had palliative operation (THD=17, no THD=10). Preoperative serum bilirubin in the THD group was 7.3±1.0 compared to 16.3 ±1.5 in the no THD group (p < 0.05). Operative morbidity rate was: radical surgery: THD (40%), no THD (70%); palliative surgery: THD (18%), no THD (20%). Operative mortality rate was: radical surgery: THD (28%), no THD (60%); palliative surgery: THD (6%), no THD (0%). Catheter-related complications were minimal. Preoperative THD tends to reduce the risk of curative resection for pancreatic and periampullary cancer, but does not alter the outcome of palliative surgery. Long-term THD may be an alternative if palliative surgical biliary decompression either fails or is not technically possible in the patient with unresectable cancer.
Resumen Se ha agudizado el debate relativo al papel de la resección curativa en el tratamiento del carcinoma pancreático y periampular. Mucha de la discusión se deriva de la excesiva morbilidad y mortalidad de la pancreatoduodenectomía y de la pancreatectomía total. Las cifras sobrepasan el porcentaje de supervivencia a 5 anos en todas las series mayores, y en algunos reportes la mortalidad operatoria es igual o mayor que el porcentaje de pacientes que sobreviven un año.La resección pancreática para cáncer pancreático y periampular entre los años 1969 y 1975 en los Hospitales de la Universidad del Estado de Ohio estuvo asociada con una mortalidad de 30% y una morbilidad de 80%. La descompresión biliar transhepática (DBT) ha sido aceptada como un método de reducción preoperatoria del riesgo quirúrgico en los pacientes intensamente ictéricos y como una alternativa a la descompresión biliar quirúrgica. El uso de la DBT preoperatoria en el cancer pancreático y periampular fué analizado. De 44 pacientes con bilirrubina mayor de 10 mg/100 ml, 17 fueron sometidos a resección radical (DBT = 7, no DBT = 10), y 27 tuvieron una operación paliativa (DBT = 17, no DBT = 10). La bilirrubina sérica en el grupo con DBT fué de 7.3±1.0, comparada con 16.3±1.5 en el grupo sin DBT (p < 0.05). La siguiente fué la morbilidad operatoria: cirugía radical: DBT 40%, no DBT 70%; cirugía paliativa: DBT 18%, no DBT 20%. La siguiente fué la mortalidad operatoria: cirugía radical: DPT 28%, no DPT 60%; cirugía paliativa: DBT 6%, no DBT 0. La DBT preoperatoria tiende a reducir el riesgo de la resección curativa para cáncer pancreático y periampular, pero no modiflca el resultado de la cirugía paliativa. La DBT prolongada puede ser una alternativa si la descompresión biliar quirúrgica falla o no es técnicamente posible en el paciente con cáncer no resecable.
Résumé La résection pancréatique pour cancer périampullaire ou pour cancer du pancréas entre 1969 et 1975 à Ohio State University Hospital accuse une mortalité opératoire de 30% et une morbidité de 80%. Le drainage biliaire transhépatique (transhepatic biliary decompression: T.H.D.), en présence de ces résultats, a été employé à titre pré-opératoire pour diminuer les risques de l'intervention chez les malades très ictériques et comme alternative au drainage biliaire chirurgical.Chez 44 malades qui présentaient un taux de bilirubine supérieur à 10 mg/dl, 17 ont subi une exérèse (7 après drainage transhépatique, 10 sans drainage transhépatique), 27 ont été traités par une intervention palliative (17 après drainage, 10 sans drainage). Le taux de bilirubine pré-opératoire fut ramené à 7.3±10 chez les malades drainés alors qu'il atteignait 16.3± 1.5 chez les malades qui n'avaient pas subi de drainage préalable.La morbidité opératoire fut en cas de chirurgie radicale de 40% après drainage et de 70% en l'absence de drainage; en cas de chirurgie palliative elle fut de 18% après drainage et de 20% en l'absence de drainage. La mortalité opératoire fut en cas de chirurgie radicale de 28% après drainage et de 60% en l'absence de drainage; en cas de chirurgie palliative elle fut de 6% après drainage et de 0% en l'absence de drainage. Les complications du drainage sont très rares. En un mot le drainage biliaire pré-opératoire réduit les risques de l'exérèse des cancers pancréatiques et des cancers périampullaire mais elle est sans influence en cas d'intervention palliative. Le drainage biliaire transhépatique prolongé offre une alternative au drainage chirurgical lorsque celui-ci échoue ou quand le cancer ne peut être réséqué.相似文献
86.
Improving health care for disabled people in COVID-19 and beyond: Lessons from Australia and England
Anne Kavanagh Helen Dickinson Gemma Carey Gwynnyth Llewellyn Eric Emerson George Disney Chris Hatton 《Disability and health journal》2021,14(2):101050
COVID-19 has exacerbated pre-existing difficulties children and adults with disability face accessing quality health care. Some people with disability are at greater risk of contracting COVID-19 because they require support for personal care and are unable to physically distance, e.g. those living in congregate settings. Additionally, some people with disability have health conditions that put them at higher risk of poor outcomes if they become infected. Despite this, governments have been slow to recognise, and respond to, the unique and diverse health care needs of people with disability during COVID-19. While some countries, including Australia, have improved access to high-quality health care for people with disability others, like England, have failed to support their citizens with disability. In this Commentary we describe the health care responses of England and Australia and make recommendations for rapidly improving health care for people with disability in the pandemic and beyond. 相似文献
87.
Francesca Snchez-Martínez Silvia Brugueras Gemma Serral Sara Valmayor Olga Jurez María Jos Lpez Carles Ariza 《Nutrients》2021,13(2)
Childhood obesity has increased worldwide over the past four decades. This quasi-experimental study aimed to assess the effectiveness of a multicomponent and multilevel school-based intervention (POIBA) at 3 years of follow-up. The nutrition intervention focused on food groups, food pyramid, nutrients, portions, and balanced menus. In total, 3624 children participated in the study. Anthropometric measurements and information on food frequency and behavior, physical activity, and daily screen use were collected in the intervention (IG) and comparison group (CG). Positive unadjusted changes toward adherence to recommendations were found for water, meat, sweets, and fried potato consumption, proper breakfast, not having dinner in front of the TV, out-of-school physical activity, and daily screen use. Three scores were used to calculate the proportion of children making more than one change to improve healthy habits regarding physical activity (global Activity score), nutrition (global Nutrition score), and both (global score). Students exposed to the intervention had a significantly better global Activity score (16.2% IG vs. 11.9% CG; p = 0.012) and Global score (63.9% IG vs. 58.5% CG; p = 0.025). Intervention effects on obesity incidence at 3-year follow-up lost significance but maintained the positive trend. In conclusion, school-based interventions including a family component could be useful to address the childhood obesity problem. 相似文献
88.
Gemma M. J. Taylor Katherine Sawyer David Kessler Marcus R. Munaf Paul Aveyard Alison Shaw 《Health expectations》2021,24(2):411
BackgroundTobacco smoking rates are significantly higher in people with common mental illness compared to those without. Smoking cessation treatment could be offered as part of usual outpatient psychological care, but currently is not.ObjectiveTo understand patient and health care professionals'' views about integrating smoking cessation treatment into outpatient psychological services for common mental illness.DesignQualitative in‐depth interviews, with thematic analysis.ParticipantsEleven Improving Access to Psychological Therapies (IAPT) psychological wellbeing practitioners (PWPs), six IAPT patients, and six stop smoking advisors were recruited from English smoking cessation, and IAPT services.ResultsPatients reported psychological benefits from smoking, and also described smoking as a form of self‐harm. Stop smoking advisors displayed therapeutic pessimism and stigmatizing attitudes towards helping people with mental illness to quit smoking. PWPs have positive attitudes towards smoking cessation treatment for people with common mental illness. PWPs and patients accept evidence that smoking tobacco may harm mental health, and quitting might benefit mental health. PWPs report expertise in helping people with common mental illness to make behavioural changes in the face of mood disturbances and low motivation. PWPs felt confident in offering smoking cessation treatments to patients, but suggested a caseload reduction may be required to deliver smoking cessation support in IAPT.ConclusionsIAPT appears to be a natural environment for smoking cessation treatment. PWPs may need additional training, and a caseload reduction. Integration of smoking cessation treatment into IAPT services should be tested in a pilot and feasibility study.Patient or public contributionService users and members of the public were involved in study design and interpretation of data. 相似文献
89.
Kelly C. Young-Wolff Julia Wei Nicole Varnado Normelena Rios Mary Staunton Carey Watson 《Women's health issues》2021,31(2):100-106
BackgroundThis study examined whether adverse childhood experiences (ACEs) are associated with increased risk of having an unwanted or mistimed pregnancy.MethodsWomen in two medical centers within an integrated health system were screened for ACEs during standard prenatal care (N = 745). Multinomial multivariable logistic regression analyses examined the associations of ACEs (count and type) with pregnancy intentions, adjusting for covariates.ResultsOverall, 58.3% of pregnant women reported no ACEs, 19.1% reported one ACE, and 22.7% reported two or more ACEs; 76.2% reported wanting to get pregnant, 18.5% reported wanting to get pregnant but not at this time (i.e., mistimed pregnancy), and 5.2% reported not wanting to get pregnant at all (i.e., unwanted pregnancy). Having two or more (vs. 0) ACEs was associated with higher odds of an unwanted pregnancy (odds ratio, 2.60; 95% confidence interval, 1.19–5.68). Further, childhood loss of parent (odds ratio, 2.20; 95% confidence interval, 1.03–4.71) and neglect (odds ratio, 5.67; 95% confidence interval, 1.72–18.72) were each associated with higher odds of an unwanted pregnancy in separate analyses. ACEs count and type were not significantly associated with having a mistimed pregnancy.ConclusionsAmong women screened for ACEs during standard prenatal care, ACEs were associated with increased odds of having an unwanted pregnancy, but not a mistimed pregnancy. Additional research is needed to better understand the mechanisms through which ACEs and other individual, social, and contextual factors impact pregnancy intentions to better support women and provide appropriate resources to help prevent unintended pregnancies. 相似文献
90.
Vemulakonda Vijaya M. Sevick Carter Juarez-Colunga Elizabeth Chiang George Janzen Nicolette Saville Alison Adams Parker Beltran Gemma King Jordon Ewing Emily Kempe Allison 《International urology and nephrology》2021,53(8):1485-1495
International Urology and Nephrology - Studies based on administrative databases show that infant pyeloplasty is associated with minority race/ethnicity but lack clinical data that may influence... 相似文献