全文获取类型
收费全文 | 8552篇 |
免费 | 484篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 96篇 |
儿科学 | 309篇 |
妇产科学 | 274篇 |
基础医学 | 822篇 |
口腔科学 | 296篇 |
临床医学 | 822篇 |
内科学 | 2037篇 |
皮肤病学 | 244篇 |
神经病学 | 632篇 |
特种医学 | 314篇 |
外科学 | 1471篇 |
综合类 | 110篇 |
一般理论 | 7篇 |
预防医学 | 479篇 |
眼科学 | 199篇 |
药学 | 470篇 |
中国医学 | 37篇 |
肿瘤学 | 458篇 |
出版年
2024年 | 12篇 |
2023年 | 108篇 |
2022年 | 184篇 |
2021年 | 399篇 |
2020年 | 264篇 |
2019年 | 363篇 |
2018年 | 351篇 |
2017年 | 256篇 |
2016年 | 271篇 |
2015年 | 280篇 |
2014年 | 393篇 |
2013年 | 421篇 |
2012年 | 725篇 |
2011年 | 715篇 |
2010年 | 418篇 |
2009年 | 359篇 |
2008年 | 530篇 |
2007年 | 543篇 |
2006年 | 427篇 |
2005年 | 391篇 |
2004年 | 333篇 |
2003年 | 316篇 |
2002年 | 264篇 |
2001年 | 88篇 |
2000年 | 79篇 |
1999年 | 69篇 |
1998年 | 37篇 |
1997年 | 42篇 |
1996年 | 38篇 |
1995年 | 24篇 |
1994年 | 20篇 |
1993年 | 28篇 |
1992年 | 22篇 |
1991年 | 30篇 |
1990年 | 31篇 |
1989年 | 23篇 |
1988年 | 25篇 |
1987年 | 22篇 |
1986年 | 16篇 |
1985年 | 27篇 |
1984年 | 24篇 |
1983年 | 16篇 |
1982年 | 10篇 |
1981年 | 11篇 |
1980年 | 8篇 |
1979年 | 13篇 |
1978年 | 9篇 |
1977年 | 8篇 |
1974年 | 7篇 |
1973年 | 5篇 |
排序方式: 共有9077条查询结果,搜索用时 15 毫秒
31.
Munaza Fatima Santosh Kumar Mudassar Hussain Naveed Masood Memon Anum Vighio Muhammad Asif Syed Ambreen Chaudhry Zakir Hussain Zeeshan Iqbal Baig Mirza Amir Baig Rana Jawad Asghar Aamer Ikram Yousef Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures. 相似文献
32.
Saurabh Kumar Bhushan Shah Ashok Johari Rashid Anjum Devansh Garg Rashmi Salhotra Asha Tyagi Amir Maroof Khan Anil Kumar Jain 《Indian Journal of Orthopaedics》2021,55(2):506
Covid-19 is a respiratory disease caused by coronavirus 2 (SARS-CoV-2) first identified in Wuhan, China (December 2019). The disease rapidly crossed the barrier of countries, continents and spread globally. Non-pharmaceutical measures such as social distancing, face mask, frequent hand washing and use of sanitizer remained the best available option to prevent the spread of disease. OPD, IPD admissions, elective O. Ts were curtailed. Orthopedic care was only limited to emergency and semi-urgent procedures like necrotizing fasciitis, open fracture, and compartment syndrome. These measures were taken to preserve infrastructure and manpower to manage covid-19 pandemic. The children were thought to have a low susceptibility to covid-19 as compared to an adult. Deferring the patient during pandemic has led to high orthopedic disease burden, morbidity and disease-related sequelae, hence elective care must be resumed with modified hospital infrastructure. Resumption of elective/emergent orthopedic care should be slow, phasic and strategic, much similar to unlocking. Cases must be stratified depending on covid status and severity. Dedicated O.Ts with neutral/negative pressure and HEPA filter for covid positive and suspected patients are to be used. All symptomatic and suspected patients should be investigated for covid-19 by RT-PCR, blood counts and CT scan. Regional anaesthesia should be preferred to General anaesthesia. Power drill/saw/burr/pulse lavage should be minimized to avoid aerosol generation. Postoperatively continuous surveillance and monitoring to be done for covid related symptoms. Medical institutes rapidly shifted to the online mode of education. Blended learning (virtual & physical) and imparting skills have to be continued in post covid phase with equitable distribution of teaching hours to students of different years. 相似文献
33.
Vikas S. Gupta Amir M. Khan Ashley H. Ebanks Pamela A. Lally Kevin P. Lally Matthew T. Harting 《Journal of pediatric surgery》2021,56(4):697-699
PurposeThere is a known association between Cornelia de Lange syndrome (CdLS) and congenital diaphragmatic hernia (CDH), with CDH being the cause of death in 5%–20% of CdLS cases. We aimed to identify and describe patients with CDLS and CDH. We hypothesized that CdLS would be associated with high-risk CDH and poor outcomes.MethodsCDH Study Group patients from 1995 to 2019 were included. Those with CdLS were reviewed retrospectively. Rates of repair and outcomes were compared between patients with and without CdLS.ResultsWe identified 9,251 CDH patients. Of those, 21 had confirmed CdLS. CdLS patients had a lower birth weight (2.2 ± 0.57 kg) than non-CdLS patients (2.9 ± 0.64 kg) (p < 0.001). 5-min Apgar scores were lower in CdLS patients (6, 4–7) than non-CdLS patients (7, 5–8) (p = 0.014). Only 33% of CdLS patients underwent diaphragmatic repair compared to 84.2% of non-CdLS patients (p < 0.001). Mortality was 76% for CdLS patients compared with 29% for non-CdLS patients (p < 0.001). Of the 7 CdLS patients who underwent repair, 5 survived to hospital discharge.ConclusionsInfants with CdLS and CDH have a poor prognosis. However, CdLS patients who undergo repair can survive to discharge; therefore, the concomitant diagnosis of CdLS and CDH is not necessarily a contraindication to repair. Early recognition of these anomalies can assist with counseling and prognostication.Type of studyRetrospective comparative studyLevel of evidenceIII 相似文献
34.
Kellie Martens Aaron Hamann Lisa R. Miller-Matero Chazlyn Miller Aaron J. Bonham Amir A. Ghaferi Arthur M. Carlin 《Surgery for obesity and related diseases》2021,17(2):366-371
BackgroundFindings regarding longer term symptoms of depression and the impact of depression on outcomes such as weight loss and patient satisfaction, are mixed or lacking.ObjectivesThis study sought to understand the relationship between depression, weight loss, and patient satisfaction in the two years after bariatric surgery.SettingThis study used data from a multi-institutional, statewide quality improvement collaborative of 45 different bariatric surgery sites.MethodsParticipants included patients (N = 1991) who underwent Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) between 2015–2018. Participants self-reported symptoms of depression (Patient Health Questionnaire-8 [PHQ-8]), satisfaction with surgery, and weight presurgery and 1 year and 2 years postsurgery.ResultsCompared to presurgery, fewer patients’ PHQ-8 scores indicated clinically significant depression (PHQ-8≥10) at 1 year (P < .001; 14.3% versus 5.1%) and 2 years postsurgery (P < .0001; 8.7%). There was a significant increase in the prevalence of clinical depression from the first to second year postsurgery (P < .0001; 5.1% versus 8.7%). Higher PHQ-8 at baseline was related to less weight loss (%Total Weight Loss [%TWL] and %Excess Weight Loss [%EWL]) at 1 year postsurgery (P < .001), with a trend toward statistical significance at 2 years (P = .06). Postoperative depression was related to lower %TWL and %EWL, and less reduction in body mass index (BMI) at 1 year (P < .001) and 2 years (P < .0001). Baseline and postoperative depression were associated with lower patient satisfaction at both postoperative time points.ConclusionsThis study suggests improvements in depression up to 2 years postbariatric surgery, although it appears that the prevalence of depression increases after the first year. Depression, both pre- and postbariatric surgery, may impact weight loss and patient satisfaction. 相似文献
35.
Rabea Asleh Hilmi Alnsasra Amir Lerman Alexandros Briasoulis Naveen L. Pereira Brooks S. Edwards Takumi Toya John M. Stulak Alfredo L. Clavell Richard C. Daly Sudhir S. Kushwaha 《American journal of transplantation》2021,21(2):626-635
We have previously described the use of sirolimus (SRL) as primary immunosuppression following heart transplantation (HT). The advantages of this approach include attenuation of cardiac allograft vasculopathy (CAV), improvement in glomerular filtration rate (GFR), and reduced malignancy. However, in some patients SRL may cause significant proteinuria. We sought to investigate the prognostic value of proteinuria after conversion to SRL. CAV progression and adverse clinical events were studied. CAV progression was assessed by measuring the Δ change in plaque volume (PV) and plaque index (PI) per year using coronary intravascular ultrasound. Proteinuria was defined as Δ urine protein ≥300 mg/24 h at 1 year after conversion to SRL. Overall, 137 patients were analyzed (26% with proteinuria). Patients with proteinuria had significantly lower GFR (P = .005) but similar GFR during follow-up. Delta PV (P < .001) and Δ PI (P = .001) were significantly higher among patients with proteinuria after adjustment for baseline characteristics. Multivariate Cox regression analysis showed higher all-cause mortality (hazard ratio 3.8; P = .01) with proteinuria but similar risk of CAV-related events (P = .61). Our results indicate that proteinuria is a marker of baseline renal dysfunction, and that HT recipients who develop proteinuria after conversion to SRL have less attenuation of CAV progression and higher mortality risk. 相似文献
36.
There are no guidelines to help psychiatric researchers statistically adjust for missing data. We discuss the problems resulting from missing values, and illustrate some of them with examples from our work. Using structured instruments, we obtained clinical information from 241 patients. Some instrument items were not rated, and these did not occur randomly: hallucinations and delusions were most frequently unrated, especially in chronic schizophrenics, and patients with high scores for other psychopathology. Systematically assigning an intermediate value between present and absent to nonrated items was a satisfactory solution, unaffected by nonrandom missing values. This simple solution was equivalent to a complicated one (vectoring) in discriminating patients. When relationships between variables are linear, we recommend the intermediate value method as a practical solution to missing values. We stress that missing values do not mean missing information, and the most common response to missing values (dropping subjects) is least informative. 相似文献
37.
J. Amir M. D. Liora Harel M. D. Tal Eidlitz-Markus M. D. I. Varsano M. D. 《Infection》1995,23(6):389-390
Summary Toxocariasis in children is usually an asymptomatic infection and those with clinical illness have non-specific systemic or local manifestations. We present a 24-month-old boy with bilateral lymphedema of the feet as the main clinical manifestation of toxocariasis. The child presented with limping and nonpitting edema of both feet. Laboratory investigation revealed leucocytosis of <20,000/mm3 with a differential count of <50% eosinophils. No other cause of edema was found. The ELISA for toxocariasis revealed a high titer of 1:4,096. The limping and the lymphedema disappeared during the third week of his illness. We suggest that toxocariasis should be considered as a possible cause of lymphedema and eosinophilia in young children.Zusammenfassung Die Toxocariasis nimmt bei Kindern in der Regel einen asymptomatischen Verlauf. Wenn Krankheitszeichen auftreten, handelt es sich um unspezifische Allgemeinsymptome oder lokale Symptome. Wir berichten über einen 24 Monate alten Jungen, bei dem ein bilaterales Lymphödem der Füße die Hauptmanifestation der Toxocariasis war. Das Kind hinkte und hatte an beiden Füßen ein nicht dellenbildendes Ödem. Dabei bestand eine Leukozytose von >20 000/mm3 mit >50% Eosinophilen im Differentialblutbild. Andere Ursachen für das Ödem waren nicht zu finden. Der ELISA für Toxocariasis ergab einen hohen Titer von >1:4 096. Hinken und Lymphödem verschwanden im Verlauf von drei Wochen. Wir verweisen auf die Möglichkeit einer Toxocariasis als mögliche Ursache für Lymphödem und Eosinophilie bei kleinen Kindern.
Lymphödem als Primärsymptom einer Toxocariasis相似文献
38.
Tizabi Y Overstreet DH Rezvani AH Louis VA Clark E Janowsky DS Kling MA 《Psychopharmacology》1999,142(2):193-199
Epidemiological studies indicate a high incidence of cigarette smoking among depressed individuals. Moreover, individuals
with a history of depression have a much harder time giving up smoking. It has been postulated that smoking may reflect an
attempt at self-medication with nicotine by these individuals. Although some animal and human studies suggest that nicotine
may act as an antidepressant, further verification of this hypothesis and involvement of nicotinic cholinergic system in depressive
symptoms is required. Flinders Sensitive Line (FSL) rats have been proposed as an animal model of depression. These rats,
selectively bred for their hyperresponsiveness to cholinergic stimulation, show an exaggerated immobility in the forced swim
test compared to their control Flinders Resistant Line (FRL) rats. Acute or chronic (14 days) administration of nicotine (0.4 mg/kg
SC) significantly improved the performance of the FSL but not the FRL rats in the swim test. The effects of nicotine on swim
test were dissociable from its effects on locomotor activity. Moreover, the FSL rats had significantly higher [3H]cytisine binding (selective for the α4β2 nicotinic receptor subtype) but not [125I]alpha-bungarotoxin binding (selective for the α7 subtype) in the frontal cortex, striatum, midbrain and colliculi compared to FRL rats. These data strongly implicate the
involvement of central nicotinic receptors in the depressive characteristics of the FSL rats, and suggest that nicotinic agonists
may have therapeutic benefits in depressive disorders.
Received: 9 June 1998/Final version: 6 August 1998 相似文献
39.
Joel M. Childers MD Amir Nasseri MD Earl A. Surwit MD 《American journal of obstetrics and gynecology》1996,175(6):1451-1459
OBJECTIVE: Our aim was to evaluate the feasibility and applicability of operative laparoscopy in the management of adnexal masses that do not meet the standard serum CA 125 and ultrasonographic criteria for benignity. STUDY DESIGN: One hundred thirty-eight patients underwent operative laparoscopy for removal of suspicious adnexal masses. The CA 125 level was >35 mIU/ml in 39 of 138 (28%) patients; ultrasonographic findings were abnormal in 127 of 138 (92%); masses were >10 cm in 43 of 138 (32%) of patients. RESULTS: Malignancies were discovered in 14% (19/138) of patients. Eight percent (11/138) of the procedures were converted to laparotomy, six because of inability to dissect the mass laparoscopically and five for staging or debulking of carcinoma. Operative times ranged from 25 to 210 minutes, with a mean of 86. Three major complications were encountered-an enterotomy and a lacerated vena cava, both of which were repaired laparoscopically, and a small bowel herniation through a lateral port site that required reoperation. Hospital stays ranged from 0 to 11 days, with a mean of 1.5. In two patients with "apparent" stage I adnexal carcinomas recurrence was diagnosed 6 and 38 months after surgery. CONCLUSIONS: Laparoscopic management of suspicious adnexal masses is technically feasible, with a low rate of morbidity and a short hospital stay. Adnexal carcinomas can be identified and managed appropriately with staging and complete resection as indicated. (Am J Obstet Gynecol 1996;175:1451-9.) 相似文献
40.
The present study investigated the temporal structure of sleep propensity during 48 hours using an ultrashort 7-min sleep/13-min wake cycle. Eight subjects were tested under two experimental conditions of either attempting sleep, or resisting sleep after a monitored night in the laboratory. Electrophysiological recordings were carried out during the 7-min trials. The temporal structure and the overall level of sleepiness of the 48-hour sleep propensity functions calculated from the amount of total sleep in each trial revealed a high within-subjects stability. This was found both across the two days of the study within conditions, and across conditions. Also, diurnal levels of sleepiness were systematically related to nocturnal sleep parameters. Subjects having short nocturnal sleep latencies and higher sleep efficiencies slept more during the day. It is proposed that the structure and level of the sleep propensity function can be used to characterize individuals along two dimensions of somnotypology: "morningness-eveningness" and "sleepy-alert." 相似文献