全文获取类型
收费全文 | 12985篇 |
免费 | 700篇 |
国内免费 | 76篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 263篇 |
妇产科学 | 334篇 |
基础医学 | 1760篇 |
口腔科学 | 481篇 |
临床医学 | 1088篇 |
内科学 | 3677篇 |
皮肤病学 | 328篇 |
神经病学 | 1267篇 |
特种医学 | 322篇 |
外科学 | 1682篇 |
综合类 | 59篇 |
一般理论 | 2篇 |
预防医学 | 685篇 |
眼科学 | 189篇 |
药学 | 673篇 |
中国医学 | 35篇 |
肿瘤学 | 835篇 |
出版年
2023年 | 96篇 |
2022年 | 206篇 |
2021年 | 440篇 |
2020年 | 222篇 |
2019年 | 294篇 |
2018年 | 430篇 |
2017年 | 265篇 |
2016年 | 337篇 |
2015年 | 346篇 |
2014年 | 508篇 |
2013年 | 640篇 |
2012年 | 1052篇 |
2011年 | 1067篇 |
2010年 | 591篇 |
2009年 | 591篇 |
2008年 | 945篇 |
2007年 | 947篇 |
2006年 | 879篇 |
2005年 | 771篇 |
2004年 | 697篇 |
2003年 | 618篇 |
2002年 | 628篇 |
2001年 | 67篇 |
2000年 | 60篇 |
1999年 | 88篇 |
1998年 | 103篇 |
1997年 | 104篇 |
1996年 | 88篇 |
1995年 | 69篇 |
1994年 | 68篇 |
1993年 | 61篇 |
1992年 | 41篇 |
1991年 | 43篇 |
1990年 | 40篇 |
1989年 | 36篇 |
1988年 | 30篇 |
1987年 | 19篇 |
1986年 | 23篇 |
1985年 | 15篇 |
1984年 | 35篇 |
1983年 | 27篇 |
1982年 | 22篇 |
1981年 | 21篇 |
1980年 | 18篇 |
1979年 | 9篇 |
1978年 | 12篇 |
1977年 | 18篇 |
1975年 | 8篇 |
1974年 | 11篇 |
1969年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Walter Daghino MD Luigi Milano MD Sergio Ronco MD Giorgio Ronco MD Angelo Dettoni MD Massimo Cartesegna MD 《The Journal of foot and ankle surgery》2003,42(3):155-160
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05). 相似文献
32.
Gilberto Goissis Sergio Akinobu Yoshioka Domingo Marcolino Braile & Vladimir Donizeti Aparecido Ramirez 《Artificial organs》1998,22(3):210-214
This work describes the results of the controlled crosslinking of collagen matrices by glutaraldehyde based on a double protection strategy, glutaraldehyde acetals and lysine protonation due to the acidic conditions of acetal formation. Materials crosslinked by this approach were characterized by thermal stability comparable to those obtained by conventional procedures with mechanical properties expected for bioprosthesis manufacture and with a higher stability toward collagenase hydrolysis. The integrity of the microfibrillar structure was confirmed by optical and scanning electronic microscopy. The results indicate that the glutaraldehyde acetals procedure may be of potential use for the crosslinking of bovine pericardium used in the manufacture of bioprosthetic devices. Advantages may be related to the production of materials with homogeneous crosslinking distributions, associated with better definition in the nature of the chemical link that they introduce, due to a better distribution of glutaraldehyde within the tissue matrix before the crosslinking reaction is allowed to occur. As a result, materials with improved biological and mechanical properties are expected. 相似文献
33.
Valentina Coia Barbara Sansonetti Giorgio Paoli Sergio Tofanelli Gabriella Spedini Giovanni Destro‐Bisol 《American journal of human biology》2002,14(1):9-14
Ten protein coding loci (6‐PGD, A1‐AT, ACP1, CaII, ESD, GC, GPX1, Hbβ, PGM1, and TF) were analyzed in the Mbenzele Pygmies from the Central African Republic. The frequency data were used to calculate the genetic distances between Mbenzele Pygmies and other African groups. In the principal coordinate plot of FST genetic distances, the Mbenzele cluster together with other Pygmies of the western cluster, the Biaka from C.A.R., Gielli from Cameroon, and Babinga from Congo. By contrast, they are considerably distanced from other Pygmy groups of the eastern cluster (Twa from Rwanda, Mbuti from Zaire). Genetic distances obtained using protein loci were compared with those based on microsatellite loci. The two distance matrices are insignificantly correlated (r = 0.268; one tail probability = 0.332), and the main difference is in the higher genetic affinity between the Mbenzele and Biaka Pygmies observed at the protein level. Although reasons underlying the discrepancy between inter‐populational variation at protein and DNA loci are not established with certainty, the comparison suggests that the genetic distance between the Mbenzele and Biaka Pygmies at microsatellite loci could have been shaped by genetic drift. Am. J. Hum. Biol. 14:9–14, 2002.© 2002 Wiley‐Liss, Inc. 相似文献
34.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
35.
36.
Catalina Betancur Carmen Sandi Sergio Vitiello Jos Borrell Carmen Guaza Pierre J. Neveu 《Brain research》1992,589(2):302-306
Asymmetry in brain modulation of the immune system has been previously described. In mice, paw preference has been shown to be associated with immune reactivity but the mechanisms involved in such an association are not yet known. The autonomic nervous system and the neuroendocrine system are considered as major candidates for neural influences on the immune system. In the present study, the activity of the hypothalamic-pituitary-adrenal (HPA) axis of adult female mice selected for paw preference (left-handers vs. right-handers) was assessed by measuring both adrenocorticotropic hormone (ACTH) and corticosterone plasma levels, as well as the in vitro responses of hypothalamus and adrenocortical cells to various hormone releasing stimuli. The results reported here showed no difference in the activity of the HPA axis between left- and right-handed mice, suggesting that this neuroendocrine axis is not implicated in the association between functional brain asymmetry and immune reactivity. However, our results do not exclude the possibility that the HPA axis could play a role in such an association under other circumstances, such as during development or stressful situations. 相似文献
37.
38.
Mete Isikoglu Kemal Ozgur Sergio Oehninger Sebahat Ozdem Murat Seleker 《Gynecological endocrinology》2006,22(5):256-260
BACKGROUND: We aimed to determine whether serum concentrations of anti-Müllerian hormone (AMH) can be used as a tool for prediction of the efficacy of sperm retrieval. METHODS: This was a prospective cohort observational study. AMH levels were determined in 47 men presenting for infertility evaluation. Group 1 consisted of 24 infertile patients diagnosed with non-obstructive azoospermia. Group 1 was further divided into two subgroups. The patients with spermatozoa in their testicular samples constituted group 1a (n = 13), while the patients with absence of spermatozoa constituted group 1b (n = 11). Twenty-three normozoospermic fertile men constituted group 2. Serum AMH was measured before obtaining testicular specimens. RESULTS: Testicular spermatozoa were recovered in 13 out of the 24 patients (54%). Demographic characteristics of the three groups were similar. The difference between serum AMH levels among the three groups did not reach statistical significance. CONCLUSIONS: We speculated that although AMH is secreted predominantly into the seminiferous tubules, studying serum samples might be more advantageous than seminal plasma because the presence of seminal proteases could influence AMH levels in the latter. However, our results did not demonstrate differences in serum concentrations of AMH between the studied groups. Studies with extended patient populations focusing on seminal plasma concentrations of AMH are warranted. 相似文献
39.
Everson L. A. Artifon Airton Z. Rodrigues Sergio Marques Bhawna Halwan Paulo Sakai Claudio Bresciani Atul Kumar 《Journal of gastrointestinal surgery》2007,11(12):1686-1691
Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate
diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required
do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may
be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents
at the same time as the initial laparoscopy.
Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment
of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome
measure was complications rates.
Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor
in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were
deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic
exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures
median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was
3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy
was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction,
and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal
anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified:
one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total
of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications.
Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This
option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct. 相似文献
40.
Sergio Luís Blay Sergio Baxter Andreoli Fábio Leite Gastal 《Annals of clinical psychiatry》2007,19(3):169-174
BACKGROUND: The main purpose of this study is to investigate the association of disturbed sleep, chronic physical pain and psychiatric morbidity in people aged 60 years and over. METHODS: A population-based random sample of 7040 household residents aged 60 years and over, was examined in a face-to-face interview. Painful medical conditions were assessed through questions evaluating medical treatment, hospitalizations, and consultations for medical problems. Disturbed sleep was assessed through questions concerning the presence of sleeping problems in the past 4 weeks. RESULTS: The overall prevalence of disturbed sleep is 33.7% (95% CI: 32.5-34.8) and the 6-month prevalence of any chronic pain was 76.2% (95% CI: 74.2-78.2%). A substantial burden of disturbed sleep is associated with the presence of physical pain morbidity, 42.5% for back pain to 49.7% for headaches. The prevalence of pain among persons with disturbed sleep ranges from 25.8% for gastrointestinal pain to 54.6% for joint pain. The presence of comorbid pain and disturbed sleep has an important disability impact as assessed by socioecomomic/professional data, health care utilization, self-rated health and physical activity. In logistic regression models, headaches, psychiatric morbidity, rural origin, Caucasians, self-rated health and number of chronic pain conditions were significantly associated with disturbed sleep after controlling for demographic variables and comorbidities. Age has a negative effect on sleep complaints. CONCLUSIONS: Disturbed sleep is highly comorbid with other pain conditions particularly headaches and psychiatric morbidity in later life. The combination of pain and disturbed sleep leads to important role disability and increased utilization of medical services. 相似文献