全文获取类型
收费全文 | 3042篇 |
免费 | 762篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 88篇 |
儿科学 | 120篇 |
妇产科学 | 44篇 |
基础医学 | 62篇 |
口腔科学 | 12篇 |
临床医学 | 1085篇 |
内科学 | 800篇 |
皮肤病学 | 131篇 |
神经病学 | 221篇 |
特种医学 | 103篇 |
外科学 | 567篇 |
综合类 | 27篇 |
预防医学 | 119篇 |
眼科学 | 95篇 |
药学 | 62篇 |
中国医学 | 1篇 |
肿瘤学 | 284篇 |
出版年
2024年 | 18篇 |
2023年 | 141篇 |
2022年 | 46篇 |
2021年 | 123篇 |
2020年 | 205篇 |
2019年 | 72篇 |
2018年 | 220篇 |
2017年 | 166篇 |
2016年 | 205篇 |
2015年 | 171篇 |
2014年 | 269篇 |
2013年 | 310篇 |
2012年 | 115篇 |
2011年 | 93篇 |
2010年 | 213篇 |
2009年 | 263篇 |
2008年 | 121篇 |
2007年 | 90篇 |
2006年 | 117篇 |
2005年 | 91篇 |
2004年 | 56篇 |
2003年 | 40篇 |
2002年 | 43篇 |
2001年 | 65篇 |
2000年 | 48篇 |
1999年 | 52篇 |
1998年 | 50篇 |
1997年 | 61篇 |
1996年 | 55篇 |
1995年 | 49篇 |
1994年 | 24篇 |
1993年 | 15篇 |
1992年 | 18篇 |
1991年 | 25篇 |
1990年 | 15篇 |
1989年 | 15篇 |
1988年 | 10篇 |
1986年 | 13篇 |
1985年 | 17篇 |
1984年 | 14篇 |
1983年 | 6篇 |
1978年 | 5篇 |
1976年 | 4篇 |
1975年 | 7篇 |
1974年 | 6篇 |
1969年 | 4篇 |
1958年 | 3篇 |
1955年 | 6篇 |
1954年 | 4篇 |
1949年 | 6篇 |
排序方式: 共有3821条查询结果,搜索用时 13 毫秒
31.
Caroline E. Fife MD ;Cem Buyukcakir MD ; Gordon H. Otto PhD ; Paul J. Sheffield PhD ; Robert A. Warriner III MD ; Tommy L. Love DO ; Jon Mader MD 《Wound repair and regeneration》2002,10(4):198-207
The objective of this retrospective analysis was to determine the reliability of transcutaneous oxygen tension measurement (TcPO2) in predicting outcomes of diabetics who underwent hyperbaric oxygen therapy for lower extremity wounds. Six hyperbaric facilities provided TcPO2 data under several possible conditions: breathing air, breathing oxygen at sea level, and breathing oxygen in the chamber. Overall, 75.6% of the patients improved after hyperbaric oxygen therapy. Baseline sea-level air TcPO2 identified the degree of tissue hypoxia but had little statistical relationship with outcome prediction because some patients healed after hyperbaric oxygen therapy despite very low prehyperbaric TcPO2 values. Breathing oxygen at sea level was unreliable for predicting failure, but 68% reliable for predicting success after hyperbaric oxygen therapy. TcPO2 measured in chamber provides the best single discriminator between success and failure of hyperbaric oxygen therapy using a cutoff score of 200 mmHg. The reliability of in-chamber TcPO2 as an isolated measure was 74% with a positive predictive value of 58%. Better results can be obtained by combining information about sea-level air and in-chamber oxygen. A sea-level air TcPO2 < 15 mmHg combined with an in-chamber TcPO2 < 400 mmHg predicts failure of hyperbaric oxygen therapy with a reliability of 75.8% and a positive predictive value of 73.3%. 相似文献
32.
Kelvin C. Lee MD Mark M. Altenau MD David R. Barnes MD Joseph M. Bernstein MD Nadim B. Bikhazi MD Frank A. Brettscheider DO Charles H. Caplan MD William A. Ditkowsky MD Craig F. Ingber MD Lee M. Klausner MD Maseih M. Moghaddassi MD 《Otolaryngology--head and neck surgery》2002,127(6):531-538
OBJECTIVE: Ionized field ablation, or coblation-assisted subtotal tonsillectomy, has been described as a new alternative technique for the management of tonsillar disease. This study was designed to review the incidence of complications in patients undergoing this procedure. STUDY DESIGN: A 10-surgeon retrospective chart review of the intraoperative and postoperative complications of patients undergoing ionized field ablation subtotal removal of tonsils was performed. Postoperative pain, dietary restrictions, and activity level were not reviewed. RESULTS: Of the 528 patients who underwent ionized field ablation of their tonsils, the incidence of intraoperative and postoperative complications compared favorably with those reported in retrospective studies in the literature for traditional subcapsular tonsillectomy. Significant postoperative bleeding occurred in less than 1%, and only 1 patient required surgical control of bleeding in the operating room. No patients required transfusions of any blood products. CONCLUSIONS: Ionized field ablation subtotal tonsillectomy may offer an alternative to traditional subcapsular tonsillar surgery with a decreased incidence of postoperative complications. Further study is necessary to establish the complication rate of this technique. 相似文献
33.
Identification and content validation of wound therapy clinical endpoints relevant to clinical practice and patient values for FDA approval. Part 1. Survey of the wound care community 下载免费PDF全文
Vickie R. Driver MS DPM FACFAS Lisa J. Gould MD PhD FACS Peggy Dotson RN BS Gary W. Gibbons MD FACS William W. Li MD William J. Ennis DO MBA Robert S. Kirsner MD PhD William H. Eaglstein MD Laura L. Bolton PhD Marissa J. Carter PhD MA 《Wound repair and regeneration》2017,25(3):454-465
Wounds that exhibit delayed healing add extraordinary clinical, economic, and personal burdens to patients, as well as to increasing financial costs to health systems. New interventions designed to ease such burdens for patients with cancer, renal, or ophthalmologic conditions are often cleared for approval by the U.S. Food and Drug Administration (FDA) using multiple endpoints but the requirement of complete healing as a primary endpoint for wound products impedes FDA clearance of interventions that can provide other clinical or patient‐centered benefits for persons with wounds. A multidisciplinary group of wound experts undertook an initiative, in collaboration with the FDA, to identify and content validate supporting FDA criteria for qualifying wound endpoints relevant to clinical practice (CP) and patient‐centered outcomes (PCO) as primary outcomes in clinical trials. As part of the initiative, a research study was conducted involving 628 multidisciplinary expert wound clinicians and researchers from 4 different groups: the interdisciplinary core advisory team; attendees of the Spring 2015 Symposium on Advanced Wound Care (SAWC); clinicians employed by a national network of specialty clinics focused on comprehensive wound care; and Association for the Advancement of Wound Care (AAWC) and Wound Healing Society (WHS) members who had not previously completed the survey. The online survey assessed 28 literature‐based wound care endpoints for their relevance and importance to clinical practice and clinical research. Fifteen of the endpoints were evaluated for their relevance to improving quality of life. Twenty‐two endpoints had content validity indexes (CVI) ≥ 0.75, and 15 were selected as meriting potential inclusion as additional endpoints for FDA approval of future wound care interventions. This study represents an important first step in identifying and validating new measurable wound care endpoints for clinical research and practice and for regulatory evaluation. 相似文献
34.
Mr‐derived cerebral spinal fluid hydrodynamics as a marker and a risk factor for intracranial hypertension in astronauts exposed to microgravity 下载免费PDF全文
35.
BACKGROUND CONTEXT: Paraspinal infections after zygapophyseal (facet) radiofrequency denervation (RFD) are a serious but rare complication of this procedure. We are aware of only one case report of an epidural abscess after facet joint injection. PURPOSE: To report post-procedure inflammatory changes after cervical facet RFD. STUDY DESIGN: Case report. PATIENT SAMPLE: A 35-year-old Caucasian female. METHODS: Retrospective case review. RESULTS: The patient underwent cervical RFD and was admitted to the hospital 7 days after her procedure with severe neck pain. Magnetic resonance imaging (MRI) with contrast revealed what appeared to be evidence of a paraspinal muscle abscess although blood tests were negative. She was treated with antibiotic therapy, yet she never developed systemic signs of infection. A follow-up MRI without contrast revealed no evidence of infection, and she was discharged home on hospital day 6. At her first follow-up visit, she was still experiencing scalp pain and paraspinal muscle spasm. During subsequent follow-up visits, she has continued to improve clinically without experiencing signs of infection. Another follow-up MRI 6 weeks after her discharge home revealed persistent minimal left paraspinal enhancement at C2-3, possibly representing post-procedure granulation tissue with no evidence of abscess. CONCLUSIONS: Post-procedural MRI findings after radiofrequency lesioning can resemble radiographic findings associated with a paraspinal abscess. Patients with radiographic findings consistent with abscess should only be treated if clinical signs or symptoms of systemic infection are present. 相似文献
36.
YVON F. BRYAN MD LAUREN K. HOKE BS THOMAS A. TAGHON DO † TODD G. NICK PhD ‡ YU WANG MS MAS STEPHANIE M. KENNEDY CRNA JAMES S. FURSTEIN CRNA CHARLES DEAN KURTH MD 《Paediatric anaesthesia》2009,19(7):672-681
Objectives: We compared three primary outcomes of pausing the magnetic resonance imaging (MRI) scan, emergence quality and respiratory complications.
Aim: To measure and compare the quality between sevoflurane and propofol in children undergoing MRI scans.
Background: No randomized controlled trial exists comparing the quality between sevoflurane and propofol for MRI.
Methods/Materials: Two hundred unpremedicated children (18 months to 7 years) scheduled for brain MRI scans were recruited. After induction with sevoflurane, children were randomized to receive sevoflurane [general anesthesia with sevoflurane (GAS)] via laryngeal mask airway (LMA) or propofol [general anesthesia with propofol (GAP)] bolus and infusion for their scan. The three primary outcomes of pausing the MRI scan (P), agitation (A), and respiratory complications (R) were compared. Timeliness of care was also measured.
Results: No MRI scan pauses were found in 92% and 80% in the GAS and GAP groups. The median and interquartile A scores were 3 (0, 7) in GAS and 0 (0, 4) in GAP groups respectively. There was no difference in respiratory complications between GAS and GAP ( P = 0.62). The median and interquartile postanesthesia care unit (PACU) times were 25 (18, 34) for GAS and 31 (25, 44) for GAP ( P = 0.0001). The median and interquartile total times were 78 (69, 90) for GAS and 88 (78, 100) for GAP ( P = 0.0002).
Conclusion: Our study compared the three primary outcomes of pausing, agitation, and respiratory complications between the two groups, and we found no difference in respiratory complications. However, the GAP group had more pausing and less agitation than the GAS group. 相似文献
Aim: To measure and compare the quality between sevoflurane and propofol in children undergoing MRI scans.
Background: No randomized controlled trial exists comparing the quality between sevoflurane and propofol for MRI.
Methods/Materials: Two hundred unpremedicated children (18 months to 7 years) scheduled for brain MRI scans were recruited. After induction with sevoflurane, children were randomized to receive sevoflurane [general anesthesia with sevoflurane (GAS)] via laryngeal mask airway (LMA) or propofol [general anesthesia with propofol (GAP)] bolus and infusion for their scan. The three primary outcomes of pausing the MRI scan (P), agitation (A), and respiratory complications (R) were compared. Timeliness of care was also measured.
Results: No MRI scan pauses were found in 92% and 80% in the GAS and GAP groups. The median and interquartile A scores were 3 (0, 7) in GAS and 0 (0, 4) in GAP groups respectively. There was no difference in respiratory complications between GAS and GAP ( P = 0.62). The median and interquartile postanesthesia care unit (PACU) times were 25 (18, 34) for GAS and 31 (25, 44) for GAP ( P = 0.0001). The median and interquartile total times were 78 (69, 90) for GAS and 88 (78, 100) for GAP ( P = 0.0002).
Conclusion: Our study compared the three primary outcomes of pausing, agitation, and respiratory complications between the two groups, and we found no difference in respiratory complications. However, the GAP group had more pausing and less agitation than the GAS group. 相似文献
37.
MATTHIAS W. KÖNIG MD † ANNA M. VARUGHESE MD MPH † KATHLEEN A. BRENNEN CRNA SEAN BARCLAY CRNA T. MICHAEL SHACKLEFORD DO † PAUL J. SAMUELS MD † KRISTIN GORMAN BS JILLIAN ELLIS BA YU WANG MS ‡ TODD G. NICK PHD †‡ 《Paediatric anaesthesia》2009,19(8):748-755
Background: Pediatric dental procedures are increasingly performed under general anesthesia because of the inability to cooperate, situational anxiety, or other behavioral problems. Volatile anesthetics have been associated with emergence delirium in children, whereas the use of propofol for anesthetic maintenance has been shown to reduce the incidence of emergence delirium after other types of surgeries. The aim of this study is to compare a sevoflurane-based anesthetic with a propofol-based technique as it relates to the incidence of emergence delirium and the quality of recovery after pediatric dental surgery, in patients who present with risk factors for perioperative behavioral issues.
Methods: We prospectively collected data of 179 pediatric patients scheduled for ambulatory dental surgery using a double-blind and randomized trial design. Subjects were anesthetized following standardized protocols for either a sevoflurane- or a propofol-based technique. The incidence of emergency delirium, as measured by the Pediatric Anesthesia Emergence Delirium score, was the primary outcome. Secondary outcomes included the incidence of postoperative nausea and vomiting (PONV), number of nursing interventions in the recovery room, time to discharge readiness, and parental satisfaction.
Results: We found no difference in the incidence of emergence delirium after both types of anesthesia. However, use of sevoflurane significantly increased both the risk of PONV and the number of postoperative nursing interventions. Discharge criteria were met about 10 min earlier in patients anesthetized with sevoflurane. Parental satisfaction was equally high with both anesthesia regimens.
Conclusions: A propofol-based anesthetic technique did not lead to a lower incidence of emergence delirium after dental surgery in children but did result in significantly less PONV and fewer postoperative nursing interventions. 相似文献
Methods: We prospectively collected data of 179 pediatric patients scheduled for ambulatory dental surgery using a double-blind and randomized trial design. Subjects were anesthetized following standardized protocols for either a sevoflurane- or a propofol-based technique. The incidence of emergency delirium, as measured by the Pediatric Anesthesia Emergence Delirium score, was the primary outcome. Secondary outcomes included the incidence of postoperative nausea and vomiting (PONV), number of nursing interventions in the recovery room, time to discharge readiness, and parental satisfaction.
Results: We found no difference in the incidence of emergence delirium after both types of anesthesia. However, use of sevoflurane significantly increased both the risk of PONV and the number of postoperative nursing interventions. Discharge criteria were met about 10 min earlier in patients anesthetized with sevoflurane. Parental satisfaction was equally high with both anesthesia regimens.
Conclusions: A propofol-based anesthetic technique did not lead to a lower incidence of emergence delirium after dental surgery in children but did result in significantly less PONV and fewer postoperative nursing interventions. 相似文献
38.
NARASIMHAN JAGANNATHAN MD LISA SOHN MD AMOD SAWARDEKAR MD REW AMBROSY BS JENNIFER HAGERTY DO † ANTHONY CHIN MD ‡ KATHLEEN BARSNESS MD ‡ SANTHANAM SURESH MD 《Paediatric anaesthesia》2009,19(9):892-898
Background: Inguinal hernia repair, hydrocelectomy, and orchidopexy are commonly performed surgical procedures in children. Postoperative pain control is usually provided with a single‐shot caudal block. Blockade of the ilioinguinal nerve may lead to additional analgesia. The aim of this double‐blind, randomized controlled trial was to evaluate the efficacy of an adjuvant blockade of the ilioinguinal nerve using ultrasound (US) guidance at the end of the procedure with local anesthetic vs normal saline and to explore the potential for prolongation of analgesia with decreased need for postoperative pain medication. Methods: Fifty children ages 1–6 years scheduled for unilateral inguinal hernia repair, hydrocelectomy, orchidopexy, or orchiectomy were prospectively randomized into one of two groups: Group S that received an US‐guided ilioinguinal nerve block with 0.1 ml·kg?1 of preservative‐free normal saline and Group B that received an US‐guided nerve block with 0.1 ml·kg?1 of 0.25% bupivacaine with 1 : 200 000 epinephrine at the conclusion of the surgery. After induction of anesthesia but prior to surgical incision, all patients received caudal anesthesia with 0.7 ml·kg?1 of 0.125% bupivacaine with 1 : 200 000 epinephrine. Patients were observed by a blinded observer for (i) pain scores using the Children and Infants Postoperative Pain Scale, (ii) need for rescue medication in the PACU, (iii) need for oral pain medications given by the parents at home. Results: Forty‐eight patients, consisting of 46 males and two females, with a mean age of 3.98 (sd ± 1.88) were enrolled in the study. Two patients were excluded from the study because of study protocol violation and/or alteration in surgical procedure. The average pain scores reported for the entire duration spent in the recovery room for the caudal and caudal/ilioinguinal block groups were 1.92 (sd ± 1.59) and 1.18 (sd ± 1.31), respectively. The average pain score difference was 0.72 (sd ± 0.58) and was statistically significant (P < 0.05). In addition, when examined by procedure type, it was found that the difference in the average pain scores between the caudal and caudal/ilioinguinal block groups was statistically significant for the inguinal hernia repair patients (P < 0.05) but not for the other groin surgery patients (P = 0.13). For all groin surgery patients, six of the 23 patients in the caudal group and eight of the 25 patients in the caudal/ilioinguinal block group required pain rescue medications throughout their entire hospital stay or at home (P = 0.76). Overall, the caudal group received an average of 0.54 (sd ± 1.14) pain rescue medication doses, while the caudal/ilioinguinal block group received an average of 0.77 (sd ± 1.70) pain rescue medication doses; this was, however, not statistically significant (P = 0.58). Conclusions: The addition of an US‐guided ilioinguinal nerve block to a single‐shot caudal block decreases the severity of pain experienced by pediatric groin surgery patients. The decrease in pain scores were particularly pronounced in inguinal hernia repair patients. 相似文献
39.
Samir R. Kapadia MD FACC Sachin S. Goel MD Lars Svensson MD PhD Eric Roselli MD Robert M. Savage MD Lee Wallace MD Srikanth Sola MD FACC Paul Schoenhagen MD FACC Mehdi H. Shishehbor DO MPH Ryan Christofferson MD Carmel Halley MD L. Leonardo Rodriguez MD FACC William Stewart MD FACC Vidyasagar Kalahasti MD FACC E. Murat Tuzcu MD FACC 《The Journal of thoracic and cardiovascular surgery》2009,(6):1430-1435
40.
Hanover TM Kalbaugh CA Gray BH Langan EM Taylor SM Androes MP Jones WT Blackhurst DW 《Annals of vascular surgery》2005,19(6):817-822
We evaluated both the safety and efficacy of reteplase for treatment of acute arterial occlusion as well as outcomes based on treatment of the underlying lesion. From November 2000 to February 2004, reteplase was used to treat arterial occlusions in 81 patients. Catheter-directed intrathrombus thrombolysis was performed with reteplase (0.5 units/hr) continuous infusion. Percutaneous mechanical thrombectomy (Angiojet) was performed in 61% (n = 50) of patients prior to thrombolysis. Unmasking of significant lesions resulted in endovascular intervention (39.5%), open surgical repair (24.6%), or both endovascular and surgical repair (9.8%) of the lesion. No lesion was found in 25.9% of patients. Major and minor complication rates as well as restoration of patency, limb salvage, and amputation-free survival were evaluated. Eighty-one patients received reteplase therapy (median = 10.3 +/- 5.3 units, 19.5 +/- 7.4 hr) followed by next-day arteriogram to assess thrombus removal. Technical success was achieved in 96.2% (n = 78) of cases. Kaplan-Meier life table analysis revealed overall primary patency rates of 76.3%, 60.1%, and 51.6%, at 1, 6, and 12 months, respectively. Overall amputation-free survival rates were 86.4%, 76.4%, and 69.7% at 1, 6, and 12 months, respectively. When subdivided into postlysis intervention, the lysis-only group achieved increased patency (p = 0.0143) and increased limb salvage (p = 0.0219) at 1 year compared to the lysis and endovascular intervention and the lysis and surgical groups. The 30-day complication rate was 17.3% (n = 14), with a major complication rate of 4.9% (n = 4) and a minor complication rate of 12.3% (n = 10). There were no intracranial hemorrhagic complications. Intra-arterial catheter-directed infusion of reteplase for acute lower extremity ischemia is safe and efficacious, as shown by the low risk of bleeding complications, high limb salvage rates, and low mortality rates in this study. The complexity of the lesion that is unmasked through thrombolytic therapy is a predictor of patency and limb salvage. 相似文献