首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9388篇
  免费   490篇
  国内免费   53篇
医药卫生   9931篇
  2024年   4篇
  2023年   85篇
  2022年   113篇
  2021年   357篇
  2020年   216篇
  2019年   259篇
  2018年   370篇
  2017年   246篇
  2016年   255篇
  2015年   374篇
  2014年   460篇
  2013年   520篇
  2012年   857篇
  2011年   968篇
  2010年   467篇
  2009年   397篇
  2008年   698篇
  2007年   697篇
  2006年   591篇
  2005年   495篇
  2004年   461篇
  2003年   384篇
  2002年   338篇
  2001年   32篇
  2000年   24篇
  1999年   33篇
  1998年   39篇
  1997年   22篇
  1996年   20篇
  1995年   7篇
  1994年   15篇
  1993年   13篇
  1992年   9篇
  1991年   9篇
  1989年   7篇
  1988年   11篇
  1987年   4篇
  1986年   3篇
  1985年   5篇
  1984年   5篇
  1983年   4篇
  1982年   5篇
  1981年   4篇
  1980年   7篇
  1978年   3篇
  1977年   3篇
  1975年   4篇
  1973年   4篇
  1965年   5篇
  1963年   3篇
排序方式: 共有9931条查询结果,搜索用时 20 毫秒
11.
L1 disease is the most common genetic cause of congenital hydrocephalus. Mutations in the L1CAM gene are associated with an overlapping clinical spectrum of four X-linked neurological conditions, characterized by hydrocephalus, mental retardation, lower limb spasticity and adducted thumbs. Brain anomalies are frequently present in L1 disease. We describe these anomalies by reporting a case of a male newborn presenting with congenital hydrocephalus along with corpus callosum agenesis and enlargement of the massa intermedia. These findings, in association with the presence of clasped thumbs, raised the suspicion of L1 disease, which was confirmed by the detection of a mutation in the L1CAM gene. In cases of congenital hydrocephalus, recognition of the brain anomalies associated with L1 disease may contribute to pursuing the genetic analysis needed for the diagnosis and genetic counseling.  相似文献   
12.
OBJECTIVE: The authors tested the effect of blood sampling (skin versus venous puncture) on some biochemical and hematological blood parameters in athletes to answer whether skin puncture could be used as a substitute for venous puncture. DESIGN: Comparative study of 2 methods of blood samples collection. SETTING: The blood was collected in the same athletes at 3 different moments of the preparatory training phase. PARTICIPANTS: Fourteen male indoor soccer players (22 +/- 1 years old) and 7 female handball players (18 +/- 1 years old) participated. MAIN OUTCOME MEASUREMENT: Blood was collected in heparin and K3EDTA by Vacutainer BD or Microvette Sarstedt system for biochemical and hematological analyses, respectively. RESULTS: There were no significant statistical differences between the 2 methods for the values of creatine kinase, urea, creatinine, lymphocytes, and platelets. The other hematological analyzes and uric acid exhibited significant higher values in skin blood, although they were all within the normal expected range. A high degree of correlation was observed between the 2 techniques for all parameters. CONCLUSIONS: Skin puncture is a reliable, easy, accurate, and less invasive sampling method for assessing hematological and some biochemical parameters in athletes, respecting that blood samples should always be obtained from the same site, especially in follow-up studies.  相似文献   
13.
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies.  相似文献   
14.
BACKGROUND: Randomized studies demonstrate that laparoscopic appendectomy yields better results compared with open techniques. We sought to identify factors that determine an extended hospital stay among patients undergoing laparoscopic appendectomy. METHODS: This was a prospective study including 669 patients undergoing laparoscopic appendectomy. We analyzed variables that can predict the length of hospital stay. RESULTS: Of 669 patients undergoing laparoscopic appendectomy, 141 stayed in the hospital for > or = 5 days (Group 1), and 97 stayed in the hospital for < or = 1 day after surgery (Group 2). The univariate analysis demonstrated that fever (P<0.0001), nausea and vomiting (P=0.060), leukocytosis (P<0.0001), gangrened or perforated intraoperative appearance of the appendix (P<0.0001), and appendix position behind the ileocecal junction (P<0.001) were related to a longer hospital stay. The multivariate analysis through logistical regression showed that the factors independently and significantly associated with an extended hospital stay were presurgical fever, appendix position behind the ileocecal junction, and intraoperative gangrened or perforated appearance of the appendix. CONCLUSION: Fever, appearance, and position of the appendix are factors related to an extended hospital stay.  相似文献   
15.
16.
We report the case of a 49-year-old patient, with recent onset of fatigue, who was diagnosed with atrial fibrillation, which was cardioverted electrically. A diagnosis of right atrial aneurysm, with no other cardiac pathology, was made. An aneurysmectomy was performed. Both surgery and postoperative recovery were uneventful.  相似文献   
17.
The Monte Carlo method was used to calculate the efficiency, escape and Compton curves of a planar high-purity germanium detector (HPGe) in the 20-150 keV energy. These curves were used for the determination of photons spectra produced by an X-ray machine in order to allow a precise characterization of photon beams applied to medical diagnosis. The detector was modeled with the MCNP5 computer code and validated by comparison with experimental data. The air kerma calculated after the spectra stripping was compared with ionization chamber measurements.  相似文献   
18.
Asthma patients that depend on emergency department (ED) services are generally considered to have extremely poor disease control and prognosis. It is important to identify characteristics related to poor disease control and frequent visits to the ED to apply appropriate clinical management. This study comprised a cross-sectional survey of consecutive patients with asthma exacerbation (age ≥12 years) presenting at the adult ED of a large, tertiary care, university-affiliated hospital over a 2-month period. The frequent visitors (FV) were defined by ≥3 visits to the ED in the preceding year, and the occasional visitors (OV) by ≤2 visits. Eighty-six patients (61 females and 25 males) were included in the study (mean age 38 ± 18 years). Of these patients, 51.2% were FV and 48.8% were OV. Sixty-nine percent had annual income lower than A$3000 and 66.3% had ≤8 years of the formal education. Only 18.6% had used inhaled corticosteroids, 79.1% identified the asthma attack severity, 70.9% increased or initiated inhaled β-agonist, 20.9% increased or initiated steroid therapy, and 55.8% had an asthma action plan for attack. The number of hospital admissions in past year (OR 4.3, P = .02), use of home nebulizer (OR 3.6, P = .05) and the lack of a written asthma action plan (OR 3.3, P = .03) were independently associated with frequent visits to the ED. We conclude that a substantial proportion of the patients that visit the ED are FV. These patients are more likely to have hospital admission in the past year, to use a home nebulizer, and to lack a written asthma action plan. They should be considered the most important target for asthma education.  相似文献   
19.
Background Sympathectomy is the treatment of choice for primary hyperhidrosis. One curious occurrence that is difficult to explain from an anatomophysiological point of view in cases of video-assisted thoracoscopic sympathectomy (VATS) for the treatment of palmar hyperhidrosis (PH) is the observed improvement in plantar hyperhidrosis (PLH). Nevertheless, current reports on VATS rarely describe the effect on PLH or just give superficial data. The aim of this study was to prospectively investigate, how surgery affects PLH in patients with PH and PLH over one-year period. Methods From May 2003 to January 2004, 70 consecutive patients with combined PH and PLH underwent VATS at the T2, T3, or T4 ganglion level (47 women and 23 men, with mean age of 23 years). Results Immediately after the operation, all the patients said they were free from PH episodes, except for two patients (2.8%) who suffered from continued PH. Compensatory hyperhidrosis (CH) of various degrees was observed in 58 (90.6%) patients after one year. Only 13 (20.3%) suffered from severe CH. There was a great initial improvement in PLH in 50% of the cases, followed by progressive regression, such that only 23.4% still presented that improvement after one year. The number of cases without overall improvement increased progressively (from 17.1% to 37.5%) and the numbers with slight improvement remained stable (32.9–39.1%). Of the 24 patients with no improvement after one year, 6 patients graded plantar sweating worse. Conclusion Patients with PH and PLH who undergo VATS to treat their PH present a good initial improvement in PLH that reduces to a lower level of improvement after the one-year period.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号