首页 | 本学科首页   官方微博 | 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   637篇
  免费   48篇
  国内免费   9篇
耳鼻咽喉   18篇
儿科学   72篇
妇产科学   39篇
基础医学   61篇
口腔科学   31篇
临床医学   57篇
内科学   82篇
皮肤病学   57篇
神经病学   38篇
特种医学   21篇
外科学   85篇
综合类   9篇
预防医学   9篇
眼科学   64篇
药学   33篇
中国医学   1篇
肿瘤学   17篇
  2023年   10篇
  2022年   15篇
  2021年   37篇
  2020年   19篇
  2019年   20篇
  2018年   30篇
  2017年   27篇
  2016年   36篇
  2015年   32篇
  2014年   32篇
  2013年   39篇
  2012年   39篇
  2011年   54篇
  2010年   16篇
  2009年   24篇
  2008年   33篇
  2007年   34篇
  2006年   46篇
  2005年   35篇
  2004年   42篇
  2003年   26篇
  2002年   21篇
  2001年   8篇
  2000年   3篇
  1999年   4篇
  1998年   4篇
  1997年   1篇
  1995年   2篇
  1994年   1篇
  1993年   1篇
  1992年   2篇
  1988年   1篇
排序方式: 共有694条查询结果,搜索用时 15 毫秒
51.
Nemaline myopathy is clinically and genetically heterogeneous. The most common autosomal recessive form affecting infants (NEM2) links to chromosome 2q, and is caused by mutations in the gene for nebulin. We have examined the immunocytochemical expression of nebulin in skeletal muscle in 11 cases of nemaline myopathy, from ten families, with linkage compatible to chromosome 2q.22, the locus for nebulin. Mutations in the gene for nebulin have been found in eight of these cases. Immunolabelling with polyclonal antibodies to C-terminal regions of nebulin was compared with antibodies to fibre-type-specific myofibrillar proteins, including myosin heavy chain isoforms and alpha-actinin isoforms. No cases showed a complete absence of C-terminal nebulin, and no enhancement of labelling of the rods was seen with conventional fluorescence microscopy. In control muscle an antibody to the M176-181 repeat region of nebulin showed higher expression in fibres with slow myosin, while ones to the serine-rich domain and to the SH3 domain showed uniform expression. In some cases of nemaline myopathy differences in these patterns were observed. Two siblings with a homozygous mutation in exon 185, that produces a stop codon, showed an absence of labelling only with the SH3 antibody, and other cases showed uneven labelling with this antibody or some fibres devoid of label. Fibre type correlations also showed differences from controls, as some fibres had a fast isoform of one protein but a slow isoform of another. These results indicate that analysis of nebulin expression may detect abnormalities in some cases linked to the corresponding locus and may help to direct molecular analysis. In addition, they may also be relevant to studies of fibre type plasticity and diversity in nemaline myopathy.  相似文献   
52.
OBJECTIVE: Investigation of the role of sleep states on the respiratory effort of controls and subjects with upper airway resistance syndrome (UARS) using nasal cannula/pressure transducer system and esophageal manometry. PATIENTS AND METHODS: One night's monitoring of sleep and breathing, including the determination of peak end inspiratory esophageal pressure (respiratory effort) with esophageal manometry and flow limitation with nasal cannula. Analysis of the data, breath-by-breath, using visual inspection and a computerized program. Setting - a university sleep laboratory. Patients were nine men with UARS and nine control men matched for age, ethnicity, and body mass index. RESULTS: A modulation of respiratory effort by sleep state and stages is seen in all subjects, the lowest noted during REM sleep and the highest associated with Slow Wave Sleep. When total nocturnal breaths are investigated, a significant difference between peak end inspiratory esophageal pressure [(Pes)-considered as an index of respiratory effort] is noted between normal subjects and UARS. Two specific breathing patterns, seen primarily in UARS patients, are NREM sleep stage dependent. Crescendos (defined as more negative peak end inspiratory Pes with each successive abnormal breath) occur mostly during stages 1-2 NREM sleep, while segments consisting of regular and continuous, breath-after-breath, high respiratory efforts are associated with Slow Wave Sleep. Depending on sleep stage, visually scored arousal response displays differences in Pes negativity. The termination of the abnormal breathing pattern, always well defined with Pes, is not necessarily associated with a pattern of 'flow limitation' at the nasal cannula tracing, even when a visually scored EEG arousal is present. CONCLUSIONS: UARS patients have significantly more breaths, with more negative peak end inspiratory Pes, than do control subjects. The modulation of peak end inspiratory Pes (an index of respiratory effort) by sleep stage and state differs in UARS patients and control subjects. The nasal cannula/pressure transducer system may not detect all abnormal breathing pattern during sleep. As indicated by the visual sleep scoring, repetitive arousals may lead to more or less severe sleep fragmentation.  相似文献   
53.
Lupus vulgaris is reinfection tuberculosis of the skin and may result from direct extension, or hematogenous or lymphatic spread from a tuberculosis focus. Lupus vulgaris following bacille Calmette-Guerin (BCG) vaccination is a rare entity. Incontinentia pigmenti is an X-linked dominant genodermatosis in which vesicular, verrucous, and pigmented lesions are associated with various developmental defects. There is evidence of altered immunologic reactivity in some patients with incontinentia pigmenti. A 12-year-old girl hospitalized for pulmonary tuberculosis presented with bizarre-shaped brown macules following Blaschko lines on the left deltoid area, compatible with incontinentia pigmenti, which had appeared following BCG vaccination at the age of 7 years. Histopathologic examination found noncaseated granulomas in the dermis. Antituberculous treatment for pulmonary and cutaneous tuberculosis was initiated along with genetic counseling. Immunologic abnormalities have been reported in conjunction with incontinentia pigmenti. Simultaneous occurrence of pulmonary and cutaneous tuberculosis in our patient might be either coincidental or indicate derangements in the cellular immune system.  相似文献   
54.
Background/aim Gastrointestinal (GI) system cancers are frequent among older adults and it is still difficult to predict which are at increased risk for postoperative complications. Frailty and sarcopenia are increasing problems of older population and may be associated with adverse outcomes. In this study we aimed to examine the effect of sarcopenia and frailty on postoperative complications in older patients undergoing surgery for GI cancers.Materials and methods Forty-nine patients admitted to general surgery clinic with the diagnosis of gastrointestinal system cancers were included in this cross-sectional study. Frailty status was assessed using the Edmonton Frail Scale (EFS). Sarcopenia was defined due to the EWGSOP2 criteria and ultrasonography was used to evaluate muscle mass.Results The median age of the patients was 70 (min-max: 65–87). Fourteen (28.6%) patients were found to be sarcopenic and 16 (32.7%) patients were frail, and 6 (37.5%) of these patients were also severe sarcopenic (p = 0.04). When the postoperative complications were assessed, time to oral intake, time to enough oral intake, length of hospital stay in the postoperative period were found to be longer in frail patients (p = 0.02, p = 0.03, p = 0.04 respectively). Postoperative complications were not different due to the sarcopenia.Conclusion Frailty, but not sarcopenia was associated with adverse outcomes in older adults undergoing GI cancer surgery. Comprehensive geriatric assessment before surgical intervention may help to identify patients who are at risk.  相似文献   
55.
Status of immune mediators in fibromyalgia   总被引:1,自引:0,他引:1  
Fibromyalgia (FM) is a form of nonarticular rheumatism characterized by long-term (> 3 months) and widespread musculoskeletal pain. However, the biophysiology of FM has remained elusive, and the treatment remains mainly empirical. There are numerous hypotheses about the pathophysiology of chronic widespread pain and FM; one includes a possible role of cytokines. Cytokines play a role in diverse clinical processes and phenomena such as fatigue, fever, sleep, pain, stress, and aching. Cytokines related to acute or repetitive tissue injuries may be responsible for long-term activation of spinal cord glia and dorsal horn neurons, thus resulting in central sensitization. Pain, stiffness, and depression in FM could be associated with some signs of inflammatory response system activation. Illumination of the pathophysiologic secrets of FM will result in more effective treatment regimens. We review the role of immune mediators in the pathophysiology of FM.  相似文献   
56.
Background The current study was designed to assess the effect of magnesium sulphate infusion on hemodynamic parameters, neuromuscular blocking, propofol consumption, serum concentration of magnesium ions, and recovery from anesthesia during total intravenous anesthesia. Methods For this study, 60 patients undergoing septorhinoplasty operations were randomly allocated to receive magnesium sulphate (group M) or saline (group C) intravenously. The patients in group M received 15% magnesium sulphate 50 mg/kg in 100 ml of saline, and those in group C received an equal volume of saline before induction of anesthesia followed by 8 mg/kg/h infusion of either magnesium sulphate (group M) or an equal volume of saline (group C) until the end of surgery. Anesthesia was induced and maintained with propofol, remifentanil infusions, and vecuronium in both groups. Results Propofol requirements were significantly lower in group M than in group C (p < 0.05). The hemodynamic variables were similar in the two groups. The neuromuscular potency of vecuronium was greater in group M than in group C (p < 0.05). The verbal numeric scale values for pain were found to be significantly lower in group M than in group C (p < 0.05). Whereas the serum magnesium was in the normal range at the induction of anesthesia in the both groups, it was significantly lower in group C than in group M postoperatively (p < 0.05). Conclusion Magnesium sulphate can be used safely as an adjuvant to total intravenous anesthesia for day case surgeries, with the effect from potentialization of neuromuscular blockade taken into consideration. Presented in part as an abstract at the Annual Congress of the Turkish Anaesthesiology and Reanimation Society, Antalya, Turkey, December 2005  相似文献   
57.
58.
59.
60.
Black tongue is a rare, benign, self‐limiting disorder caused by certain conditions and some medications. We report the first case of a child diagnosed with black tongue associated with ranitidine use. We report our case to emphasize the rare side effect of this frequently used drug. Health care professionals should be aware of the likelihood of ranitidine‐induced black tongue in clinical practice.  相似文献   
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