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   324篇
  免费   23篇
  国内免费   1篇
儿科学   15篇
妇产科学   13篇
基础医学   55篇
口腔科学   9篇
临床医学   19篇
内科学   94篇
皮肤病学   5篇
神经病学   17篇
特种医学   4篇
外科学   30篇
综合类   5篇
预防医学   39篇
眼科学   4篇
药学   29篇
中国医学   1篇
肿瘤学   9篇
  2022年   4篇
  2021年   15篇
  2020年   3篇
  2019年   6篇
  2017年   3篇
  2016年   8篇
  2015年   9篇
  2014年   12篇
  2013年   16篇
  2012年   16篇
  2011年   21篇
  2010年   15篇
  2009年   6篇
  2008年   18篇
  2007年   14篇
  2006年   9篇
  2005年   18篇
  2004年   19篇
  2003年   13篇
  2002年   10篇
  2001年   5篇
  2000年   2篇
  1998年   3篇
  1997年   3篇
  1996年   2篇
  1995年   3篇
  1994年   2篇
  1992年   5篇
  1991年   7篇
  1990年   2篇
  1989年   4篇
  1985年   5篇
  1984年   7篇
  1983年   6篇
  1982年   5篇
  1981年   4篇
  1979年   2篇
  1978年   3篇
  1977年   8篇
  1976年   4篇
  1974年   5篇
  1972年   3篇
  1971年   3篇
  1969年   1篇
  1968年   4篇
  1967年   1篇
  1966年   2篇
  1965年   1篇
  1963年   1篇
  1945年   1篇
排序方式: 共有348条查询结果,搜索用时 15 毫秒
1.
We evaluated 50 mothers of children with Down syndrome attending Genetic Clinic of the Institute of Child Health and Hospital for Children, Madras, with special reference to their knowledge, belief and attitudes in the care of these children. After evaluation, they were educated individually and in groups with demonstration, picture cards and pamphlets, on the causation, expected health problems, developmental potential of Down syndrome and the ways and means to help the child to attain the maximum developmental potential. They were taught on preventive aspects of Down syndrome as well. Re-evaluation was done after three months, and considerable improvement was noted in the mother's knowledge, and attitude towards bringing up such a child. The mothers also showed an improvement in the skills in providing developmental enrichment to these children. Thus this study has formulated a programme in the management of such children, which can be practised on any population, anywhere, especially, in rural areas, and by less affluent folk, with poor educational background.  相似文献   
2.
From 1977 to 1988, 166 patients with median nerve paralysis of varied aetiology underwent opponensplasty. In 50 of these the extensor indicis was used, and in 116 the flexor digitorum superficialis of the ring finger. An analysis of these hands showed that the EI opponensplasty was best in supple hands and FDS opponensplasty was more suitable for less pliable hands. There were fewer complications seen after FDS opponensplasty if the detachment of the donor tendon was done through a volar oblique incision rather than the conventional lateral incision.  相似文献   
3.
A modified method of treatment of congenital absence of the vagina with the use of amnion graft has been explained with illustrations. Follow-up of 20 patients treated with this method showed successful results without any postoperative cicatrization provided the marital relationship was started within 6-8 weeks.  相似文献   
4.
Experimental mycetoma-like lesions developed in guinea pigs after subcutaneous injection of Nocardia asteroides. Although delayed hypersensitivity appeared earlier, increased macrophage migration inhibition and microbicidal activity appeared after 7 weeks. When the lesions healed, high cell-mediated immunity was present. Cell-mediated immunity was transferred to normal recipient guinea pigs from healed donor guinea pigs by spleen cell transfer. Recipient guinea pigs showed marked protection against challenge with N. asteroides.  相似文献   
5.
6.
A case of nonvenereal acquisition of syphilis in a 2.5 year old male Indian child is discussed. The child had condylomata lata around the anal and prepuce, with enlarged nontender inguinal lymph nodes. Treponema pallidum was found in material from both lesions, and both the VDRL and FTA-Abs tests were positive. There were not other significant findings. The patient was treated with 1.2 million units of benzathine penicillin im, and the lesions resolved in 7 days. This boy had been raised by his grandparents since the age of 6 months. They did not report a primary syphilitic lesion, but the grandmother did admit to kissing the child's genitals, a custom of affection toward babies in the area. Sexual abuse was denied. The grandmother had a buccal lesion, which showed a Treponema on darkfield microscopy, and she had positive syphilis serology. both grandparents were also treated.  相似文献   
7.
Introduction: During radiofrequency ablation to encircle or isolate the pulmonary veins (PVs), applications of radiofrequency energy within a PV may result in stenosis. The aim of this study was to determine whether monitoring of real-time impedance facilitates detection of inadvertent catheter movement into a PV.
Methods and Results: In 30 consecutive patients (mean age 53 ± 11 years) who underwent a left atrial ablation procedure, the three-dimensional geometry of the left atrium, the PVs, and their ostia were reconstructed using an electroanatomic mapping system. The PV ostia were identified based on venography, changes in electrogram morphology, and manual and fluoroscopic feedback as the catheter was withdrawn from the PV into the left atrium. Real-time impedance was measured at the ostium, inside the PV at approximately 1 and 3 cm from the ostium, in the left atrial appendage, and at the posterior left atrial wall. There was an impedance gradient from the distal PV (127 ± 30 Ω) to the proximal PV (108 ± 15 Ω) to the ostium (98 ± 11 Ω) in each PV (P < 0.01). There was no significant impedance difference between the ostial and left atrial sites. During applications of radiofrequency energy, movement of the ablation catheter into a PV was accurately detected in 80% of the cases (20) when there was an abrupt increase of ≥4 Ω in real-time impedance.
Conclusion: There is a significant impedance gradient from the distal PV to the left atrium. Continuous monitoring of the real-time impedance facilitates detection of inadvertent catheter movement into a PV during applications of radiofrequency energy. (J Cardiovasc Electrophysiol, Vol. 15, pp. 1-5, June 2004)  相似文献   
8.
Circannual and circadian variations in plasma levels of steroids were estimated by radioimmunoassay in the female and male catfish, Heteropneustes fossilis, over two consecutive annual reproductive cycles. In the female catfish, testosterone (T), estradiol-17β (E2), and estrone (E1) were detectable in the plasma only during the reproductively active (preparatory through spawning) period and their levels increased during vitellogenesis. In the fully gravid catfish, when vitellogenesis was nearly complete, levels of E2 declined but those of T continued to increase suggesting a product-precursor relationship between the two steroids. Plasma cortisol (F) was detectable throughout the year and exhibited three peaks coinciding with summer, monsoon, and winter; the first and second peaks coincided with vitellogenesis and spawning, respectively. In the male catfish, changes in plasma T and F levels closely paralleled the seasonal recrudescence and activity of testes and seminal vesicles. After spawning, gonads regressed and levels of sex steroids declined sharply. In the absence of natural spawning due to scanty monsoon rains, as during the second year of this study, gonadal regression was delayed and the sex steroids persisted in the plasma well beyond the normal spawning season. In addition, the first two peaks of F levels merged to form a plateau extending from the preparatory period until the late spawning period. The three sex steroids (T, E2, and E1) exhibited identical circadian rhythms; a major peak occurred at the onset of the dark phase (20:00 hr) and a minor peak was generally observed 4 hr after the onset of the light phase (12:00 hr). The amplitude of rhythms was greatest during the prespawning and the spawning periods. Cortisol peak levels generally alternated with those of sex steroids. Steroid rhythms show rather precise correlations with environmental factors such as photoperiod, temperature, and rainfall as well as with seasonal reproductive activity in both sexes of catfish.  相似文献   
9.
OBJECTIVES: We sought to determine whether elimination of pulmonary vein (PV) arrhythmogenicity is necessary for the efficacy of left atrial circumferential ablation (LACA) for atrial fibrillation (AF). BACKGROUND: The PVs often provide triggers or drivers of AF. It has been shown that LACA is more effective than PV isolation in eliminating paroxysmal AF. However, it is not clear whether complete PV isolation is necessary for the efficacy of LACA. METHODS: In 60 consecutive patients with paroxysmal (n = 39) or chronic (n = 21) AF (mean age 53 +/- 12 years), LACA to encircle the left- and right-sided PVs, with additional lines in the posterior left atrium and along the mitral isthmus, was performed under the guidance of an electroanatomic navigation system. The PVs were mapped with a decapolar ring catheter before and after LACA. If PV isolation was incomplete, no attempts at complete isolation were made. RESULTS: After LACA, there was incomplete electrical isolation of one or more PVs in 48 (80%) of the 60 patients. The prevalence of PV tachycardias was 82% before and 8% after LACA (p < 0.001). At 11 +/- 1 months of follow-up, 10 (83%) of the 12 patients with complete and 39 (81%) of 48 patients with incomplete PV isolation were free from recurrent AF without antiarrhythmic drug therapy (p = 1.0). A successful outcome was not related to the number of completely isolated PVs per patient (p = 0.6). CONCLUSIONS: Left atrial circumferential ablation modifies the arrhythmogenic substrate within the PVs. Complete electrical isolation of the PVs is not a requirement for a successful outcome after LACA.  相似文献   
10.
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