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   295篇
  免费   0篇
综合类   1篇
化学工业   2篇
轻工业   7篇
冶金工业   285篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2018年   1篇
  2015年   1篇
  2014年   2篇
  2013年   1篇
  2003年   1篇
  1999年   5篇
  1998年   76篇
  1997年   56篇
  1996年   25篇
  1995年   15篇
  1994年   15篇
  1993年   24篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1986年   1篇
  1982年   3篇
  1981年   1篇
  1980年   6篇
  1978年   2篇
  1977年   15篇
  1976年   37篇
排序方式: 共有295条查询结果,搜索用时 15 毫秒
111.
112.
STUDY OBJECTIVE: The aim was to study the spectrum of clinical problems and outcomes in infants born at an urban academic hospital. In consequence, as part of the overall study, the incidence of congenital anomalies and the outcomes of affected infants were recorded. DESIGN: This was a prospective, hospital-based study, undertaken on liveborn infants born over a 3-year period, 1 May 1986 to 30 April 1989. SETTING: Kalafong Hospital, Pretoria. MAIN RESULTS: A total of 17,351 liveborn infants was examined and the total congenital anomalies incidence was 11.87 per 1,000 livebirths. The central nervous system was the system most frequently involved (2.30 per 1,000 livebirths), followed by the musculoskeletal system (2.13 per 1,000 livebirths). The commonest individual congenital anomaly was Down syndrome (1.33 per 1,000 livebirths), followed by neural tube defects (0.99 per 1,000 livebirths) and ventricular septal defects (0.69 per 1,000 livebirths). In 11% (2.25 per 1,000 livebirths) of neonatal deaths, infant loss was attributable to congenital anomalies. CONCLUSIONS: The incidence of congenital anomalies in black South African neonates, born in an urban setting, is as high as in other First- and Third-World countries, and the incidence of some individual congenital anomalies is higher. This study indicates the need for further research and the establishment of prenatal, genetics and paediatric facilities to manage these problems.  相似文献   
113.
114.
115.
DNA amplification at 20q13.2 is common in breast cancer, correlates with poor prognosis, and may reflect location of an important oncogene. Recently, other regions along 20q were also found to undergo amplification. Here, amplification levels and patterns of co-amplification were analyzed by interphase fluorescence in situ hybridization at 14 loci along 20q in 146 uncultured breast carcinomas and 14 cell lines. Three regions were independently amplified in uncultured tumors: RMC20C001 region at 20q13.2 (highly amplified in 9.6% of the cases), PTPN1 region 3 Mb proximal (6.2%), and AIB3 region at 20q11 (6.2%). Co-amplifications involving two or three of these regions were seen in 11 of the 19 highly amplified tumors. The results suggest that three distinct nonsyntenic regions along 20q may be important and that complex chromosomal rearrangements underlie their frequent co-amplification in breast cancer.  相似文献   
116.
117.
A patient with rheumatoid arthritis (RA) developed an infection caused by Listeria monocytogenes in her left knee and both shoulder joints. The clinical presentation of the disease was rather indolent with relatively moderate joint symptoms. Moreover, the synovial fluid sample was only slightly turbid with a white blood cell count of 23.5 x 10(9)/1. As compared to the earlier reported cases of L. monocytogenes septic arthritis, our patient is unique because she had infection in several joints. The polyarticular joint involvement combined with the clinical symptoms resembling the activation of RA posed us diagnostic difficulties.  相似文献   
118.
The National Family Planning Board is the agency of Government empowered to prepare, carry out and promote family planning programs in Jamaica. The Board has prioritized the expansion and sustainability of family planning services in large part through encouraging the participation of the private sector. To enhance the availability, acceptability and effectiveness of private physician family planning services, information was collected on the service practices of 90% of physicians, through face to face interviews. Bruce's framework was used to evaluate the findings of the study. The study indicated that: A wide variety of contraceptives are available - Basic equipment and adequate supplies are in place for the provision of services - Provider bias, inappropriate contraindicators and process and scheduling hurdles exist. The major recommendations relate to the: Revision of norms and guidelines for all contraceptives - Continuation of contraceptive technology updates for private physicians - Revision of legal/regulatory barriers which restrict access to some contraceptives for certain target groups.  相似文献   
119.
120.
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