全文获取类型
收费全文 | 2598篇 |
免费 | 190篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 60篇 |
妇产科学 | 44篇 |
基础医学 | 293篇 |
口腔科学 | 67篇 |
临床医学 | 201篇 |
内科学 | 541篇 |
皮肤病学 | 117篇 |
神经病学 | 106篇 |
特种医学 | 156篇 |
外科学 | 470篇 |
综合类 | 69篇 |
预防医学 | 128篇 |
眼科学 | 96篇 |
药学 | 140篇 |
中国医学 | 12篇 |
肿瘤学 | 222篇 |
出版年
2023年 | 22篇 |
2022年 | 56篇 |
2021年 | 119篇 |
2020年 | 55篇 |
2019年 | 62篇 |
2018年 | 82篇 |
2017年 | 63篇 |
2016年 | 73篇 |
2015年 | 55篇 |
2014年 | 91篇 |
2013年 | 135篇 |
2012年 | 192篇 |
2011年 | 184篇 |
2010年 | 123篇 |
2009年 | 79篇 |
2008年 | 152篇 |
2007年 | 165篇 |
2006年 | 159篇 |
2005年 | 151篇 |
2004年 | 139篇 |
2003年 | 91篇 |
2002年 | 84篇 |
2001年 | 48篇 |
2000年 | 35篇 |
1999年 | 20篇 |
1998年 | 19篇 |
1997年 | 10篇 |
1996年 | 20篇 |
1995年 | 19篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 29篇 |
1991年 | 23篇 |
1990年 | 17篇 |
1989年 | 23篇 |
1988年 | 19篇 |
1987年 | 13篇 |
1986年 | 11篇 |
1985年 | 18篇 |
1984年 | 19篇 |
1983年 | 13篇 |
1982年 | 10篇 |
1981年 | 5篇 |
1980年 | 10篇 |
1979年 | 13篇 |
1978年 | 6篇 |
1975年 | 4篇 |
1974年 | 6篇 |
1973年 | 6篇 |
1970年 | 6篇 |
排序方式: 共有2799条查询结果,搜索用时 15 毫秒
1.
Palat Balachandran M.S. M.Ch. Shaleen Agarwal M.S. M.Ch. Narendra Krishnani M.D. Chandra M. Pandey Ph.D. Ashok Kumar M.S. M.Ch. Sadiq S. Sikora M.S. Rajan Saxena M.S. Vinay K. Kapoor M.S. 《Journal of gastrointestinal surgery》2006,10(6):848-854
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer.
A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple
cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival
<24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status
(P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was
seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year
survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival
in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive
disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated
with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in
patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III
and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in
gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival
in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival. 相似文献
2.
National Programme of Research in Human Reproduction S.K. Banerjee R. Baveja R.V. Bhatt A. Chatterjee S.D. Choudhury B. Coyaji A.D. Engineer M.P. Gogoi V. Hingorani K. Lal M. Kochhar U. Krishna P. Misra F.S. Philips R. Rajan P.C. Sen Gupta K. Zaveri S. Datey S. Gupta S. Mehta N.C. Saxena B.N. Saxena 《Contraception》1986,34(6):573-582
The return of fertility following discontinuation of norethisterone oenanthate (NET EN) 200 mg injectable contraceptive after use for a minimum period of six months or more was studied in 69 women who discontinued the method for planning pregnancy. Former users of copper intra-uterine device (CuT 200) were enrolled as a control group. Another 161 women who had discontinued NET EN due to other reasons (e.g. amenorrhoea, excessive bleeding or personal reasons) were also studied for return of fertility after ensuring that they were not using any other method of contraception and were exposed to the risk of pregnancy. The subjects from both groups were followed for a period of one year. The cumulative conception rates at one year were 72.5 and 83.6 per 100 subjects for ex-NET EN and ex-CuT 200 users who had discontinued the method for planning pregnancy and this difference was not statistically significant (P > 0.05). The median time for conception for ex-NET EN users was 7.8 months as compared to 3.7 months in ex-CuT 200 users but the cumulative conception rates at the end of one year show that future return of fertility in NET EN users does not appear to be adversely affected.
In 51 subjects who had discontinued NET EN due to amenorrhoea, the return of fertility was predictably slower and less. The return of fertility in subjects who discontinued NET EN for other reasons (e.g. excessive bleeding and other personal reasons) was similar to ex-NET EN and ex-CuT 200 users. 相似文献
3.
Brca2 is coordinately regulated
with Brca1 during proliferation and
differentiation in mammary epithelial cells
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
JayantV. Rajan Man Wang SandraT. Marquis LewisA. Chodosh 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(23):13078-13083
We have analyzed the expression of the breast cancer susceptibility gene, Brca2, in mammary epithelial cells as a function of proliferation and differentiation. Our results demonstrate that Brca2 mRNA expression is tightly regulated during mammary epithelial proliferation and differentiation, and that this regulation occurs coordinately with Brca1. Specifically, Brca2 mRNA expression is up-regulated in rapidly proliferating cells; is down-regulated in response to serum deprivation; is expressed in a cell cycle-dependent manner, peaking at the G1/S boundary; and is up-regulated in differentiating mammary epithelial cells in response to glucocorticoids. In each case, an identical pattern of expression was observed for Brca1. These results indicate that proliferative stimuli modulate the mRNA expression of these two breast cancer susceptibility genes. In addition, the coordinate regulation of Brca1 and Brca2 revealed by these experiments suggests that these genes are induced by, and may function in, overlapping regulatory pathways involved in the control of cell proliferation and differentiation. 相似文献
4.
The effects of localized gamma-irradiation on the in vivo 31P NMR spectra of RIF-1 tumors grown subcutaneously in C3H/HeN mice have been examined before and during the week after treatment. Increases in the ratio of phosphocreatine (PCr) to inorganic phosphate (Pi) and in tumor pH, and decreases in the ratio of Pi to the beta phosphorus resonance of the nucleotide triphosphates (beta NTP) were observed in irradiated tumors. The time course of changes in the 31P spectrum following treatment was the opposite of the pattern during untreated growth, and the magnitude and duration of the changes increased with increasing radiation dose, decreasing clonogenic cell survival and increasing growth delay. To examine the possibility that nontherapeutic systemic effects of the tumor irradiation were responsible for the changes observed, a number of animals bearing two tumors were examined. One tumor on each mouse was selectively irradiated. Changes in tumor volume, Pi/beta NTP, PCr/Pi, the ratio of phosphomonoesters to beta NTP, and tumor pH were all significantly different in the treated compared to the untreated tumor on each animal, indicating that these changes in 31P NMR spectra were a response to radiation therapy and not a systemic response to radiation toxicity. 相似文献
5.
6.
Marie-France Juneau Rajan RN BScN CCRN MScN 《Journal of advanced nursing》1995,22(3):450-455
Transcultural nursing care is a well-established theoretical framework. This theory, developed by Madeleine Leininger, can have an impact on clinical practice, academic preparation and nursing research. The heightened interest in applying transcultural care and the increased need to espouse this framework have been triggered by constant population changes. This paper defines transcultural nursing care and expands its definition further by comparing and contrasting it with Jean-Paul Sartre's existentialist perspective. The two modes of existence as defined by Sartre are closely examined. Concrete examples are offered as cultural phenomena and the components of a cultural assessment are discussed and applied. The philosophical thesis is approached from a transcultural nursing perspective and existentialism is shown to serve as a foundation for transcultural nursing. The advantages and disadvantages of transcultural nursing practice and the preparation of transcultural nurses are finally addressed. 相似文献
7.
8.
Hepatitis B infection in prostitutes 总被引:1,自引:0,他引:1
The prevalence of HBV markers in prostitutes is known to be higher than that of the normal population of similar age range in previous studies. This study showed a significant correlation between the duration of prostitution and the prevalence of HBV antibodies amongst the prostitutes. The prevalence of HBV antibodies doubled after the first year of prostitution. A two-year follow-up study of these prostitutes showed that 37% of HBsAg positive prostitutes lost the HBsAg. The seroconversion rate of HBsAg negative prostitutes was 10% during this two-year period. Early immunization against HBV infection should be considered in this high risk group in view of these findings. 相似文献
9.
Ambakumar Nandakumar Narayanappa Anantha Thalagavadi Venugopal Sreerama Reddy Bapsy Padmanabhan Kumara Swamy Dinesh Doval Clementina Ramarao 《International journal of cancer. Journal international du cancer》1995,63(1):37-42
Lymphoid and haemopoietic malignancies as a group constitute one of the important cancers in India, as elsewhere in the world. While information on incidence and mortality of these cancers, and that on survival, are available from most developed countries, there are very few reports describing this experience in developing ones. Population-based cancer registration commenced in Bangalore, India, in January 1982, under the auspices of the Indian Council of Medical Research. This source provides fairly complete and reliable incidence data, but, in order to obtain mortality and survival information, active follow-up involving visits of homes of patients was undertaken. Between 1982 and 1989, 1397 cases of lymphoid and haemopoietic malignancies were registered in the Bangalore cancer registry, giving an age-adjusted incidence rate of 7.7 and 4.8 per 100,000 in males and females respectively. Active follow-up provided mortality/survival information in 1267 or 90.7% of these cases. The overall observed 5-year survival for these cancers combined (both sexes) was 26%, and relative survival 28.4%. The 5-year survival rate was lower in all the individual lymphomas and leukaemias as compared with similar reports from the developed countries. Survival in Hodgkin's disease was influenced by clinical stage and age at presentation. 相似文献
10.
Nadim Aslam Stephen Gwilym Christos Apostolou Nicholas Birch Rajan Natarajan William Ribbans 《European journal of emergency medicine》2004,11(3):148-150
OBJECTIVES: To illustrate the types of injuries seen by the accident and emergency department as a result of the use of non-motorized 'microscooters' in children, and to increase awareness of scooter-related triplane fractures of the ankle. STUDY DESIGN: A retrospective study conducted in an accident and emergency department of a district general hospital on all children who had a scooter-related limb injury over a 6-month period and were referred for orthopaedic review. METHODS: The analysis involved a case note review. Information recorded included the injury sustained, protective equipment worn at the time of the accident and management by the orthopaedic team. RESULTS: Scooter injuries accounted for 10 fractures in this period. There were three 'triplanar' injuries, which required operative fixation, and three injuries requiring manipulation under anaesthesia. No protective gear was worn by any of the patients. CONCLUSION: The popularity of microscooters seems to represent a significant risk of bony injury in the paediatric population. Medical personnel who manage acute paediatric trauma should be aware of scooter-related triplanar ankle injuries. 相似文献