全文获取类型
收费全文 | 50924篇 |
免费 | 5499篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 356篇 |
儿科学 | 1498篇 |
妇产科学 | 1009篇 |
基础医学 | 7129篇 |
口腔科学 | 1443篇 |
临床医学 | 6165篇 |
内科学 | 9999篇 |
皮肤病学 | 745篇 |
神经病学 | 4353篇 |
特种医学 | 1920篇 |
外国民族医学 | 1篇 |
外科学 | 6684篇 |
综合类 | 1223篇 |
一般理论 | 40篇 |
预防医学 | 5874篇 |
眼科学 | 978篇 |
药学 | 4351篇 |
中国医学 | 95篇 |
肿瘤学 | 2640篇 |
出版年
2021年 | 713篇 |
2020年 | 446篇 |
2019年 | 742篇 |
2018年 | 873篇 |
2017年 | 624篇 |
2016年 | 707篇 |
2015年 | 855篇 |
2014年 | 1161篇 |
2013年 | 1678篇 |
2012年 | 2417篇 |
2011年 | 2460篇 |
2010年 | 1381篇 |
2009年 | 1355篇 |
2008年 | 2305篇 |
2007年 | 2433篇 |
2006年 | 2384篇 |
2005年 | 2316篇 |
2004年 | 2157篇 |
2003年 | 2038篇 |
2002年 | 2002篇 |
2001年 | 1601篇 |
2000年 | 1509篇 |
1999年 | 1530篇 |
1998年 | 661篇 |
1997年 | 518篇 |
1996年 | 515篇 |
1995年 | 525篇 |
1994年 | 452篇 |
1993年 | 509篇 |
1992年 | 1231篇 |
1991年 | 1148篇 |
1990年 | 1092篇 |
1989年 | 1060篇 |
1988年 | 987篇 |
1987年 | 973篇 |
1986年 | 994篇 |
1985年 | 910篇 |
1984年 | 793篇 |
1983年 | 659篇 |
1982年 | 447篇 |
1981年 | 377篇 |
1980年 | 354篇 |
1979年 | 599篇 |
1978年 | 495篇 |
1977年 | 376篇 |
1976年 | 385篇 |
1974年 | 434篇 |
1973年 | 403篇 |
1972年 | 389篇 |
1969年 | 358篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Francisco M. Averhoff Walter W. Williams Stephen C. Hadler 《The Journal of school health》1997,67(7):298-303
SUMMARY: This report concerning the immunization of adolescents (ie, persons 11–21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (ie, MMWR 1994;43[No. RR-1] 1–38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians [AAFP]; and AMA Guidelines for Adolescent Preventive Services [GAPS]: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11–12 years of age by establishing a routine visit to their health-care providers. Specifically, the purposes of this visit are to a) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps, and rubella (MMR) vaccine; b) provide a booster dose of tetanus and diphtheria toxoids; c) administer other vaccines that may be recommended for certain adolescents; and d) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine. The most recent recommendations from AC1P, AAP, AAFP, and AMA concerning specific vaccines and delivery of preventive services should be consulted for details. 相似文献
102.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
103.
104.
D I Williams 《Journal of the Royal Society of Medicine》1994,87(12):777-780
105.
The theoretical model for perfusion measurement by NMR using arterial labeling of endogenous water is extended to include the effects of transit time and cross-relaxation of tissue water with macromolecules. Water magnetization in rat brain is monitored using the STEAM method to simultaneously determine the transit time, magnetization transfer rate constant, and perfusion. The results show that the transit time in rat brain is quite short, and thus its effect on perfusion measurement is small. It is also demonstrated both theoretically and experimentally that the steady-state effects of cross-relaxation with macromolecules on perfusion measurement are accounted for by a proper control experiment. 相似文献
106.
E R Broun C R Nichols G Tricot P J Loehrer S D Williams L H Einhorn 《Bone marrow transplantation》1991,7(1):53-56
We report seven patients with germ cell tumors which either recurred following a minimum of two regimens of platinum-based chemotherapy or were refractory to cisplatin. The patients were treated with one or two courses of high dose carboplatin (CBDCA) and etoposide (VP-16) plus ifosfamide (IFX) with mesna uroprotection and autologous bone marrow support. The doses given were CBDCA 500 mg/m2 every other day x 3 and VP-16 400 mg/m2 every other day x 3. IFX was given in a dose of 2 g/m2 daily x 5 days with mesna. The original intent of the protocol was to explore escalating doses of IFX, but excessive renal toxicity at the first dose level prevented escalation. Of the seven patients treated, four developed a marked decline in their renal function and three of the four required hemodialysis or hemofiltration. Six of seven patients treated had a decline in their serum markers indicating a response to therapy, but all have relapsed. Our conclusion is that while the combination of CBDCA/VP-16/IFX with ABMT is active in this group of patients, it is associated with excessive renal toxicity which is probably due to underlying renal dysfunction secondary to extensive prior cisplatin-based chemotherapy. 相似文献
107.
Successful implementation of guidelines to prevent infective endocarditis (IE) depends upon the dental practitioner being aware of which of his patients are at risk. This was studied by sending a questionnaire to at risk patients and their dentists in the Grampian area. Of 145 respondents (53% response rate) with predisposing cardiac disorders, only 63 reported having seen their dentist in the past 2 years, although for dentate patients 47/61 had seen a dentist in the past 2 years. The dentists of 59 of these cases were then surveyed and replies received in 53 cases. Nineteen had no record of the patient having a cardiac disorder. In only 17 of the remaining cases was information on the cardiac disorder well enough recorded to warrant prophylaxis for at risk procedures. The dentist was usually told of the disorder only by the patient. Sixty-three per cent of dentists felt that communication between them and the patient's doctor was unsatisfactory. It is necessary to improve doctor/patient/dentist communication so that current recommendations on prophylaxis can be implemented to the full. This should be done through the patient's GP or consultant, who should communicate directly with the dentist. Details could also be inserted on warfarin cards and 'cardiac alert cards' expanded. 相似文献
108.
A case of an ovarian serous epithelial neoplasm of borderline type admixed with sarcomatous elements is reported. This combination seems to be extremely rare with only four cases previously reported. It may represent a type of collision tumour or the development of a sarcoma in a growth with borderline differentiation. 相似文献
109.
J-H. Longeville P. De La M. Hall P. Dolan A. W. Holt P. E. Lillie J. A. R. Williams R. T. A. Padbury 《HPB surgery》1997,10(3):159-162
We describe a case of giant cavernous haemangioma of the liver with disseminated intravascular coagulopathy (Kasabach-Merritt syndrome) which was cured by orthotopic liver transplant.A 47 year old man presented with bleeding and tender massive hepatomegaly after tooth extraction. Investigations showed disseminated intravascular coagulopathy and a giant hepatic haemangioma involving both lobes of the liver. Initial treatment failed to resolve the coagulopathy and liver resection was attempted. At laparotomy the turnout was unresectable and the only option for cure was to offer a liver transplantation. The orthotopic liver transplant was performed 20 days after initial laparotomy. Subsequently, all coagulation parameters returned to normal and the patient remains well after 12 months. Orthotopic liver transplant can be considered for giant hepatic haemangioma with Kasabach-Merritt syndrome when resection is necessary and a partial hepatectomy is not technically feasible. 相似文献
110.