全文获取类型
收费全文 | 5855篇 |
免费 | 510篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 218篇 |
妇产科学 | 118篇 |
基础医学 | 778篇 |
口腔科学 | 132篇 |
临床医学 | 559篇 |
内科学 | 1157篇 |
皮肤病学 | 101篇 |
神经病学 | 359篇 |
特种医学 | 372篇 |
外科学 | 569篇 |
综合类 | 132篇 |
一般理论 | 4篇 |
预防医学 | 625篇 |
眼科学 | 162篇 |
药学 | 535篇 |
中国医学 | 71篇 |
肿瘤学 | 472篇 |
出版年
2023年 | 74篇 |
2022年 | 87篇 |
2021年 | 106篇 |
2020年 | 115篇 |
2019年 | 112篇 |
2018年 | 171篇 |
2017年 | 112篇 |
2016年 | 143篇 |
2015年 | 176篇 |
2014年 | 245篇 |
2013年 | 351篇 |
2012年 | 343篇 |
2011年 | 368篇 |
2010年 | 259篇 |
2009年 | 222篇 |
2008年 | 278篇 |
2007年 | 282篇 |
2006年 | 301篇 |
2005年 | 231篇 |
2004年 | 201篇 |
2003年 | 146篇 |
2002年 | 151篇 |
2001年 | 119篇 |
2000年 | 120篇 |
1999年 | 89篇 |
1998年 | 104篇 |
1997年 | 116篇 |
1996年 | 94篇 |
1995年 | 74篇 |
1994年 | 79篇 |
1993年 | 68篇 |
1992年 | 68篇 |
1991年 | 64篇 |
1990年 | 73篇 |
1989年 | 97篇 |
1988年 | 68篇 |
1987年 | 65篇 |
1986年 | 59篇 |
1985年 | 67篇 |
1984年 | 39篇 |
1983年 | 43篇 |
1982年 | 38篇 |
1981年 | 44篇 |
1980年 | 34篇 |
1979年 | 38篇 |
1978年 | 22篇 |
1977年 | 35篇 |
1976年 | 27篇 |
1975年 | 20篇 |
1974年 | 16篇 |
排序方式: 共有6403条查询结果,搜索用时 15 毫秒
71.
Treatment for asymptomatic anthracycline-induced cardiac dysfunction in childhood cancer survivors: the need for evidence. 总被引:1,自引:0,他引:1
E C van Dalen H J H van der Pal C van den Bos H N Caron L C M Kremer 《Journal of clinical oncology》2003,21(17):3377; author reply 3377-3377; author reply 3378
72.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
73.
Hypospadias trends in two US surveillance systems 总被引:6,自引:0,他引:6
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted. 相似文献
74.
Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred
for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination
using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with
the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was
present in 188(40 %) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild
in 51 %, moderate in 39 % and severe in 10 %. Subluxation was more prevalent in females than males (42 % vs. 37 %) and this
was most obvious in the severe group where 68 % were female. In 90 knees selected at random, four measurements of patellofemoral
morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated
with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than
150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive
to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship
to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified
more accurately and the outcomes of treatment more reliably assessed.
Received: 17 September 1999; Revised: 31 January 2000; Accepted: 4 February 2000 相似文献
75.
Robert J. Buchanan PhD ; Jane Bolin RN JD PhD ; Suojin Wang PhD ; Li Zhu PhD ; MyungSuk Kim MS 《The Journal of rural health》2004,20(2):131-135
CONTEXT: Advance directives promote patient autonomy and encourage greater awareness of final care options while reducing physician and family uncertainty regarding patient preferences. PURPOSE: To investigate differences in decision making authority and the use of advance directives among nursing home residents admitted from urban and rural areas. METHODS: A total of 551,208 admission assessments in the Minimum Data Set were analyzed for all residents admitted to a nursing facility in 2001. Using the Rural Urban Commuting Areas (RUCA) methodology and ZIP code of primary residence before admission, these residents were classified into 4 urban/rural areas. FINDINGS: Residents from rural areas were significantly more likely to have executed a durable power of attorney for health care or for financial decisions than residents admitted from the other areas, with the largest differences observed between residents admitted from urban and rural areas. Almost 6 residents in 10 from urban areas had no advance directives in place at admission compared with only 4 residents in 10 admitted from rural areas. CONCLUSIONS: Health providers and social workers in both rural and urban areas should advise patients about the value of advance directives. 相似文献
76.
Samii A Pal PK Schulzer M Mak E Tsui JK 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》2000,27(1):55-59
BACKGROUND/OBJECTIVE: The incidence of head/neck trauma preceding cervical dystonia (CD) has been reported to be 5-21%. There are few reports comparing the clinical characteristics of patients with and without a history of injury. Our aim was to compare the clinical characteristics of idiopathic CD (CD-I) to those with onset precipitated by trauma (CD-T). METHODS: We evaluated 114 consecutive patients with CD over a 9-month period. All patients were interviewed using a detailed questionnaire and had a neurological examination. Their clinical charts were also reviewed. RESULTS: Fourteen patients (12%) had mild head/neck injury within a year preceding the onset of CD. Between the two groups (CD-I and CD-T), the gender distribution (F:M of 3:2), family history of movement disorders (32% vs. 29%), the prevalence of gestes antagonistes (65% vs. 64%), and response to botulinum toxin were similar. There were non-specific trends, including an earlier age of onset (mean ages 43.3 vs. 37.6), higher prevalence of neck pain (86% vs. 100%), head tremor (67% vs. 79%), and dystonia in other body parts (23% vs. 36%) in CD-T. CONCLUSIONS: CD-I and CD-T are clinically similar. Trauma may be a triggering factor in CD but this was only supported by non-significant trends in its earlier age of onset. 相似文献
77.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
78.
A K Nag Chaudhuri Sanmoy Karmakar Dilip Roy Siddhartah Pal Mintu Pal Tuhinadri Sen 《Pharmacological research》2005,51(2):169-175
In this study, the anti-inflammatory (in reference to the cardinal signs of inflammation) and other related pharmacological activities of the hot water extract of black tea (Camellia sinensis, Sikkim variety) were evaluated along with certain standard drugs. The extract showed significant inhibitory activity against carrageenin, histamine, serotonin and prostaglandin-induced pedal inflammation. The extract inhibited exudative inflammation. The tea extract also inhibited cotton pellet-induced granuloma formation and adjuvant-induced polyarthritis. Black tea extract showed significant inhibition against glucose oxidase-mediated inflammation. The present observations establish the efficacy of this particular variety of black tea, both in the exudative and proliferative forms and as well in the chronic phase of inflammation. 相似文献
79.
80.