全文获取类型
收费全文 | 14743篇 |
免费 | 983篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 117篇 |
儿科学 | 422篇 |
妇产科学 | 401篇 |
基础医学 | 1897篇 |
口腔科学 | 226篇 |
临床医学 | 2498篇 |
内科学 | 2581篇 |
皮肤病学 | 220篇 |
神经病学 | 1385篇 |
特种医学 | 365篇 |
外国民族医学 | 1篇 |
外科学 | 1295篇 |
综合类 | 102篇 |
一般理论 | 17篇 |
预防医学 | 1941篇 |
眼科学 | 349篇 |
药学 | 794篇 |
1篇 | |
中国医学 | 15篇 |
肿瘤学 | 1162篇 |
出版年
2023年 | 59篇 |
2022年 | 119篇 |
2021年 | 325篇 |
2020年 | 173篇 |
2019年 | 348篇 |
2018年 | 319篇 |
2017年 | 256篇 |
2016年 | 309篇 |
2015年 | 368篇 |
2014年 | 547篇 |
2013年 | 733篇 |
2012年 | 1205篇 |
2011年 | 1159篇 |
2010年 | 611篇 |
2009年 | 536篇 |
2008年 | 1054篇 |
2007年 | 1092篇 |
2006年 | 1017篇 |
2005年 | 951篇 |
2004年 | 929篇 |
2003年 | 812篇 |
2002年 | 866篇 |
2001年 | 114篇 |
2000年 | 81篇 |
1999年 | 129篇 |
1998年 | 190篇 |
1997年 | 164篇 |
1996年 | 138篇 |
1995年 | 116篇 |
1994年 | 85篇 |
1993年 | 102篇 |
1992年 | 52篇 |
1991年 | 61篇 |
1990年 | 49篇 |
1989年 | 57篇 |
1988年 | 28篇 |
1987年 | 26篇 |
1986年 | 52篇 |
1985年 | 32篇 |
1984年 | 61篇 |
1983年 | 43篇 |
1982年 | 57篇 |
1981年 | 44篇 |
1980年 | 38篇 |
1979年 | 28篇 |
1978年 | 43篇 |
1977年 | 28篇 |
1975年 | 19篇 |
1974年 | 23篇 |
1973年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Wilson's disease in children: 37-year experience and revised King's score for liver transplantation.
Anil Dhawan Rachel M Taylor Paul Cheeseman Pamela De Silva Leah Katsiyiannakis Giorgina Mieli-Vergani 《Liver transplantation》2005,11(4):441-448
Wilson's disease (WD) is a rare liver-based disorder of copper metabolism. Prognostic criteria described by our group in 1986 to predict death without transplantation have not been universally validated. The clinical features of 88 children were reviewed, retrospectively in 74 and prospectively in 14. Data from the retrospectively recruited patients that died or survived on long-term chelation were used to evaluate the validity of our old scoring system and to devise a new prognostic index, then assessed in the 14 prospectively recruited patients. Using the old scoring system, 5 children scoring > or = 7, the cutoff value for death without transplantation, survived, whereas 4 scoring < or = 7 died (sensitivity 87% and specificity 90%). A new index based on serum bilirubin, international normalized ratio, aspartate aminotransferase (AST), and white cell count (WCC) at presentation identified a cutoff score of 11 for death and proved to be 93% sensitive and 98% specific, with a positive predictive value of 88%. When the new index was evaluated prospectively in 14 patients, it predicted the need for transplantation in only the 4 who required it, although 1 child with a score of 11 survived on medical treatment. In conclusion, the new Wilson Index is more sensitive and specific in predicting mortality without transplantation than the old scoring system, but needs to be validated in a larger number of patients. 相似文献
32.
Vibrio vulnificus Septicemia After Handling Tilapia Species Fish: A Canadian Case Report and Review.
Donald C Vinh Samira Mubareka Bunmi Fatoye Pierre Plourde Pamela Orr 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2006,17(2):129-132
BACKGROUND: Vibrio vulnificus can cause a necrotizing soft tissue infection or primary septicemia; these infections are collectively known as vibriosis. This bacterium is commonly found within molluscan shellfish. Primary septicemia is often fatal, principally affecting persons with chronic liver disease. CASE PRESENTATION: A fatal case of V vulnificus sepsis that developed in a patient with chronic hepatitis B and chronic renal failure is reported. Diagnosis was made by isolation of the pathogen by blood culture. Upon further questioning, the patient's family recounted that the patient had handled and ingested Tilapia species fish in the hours preceding the patient's presentation. Despite treatment with doxycycline and cefotaxime, in conjunction with supportive care in the intensive care unit, the patient died on day 7 from multiple organ dysfunction. CONCLUSION: The present case highlights the need to consider V vulnificus in the microbiological differential diagnosis when a person presents with sepsis and bullous cutaneous lesions. The importance of educating patients with liver disease (and certain other chronic diseases) about the need to be cautious when handling or consuming seafood is underscored. 相似文献
33.
A morphometric analysis of the developing organ of Corti and its component hair cells was carried out in an age-graded series of Syrian golden hamsters with the aid of scanning electron microscopy. The purpose was to establish a quantitative framework that would provide insight into the rules and principles by which the mammalian cochlea attains its adult proportions. This study examined postnatal development at two day intervals from birth to 22 days after birth. Our analysis included measures of cochlear length and hair cell numbers as well as measures of hair cell sizes in each of five sectors along the cochlear spiral. Our results demonstrate several principles of cochlear development: (1) The full two and one-fourths turns seen in the adult cochlea are already present at birth, but the cochlea continues to elongate for the next 10–12 days. (2) Development of hair cells in the apex generally lags behind that in the base. Whereas the stereocilia and apical margins of hair cells are clearly defined in the basal turn, they become well defined in the apex only postnatally. (3) Growth in cochlear length occurs mainly by increases in cell size rather than in cell numbers; although hair cells do increase in numbers during the first 4 days of cochlear growth, this increase involves addition of hair cells only to preexisting regions of the cochlear apex. Moreover, the full complement of hair cells is established 6 days before the full size of the cochlea is attained; in contrast, hair cell growth occurs at all positions along the cochlear spiral and spans the entire period of cochlear elongation. (4) The period of hair cell growth exceeds the period of organ of Corti growth and appears to be possible by decreases in intercellular spacing, primarily in the apical region of the cochlea; inner and outer hair cell growth was complete between 16 and 18 days after birth. (5) Inner and outer hair cell neighbors remain virtually constant at different ages indicating that the spatial relationships between the two hair cell populations is preserved as the cochlea grows. (6) Comparison with previous developmental studies of auditory function in the hamster reveals that the age of 16 days after birth, when hair cells attain their mature sizes, coincides with the onset of brainstem auditory evoked responses. Growth of hair cell somas alone, however, cannot explain either the subsequent maturation of evoked potential thresholds or changes in frequency representation in the developing cochlea. © Wiley-Liss, Inc. 相似文献
34.
35.
Most patients who survive a stroke experience some degree of physical recovery. Selecting the appropriate outcome measure
to assess physical recovery is a difficult task, given the heterogeneity of stroke etiology, symptoms, severity, and even
recovery itself. Despite these complexities, a number of strategies can facilitate the selection of functional outcome measures
in stroke clinical trial research and practice. Clinical relevance in stroke outcome measures can be optimized by incorporating
a framework of health and disability, such as the International Classification of Functioning, Disability, and Health (ICF).
The ICF provides the conceptual basis for measurement and policy formulations for disability and health assessment. All outcome
measures selected should also have sound psychometric properties. The essential psychometric properties are reliability, validity,
responsiveness, sensibility, and established minimal clinically important difference. It is also important to establish the
purpose of the measurement (discriminative, predictive, or evaluative) and to determine whether the purpose of the study is
to evaluate the efficacy or effectiveness of an intervention. In addition, when selecting outcome measures and time of assessment,
the natural history of stroke and stroke severity must be regarded. Finally, methods for acquiring data must also be considered.
We present a comprehensive overview of the issues in selecting stroke outcome measures and characterize existing measures
relative to these issues. 相似文献
36.
37.
A wide variety of health care options--home-based, indigenous, and cosmopolitan--exists in northern Balochistan, Pakistan. This paper examines health-seeking behavior in the area of mother and child health for villagers in this pluralistic medical setting. The analysis of a specific series of illness episodes shows that the majority of cases obtain treatment from different medical systems for a single episode. Interest in medications takes precedence over practitioners, and the meaning the villagers attach to such substances is explored. Long-established patterns of behavior relating to indigenous medicine continue to occur when cosmopolitan medicine is utilized. Information presented here helps to explain problems in utilization of cosmopolitan pharmaceuticals and delineates areas for future health programme activity. 相似文献
38.
BACKGROUND: Modulation of the acoustic startle response by aversive sensory stimulation is a simple and objective indicator of emotionality in rodents and human beings that has been extremely valuable for the analysis of neural systems associated with fear and anxiety. We have described a paradigm for measuring fear-potentiated, whole-body acoustic startle in nonhuman primates and have developed a protocol for maintaining fear-potentiated startle over repeated sessions with minimal extinction to allow measurement of pharmacological effects on fear-potentiated startle by using within-subjects designs in relatively small groups of monkeys. METHODS: A novel, within-subjects testing protocol was used to examine the effects of three compounds in rhesus monkeys that have anxiolytic effects in rodents on fear-potentiated startle but that differ in their mechanism of action. Spontaneous vocalizations during testing also were recorded. Juvenile monkeys that were trained to associate a visual stimulus with a fear-inducing air blast to the face were tested after acute administration of different doses of buspirone diazepam, morphine, or vehicle. RESULTS: Monkeys rapidly developed a robust and persistent elevation of startle response in the presence of the CS during repeated testing sessions. Diazepam and morphine produced dose-related reductions of fear-potentiated startle. Buspirone did not significantly reduce fear-potentiated startle at the doses tested, although a trend was evident at the highest dose. All drugs reduced rates of coo vocalizations during startle testing. CONCLUSIONS: These fear-potentiated startle results suggest that rhesus monkeys have a pharmacological profile with respect to these compounds that is closer to humans than to rats. This demonstrates the value of examining the effects of drugs on fear-potentiated startle in nonhuman primates. 相似文献
39.
Normalized protein catabolic rate versus serum albumin as a nutrition status marker in pediatric patients receiving hemodialysis. 总被引:3,自引:0,他引:3
Marisa Juarez-Congelosi Pamela Orellana Stuart L Goldstein 《Journal of renal nutrition》2007,17(4):269-274
BACKGROUND: Protein-energy malnutrition occurs commonly in patients receiving hemodialysis (HD). Although serum albumin (sAlb) is recommended to monitor nutrition status in patients receiving HD, many processes unrelated to nutrition status can affect albumin concentrations. METHODS: We previously showed normalized protein catabolic rate (nPCR) to be superior to sAlb to reflect improvement in nutrition status in pediatric patients receiving maintenance HD after treatment with intradialytic parenteral nutrition for severe protein-energy malnutrition. We now compare nPCR and sAlb as nutrition status markers for pediatric patients on HD irrespective of current nutrition status. RESULTS: Forty-four patients comprising 840 months of HD provision were assessed. nPCR was higher for younger patients. Mean nPCR values were significantly lower for adolescent patients with persistent weight loss of at least 2% for at least 3 consecutive months versus patients without persistent weight loss (1.03 +/- 0.29 g/kg/d vs. 1.15 +/- 0.27 g/kg/d, P < .002), and the odds for developing persistent weight loss were four times greater for adolescent patients with nPCR less than 1 g/kg/d. No association between nPCR and weight loss was observed for younger patients. Mean sAlb levels were greater than 4 g/dL for all patient age groups and did not demonstrate a clinically significant difference between patients with or without weight loss. CONCLUSION: We suggest that nPCR may be useful for monthly nutrition status in adolescent patients receiving maintenance HD and that adolescents with nPCR less than 1 g/kg/d may be at increased risk for subsequent weight loss. 相似文献
40.