全文获取类型
收费全文 | 1003971篇 |
免费 | 75793篇 |
国内免费 | 2628篇 |
专业分类
耳鼻咽喉 | 13011篇 |
儿科学 | 34780篇 |
妇产科学 | 28640篇 |
基础医学 | 146038篇 |
口腔科学 | 27817篇 |
临床医学 | 91089篇 |
内科学 | 194637篇 |
皮肤病学 | 22950篇 |
神经病学 | 79757篇 |
特种医学 | 38634篇 |
外国民族医学 | 306篇 |
外科学 | 150556篇 |
综合类 | 23874篇 |
一般理论 | 387篇 |
预防医学 | 78495篇 |
眼科学 | 22729篇 |
药学 | 72336篇 |
3篇 | |
中国医学 | 2034篇 |
肿瘤学 | 54319篇 |
出版年
2018年 | 10661篇 |
2017年 | 8316篇 |
2016年 | 9461篇 |
2015年 | 10692篇 |
2014年 | 14537篇 |
2013年 | 22228篇 |
2012年 | 29263篇 |
2011年 | 31153篇 |
2010年 | 18642篇 |
2009年 | 17553篇 |
2008年 | 29057篇 |
2007年 | 30761篇 |
2006年 | 31264篇 |
2005年 | 29910篇 |
2004年 | 29194篇 |
2003年 | 28050篇 |
2002年 | 27042篇 |
2001年 | 47148篇 |
2000年 | 48272篇 |
1999年 | 40467篇 |
1998年 | 11292篇 |
1997年 | 10169篇 |
1996年 | 10237篇 |
1995年 | 9846篇 |
1994年 | 9159篇 |
1993年 | 8539篇 |
1992年 | 32400篇 |
1991年 | 31603篇 |
1990年 | 31158篇 |
1989年 | 30000篇 |
1988年 | 27296篇 |
1987年 | 27444篇 |
1986年 | 25550篇 |
1985年 | 24714篇 |
1984年 | 18512篇 |
1983年 | 15602篇 |
1982年 | 9339篇 |
1981年 | 8427篇 |
1979年 | 16948篇 |
1978年 | 12280篇 |
1977年 | 10368篇 |
1976年 | 9796篇 |
1975年 | 10241篇 |
1974年 | 12383篇 |
1973年 | 11905篇 |
1972年 | 10945篇 |
1971年 | 10140篇 |
1970年 | 9409篇 |
1969年 | 8754篇 |
1968年 | 8137篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
S. Moss H. Prosser B. Ibbotson D. Goldberg 《Journal of intellectual disability research : JIDR》1996,40(5):457-465
This paper investigates differences in the nature and frequency of psychiatric symptoms reported by patients with learning disability and by key informants. The study involved psychiatric assessment of 100 patients with learning disabilities and key informants using the Psychiatric Assessment Schedule for Adults with a Developmental Disability (PAS-ADD), a semi-structured psychiatric interview developed specifically for people who have a learning disability. There was considerable disagreement between respondent and informant interviews; only 40.7% of cases were detected by both interviews. Respondents were more likely to report on autonomic symptoms and certain psychotic phenomena. Other anxiety and depression symptoms were more frequently reported by infcrnnants. The results indicate that it is crucial for sensitive case detection to complete both interviews where possible. If the respondent cannot be interviewed, panic disorder or phobias may be particularly difficult to detect. 相似文献
993.
Anthropology, and its supposed operationalisation within transcultural nursing, is becoming increasingly prominent in educational curricula in the U.K. This increase in interest is driven both by governmental pressure to provide more culturally appropriate care, and an intuitive notion that anthropology, nursing and other related professions such as midwifery have a common basis of mutually overlapping and re-enforcing theory and practice. This paper explores the question of whether there is a natural alliance between anthropology, and the applied aspects of health care disciplines such as nursing and midwifery, by examining some of the concepts underlying each discipline, and the ways in which these concepts are applied in practice. Anthropology is the study of culture, and it is suggested that a more complete understanding of this central concept is essential if it is to be utilised in the applied disciplines encompassed by the practice of nursing and midwifery. 相似文献
994.
M. Vrethem B. Lindvall S. Kihlstrand E. Bckman T. Brismar P. Fredman K.G. Henriksson 《European journal of neurology》1996,3(2):156-159
We report improvement in muscle strength in a patient with multifocal motor neuropathy (MMN) when given high-dose intravenous immunoglobin (i.v.-Ig) treatment. The patient had asymmetrical limb weakness, atrophy and absent or weak reflexes, but no sensory disturbances. Neurography showed multiple conduction blocks in peripheral motor nerves but no sensory nerve abnormalities. Serum and anti-GM1 antibodies were not found, however, the patient had serum antibodies against the glycolipid LK1, an epitope found both in glycolipid and also in some glycoproteins in peripheral nerve myelin. Muscle strength improved 5 days after i.v.-Ig therapy, and lasted about 10 weeks. Repeated courses of treatment resulted in similar improvement. This is, to our knowledge, the first patient reported with MMN found to have antibodies against the glycolipid LK1. 相似文献
995.
996.
Patient classification systems: strategies for the 1990s 总被引:2,自引:0,他引:2
B Nagaprasanna 《Nursing management》1988,19(3):105-6, 108, 112
997.
E D Kroese G Bannenberg P Dogterom A B Noach J F Nagelkerke J H Meerman 《Biochemical pharmacology》1990,40(8):1885-1892
Freshly isolated rat hepatocytes were used to study the mechanism of cell death induced by N-hydroxy-2-acetylaminofluorene (N-OH-AAF). Exposure to 1.0 mM N-OH-AAF resulted in more than 90% cell death (as measured by LDH leakage) of hepatocytes isolated from male rats within 6 hr. Only 36% of the hepatocytes isolated from female rats died within this period. When inorganic sulfate was omitted from the incubation medium, a 6 hr exposure to 1.0 mM N-OH-AAF resulted in only 40% cell death of male hepatocytes. These findings are in accordance with the sex difference and sulfation dependence of N-OH-AAF hepatotoxicity observed in the rat in vivo. N-OH-AAF decreased glutathione (GSH) in male hepatocytes in a concentration-dependent manner. This GSH consumption was only partly dependent on the presence of inorganic sulfate. No lipid peroxidation was observed during N-OH-AAF exposure; N-OH-AAF even prevented endogenous and diethyl maleate (DEM)-induced lipid peroxidation. No reduction of free protein thiol groups was found after exposure to N-OH-AAF, even after 75% cell death had occurred. A reduction of protein thiols after N-OH-AAF exposure was observed in GSH depleted hepatocytes (obtained by DEM plus vitamin E pretreatment). Under these conditions N-OH-AAF-induced cell death occurred earlier. Therefore, GSH protects against protein thiol depletion by N-OH-AAF in control cells. N-OH-AAF-induced cell death was preceded by a loss of intracellular ATP. It is concluded, therefore, that neither lipid peroxidation nor depletion of protein thiols, but possibly loss of intracellular ATP, is involved in the sulfation-dependent cytotoxic mechanism of N-OH-AAF in isolated rat hepatocytes. 相似文献
998.
K K Valu T A Gourdie T J Boritzki G L Gravatt B C Baguley W R Wilson L P Wakelin P D Woodgate W A Denny 《Journal of medicinal chemistry》1990,33(11):3014-3019
Four series of acridine-linked aniline mustards have been prepared and evaluated for in vitro cytotoxicity, in vivo antitumor activity, and DNA cross-linking ability. The anilines were attached to the DNA-intercalating acridine chromophores by link groups (-O-, -CH2-, -S-, and -SO2-) of widely varying electronic properties, providing four series of widely differing mustard reactivity where the alkyl chain linking the acridine and mustard moieties was varied from two to five carbons. Relationships were sought between chain length and biological properties. Within each series, increasing the chain length did not alter the reactivity of the alkylating moiety but did appear to position it differently on the DNA, since cross-linking ability (measured by agarose gel assay) altered with chain length, being maximal with the C4 analogue. The in vivo antitumor activities of the compounds depended to some extent on the reactivity of the mustard, with the least reactive SO2 compounds being inactive. However, DNA-targeting did appear to allow the use of less reactive mustards, since the S-linked acridine mustards showed significant activity whereas the parent S-mustard did not. Within each active series, the most active compound was the C4 homologue, suggesting some relationship between activity and extent of DNA alkylation. 相似文献
999.
We assessed the ability of three monoclonal antibodies (MAbs) (5E8, 5C7, and 1F10) to detect tumor-associated antigens (TAAs) in the sera of patients seen in consultation by the Pulmonary Disease Section at the Philadelphia Veterans Administration Medical Center from September through November 1987. Eighteen of the 61 sera were obtained from patients with histologically established lung cancer. Using a semiquantitative enzyme-linked immunoassay (ELISA), TAAs were detected by the MAb panel in the sera of 12 lung cancer patients, yielding a sensitivity of 67% with a 95% confidence interval of 44 to 84%. The frequency of TAA detection varied among cell types and stages of disease. There were eight false positives and 35 true negatives, giving a specificity of 81% with a 95% confidence interval of 67 to 90%. Two of the false positives came from patients with nonpulmonary tumors known to cross-react with the MAbs (laryngeal and gastric carcinoma). The panel was able to distinguish patients with lung cancer from those without to a highly significant degree (chi 2 = 11.2 with 1 df, p less than 0.001). This study suggests that MAb-mediated detection of serum TAAs may be useful in diagnosing and characterizing lung cancers. 相似文献
1000.
The effect of ketanserin (3 mg/kg i.v.) on the baroreceptor heart rate reflex and the Bezold-Jarisch reflex was examined in conscious Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). In the control situation (before ketanserin treatment), reflex bradycardia in response to phenylephrine (baroreflex) and phenyldiguanide (Bezold-Jarisch reflex) were impaired in SHR as compared with WKY, while reflex tachycardia in response to nitroprusside was similar in the two groups. However, after ketanserin administration in SHR, there was a reversal of the baroreflex-mediated tachycardia in response to nitroprusside into a bradycardic response. The nitroprusside-induced bradycardia was not caused by the release of 5-HT stimulating chemosensitive vagal afferents since the 5-HT3 receptor antagonist MDL 72222 did not block this response. In the same SHR, the Bezold-Jarisch reflex evoked by phenyldiguanide and the phenylephrine-induced bradycardia were potentiated by ketanserin. All the above effects of ketanserin were less evident in the WKY. Ketanserin did not alter vagal efferent function in anaesthetized SHR since it did not affect bradycardia induced by electrical stimulation of the vagus nerve. Therefore, it is suggested that ketanserin has sensitised cardiac vagal afferent mechanisms in SHR, which led to a normalization of reflex bradycardic function to a level normally observed in conscious normotensive WKY (i.e. prior to ketanserin treatment). 相似文献