全文获取类型
收费全文 | 1278657篇 |
免费 | 97808篇 |
国内免费 | 1989篇 |
专业分类
耳鼻咽喉 | 18423篇 |
儿科学 | 44349篇 |
妇产科学 | 35008篇 |
基础医学 | 182162篇 |
口腔科学 | 33585篇 |
临床医学 | 111242篇 |
内科学 | 258205篇 |
皮肤病学 | 28020篇 |
神经病学 | 100357篇 |
特种医学 | 51198篇 |
外国民族医学 | 660篇 |
外科学 | 196374篇 |
综合类 | 27048篇 |
现状与发展 | 1篇 |
一般理论 | 377篇 |
预防医学 | 95714篇 |
眼科学 | 27912篇 |
药学 | 94761篇 |
2篇 | |
中国医学 | 2422篇 |
肿瘤学 | 70634篇 |
出版年
2018年 | 13131篇 |
2017年 | 9962篇 |
2016年 | 10897篇 |
2015年 | 12369篇 |
2014年 | 17162篇 |
2013年 | 26208篇 |
2012年 | 36016篇 |
2011年 | 38050篇 |
2010年 | 22798篇 |
2009年 | 21806篇 |
2008年 | 36633篇 |
2007年 | 39243篇 |
2006年 | 39498篇 |
2005年 | 38437篇 |
2004年 | 37589篇 |
2003年 | 36443篇 |
2002年 | 35793篇 |
2001年 | 63987篇 |
2000年 | 66494篇 |
1999年 | 56407篇 |
1998年 | 15128篇 |
1997年 | 13753篇 |
1996年 | 14195篇 |
1995年 | 13452篇 |
1994年 | 12765篇 |
1993年 | 11790篇 |
1992年 | 44554篇 |
1991年 | 43464篇 |
1990年 | 42216篇 |
1989年 | 40111篇 |
1988年 | 36894篇 |
1987年 | 36234篇 |
1986年 | 33618篇 |
1985年 | 32278篇 |
1984年 | 24136篇 |
1983年 | 20268篇 |
1982年 | 11723篇 |
1981年 | 10691篇 |
1980年 | 9515篇 |
1979年 | 21341篇 |
1978年 | 14821篇 |
1977年 | 12532篇 |
1976年 | 11693篇 |
1975年 | 12623篇 |
1974年 | 14661篇 |
1973年 | 14117篇 |
1972年 | 12944篇 |
1971年 | 11729篇 |
1970年 | 11050篇 |
1969年 | 10024篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
162.
163.
J. E. P. Rockell C. M. Skeaff S. M. Williams T. J. Green 《Osteoporosis international》2006,17(9):1382-1389
Introduction Vitamin D plays an important role in bone health. Our purpose was to measure serum 25-hydroxyvitamin D concentrations and their determinants in a national sample (n=2,946) of New Zealanders aged 15 years and over.Findings Mean (99% CI) serum 25-hydroxyvitamin D concentrations were 47 (45–50) nmol/l in women and 52 (49–55) nmol/l in men. Mean concentrations in New Zealand European and Others (NZEO, n=2,440), Mori (n=370), and Pacific (n=136) were 51 (49–53), 42 (38–46) and 37 (33–42) nmol/l, respectively. Three percent of New Zealanders had serum 25-hydroxyvitamin D concentrations indicative of deficiency (≤17.5 nmol/l); 48% and 84% were insufficient based on cutoffs of ≤50 and ≤80 nmol/l. Determinants of serum 25-hydroxyvitamin D concentrations in women were age, ethnicity, obesity, latitude and season; determinants in men were ethnicity and season. Serum 25-hydroxyvitamin D in women declined with age; mean concentration was 13 (8–18) nmol/l lower in women 65 years or older and 9 (5–13) nmol/l lower in women 45–64 years compared with women 15–18 years. Spring to summer differences in serum 25-hydroxyvitamin D were 31 (28–34) and 28 (25–31) nmol/l in women and men, respectively. Obese women had lower vitamin status than normal-weight women by 6 (3–10). Women living in the South Island had a mean serum 25-hydroxyvitamin D that was 6 (3–9) nmol/l lower than women living in the North Island. Ethnicity and season are the major determinants of serum 25-hydroxyvitamin D in New Zealanders.Conclusion The high prevalence of vitamin D insufficiency in New Zealanders, particularly in older women, may warrant strategies to improve vitamin D status. 相似文献
164.
H Ishihara M Bjeljac D Straumann Y Kaku P Roth Y Yonekawa 《Minimally invasive neurosurgery》2006,49(3):168-172
OBJECTIVE: A safe entry zone to tegmental lesions was identified based on intraoperative electrophysiological findings, the compound muscle action potentials (CMAP) from the extraocular muscles, and anatomic considerations. This entry zone is bordered caudally by the intramesencephalic path of the trochlear, laterally by the spinothalamic tract, and rostrally by the caudal margin of the brachium of the superior colliculus. METHODS: Four intrinsic midbrain lesions were operated upon via the safe entry zone using the infratentorial paramedian supracerebellar approach. All lesions involved the tegmentum and included an anaplastic astrocytoma, a metastatic brain tumor, a radiation necrosis, and a cavernous angioma. CMAP were bilaterally monitored from the inferior recti (for oculomotor function) and superior oblique (for trochlear nerve function) muscles. RESULTS: In three of four cases, CMAP related to the oculomotor nerve were obtained upon stimulation at the cavity wall after removal of the tumor. Stimulation at the surface of the quadrigeminal plate, however, did not cause any CMAP response. Using this monitoring as an indicator, the lesions were totally removed. CONCLUSIONS: In the surgery of tegmental lesions, CMAP monitoring from extraocular muscles is particularly helpful to prevent damage to crucial neural structures during removal of intrinsic lesions, but less so to select the site of the medullary incision. The approach via the lateral part of the colliculi is considered to be a safe route to approach the tegmental lesions. 相似文献
165.
166.
167.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population. 相似文献
168.
Zusammenfassung Dieser Artikel stellt eine Übersetzung der im Jahr 2006 herausgegebenen Empfehlungen zur Behandlung von Patienten mit spontaner intrazerebraler Blutung der Europäischen Schlaganfallinitiative (EUSI) für das Europäische Schlaganfall-Council (ESC), die Europäische Neurologische Gesellschaft (ENS) und die Europäische Förderation Neurologischer Gesellschaften (EFNS) dar.Diese EUSI-Empfehlungen werden von dem European Stroke Council (ESC), der European Neurological Society (ENS) und der European Federation of Neurological Societies (EFNS) unterstützt. 相似文献
169.
OBJECTIVES: To pilot the acceptability and feasibility of clinical audit in free and pedicled flap reconstruction. To establish a baseline flap failure rate in participating units, so that a sample size calculation could be performed for future national audit. METHODS: A proforma was piloted over a 3-month period in four participating units, during which time data on 93 reconstructive procedures involving free and pedicled flaps was collected. The patients included those where large transfers of tissue were required such as for coverage of grade IIIb compound tibial fractures and breast reconstruction after mastectomy, and also smaller flap transfers such as after skin cancer excision. RESULTS: The proforma was found to be acceptable to clinicians and the feasibility of the data collection process was established. Overall there was a total flap survival of 89% and secondary operations to the donor or recipient sites were required in 11% of patients. CONCLUSIONS: This study demonstrates the feasibility of comparative audit for free and pedicled flap procedures using the methods proposed. Based on the incidence of flap failure observed in this pilot study, at least 18 months of prospective data collection on consecutive patients is required to fulfil the statistical requirements of comparative audit. The establishment of a routinely collected minimum dataset is proposed as one means of meeting these requirements. 相似文献
170.
Abstract Migraine without aura is typically considered a female condition. The purpose of this study was to determine if there have
been any changes in the female-to-male ratio of the disease over time. We included in the study all patients with migraine
without aura (n=3457) referred to the Parma University Headache Centre between 1976 and 1995. They were divided into subgroups with respect
to gender and year-range of onset of migraine (before 1960, in the 1960s, in the 1970s, in the 1980s, and between 1990 and
1995). Gender ratio ranged from 3.6:1 (in patients with onset before 1960) to 2.8:1 (in patients with onset in the 1980s),
with no statistically significant changes during the observation period. 相似文献