全文获取类型
收费全文 | 1871篇 |
免费 | 128篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 83篇 |
妇产科学 | 90篇 |
基础医学 | 279篇 |
口腔科学 | 25篇 |
临床医学 | 210篇 |
内科学 | 342篇 |
皮肤病学 | 19篇 |
神经病学 | 181篇 |
特种医学 | 41篇 |
外科学 | 217篇 |
综合类 | 22篇 |
一般理论 | 1篇 |
预防医学 | 253篇 |
眼科学 | 14篇 |
药学 | 109篇 |
肿瘤学 | 101篇 |
出版年
2024年 | 3篇 |
2023年 | 26篇 |
2022年 | 33篇 |
2021年 | 105篇 |
2020年 | 59篇 |
2019年 | 68篇 |
2018年 | 66篇 |
2017年 | 58篇 |
2016年 | 73篇 |
2015年 | 71篇 |
2014年 | 82篇 |
2013年 | 118篇 |
2012年 | 169篇 |
2011年 | 152篇 |
2010年 | 87篇 |
2009年 | 74篇 |
2008年 | 119篇 |
2007年 | 118篇 |
2006年 | 88篇 |
2005年 | 92篇 |
2004年 | 73篇 |
2003年 | 63篇 |
2002年 | 63篇 |
2001年 | 28篇 |
2000年 | 18篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 1篇 |
1990年 | 9篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1983年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1973年 | 2篇 |
1970年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有2004条查询结果,搜索用时 31 毫秒
101.
102.
103.
Michael Feuerstein Gina M. Luff Cherise B. Harrington Cara H. Olsen 《Journal of cancer survivorship》2007,1(3):185-192
Background The Americans with Disability Act (ADA) claim patterns can provide information on sources of potential work discrimination
faced by employees with various health problems. This study investigated the pattern of ADA disputes among cancer survivors
and non-cancer related impairments.
Materials and methods Using multivariable logistic regression adjusting for demographics, employees with cancer related claims were compared to
employees with other impairment related claims for alleged violations from 2000 to 2005. The impairments were grouped into
orthopedic, behavioral, medical, neurologica1, sensory, cancer, cancer comorbid (cancer and non-cancer impairments), and comorbid
“other” (non-cancer comorbid disorders). The dispute categories included: termination, reasonable accommodation, relations,
terms, hiring, and a nonspecific “other” category.
Results This study analyzed 59,981 cases over a 6 year period. All comparisons were made in relation to the cancer group. There was
a protective effect for any impairment other than cancer (OR = 0.29–0.63, 95% CI = 0.25–0.72) related to discharge from work.
Also, orthopedic (OR = 0.81, 95% CI = 0.71–0.93), general medical (OR = 0.82, 95% CI = 0.72–0.94), and neurological (OR = 0.83,
95% CI = 0.71–0.96) impairments were found to be protective for claims related to terms of employment relative to cancer.
Cancer survivors who reported a second impairment in addition to cancer were more likely to file disputes that involved relations
with others at work (OR = 1.47, 95% CI = 1.16–1.87) in comparison to those with cancer only. Orthopedic (OR = 2.42, 95% CI = 2.13–2.76),
neurological (OR = 1.50, 95% CI = 1.30–1.72), and sensory (OR = 1.50, 95% CI = 1.29–1.73) groups were more likely to file
accommodation related disputes than the cancer group. Sensory (OR = 4.41, 95% CI = 3.45–5.63), other-comorbid (OR = 2.33,
95% CI = 1.85–2.94), medical (OR = 1.92, 95% CI = 1.51–2.44), and neurological (OR = 1.59, 95% CI = 1.23–2.05) impairment
groups filed more disputes related to hiring than the cancer or the cancer-comorbid group.
Conclusion Cancer survivors are more likely to file job loss claims and differential treatment related to workplace policies. Those with
cancer and another impairment file more claims related to relationship problems at work than cancer only. The factors accounting
for these claims need to be explored in future research in order to develop more specific evidence based policy and practice.
Implications for cancer survivors While the percentage of cancer survivors who file claims are relatively small, job termination and terms of employment are
more likely to be concerns for cancer survivors than employees with other types of impairments. If a cancer survivor has another
health problem as well relationship disputes are likely to emerge.
The opinions and assertions contained herein are the private views of the authors and are not to be construed as being official
or as reflecting the views of the Uniformed Services University of the Health Sciences or the Department of Defense. 相似文献
104.
Andrea Carter Wendy Landier Amy Schad Allison Moser Alexandra Schaible Cara Hanby Seira Kurian F Lennie Wong Doojduen Villaluna Smita Bhatia 《Cancer epidemiology, biomarkers & prevention》2008,17(7):1665-1673
The immense progress made in childhood cancer survival has been due to the systematic and efficient conduct of large multicenter therapeutic trials, using the infrastructure developed by national cooperative groups. These therapeutic trials have been successful, in part due to the high participation rates by the participating member institutions. However, participation in nontherapeutic trials in the cooperative group setting has lagged behind that of therapeutic trials for a variety of reasons, such as lack of institutional resources, leading to low priority given to such activities. The purpose of this report is to share some of the methods developed and successfully implemented by a coordinating center (City of Hope National Medical Center) to maximize institutional participation and patient enrollment and to standardize data collection and quality control, in order to ensure the successful execution of two large, extramurally funded, cooperative group nontherapeutic studies. To date, over 175 institutions have obtained regulatory approval for the protocols showcased here, accrual has been on target, and completeness and quality of the collected data have been excellent. The successful execution of these nontherapeutic studies shows the advantages of diverse study publicity techniques, detailed standardized operating procedures, and effective utilization of technological resources. 相似文献
105.
We tested the hypothesis that growth hormone (GH) mediates the rise in insulin-like growth factor I (IGF-I) concentrations in children with precocious puberty. We studied three groups of patients. Group 1 included six children with GH deficiency and precocious puberty (precocious GH-deficient); group 2 included 10 GH-sufficient patients with idiopathic true precocious puberty (precocious GH-sufficient); and group 3 included 9 prepubertal children with GH deficiency (prepubertal GH-deficient). Growth rates, pubertal status, and plasma IGF-I concentrations were determined at regular intervals. The precocious children with GH deficiency had a mean (+/- SD) growth rate of 7.2 +/- 2.1 significantly below that of the precocious GH-sufficient patients (10.5 +/- 2.5 cm/yr, p less than 0.05) but above that of the prepubertal GH-deficient children (3.9 +/- 1.4 cm/yr, p less than 0.05). The mean IGF-I concentration in the precocious GH-deficient children was 0.77 +/- 0.39 U/ml, significantly lower than the mean level of 2.2 +/- 0.67 U/ml in the precocious GH-sufficient patients (p less than 0.01). However, precocious GH-deficient patients had significantly higher IGF-I values than the prepubertal GH-deficient children (0.24 +/- 0.10 U/ml, p less than 0.05). IGF-I values did not rise with the onset of precocious puberty in four of the precocious GH-deficient children evaluated before and after the development of precocious puberty. However, three patients who began GH treatment did have a rise in plasma IGF-I concentrations to levels of 1.2, 3.4, and 3.7 U/ml, respectively. These findings are compatible with the concept that sex steroids increase IGF-I levels in precocious puberty primarily by increasing GH production. A small but direct effect of sex steroids on IGF-I production may also exist. The onset of precocious puberty in children with organic GH deficiency may mask the abnormal growth pattern of these children and delay diagnosis; determinations of plasma IGF-I concentrations may be helpful in assessing the GH status of these patients. 相似文献
106.
Frankenfeld CL Patterson RE Kalhorn TF Skor HE Howald WN Lampe JW 《Journal of the American Dietetic Association》2002,102(10):1407-1413
OBJECTIVE: To validate assessment of soy intake using food frequency questionnaires (FFQs) compared with plasma isoflavone (genistein and daidzein) concentrations. DESIGN: Cross-sectional analysis of soy isoflavone intake and plasma analysis of isoflavones. SUBJECTS: 77 men and women, age range 20 to 40 years, recruited from the Seattle metropolitan area. MAIN OUTCOME MEASURES: Isoflavone intake was determined from responses to a 40-item soy FFQ and from tofu and soymilk intake assessed as part of a comprehensive FFQ used for the Women's Health Initiative (WHI FFQ). Isoflavone concentrations in fasting blood samples were determined by liquid chromatography-mass spectrometry. STATISTICAL ANALYSES: Correlation coefficients were calculated for: a) isoflavone intake assessed by the soy FFQ and the WHI FFQ, b) intake assessed by the soy FFQ and plasma isoflavone concentrations, and c) intake assessed by the WHI FFQ and plasma isoflavone concentrations. RESULTS: Isoflavone intake was highly correlated between the soy FFQ and the WHI FFQ (r = 0.84). Genistein and daidzein intakes determined by the soy FFQ were significantly correlated with plasma concentrations (r = 0.53 and 0.45, respectively). Isoflavone intake assessed from the WHI FFQ was also correlated with plasma concentration (r = 0.46 and 0.45). Soymilk and tofu were the two major contributors to isoflavone intake (38.6%). CONCLUSIONS: A soy-specific, 40-item FFQ assessed isoflavone intake with good validity. Isoflavone intake assessed by the WHI FFQ (tofu and soymilk) had lower correlations with plasma concentrations compared with the soy FFQ. Nonetheless, assessment of the two foods is a reasonably good marker for soy food consumption in this sample. 相似文献
107.
Pereira MA Ebbeling CB Pawlak DB Leidig MM Ludwig DS 《The American journal of clinical nutrition》2002,76(5):1140-1; author reply 1141-2
108.
Gogtay N Sporn A Alfaro CL Mulqueen A Rapoport JL 《Journal of child and adolescent psychopharmacology》2002,12(4):347-349
Akathisia is a relatively rare side effect with the newer atypical antipsychotic agents, particularly clozapine, and is easily misdiagnosed in children. As children are often unable to describe their symptoms verbally, their akathisia can be misdiagnosed as worsening of their psychosis, prompting an unnecessary increase in their neuroleptic dose. Two cases of childhood-onset schizophrenia associated with clozapine-induced akathisia responsive to beta-blocker treatment are described. Akathisia should be considered in all cases of apparent nonresponse to atypical antipsychotics. 相似文献
109.
Menor C Fueyo J Escribano O Piña MJ Redondo P Cara C Román ID Fernández-Moreno MD Guijarro LG 《Multiple sclerosis (Houndmills, Basingstoke, England)》2002,8(3):243-248
The present study was performed in order to obtain the thiopurine methyltransferase (TPMT) activity frequency distribution histogram in a Spanish population. A total of 3640 Spanish clinical laboratory samples were evaluated, which included 1249 patients with Crohn's disease, 589 with ulcerative colitis, 348 with multiple sclerosis (MS), 487 with several autoimmune diseases different from the above-mentioned diseases and 967 a donor group. We have measured the TPMT activity in red blood cells (RBCs) by a radiochemical method, using S-adenosyl-L-[methyl-3H]methionine as methyl donor. The different groups present in their entirety a normal distribution histogram and a wide range of TPMT activity from 0 to 41 U/ml RBCs. The differences found between the Spanish population TPMT activity frequency distribution histogram and the pattern previously described in a North American population were not due to azathioprine treatment or gender. The effect of autoimmune diseases on TPMT activity was evaluated: the enzymatic activity was similar in the donor group (19.9 +/- 6.3 U/ml RBCs) and in the patients with Crohn's disease (20.0 +/- 5.8 U/ml RBCs) and ulcerative colitis (19.7 +/- 6.1 U/ml RBCs); however, it decreased significantly (p<0.0001) in MS patients (17.1 +/- 6.1 U/ml RBCs) with respect to the donor group. In conclusion, our results show that the Spanish population TPMT distribution is closer to that of the Jewish population of Israel than to North American populations, and that in MS the enzymatic activity of TPMT decreases significantly. This observation may take into account the usage of azathioprine as therapeutic agent in Spanish MS patients. 相似文献
110.
Filiano JJ Goldenthal MJ Mamourian AC Hall CC Marín-García J 《Pediatric neurology》2002,26(3):239-242
Leigh syndrome is a heterogenous neurologic disease characterized by seizures, developmental delay, muscle weakness, respiratory abnormalities, optic abnormalities, including atrophy and ophthalmoplegia, and progressive cranial nerve degeneration with early onset in infants and children. Diagnosis can be confirmed by characteristic pathologic findings of necrosis in the basal ganglia, thalamus, and brainstem. Severe dysfunction of mitochondrial energy metabolism is generally present and involved in the etiology of this degenerative central nervous system disease. At the molecular level, a number of point mutations have been located in mitochondrial DNA genes, including ATPase6 and tRNA(Lys) genes, and in nuclear genes encoding subunits of oxidative enzymes, such as pyruvate dehydrogenase. Biochemically these mutations are responsible for enzymatic defects in either respiratory complexes (I, IV, or V) or pyruvate dehydrogenase. We describe here the first case of Leigh syndrome with marked depletion of mitochondrial DNA levels in skeletal muscle and abnormal activities in skeletal muscle of mitochondrial respiratory complexes I, III, IV, and V. 相似文献