全文获取类型
收费全文 | 1753篇 |
免费 | 111篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 41篇 |
妇产科学 | 32篇 |
基础医学 | 198篇 |
口腔科学 | 42篇 |
临床医学 | 144篇 |
内科学 | 376篇 |
皮肤病学 | 48篇 |
神经病学 | 206篇 |
特种医学 | 153篇 |
外科学 | 188篇 |
综合类 | 14篇 |
一般理论 | 3篇 |
预防医学 | 151篇 |
眼科学 | 47篇 |
药学 | 114篇 |
中国医学 | 4篇 |
肿瘤学 | 93篇 |
出版年
2023年 | 19篇 |
2022年 | 23篇 |
2021年 | 71篇 |
2020年 | 38篇 |
2019年 | 65篇 |
2018年 | 59篇 |
2017年 | 39篇 |
2016年 | 33篇 |
2015年 | 52篇 |
2014年 | 60篇 |
2013年 | 61篇 |
2012年 | 124篇 |
2011年 | 112篇 |
2010年 | 55篇 |
2009年 | 61篇 |
2008年 | 104篇 |
2007年 | 115篇 |
2006年 | 107篇 |
2005年 | 82篇 |
2004年 | 84篇 |
2003年 | 63篇 |
2002年 | 55篇 |
2001年 | 19篇 |
2000年 | 15篇 |
1999年 | 28篇 |
1998年 | 20篇 |
1997年 | 12篇 |
1996年 | 14篇 |
1995年 | 11篇 |
1994年 | 12篇 |
1993年 | 12篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 15篇 |
1989年 | 18篇 |
1988年 | 13篇 |
1987年 | 19篇 |
1986年 | 16篇 |
1985年 | 7篇 |
1984年 | 9篇 |
1981年 | 6篇 |
1979年 | 11篇 |
1978年 | 5篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 14篇 |
1974年 | 16篇 |
1973年 | 5篇 |
1972年 | 7篇 |
1970年 | 5篇 |
排序方式: 共有1870条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
We present a case of aggressive fibromatosis of the scalene and longus colli muscles with surgically proved secondary involvement of the brachial plexus and carotid sheath in a 29-year-old woman in whom MR imaging failed to show involvement of the carotid sheath. The well-defined lesion was isointense on T1-weighted images and hyperintense on T2-weighted images relative to adjacent normal muscle and enhanced brightly. 相似文献
5.
6.
Debora Steiner Tomer Avidor-Reiss Ester Schallmach Daniella Saya Zvi Vogel 《Journal of molecular neuroscience : MN》1996,27(2):195-203
It was shown previously that chronic exposure to opiate agonists increases adenylyl cyclase (AC) activity, a phenomenon termed
AC superactivation (or supersensitization). More recently, we showed that acute Gi/o-coupled receptor activation inhibits the activity of several AC isozymes, including Ca2+/calmodulin-stimulated AC-I and -VIII, whereas chronic receptor activation induces their superactivation. Here, we report
that both acute μ-opioid receptor-induced inhibition and chronic induced superactivation of AC-I and -VIII are pertussis toxin
sensitive. In addition, we show that proteins that interfere with the activity of {ie195-2} subunits ({ie195-3} scavengers)
strongly attenuate the acute inhibition of AC-I and -VIII and the superactivation of AC-I, and abolish the superactivation
of AC-VIII. Based on these results, we suggest that {ie195-4} is involved in the acute inhibition and chronic agonist-induced
superactivation of AC types I and VIII. 相似文献
7.
Michael Fromm Wolfgang E. Berdel Hans D. Schick Susanne Danhauser-Riedl Ulrich Fink Wolfgang Remy Anneliese Reichert Anke Ankele Heinz W. Präuer Jörg R. Siewert Johann Rastetter 《Investigational new drugs》1988,6(3):189-194
Summary Carbetimer, a new synthetic low molecular weight polyelectrolyte with a novel structure displayed antitumor activiy in a number of animal tumor model systems and in vitro investigations. Based on these findings it was brought to a phase I clinical trial in patients with advanced malignant disease after failure of conventional treatment or with no conventional treatment available. Forty-eight patients received 98 courses. The schedule was a one hour i.v. infusion every four weeks. The starting dose was 180 mg/m2 and dose escalation was performed according to a modified Fibonacci formula up to 16,690 mg/m2. At least three patients were treated at each dose level and each patient was eligible to receive repeat courses at the same dose, until progressive disease or dose-limiting toxicity intervened. No hematological toxicity was encountered. Some adverse effects such as reversible proteinuria, hypercalcaemia, pain at infusion site, nausea and vomiting and fatigue were seen partly in a dose-related manner but did not represent the maximum tolerated dose (MTD). The limiting toxicity at the highest dose level of 16,690 mg/m2 consisted of ocular symptoms (light flashes) accompanied by a modest decrease of blood pressure and nausea or vomiting during a one hour infusion. 16,690 mg/m2/1 hour was considered the MTD. There were four deaths on study, all considered diseaserelated. Fourteen patients had stable disease for more than two courses, which, however, could also be explained by the natural course of disease. No clear-cut antitumor responses were noted in our study center.The recommended dose for phase II trials derived from our results is 12,550 mg/m2/2 hours. However, with regard to experiences in other phase I studies, the subsequent phase II studies will be performed with a dose of 6,500 mg/m2. 相似文献
8.
On the basis of animal studies, grafts of fetal human dopaminergic cells have been suggested as a therapy for Parkinson's disease. The purpose of this study was to characterize the ultrastructure and immunocytochemistry of human ventral mesencephalic xenografts placed into the catecholamine-depleted striata of athymic "nude" rats. Human fetal tissue was obtained from tissue fragments derived from elective abortions during the first trimester of pregnancy. Small pieces of the basal mesencephalon were grafted into the catecholamine-depleted striata of four athymic nude rats. The rats were allowed to survive from 3 to 6 months after grafting; following fixation, the striatal tissue containing the grafts was labeled with antibodies against tyrosine hydroxylase and serotonin. Immunocytochemistry revealed tyrosine-hydroxylase-like-immunoreactive (THLI) and serotoninlike-immunoreactive (5HTLI) cell bodies within the human grafts. Both 5HTLI and THLI fibers crossed the graft-host interface and innervated the previously lesioned striatum. Both types of fibers also entered the host cortex from the adjacent human graft. At the ultrastructural level, THLI and 5HTLI fibers and synaptic terminals were observed in the host neuropil. THLI and 5HTLI dendrites and axon terminals were also observed in the neuropil of the grafts themselves. THLI axon terminals are not normally present in the substantia nigra. The results of our study indicate that human xenografts can survive in the neuropil of the host striatum and form morphologically appropriate synapses within the host brain. 相似文献
9.
Inter and intra individual variability of acute insulin response during intravenous glucose tolerance tests 总被引:1,自引:0,他引:1
S Bardet C Pasqual D Maugendre J P Remy B Charbonnel P Sai 《Diabète & métabolisme》1989,15(5):224-232
To analyze the inter- and intra-individual variability of acute insulin response to intravenous glucose (AIRG), 41 healthy volunteers underwent an intravenous glucose tolerance test (IVGTT) and 29 of them a second IVGTT 1 to 9 months later. Basal glycemic, insulin (IRI), and C-peptide values were similar for both IVGTTs. Different indices were used to estimate AIRG. A great inter-individual variability of AIRG (CV around 60%) was detected. AIRGs were not statistically different between the two IVGTTs, and the within-subject variation was fair at the group level (CVs approximately 30%). However, individual coefficients of variation ranged from 2 to 60% between the two tests. Moreover, subjects considered as "low" responders during test 1, returned to "normal" values during test 2. Conversely, other subjects dropped to a "low" response in IVGTT 2. Insulin peak (IRI max) occurred between 1 and 3 minutes after glucose infusion in 85% of the control population, but time points of IRI max were different for 45% of the population between the two IVGTTs. These results suggest that AIRG during IVGTTs are reproducible at the group level, but that AIRG has to be interpreted with caution in individual early detection of pre-insulin-dependent diabetes mellitus because inter- and intra-individual variability could be high even for some normal subjects. 相似文献
10.
Clinical evidence of the nonpathogenic nature of the M34T variant in the connexin 26 gene 总被引:2,自引:0,他引:2
Feldmann D Denoyelle F Loundon N Weil D Garabedian EN Couderc R Joannard A Schmerber S Delobel B Leman J Journel H Catros H Ferrec C Drouin-Garraud V Obstoy MF Moati L Petit C Marlin S 《European journal of human genetics : EJHG》2004,12(4):279-284
Mutations in GJB2 are the most common cause of congenital nonsyndromic hearing loss. The controversial allele variant M34T has been hypothesized to cause autosomal dominant or recessive nonsyndromic hearing impairment and some in vitro data has been consistent with this hypothesis. In this report, we present the clinical and genotypic study of 11 families (seven familial forms of nonsyndromic sensorineural hearing loss (NSSNHL) and four sporadic cases) in which the M34T GJB2 variant has been identified. The M34T mutation did not segregate with the deafness in six of the seven familial forms of NSSNH. Eight persons with normal audiogram presented a heterozygous M34T variation and five normal hearing individuals were composite heterozygous for M34T and another GJB2 mutation. Four normal hearing individuals with a documented audiogram were M34T/35delG and one was M34T/(GJB6-D13S1830)del. Screening a French control population of 116 subjects we have found an M34T allele frequency of 1.72%. This percentage was not significatively different from the prevalence of the M34T allele in the deaf population, which was 2.12%. All these data suggest that the M34T variant is not clinically significant in human and is a frequent polymorphism in France. 相似文献