全文获取类型
收费全文 | 9061篇 |
免费 | 793篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 411篇 |
妇产科学 | 180篇 |
基础医学 | 1424篇 |
口腔科学 | 324篇 |
临床医学 | 991篇 |
内科学 | 1628篇 |
皮肤病学 | 150篇 |
神经病学 | 1058篇 |
特种医学 | 289篇 |
外科学 | 994篇 |
综合类 | 204篇 |
一般理论 | 10篇 |
预防医学 | 784篇 |
眼科学 | 112篇 |
药学 | 716篇 |
中国医学 | 30篇 |
肿瘤学 | 576篇 |
出版年
2021年 | 132篇 |
2020年 | 96篇 |
2019年 | 141篇 |
2018年 | 150篇 |
2017年 | 117篇 |
2016年 | 129篇 |
2015年 | 131篇 |
2014年 | 185篇 |
2013年 | 290篇 |
2012年 | 432篇 |
2011年 | 400篇 |
2010年 | 268篇 |
2009年 | 207篇 |
2008年 | 412篇 |
2007年 | 392篇 |
2006年 | 374篇 |
2005年 | 374篇 |
2004年 | 336篇 |
2003年 | 351篇 |
2002年 | 320篇 |
2001年 | 285篇 |
2000年 | 286篇 |
1999年 | 235篇 |
1998年 | 114篇 |
1997年 | 96篇 |
1996年 | 75篇 |
1995年 | 93篇 |
1994年 | 78篇 |
1993年 | 78篇 |
1992年 | 183篇 |
1991年 | 219篇 |
1990年 | 165篇 |
1989年 | 207篇 |
1988年 | 222篇 |
1987年 | 253篇 |
1986年 | 204篇 |
1985年 | 238篇 |
1984年 | 147篇 |
1983年 | 99篇 |
1982年 | 79篇 |
1981年 | 82篇 |
1980年 | 73篇 |
1979年 | 106篇 |
1978年 | 113篇 |
1977年 | 98篇 |
1976年 | 69篇 |
1975年 | 76篇 |
1974年 | 77篇 |
1973年 | 72篇 |
1972年 | 72篇 |
排序方式: 共有9904条查询结果,搜索用时 15 毫秒
1.
Suchi Raghunathan Corey L. Reynolds Robert J. Schwartz M. David Stewart Bradley K. McConnell 《Fundamental & clinical pharmacology》2019,33(1):25-30
Inbred mouse strains are the most widely used mammalian model organism in biomedical research owing to ease of genetic manipulation and short lifespan; however, each inbred strain possesses a unique repertoire of deleterious homozygous alleles that can make a specific strain more susceptible to a particular disease. In the current study, we report dystrophic cardiac calcinosis (DCC) in C.B‐17 SCID male mice at 10 weeks of age with no significant change in cardiac function. Acquisition of DCC was characterized by myocardial injury, fibrosis, calcification, and necrosis of the tissue. At 10 weeks of age, 38% of the C.B‐17 SCID mice from two different commercial colonies exhibited significant calcinosis on the ventricular epicardium, predominantly on the right ventricle. The frequency of calcinosis was more than 50% for mice obtained from Taconic's Cambridge City colony and 25% for mice obtained from Taconic's German Town colony. Interestingly, the DCC phenotype did not affect cardiac function at 10 weeks of age. No differences in echocardiography or electrocardiography were observed between the calcinotic and non‐calcinotic mice from either colony. Our findings suggest that C.B‐17 SCID mice exhibit DCC as early as 10 weeks of age with no significant impact on cardiac function. This strain of mice should be cautiously considered for the study of cardiac physiology. 相似文献
2.
Ferdynand Hebal Elissa Port Catherine J. Hunter Bryan Malas Jared Green Marleta Reynolds 《Journal of pediatric surgery》2019,54(4):656-662
Background/purpose
Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.Methods
From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.Results
Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).Conclusions
WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.Level of Evidence
IV.Type of Study
Diagnostic Study. 相似文献3.
4.
Dwight W. Reynolds M.D. F.H.R.S. 《Pacing and clinical electrophysiology : PACE》2006,29(10):1186-1186
5.
6.
Sodium MRI of the human kidney at 3 Tesla. 总被引:6,自引:0,他引:6
Nimrod Maril Yael Rosen Glenn H Reynolds Alex Ivanishev Long Ngo Robert E Lenkinski 《Magnetic resonance in medicine》2006,56(6):1229-1234
The sodium concentration gradient in the kidney (from the cortex to the medulla) serves to regulate fluid homeostasis and is tightly coupled to renal function. It was previously shown that renal function and pathophysiology can be characterized in rat kidneys by measuring the sodium gradient with (23)Na MRI. This study demonstrates for the first time the ability of (23)Na MRI to map the distribution of sodium in the human kidney and to quantify the corticomedullary sodium gradient. The study was performed on a 3T Signa LX scanner (GE) using an in-house-built quadrature surface coil. (23)Na images of volunteers were acquired using a 3D coronal gradient-echo sequence at a spatial resolution of 0.3 x 0.3 x 1.5 cm(3) in a 25-min scan time. The signal intensity (relative to the noise) increased linearly from the cortex to each of the medullae with a mean slope of 1.6 +/- 0.2 in relative arbitrary units per mm (Rel.u./mm, N = 6) and then decreased, as expected, toward the renal pelvis. Water deprivation (12 hr) induced a significant increase of 25% (P < 0.05) in this gradient. Based on these results, we suggest that sodium MRI can serve as a valuable noninvasive method for functional imaging of the human kidney. 相似文献
7.
In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed. 相似文献
8.
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Intrathecal morphine in an average dose of 0.01 mg/kg was given to 33 patients between ages 11 and 16 years who had spinal arthrodesis for idiopathic scoliosis. The morphine was administered intrathecally as a 10 cc bolus at the conclusion of the arthrodesis, but before closure. The goal was to study safety in terms of respiratory depression and pain relief. Respirations occurred spontaneously in 30 of the 33 patients within 15 minutes of cessation of anesthesia. Respiratory depression occurred in five patients, four of whom had arterial blood pCO2 levels greater than 60 mm Hg. Thirty-one patients had relief of pain for 8 to greater than 40 hours, averaging 18 hours. Two patients had no noticeable pain relief. There appeared to be no relation between dose and pain relief in this limited dose range. We were unable to duplicate the long duration of pain relief reported elsewhere. We also were unable to decrease the side effects of respiratory depression and nausea to a level reported by others. It may be that the 10 cc bolus injected intrathecally circulates to the brain and ventricles faster than desired, or that factors relating to type of anesthesia or dose need to be considered. Low-dose intrathecal morphine does provide noticeable pain relief in younger patients undergoing spinal fusion. The side effects of nausea and respiratory depression can be managed safely with medication. 相似文献
10.