全文获取类型
收费全文 | 1294016篇 |
免费 | 98831篇 |
国内免费 | 2051篇 |
专业分类
耳鼻咽喉 | 18692篇 |
儿科学 | 44657篇 |
妇产科学 | 35265篇 |
基础医学 | 184322篇 |
口腔科学 | 35319篇 |
临床医学 | 112475篇 |
内科学 | 261335篇 |
皮肤病学 | 28388篇 |
神经病学 | 101518篇 |
特种医学 | 51507篇 |
外国民族医学 | 660篇 |
外科学 | 197990篇 |
综合类 | 27085篇 |
现状与发展 | 1篇 |
一般理论 | 380篇 |
预防医学 | 97649篇 |
眼科学 | 28077篇 |
药学 | 95917篇 |
2篇 | |
中国医学 | 2576篇 |
肿瘤学 | 71083篇 |
出版年
2019年 | 9627篇 |
2018年 | 13782篇 |
2017年 | 10455篇 |
2016年 | 11362篇 |
2015年 | 13008篇 |
2014年 | 17938篇 |
2013年 | 27128篇 |
2012年 | 37368篇 |
2011年 | 39573篇 |
2010年 | 23571篇 |
2009年 | 22393篇 |
2008年 | 37605篇 |
2007年 | 40204篇 |
2006年 | 40281篇 |
2005年 | 39131篇 |
2004年 | 38127篇 |
2003年 | 36918篇 |
2002年 | 36186篇 |
2001年 | 64174篇 |
2000年 | 66674篇 |
1999年 | 56547篇 |
1998年 | 15179篇 |
1997年 | 13798篇 |
1996年 | 14222篇 |
1995年 | 13480篇 |
1994年 | 12799篇 |
1993年 | 11810篇 |
1992年 | 44606篇 |
1991年 | 43529篇 |
1990年 | 42253篇 |
1989年 | 40154篇 |
1988年 | 36926篇 |
1987年 | 36258篇 |
1986年 | 33647篇 |
1985年 | 32308篇 |
1984年 | 24153篇 |
1983年 | 20289篇 |
1982年 | 11731篇 |
1981年 | 10702篇 |
1979年 | 21362篇 |
1978年 | 14833篇 |
1977年 | 12545篇 |
1976年 | 11698篇 |
1975年 | 12632篇 |
1974年 | 14667篇 |
1973年 | 14136篇 |
1972年 | 12951篇 |
1971年 | 11740篇 |
1970年 | 11059篇 |
1969年 | 10039篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
Chromogenic ionophore-based methods for spectrophotometric assay of sodium and potassium in serum and plasma 总被引:1,自引:0,他引:1
A Kumar E Chapoteau B P Czech C R Gebauer M Z Chimenti O Raimondo 《Clinical chemistry》1988,34(9):1709-1712
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers. 相似文献
132.
Edward R. Westrick MS Allan P. Shapiro PhD Peter E. Nathan PhD John Brick PhD 《Alcoholism, clinical and experimental research》1988,12(4):531-533
The present study demonstrates that alcohol-induced memory impairment can be attenuated by pretreatment with an oral tryptophan supplementation. These results provide support for the role of a brain serotonin deficit in this impairment and highlight the impact a dietary manipulation can have on a complex behavioral process. 相似文献
133.
Tissue-specific regulation of pyroglutamate aminopeptidase II activity by thyroid hormones 总被引:2,自引:0,他引:2
Among the enzymes capable of degrading thyrotropin-releasing hormone (TRH) in vitro, two pyroglutamate aminopeptidases (PGA) are specific for TRH: thyroliberinase, a seric enzyme and PGAII, a membrane-bound peptidase. The effect of thyroid hormone status on the activity of these enzymes was evaluated in serum and various tissues. Only in adenohypophysis, triiodothyronine treatment increased PGAII to 376% of control; hypothyroidism produced the reverse effect (decrease to 23% of control). As previously reported, similar changes were observed for thyroliberinase. TRH degradation at the adenohypophysis level may participate in the negative feedback control of thyroid hormones. 相似文献
134.
A novel hybridoma antibody (PASE/4LJ) to human prostatic acid phosphatase suitable for immunohistochemistry 总被引:2,自引:0,他引:2
A M Haines S E Larkin A P Richardson R W Stirling E Heyderman 《British journal of cancer》1989,60(6):887-892
A murine monoclonal antibody PASE/4LJ to prostatic acid phosphatase (PAP) was used to immunostain a wide variety of sections of benign and malignant tissues (654 blocks). Non-neoplastic adult and fetal prostatic glands, primary and metastatic prostatic carcinomas, and scattered cells in prostatic and penile urethra were positive. Rat, dog and rabbit prostates were negative. Nine of 400 tumours of non-prostatic origin showed some positivity: 6/36 carcinoids, 1/9 islet cell tumours, 1/55 ovarian adenocarcinomas (serous) and one carcinosarcoma of the lung (epithelial portion). Positive staining was seen in islet cells in 4/5 specimens of normal pancreas, and in 4/9 blocks of normal pancreas surrounding a pancreatic tumour. Loops of Henle, maculae densae, and distal tubules in 10/10 fetal and 2/9 adult kidneys were also positive, with proximal tubules and collecting ducts negative. All other 159 blocks of non-neoplastic adult and fetal tissues were negative. The antibody was also affinity purified from ascitic fluid, and shown not to inhibit the enzyme activity of prostatic acid phosphatase. 相似文献
135.
R Rosso F Boccardo F Brema M R Sertoli D Amoroso G Bertelli P Pronzato 《Anticancer research》1989,9(4):1153-1156
131 patients with resectable, node-positive breast cancer were treated at the National Institute for Cancer Research of Genoa, Italy with a systemic adjuvant regimen based on 14 cycles of chemotherapy, immunostimulation with levamisole, and--for postmenopausal patients--hormone therapy with tamoxifen. The present evaluation is performed eleven years after the admission of the first patient: so far, 75 patients (57.3%) have relapsed and 52 (39.7%) have died. An analysis of prognostic factors for relapse and death shows that the number of positive axillary lymph nodes and the dimension of the primary tumor are significantly associated with survival and relapse-free survival, while age and menopausal status are not. 相似文献
136.
P. THOMPSON F. INGLIS D. FINDLAY J. GILCHRIST M. E. T. MCMURDO 《Aging & mental health》1997,1(2):181-183
The Dundee Memory Clinic was established in 1991. This paper reviews the diagnosis of the first 150 attenders and compares the findings with those of other memory clinics. 相似文献
137.
There has been a remarkable change in the scenario of therapeutic apheresis in the last 14 years in India. The crude method of manual removal of blood followed by separation of plasma by gravity, keeping it in the bottle for a long time, has now been totally replaced by plasmapheresis, centrifugation, membrane filtration, and immunoadsorption techniques. The indications for use have also changed from a list of limited indications in the beginning to include all immune complex disorders. The clinical beneficiaries have also increased from blood bankers to nephrologists and immunologists in addition to oncologists. Efforts are now underway with the help of the Indian Society for Apheresis (founded in 1985) to popularize the newer methods of cryofiltration, photopheresis and heparin extracorporeal low-density lipoprotein (HELP) and DALI apheresis systems besides the specialized techniques of immunoadsorption using filters, columns, or ligands. This is suggestive of a positive trend for the treatment of immune complex disorders. 相似文献
138.
139.
140.
Macrophage NRAMP1 and its role in resistance to microbial infections 总被引:12,自引:0,他引:12