全文获取类型
收费全文 | 9585篇 |
免费 | 395篇 |
国内免费 | 53篇 |
专业分类
耳鼻咽喉 | 148篇 |
儿科学 | 127篇 |
妇产科学 | 119篇 |
基础医学 | 1234篇 |
口腔科学 | 223篇 |
临床医学 | 503篇 |
内科学 | 2363篇 |
皮肤病学 | 191篇 |
神经病学 | 810篇 |
特种医学 | 349篇 |
外科学 | 1613篇 |
综合类 | 42篇 |
预防医学 | 260篇 |
眼科学 | 158篇 |
药学 | 587篇 |
中国医学 | 20篇 |
肿瘤学 | 1286篇 |
出版年
2023年 | 48篇 |
2022年 | 122篇 |
2021年 | 178篇 |
2020年 | 88篇 |
2019年 | 128篇 |
2018年 | 149篇 |
2017年 | 123篇 |
2016年 | 160篇 |
2015年 | 153篇 |
2014年 | 277篇 |
2013年 | 303篇 |
2012年 | 468篇 |
2011年 | 493篇 |
2010年 | 330篇 |
2009年 | 263篇 |
2008年 | 420篇 |
2007年 | 536篇 |
2006年 | 547篇 |
2005年 | 532篇 |
2004年 | 505篇 |
2003年 | 502篇 |
2002年 | 479篇 |
2001年 | 258篇 |
2000年 | 241篇 |
1999年 | 234篇 |
1998年 | 139篇 |
1997年 | 133篇 |
1996年 | 121篇 |
1995年 | 88篇 |
1994年 | 82篇 |
1993年 | 81篇 |
1992年 | 191篇 |
1991年 | 171篇 |
1990年 | 160篇 |
1989年 | 169篇 |
1988年 | 130篇 |
1987年 | 138篇 |
1986年 | 97篇 |
1985年 | 93篇 |
1984年 | 79篇 |
1983年 | 77篇 |
1982年 | 41篇 |
1981年 | 38篇 |
1980年 | 30篇 |
1979年 | 61篇 |
1978年 | 47篇 |
1977年 | 41篇 |
1975年 | 33篇 |
1973年 | 28篇 |
1970年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
2.
H Ogawa T Nishikawa S Fukushima S Sasagawa 《Nihon eiseigaku zasshi. Japanese journal of hygiene》1989,44(4):911-920
Recently, food intake in Japan has been characterized by an increase in fat intake, especially animal-fat intake and the maintenance of excess salt (sodium chloride) intake. It is generally accepted that the increase in fat intake is closely related to atherosclerosis, and excess salt intake is a high risk factor for the development of hypertension and cerebrovascular lesions. So far, in almost all reports, the increase in fat intake and excess salt intake have been studied independently, and there have been few reports on the combined effects of these two factors. Taking the above things into consideration, it would seem to be very interesting to investigate the effect of excess salt intake on lipid metabolism. In this paper, we studied the effects of excess salt intake on lipoprotein and apolipoprotein metabolisms, using stroke-prone spontaneously hypertensive rats (SHRSP) and normotensive Kyo: Wistar rats (WKY) as model animals. The results obtained were as follows: A significant increase in the concentration of serum total cholesterol (TC) was observed in SHRSP and WKY, when the rats were given a regular diet (CE-2, Clea Japan Inc.) and 1% sodium chloride solution (1% NaCl) as drinking water for 4 weeks. This was accompanied by a tendency toward increases in the concentrations of serum apolipoproteins in both strains. These results suggest that excess salt intake could accelerate the production of serum total lipoproteins in SHRSP and WKY, when the rats are fed a regular diet. Next, 1% NaCl and a high-fat and high-cholesterol diet (HFC diet) were simultaneously given to SHRSP and WKY for 6 weeks. The effects of simultaneous administration on lipoprotein and apolipoprotein metabolisms were compared with those of HFC feeding. One percent NaCl did not markedly affect hypercholesterolemia in WKY, while it induced more marked hypercholesterolemia in SHRSP that was associated with extreme elevations of serum TC and the atherogenic index (A.I.). This deleterious effect of 1% NaCl in SHRSP was due to drastic elevations of cholesterol contents in the very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL) and low density lipoprotein (LDL) fractions. This was also associated with marked increases in apo B contents in the VLDL, IDL and LDL fractions and significant increases in apo E contents in the VLDL and IDL fractions. These results indicate that 1% NaCl induced much larger increases in serum atherogenic beta-lipoproteins in SHRSP.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
3.
Jong Il Kim Takeshi Tsujino Yoshio Fujioka Komei Saito Mitsuhiro Yokoyama 《Hypertension research》2003,26(4):307-313
We examined cellular membrane fatty acid composition and insulin sensitivity in patients with mild essential hypertension and hyperlipidemia, and investigated whether bezafibrate, a lipid-lowering drug, could improve elevated blood pressure and insulin sensitivity in these subjects by ameliorating cellular membrane fatty acid composition. Twenty-seven subjects were recruited. Twelve men with mild essential hypertension [systolic blood pressure (SBP) between 140 mmHg and 160 mmHg] and hypertriglyceridemia (plasma triglyceride concentration over 150 mg/dl) were designated the HL group. Fifteen men with mild essential hypertension and normotriglyceridemia (plasma triglyceride concentration below 150 mg/dl) were designated the NL group. Subjects in the HL group were given bezafibrate 400 mg/dl and those in the NL group were given placebo for 3 months. Bezafibrate significantly reduced SBP (140 +/- 2.6 to 131.8 +/- 2.6 mmHg, mean +/- SEM), diastolic blood pressure (DBP) (87.8 +/- 2.0 to 82.8 +/- 2.6 mmHg), fasting plasma triglyceride concentration (225.5 +/- 23.5 to 102.9 +/- 10.9 mg/dl), fasting plasma insulin concentration (9.6 +/- 0.8 to 7.1 +/- 0.8 microU/ml), and homeostasis model assessment scores (HOMA-R, 2.4 +/- 0.2 to 1.7 +/- 0.2), and significantly improved the insulin sensitivity index (56.0 +/- 3.0 to 70.7 +/- 4.8 mg x l2/mmol x mU x min) in the HL group. Regarding erythrocyte membrane fatty acid composition, bezafibrate reduced the percentages of saturated fatty acids (SFA) and increased the percentage of polyunsaturated fatty acids (PUFA). Plasma triglyceride concentrations were positively correlated with HOMA-R (r = 0.50, p < 0.01) and SFA (r = 0.39, p < 0.05), and negatively correlated with PUFA (r = -0.45, p < 0.05) before administration of placebo or bezafibrate. In conclusion, an improvement of hyperlipidemia by bezafibrate may be attributed to reduction of blood pressure and amelioration of insulin sensitivity. Abnormalities in membrane lipid composition may play an important role in these metabolic disorders. 相似文献
4.
M A Shibata M Kagawa M Kawabe A Hagiwara S Fukushima 《Teratogenesis, carcinogenesis, and mutagenesis》1991,11(6):305-316
Promoting effects of Na or K phosphate salts on rat two-stage bladder carcinogenesis were compared. Animals were treated with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 4 weeks and thereafter received 1.4% Na3PO4, 2.0% NaH2PO4, 1.0% K3PO4, or 2.5% KH2PO4, these dietary concentrations being selected because they result in approximately equal levels of Na+ and K+ in the urine, equivalent to moderate natriuresis or kaluresis in comparison with our previous data. Treatment with Na3PO4 or K3PO4 induced significant increase in urinary pH compared with control values, whereas urinary pH in the NaH2PO4 and KH2PO4 groups was comparable to control values. With regard to preneoplastic lesion development, both incidences and multiplicity were significantly increased in the groups given Na3PO4 or K3PO4 compared with both controls and NaH2PO4 or KH2PO4 groups, respectively. Furthermore, treatment with Na3PO4 significantly increased multiplicity of papillomas, accompanied by a tendency to increased incidence. No statistically significant difference in promoting potential between Na3PO4 and K3PO4 groups was evident. The present results thus suggest that tumor promotion under conditions of moderate natriuresis or kaluresis depends primarily on high urinary pH. 相似文献
5.
Triphenyl phosphite (TPP), which is widely used in the chemical industry, is known to produce delayed neurotoxicity in some experimental animals. The effects of aging on the susceptibility to TPP, its disposition and pharmacokinetics, and its in vitro degradation by liver homogenate were studied in chickens. Chickens aged 60 days or less at administration were not affected, but 10 of 15 chickens aged 90 to 180 days developed ataxia 10 to 12 days after the intravenous injection of TPP (50 mg/kg). TPP clearance from the blood and most of the tissues examined was faster in 45-day-old chickens than in 135-day-old chickens. The biological half-life of TPP in the blood was 23.2 min. in the younger group and 30.5 min. in the older group. In the in vitro experiment, the initial TPP concentration of 1.6 x 10(-5) M fell to less than half this level within 60 min. during incubation with liver homogenates from 45-day-old chickens, whereas with homogenates from 135-day-old chickens the level remained high. These results suggested that the age-specific susceptibility to TPP was related to the differences of the tissue load, which derived in part from differing levels of metabolic activity in the liver. 相似文献
6.
Nobutaka Eiraku Shinji Ijichi Shinji Yashiki Mitsuhiro Osame Shunro Sonoda 《Journal of neuroimmunology》1992,37(3):223-228
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality. 相似文献
7.
Akira Fukushima 《Psychiatry and clinical neurosciences》1994,48(Z1):1-4
Abstract: Historical changes in forensic psychiatric evaluation on criminal responsibility and proceedings in psychopathological findings of amphetamine psychosis are reviewed at first. The classification of amphetamine related mental disorders are proposed in 6 types. Among them, the clinical characteristics and psychopathological features of “Anxiety-situational reaction type” (Fukushima) are described. According to some reasonable grounds, offenders diagnosed as anxiety-situational reaction type should be evaluated as diminished responsibility in place of irresponsibility. Finally, two cases of murder committed under the influence of amphetamine, are reported in detail. 相似文献
8.
N Suzuki Y Arai Y Miyamoto N Isokane N Fukushima Y Sano 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(12):1630-1637
A 23-year-old male with bronchial asthma developed eosinophilia (eosinophils greater than 2,000/mm3) and was observed at our hospital. After using a prescribed indomethacin suppository for fever at home, he experienced an attack of acute chest pain and severe dyspnea. He suffered cardiac arrest while being transferred to the ward. After resuscitation, he was diagnosed as having acute myocardial infarction on the basis of electrocardiographic and ultrasonic cardiographic findings, and marked elevation of serum concentrations of myocardial enzymes. Thereafter, he often complained of precordial pain and abdominal pain. When he was administered an analgesic in another hospital, he developed severe precordial pain, and marked ST elevation was recorded on the electrocardiogram. Coronary angiography revealed no stenosis nor atherosclerotic changes, suggesting that severe spasm of the coronary arteries and direct myocardial injury by eosinophils were the causes of the myocardial infarction-like symptoms and angina pectoris-like attacks. He was diagnosed as having Churg-Strauss syndrome (allergic granulomatous angiitis) on the basis of the clinical findings; skin biopsy and transbronchial lung biopsy findings were consistent with the diagnosis. Following steroid administration, his angina-like attacks and abdominal pain ceased. This patient developed two episodes of acute cardiovascular symptoms upon administration of antipyretic analgesics. This suggests that in cases of Churg-Strauss syndrome with aspirin-induced asthma, physicians must be aware of the cardiovascular complications, and such drugs should be administered with caution. 相似文献
9.
Proteins from 21 cerebrospinal fluid (CSF) samples (14 derived from neurological cases and 7 from normal individuals) and 15 serum samples (11 from neurological cases and 4 from normal individuals) were analyzed by two-dimensional electrophoresis. Protein mapping revealed a very acidic protein (Ac-P) at about pH 3.5 in the 71% of CSF samples from neurological cases. However, no serum sample contained Ac-P. Ac-P was isolated and purified, and determined to be a glycoprotein containing a large amount of carbohydrate, with molecular weight 42,000 and isoelectric point 2.7-3.3. The amino acid composition of Ac-P was consistent with alpha 1-acid glycoprotein (AGP), and Ac-P was responsive to a commercial anti-AGP antiserum in the radial immunodiffusion test. The known polymorphism of AGP suggests some differences in physicochemical properties such as molecular weight and isoelectric point between AGP in serum and in CSF. Quantitative analysis of Ac-P (AGP) and total protein levels in CSF showed a partial interdependence. Ac-P may be a useful marker for detecting a pathological conditions of the central nervous system. 相似文献
10.
Invasion of the skull base by carcinomas: histopathologically evidenced findings with CT and MRI 总被引:3,自引:0,他引:3
Haruhiko Ishida Mitsuhiro Mohri Mutsuo Amatsu 《European archives of oto-rhino-laryngology》2002,259(10):535-539
The depth and extent of the invasion of the skull base by a tumor are the most critical information for successful en bloc resection of the tumor. The only means available for the evaluation of these factors are CT or MRI images. In order to clarify the ability of these imaging modes to delineate the invasion of the skull base, preoperative images of ten patients who underwent en bloc resection of skull base tumors at Kobe University Hospital were compared with the histopathological findings of the resected specimens. CT proved to be superior to MRI for evaluating bone destruction of the skull base. On the other hand, MRI provided more useful information about intracranial invasion than CT. As a hypertrophic linear shadow on Gd-enhanced MRI represented dural invasion or thickened dura mater adjacent to the tumor, this technique should be taken into consideration to determine the dural resection. We concluded that preoperative evaluation of the depth of skull base invasion by both CT and Gd-enhanced MRI is essential for planning complete tumor resection. 相似文献