全文获取类型
收费全文 | 8456篇 |
免费 | 387篇 |
国内免费 | 69篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 167篇 |
妇产科学 | 83篇 |
基础医学 | 993篇 |
口腔科学 | 128篇 |
临床医学 | 569篇 |
内科学 | 2062篇 |
皮肤病学 | 106篇 |
神经病学 | 623篇 |
特种医学 | 346篇 |
外科学 | 1885篇 |
综合类 | 27篇 |
现状与发展 | 1篇 |
预防医学 | 153篇 |
眼科学 | 110篇 |
药学 | 532篇 |
中国医学 | 8篇 |
肿瘤学 | 1038篇 |
出版年
2023年 | 68篇 |
2022年 | 125篇 |
2021年 | 190篇 |
2020年 | 119篇 |
2019年 | 161篇 |
2018年 | 191篇 |
2017年 | 168篇 |
2016年 | 228篇 |
2015年 | 226篇 |
2014年 | 286篇 |
2013年 | 338篇 |
2012年 | 535篇 |
2011年 | 580篇 |
2010年 | 366篇 |
2009年 | 321篇 |
2008年 | 542篇 |
2007年 | 597篇 |
2006年 | 590篇 |
2005年 | 580篇 |
2004年 | 597篇 |
2003年 | 537篇 |
2002年 | 518篇 |
2001年 | 74篇 |
2000年 | 63篇 |
1999年 | 84篇 |
1998年 | 113篇 |
1997年 | 92篇 |
1996年 | 92篇 |
1995年 | 76篇 |
1994年 | 72篇 |
1993年 | 58篇 |
1992年 | 55篇 |
1991年 | 36篇 |
1990年 | 40篇 |
1989年 | 26篇 |
1988年 | 27篇 |
1987年 | 17篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 14篇 |
1983年 | 11篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1979年 | 5篇 |
1978年 | 13篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1966年 | 2篇 |
1936年 | 2篇 |
排序方式: 共有8912条查询结果,搜索用时 15 毫秒
31.
Masato Ando Yuhzo Nakashima Yutaka Nagata 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1990,13(1-2):33-46
We examined the effect of GM1-ganglioside in combination with cholera toxin B, and synthetic α-sialyl cholesterol (α-SC) on neutral amino acid (tritiated α-aminoisobutyric acid, [3H]AIB) uptake, protein synthesis ([3H]leucine incorporation), and Na+, K+-ATPase activity in isolated superior cervical ganglia (SCG) and nodose ganglia (NG) from adult rats after aerobic incubation, usually for 2 h at 37°C in vitro. Cholera toxin B, that specifically masks the oligosaccharide chain of GM1-ganglioside, antagonized the GM1-induced changes in [3H]AIB uptake, [3H]leucine incorporation, and Na+, K+-ATPase activity almost completely in SCG, but partially in NG. Although cholesterol itself had little effect on either [3H]AIB uptake and Na+, K+-ATPase activity both in SCG and NG, α-SC caused considerable reduction of both amino acid uptake and the transport enzyme activity in each ganglia. However, cholesterol was more effective than α-SC in decreasing [3H]leucine incorporation in either ganglia. Whereas addition of EGTA markedly reduced either GM1-induced or α-SC-induced change in [3H]leucine incorporation into acid-insoluble fraction in both SCG and NG, application of Ca2+ ionophore produced considerable recovery of the protein synthesis from the inhibited level by Ca2+-deprivation. ATP and creatine phosphate contents in SCG were elevated by the presence of GM1 or α-SC, whereas [3H]AIB uptake and Na+, K+-ATPase activity were inhibited, suggesting that utilization for membrane transport was diminished as a result of GM1- or α-SC-induced decrease of ATPase activity. 相似文献
32.
Masato Kochi Shuichi Takaki Jun -ichi Kuratsu Hiroshi Seto Isao Kitamura Yukitaka Ushio 《Journal of neuro-oncology》1994,19(3):239-244
Summary Ventriculolumbar perfusion of methyl 6-[3-(2-chloroethyl)-3-nitrosoureido]-6-deoxy-alpha-D-glucopyranoside (MCNU), a water soluble nitrosourea with log P-0.71, may be efficacious in the treatment of subarachnoid dissemination of malignant glioma. We used 2 dogs to study the neurotoxicity and pharmacokinetics of MCNU. MCNU (1 mg), dissolved in 10 ml of artificial CSF, was administered via the right lateral ventricle during a period of 18 to 42 min and the CSF was drained by lumbar puncture. The perfusion was repeated once a week for 10 consecutive weeks. No neurological and systemic symptoms were noted after perfusion. Histological examination of the brain and spinal cord showed local denudation of the ependyma and local subependymal spongy degeneration and gliosis in the lateral ventricle into which MCNU was administered in one dog and local denudation of the ependyma in the other. When administration was over a period of 21 to 38 min, the MCNU concentration in the lumbar CSF peaked at 11.11 to 50.67 g/ml, in 28 to 78 min. The area under the drug concentration-time curve (AUC) was 1152 g×min/ml on average, significantly larger than that of ACNU. The elimination phase followed linear kinetics and the half-time was 41.1 min on average, significantly longer than that of ACNU. These findings suggest that ventriculolumbar perfusion of MCNU may be effective in the treatment of subarachnoid dissemination of malignant glioma notwithstanding some local histological changes. 相似文献
33.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
34.
Pai RG Jintapakorn W Tanimoto M Cao QL Pandian N Shah PM 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):613-622
Accurate determination of left ventricular (LV) volume has important therapeutic and prognostic implications in patients with cardiac disease. Volume estimations by two-dimensional techniques are not very accurate due to geometric assumptions. OBJECTIVES: To validate LV volume determinations by a new transesophageal three-dimensional echocardiographic technique. We performed three-dimensional reconstruction of the LV using an echo-computed tomographic (CT) technique based on serial pullback parallel slice imaging technique in both in vitro and in vivo settings. Fourteen latex balloons with various sizes (30-235 mL) and shapes (conical, pear shaped, round, elliptical, and aneurysms in various locations) filled with known volumes of water were imaged in a water bath. From the static three-dimensional image, the LV long axis was defined and the LV was sectioned perpendicular to this axis into 2-mm slices. The volume of each slice was calculated with the observer blinded to the actual volume as the product of the slice thickness and the manually traced perimeter of the slice and the LV volume as the sum of the volumes of the slices (Simpson's method). The calculated LV volume closely correlated with the actual volume (r = 0.99, P < 0.0001, calculated volume = 1.06x - 11.3, Deltavolume = -5.7 +/- 10.0 cc). Using the same system, transesophageal echocardiographic (TEE) images of the LV were obtained in 15 patients gated to respiration and ECG. Satisfactory dynamic three-dimensional reconstruction of the LV was possible in ten patients. The three-dimensional LV volumes (systolic and diastolic) using Simpson's method correlated well with those obtained from biplane or multiplane TEE images using the area length method (r = 0.89, p < 0.0001, y = 12.7 + 0.84x, Deltavolume = 1.3 +/- 18.1 cc). The LV major-axis diameters by the two methods showed very close correlations as well (r = 0.86, P < 0.0001, y = 19 + 0.74x, Deltadiameter = 1.0 +/- 7.2 mm). We conclude that three-dimensional LV volume calculation by the echo-CT technique is intrinsically sound, is independent of LV geometry, and with some limitations, is applicable in vivo. (ECHOCARDIOGRAPHY, Volume 13, November 1996) 相似文献
35.
Katsumi Monoo Masato Sageshima Eiko Ito Shigeki Nishihira Kazuo Ishikawa 《Nihon Jibiinkoka Gakkai kaiho》2003,106(3):192-198
In the 22 years between March 1979 and February 2001, we treated 16 patients--10 men and 6 women aged 10-80 years (mean: 44 years)--with mucoepidermoid carcinoma (MEC) of the salivary gland, evaluating them clinically and histopathologically. Tumor sites included 12 at the parotid gland, 3 at the submandibular gland, and 1 at the minor salivary gland. All tumors were graded histopathologically based on the criteria of Goode et al. as follows: low grade (n = 10), intermediate grade (n = 1), and high grade (n = 5). Female gender was associated with low grade MEC and male gender with high grade MEC (P < 0.05). The age at onset in high grade MEC was older than that in low grade MEC (P < 0.005). Lymph-node metastasis was detected in 7 out of the 16 patients (44%) associated significantly with high grade MEC (P < 0.05). Distant metastasis was detected in 4 of 16 patients (25%). Distant metastasis was significantly associated with high grade MEC (P < 0.05). Local recurrence was detected in 3 of 15 patients undergoing surgery (20%). No difference was seen in local recurrence frequency between low and high grade MEC. Survival was calculated with Kaplan-Meier's method. In all 16, 5-year survival was 86% and 10-year survival 75%. Five-year survival in low grade MEC was 100%, whereas that in high grade MEC was 67% (P < 0.05). In MEC of the salivary gland, it was suggested that the histopathological MEC grade evaluated by Goode's criteria significantly correlated with gender, age, lymph-node metastasis, distant metastasis, and 5-year survival. 相似文献
36.
Elevated expression of valosin-containing protein (p97) in hepatocellular carcinoma is correlated with increased incidence of tumor recurrence. 总被引:11,自引:0,他引:11
37.
Treatment of Lethal Midline Granuloma Type Nasal T-Cell Lymphoma 总被引:7,自引:0,他引:7
Kohichi Sakata Masato Hareyama Atushi Ohuchi Mitsuo Sido Hisayasu Nagakura Kazuo Morita Yasuaki Harabuchi Akikatsu Kataura 《Acta oncologica (Stockholm, Sweden)》1997,36(3):307-311
Nasal T-cell lymphoma of the LMG type (LMG-NTL) is characterized by progressive, unrelenting ulceration, and necrosis of the nasal cavity and midline facial tissues. The clinical behavior of this tumor in 16 patients is compared with that of a nasal lymphoma of non-LMG-NTL type (non-LMG-NTL) in 8 patients and a paranasal sinus lymphoma (PSL) in 6 patients. All patients had stage I or II disease. Fourteen of the 16 patients with LMG-NTL received chemotherapy before and/or after radiotherapy. Cause-specific 5-year survival rates for patients with LMG-NTL, non-LMG-NTL, and PSL were 22%, 75%, and 67%, respectively. Seven patients with LMG-NTL, had complete response, although 3 recurred, whereas it was incomplete in 9 patients. The data indicates that it is desirable to deliver 50 Gy or more to achieve in-field control of LMG-NTL. 相似文献
38.
Proton beam therapy for hepatocellular carcinoma: a retrospective review of 162 patients. 总被引:4,自引:0,他引:4
Toshiya Chiba Koichi Tokuuye Yasushi Matsuzaki Shinji Sugahara Yoshimichi Chuganji Kenji Kagei Junichi Shoda Masaharu Hata Masato Abei Hiroshi Igaki Naomi Tanaka Yasuyuki Akine 《Clinical cancer research》2005,11(10):3799-3805
PURPOSE: We present results of patients with hepatocellular carcinoma (HCC) treated with proton beam therapy. EXPERIMENTAL DESIGN: We reviewed 162 patients having 192 HCCs treated from November 1985 to July 1998 by proton beam therapy with or without transarterial embolization and percutaneous ethanol injection. The patients in the present series were considered unsuitable for surgery for various reasons, including hepatic dysfunction, multiple tumors, recurrence after surgical resection, and concomitant illnesses. The median total dose of proton irradiation was 72 Gy in 16 fractions over 29 days. RESULTS: The overall survival rate for all of the 162 patients was 23.5% at 5 years. The local control rate at 5 years was 86.9% for all 192 tumors among the 162 patients. The degree of impairment of hepatic functions attributable to coexisting liver cirrhosis and the number of tumors in the liver significantly affected patient survival. For 50 patients having least impaired hepatic functions and a solitary tumor, the survival rate at 5 years was 53.5%. The patients had very few acute reactions to treatments and a few late sequelae during and after the treatments. CONCLUSIONS: Proton beam therapy for patients with HCC is effective, safe, well tolerable, and repeatable. It is the useful treatment mode for either cure or palliation for patients with HCC irrespective of tumor size, tumor location in the liver, insufficient feeding of the tumor with arteries, presence of vascular invasion, impaired hepatic functions, and coexisting intercurrent diseases. 相似文献
39.
Kayo Sugiyama Subaru Tanabe Hirotaka Watanuki Masato Tochii Yasuhiro Futamura Satoshi Makino Katsuhiko Matsuyama 《Clinical Case Reports》2022,10(5)
Life‐threatening cardiac events may be misdiagnosed as acute aortic dissection because of notable symptom mimicry. We report the case of a 72‐year‐old male patient with presentations presumed to be of aortic origin. However, surgery revealed posterior free‐wall perforation in the left ventricle caused by the occlusion of an obtuse marginal branch. 相似文献
40.
Jonguk Park Koji Hosomi Hitoshi Kawashima Yi-An Chen Attayeb Mohsen Harumi Ohno Kana Konishi Kumpei Tanisawa Masako Kifushi Masato Kogawa Haruko Takeyama Haruka Murakami Tetsuya Kubota Motohiko Miyachi Jun Kunisawa Kenji Mizuguchi 《Nutrients》2022,14(10)
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated to improving health by controlling the gut microbial environment. Probiotics and prebiotics are being developed to support a healthier intestinal environment. However, much work remains to be performed to provide effective solutions to overcome individual differences in the gut microbial community. This study examined the importance of nutrients, other than dietary fiber, on the survival of gut bacteria in high-health-conscious populations. We found that vitamin B1, which is an essential nutrient for humans, had a significant effect on the survival and competition of bacteria in the symbiotic gut microbiota. In particular, sufficient dietary vitamin B1 intake affects the relative abundance of Ruminococcaceae, and these bacteria have proven to require dietary vitamin B1 because they lack the de novo vitamin B1 synthetic pathway. Moreover, we demonstrated that vitamin B1 is involved in the production of butyrate, along with the amount of acetate in the intestinal environment. We established the causality of possible associations and obtained mechanical insight, through in vivo murine experiments and in silico pathway analyses. These findings serve as a reference to support the development of methods to establish optimal intestinal environment conditions for healthy lifestyles. 相似文献