全文获取类型
收费全文 | 3274篇 |
免费 | 157篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 169篇 |
妇产科学 | 102篇 |
基础医学 | 546篇 |
口腔科学 | 54篇 |
临床医学 | 226篇 |
内科学 | 688篇 |
皮肤病学 | 22篇 |
神经病学 | 169篇 |
特种医学 | 153篇 |
外科学 | 617篇 |
综合类 | 12篇 |
现状与发展 | 1篇 |
预防医学 | 103篇 |
眼科学 | 36篇 |
药学 | 259篇 |
中国医学 | 21篇 |
肿瘤学 | 251篇 |
出版年
2022年 | 38篇 |
2021年 | 53篇 |
2020年 | 25篇 |
2019年 | 37篇 |
2018年 | 52篇 |
2017年 | 35篇 |
2016年 | 43篇 |
2015年 | 45篇 |
2014年 | 74篇 |
2013年 | 73篇 |
2012年 | 137篇 |
2011年 | 155篇 |
2010年 | 66篇 |
2009年 | 70篇 |
2008年 | 152篇 |
2007年 | 134篇 |
2006年 | 168篇 |
2005年 | 180篇 |
2004年 | 171篇 |
2003年 | 217篇 |
2002年 | 200篇 |
2001年 | 123篇 |
2000年 | 98篇 |
1999年 | 84篇 |
1998年 | 41篇 |
1997年 | 22篇 |
1996年 | 28篇 |
1995年 | 24篇 |
1994年 | 23篇 |
1993年 | 28篇 |
1992年 | 70篇 |
1991年 | 71篇 |
1990年 | 77篇 |
1989年 | 70篇 |
1988年 | 63篇 |
1987年 | 67篇 |
1986年 | 52篇 |
1985年 | 61篇 |
1984年 | 21篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 16篇 |
1979年 | 36篇 |
1978年 | 18篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 19篇 |
1974年 | 17篇 |
1973年 | 22篇 |
1971年 | 20篇 |
排序方式: 共有3443条查询结果,搜索用时 0 毫秒
101.
T Funakoshi Y Ueda A Kobayashi H Morikawa M Mochizuki 《Nippon Naibunpi Gakkai zasshi》1990,66(7):688-699
In order to elucidate the roles of Insulin-like Growth Factors (IGF-I, -II) in human pregnancy, the levels of IGF-I and IGF-II, the distribution of binding proteins for IGF-I or IGF-II and profiles of unsaturated somatomedin binding proteins (USBP) were estimated in maternal and cord plasma. IGF-I levels in maternal plasma gradually elevated in late gestation, reaching 304.4 +/- 130.1ng/ml at term, and were significantly higher than those in nonpregnant women (188 +/- 58). IGF-II levels, which were 414.9 +/- 75.4ng/ml in women in the third trimester of gestation, did not produce any remarkable changes in the levels in nonpregnant women (395.9 +/- 72.6). On the other hand, IGF-I in cord plasma also increased according to gestational age, reaching 37.3 +/- 14.6ng/ml at term, but it was significantly lower than that in maternal weight (r = 0.50, p less than 0.005) and relative birth weight (r = 0.41, p less than 0.005). IGF-II in cord plasma showed no significant changes during gestation, however, IGF-II levels in AFD (appropriate for date) newborns delivered at term (203.8 +/- 59.4) were significantly lower than those in maternal plasma. And they had no positive correlations with birth weight and relative birth weight. On Sephadex G150 gel-chromatography of cord plasma from AFD newborns at term, more than 70% of immunoreactive IGF-I in plasma was eluted at 150K region, and 150K USBP could be detected as observed in adult plasma. On the other hand, most of the immunoreactive IGF-II was eluted at 40K region, and 150K USBP was not detected in AFD newborns at term. In adult plasma, most of the immunoreactive IGF-II was eluted at 150K region, but 150K USBP could not be detected. From these results, it is supposed that IGF-I plays an essential role in fetal growth rather than IGF-II. 相似文献
102.
103.
Dr. Takeshi Tomomasa MD Carlo DiLorenzo MD Akihiro Morikawa MD Aliye UC MD Paul E. Hyman MD 《Digestive diseases and sciences》1996,41(11):2195-2203
Antroduodenal manometry has been used to determine the pathophysiology associated with signs and symptoms of gastrointestinal motility disorders. The diagnostic value of antroduodenal manomentry has been limited by the paucity of data from normal children. In this study, we compared antroduodenal manometry findings from 95 patients with symptoms suggesting a gastrointestinal motility disorder to 20 control children. Phase III of the migrating motor complex (MMC) was less frequent in patients (P<0.05), especially in those who required total parenteral nutrition (P<0.001), than in controls. Abnormal migration of phase III and short intervals between phase IIIs were more frequent in patients than in controls (P<0.01 andP<0.05, respectively). During phase II, persistent low-amplitude contractions and sustained tonic-phasic contraction were found only in parenteral-nutrition-dependent children. Short or prolonged duration of phase III, absence of phase I following phase III, tonic contractions during phase III, low amplitude of phase III contractions in a single recording site and clusters of contractions or prolonged propagating contractions during phase II were not more frequent in patients than in controls. We conclude that there are five manometric features having a clear association with pediatric gastrointestinal motility disorders: (1) absence of phase III of the MMC, (2) abnormal migration of phase III, (3) short intervals between phase III episodes, (4) persistent low-amplitude contractions, and (5) sustained tonic-phasic contractions. 相似文献
104.
Saijo M Ami Y Suzaki Y Nagata N Iwata N Hasegawa H Ogata M Fukushi S Mizutani T Iizuka I Sakai K Sata T Kurata T Kurane I Morikawa S 《Japanese journal of infectious diseases》2008,61(2):140-142
Human monkeypox, an infectious disease caused by monkeypox virus (MPXV), is endemic to western and central Africa. A LightCycler quantitative PCR (LC-qPCR) system was developed for the diagnosis of this disease, targeting the A-type inclusion body gene (ATI gene) of MPXV. One naive monkey was infected with MPXV Zr-599 (Congo Basin strain) and one with MPXV Liberia (West African strain). Another three monkeys were immunized with smallpox vaccine on 0, 3, or 7 days, respectively, before infection with MPXV Zr-599. Peripheral blood cell (PBC) and throat swab (TS) specimens were serially collected. The LC-qPCR was validated for the diagnosis of monkeypox using virus isolation. Sequencing of the partial ATI gene revealed the insertion of a unique 453-nucleotide residue in the West African strains but not in the Congo Basin strains. Specific reverse primers for Congo Basin and West African strains were designed based on the unique sequence insertion. The LC-qPCR detected the MPXV genome, but not those of the other orthopoxviruses tested nor the varicella-zoster virus. Both the sensitivity and specificity of the LC-qPCR were over 90% in comparison to virus isolation when TS specimens were tested. Fourteen of the 15 virus isolation-positive PBC specimens showed positive reactions in the assay. Further, most PBC specimens collected from symptomatic monkeys in the later stage of illness showed positive reactions in the assay but negative reaction in virus isolation. It was possible to differentiate between these two groups with the LC-qPCR. Thus, the newly developed LC-qPCR is a useful and reliable diagnostic tool for MPXV infection. 相似文献
105.
106.
107.
J Morikawa T Furukawa H Tanaka Y Tsujimura M Bamba K Kitamura Y Habuchi 《Journal of electrocardiology》1991,24(4):387-394
The serial changes in the QRS loops of vectorcardiograms were investigated following ligation of a branch of the left anterior descending artery (LAD) by the three-dimensional rotation method in 18 dogs. Concave inflections of the QRS loop, defined as "bites," were best delineated when the loop was viewed from a left cranial or right caudal direction. Bites appeared 48 +/- 8 minutes after LAD ligation in all of the dogs, and their development was closely related to the temporal changes in the % sigma R and QRS point score on a standard 12-lead electrocardiogram. Q waves were not observed on the electrocardiograms in 9 dogs. In the remaining 9, they appeared 117 +/- 18 minutes after LAD ligation. The bite duration, area, and amplitude were compared with the anatomical extent of the infarcts. A significant positive correlation was found between bite duration and infarct size. The detection of bites on the three-dimensionally rotated vectorcardiogram appears to have a high sensitivity for anterior myocardial infarction and could potentially become a useful diagnostic tool. 相似文献
108.
Naohiro Makise Teppei Morikawa Taketo Kawai Tohru Nakagawa Haruki Kume Yukio Homma Masashi Fukayama 《International journal of clinical and experimental pathology》2015,8(6):7203-7209
Squamous differentiation is the most common histological variation in urothelial carcinoma (UC). However, the clinical significance of squamous differentiation in upper urinary tract UC is unclear. To investigate the significance of squamous differentiation, hematoxylin and eosin stained slides from 140 patients with upper urinary tract UC who underwent nephroureterectomy were reviewed by a single pathologist and the presence of squamous differentiation was recorded. Squamous differentiation was observed in 23 out of 140 studied cases (16%). Squamous differentiation significantly correlated with several adverse prognostic factors including histological grade 3 tumors, presence of lymphovascular invasion, concomitant carcinoma in situ, advanced tumor stage, and occurrence of lymph node metastasis. The Kaplan-Meier and univariate Cox regression analyses revealed that the presence of squamous differentiation was significantly associated with shorter metastasis-free survival [log-rank P = 0.030; univariate hazard ratio (HR), 2.30; 95% confidence interval (CI), 1.06-4.99], cancer-specific survival (log-rank P = 0.0024; univariate HR 3.34; 95% CI, 1.47-7.85), and overall survival (log-rank P = 0.018; univariate HR 2.39; 95% CI, 1.13-5.06) after nephroureterectomy. However, in multivariate analyses, squamous differentiation was not significantly associated with patient outcomes. These findings suggest that squamous differentiation is associated with disease progression, but is not an independent predictor of a worse prognosis in patients with upper urinary tract UC. 相似文献
109.
110.
Jeffrey J. Pouliot Michael Thomson Mi Xie Joseph Horton John Johnson David Krull Amanda Mathis Yoshio Morikawa Derek Parks Richard Peterson Takashi Shimada Elizabeth Thomas Jessica Vamathevan Stephanie Van Horn Zhiping Xiong Robert Hamatake Andrew J. Peat 《Antimicrobial agents and chemotherapy》2015,59(10):6539-6550
The hepatitis C virus (HCV) NS4B protein is an antiviral therapeutic target for which small-molecule inhibitors have not been shown to exhibit in vivo efficacy. We describe here the in vitro and in vivo antiviral activity of GSK8853, an imidazo[1,2-a]pyrimidine inhibitor that binds NS4B protein. GSK8853 was active against multiple HCV genotypes and developed in vitro resistance mutations in both genotype 1a and genotype 1b replicons localized to the region of NS4B encoding amino acids 94 to 105. A 20-day in vitro treatment of replicons with GSK8853 resulted in a 2-log drop in replicon RNA levels, with no resistance mutation breakthrough. Chimeric replicons containing NS4B sequences matching known virus isolates showed similar responses to a compound with genotype 1a sequences but altered efficacy with genotype 1b sequences, likely corresponding to the presence of known resistance polymorphs in those isolates. In vivo efficacy was tested in a humanized-mouse model of HCV infection, and the results showed a 3-log drop in viral RNA loads over a 7-day period. Analysis of the virus remaining at the end of in vivo treatment revealed resistance mutations encoding amino acid changes that had not been identified by in vitro studies, including NS4B N56I and N99H. Our findings provide an in vivo proof of concept for HCV inhibitors targeting NS4B and demonstrate both the promise and potential pitfalls of developing NS4B inhibitors. 相似文献