全文获取类型
收费全文 | 9406篇 |
免费 | 403篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 216篇 |
妇产科学 | 135篇 |
基础医学 | 1055篇 |
口腔科学 | 217篇 |
临床医学 | 511篇 |
内科学 | 2158篇 |
皮肤病学 | 122篇 |
神经病学 | 888篇 |
特种医学 | 273篇 |
外科学 | 1604篇 |
综合类 | 43篇 |
预防医学 | 254篇 |
眼科学 | 223篇 |
药学 | 759篇 |
中国医学 | 24篇 |
肿瘤学 | 1291篇 |
出版年
2023年 | 54篇 |
2022年 | 88篇 |
2021年 | 150篇 |
2020年 | 90篇 |
2019年 | 134篇 |
2018年 | 179篇 |
2017年 | 122篇 |
2016年 | 151篇 |
2015年 | 151篇 |
2014年 | 200篇 |
2013年 | 255篇 |
2012年 | 385篇 |
2011年 | 417篇 |
2010年 | 256篇 |
2009年 | 212篇 |
2008年 | 449篇 |
2007年 | 409篇 |
2006年 | 485篇 |
2005年 | 533篇 |
2004年 | 541篇 |
2003年 | 534篇 |
2002年 | 525篇 |
2001年 | 242篇 |
2000年 | 261篇 |
1999年 | 251篇 |
1998年 | 167篇 |
1997年 | 119篇 |
1996年 | 123篇 |
1995年 | 104篇 |
1994年 | 99篇 |
1993年 | 90篇 |
1992年 | 210篇 |
1991年 | 191篇 |
1990年 | 183篇 |
1989年 | 159篇 |
1988年 | 159篇 |
1987年 | 127篇 |
1986年 | 126篇 |
1985年 | 110篇 |
1984年 | 84篇 |
1983年 | 98篇 |
1982年 | 47篇 |
1981年 | 40篇 |
1980年 | 34篇 |
1979年 | 57篇 |
1977年 | 46篇 |
1976年 | 35篇 |
1973年 | 36篇 |
1972年 | 41篇 |
1971年 | 34篇 |
排序方式: 共有9844条查询结果,搜索用时 781 毫秒
1.
Mayuko Kinoshita Haruka Kaneko Lizu Liu Masashi Nagao Ryo Sadatsuki 《Modern rheumatology / the Japan Rheumatism Association》2019,29(1):157-164
Objectives: To examine the factors associated with increase in lumbar spine bone mineral density (LS-BMD) by bisphosphonates (BPs) with active vitamin D analog (aVD).Methods: Two independent postmenopausal osteoporotic patients treated by BPs with aVD for 24 months (Study 1: n?=?93, Study 2: n?=?99) were retrospectively analyzed.Results: In Study 1, LS-BMD of the patients significantly increased for 24 m (5.4%, p?.001). A multiple regression analysis among baseline characteristics revealed that serum calcium (sCa: 8.5–10.5?mg/dL) was associated with an increased LS-BMD by treatment (r2: 0.088, p?=?.02). While average sCa of the patients was 9.2?mg/dL before treatment, it increased time-dependently to 9.6?mg/dL for 24 m by treatment. As each patient had their LS-BMD five times during the study, there were four instances of %LS-BMD in each patient, resulting in 372 instances of %LS-BMD in Study 1. The smallest Akaike’s information criterion value for the most appropriate cut-off levels of sCa for %LS-BMD by treatment every 6 m was 9.3?mg/dL. The %LS-BMD by treatment for 6 m during 24 m period in patients with sCa ≥9.3?mg/dL (1.5%) was significantly higher than that in patients with sCa <9.3?mg/dL (0.8%, p?=?.038). The results of Study 2 were similar to those of Study 1, confirming the phenomena observed.Conclusion: sCa was associated with an increased LS-BMD by BPs with aVD. 相似文献
2.
Yosuke Homma Takashi Shiga Hiraku Funakoshi Dai Miyazaki Atsushi Sakurai Yoshio Tahara Ken Nagao Naohiro Yonemoto Arino Yaguchi Naoto Morimura 《The American journal of emergency medicine》2019,37(2):241-248
Objective
This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.Methods
This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.Results
Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96–0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92–0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.Conclusions
While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed. 相似文献3.
Tetsuo Shoji Yoshiki Nishizawa 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2006,10(Z1):S27-S33
Abstract: The risk of cardiovascular death is high in hemodialysis (HD) patients, and thickening, stiffening and calcification of the arterial wall have been shown as its predictive factors. Activated vitamin D preparations are used for the treatment of secondary hyperparathyroidism in HD patients, but as they increase serum phosphate and calcium concentrations, there is a concern that they promote vascular calcification and, consequently, exacerbate the outcomes. In this article, the effects of vitamin D therapy on survival, cardiac function, arteriosclerosis, immunity, and inflammation are evaluated by reviewing the literature. In HD patients, the risk of death (particularly cardiovascular death) is significantly lower in those treated than in those not treated with vitamin D. Moreover, activated vitamin D improves cardiac function and alleviates cardiac hypertrophy in HD patients. Experimental data in cultured macrophages, vascular smooth muscle cells, and vascular endothelial cells suggest that it has antiatherosclerotic effects. In vivo, the administration of vitamin D improves immune functions and normalizes inflammatory reactions. In HD patients, vascular calcification is related to the dose of calcium carbonate, but its relationship with the administration of vitamin D is not significant. These observations suggest that, contrary to the general concerns, activated vitamin D exerts favorable effects on the cardiovascular system in HD patients as long as it is used in appropriate clinical doses. 相似文献
4.
Ritsuko K. Pooh Yoshihiko Nagao Kyonghon Pooh 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(3):123-134
Neurosonography by advanced transvaginal sonography has revealed normal and abnormal intracranial morphology. Transvaginal 3D sonography demonstrates bony structures, multiplanar analysis of inside detailed morphology, tomographic ultrasound imaging in any cutting sections, 3D sonoangiography and volume calculation of ventricles and/or intracranial lesions. Longitudinal assessment of normal and abnormal CNS development is easy by serial scanning. However, the transvaginal approach has several limitations due to its observation by use of a high-frequency transducer from the fetal parietal region. Evaluation of the brainstem and posterior fossa, which are located far from the parietal ultrasound windows of the anterior fontanelle or sagittal suture, is sometimes hard by transvaginal sonography. Visualization of bilateral temporal areas is getting difficult with advanced gestational weeks because of bilateral acoustic shadows due to ossification of parietal bones. Demonstration of frontal/occipital areas is sometimes impossible in late pregnancy due to scan-angle limitation of the transvaginal transducer. From our experiences, the main difference between transvaginal 3D ultrasound and MRI is demonstration of the whole gyral and sulcal formation and brainstem in the late second and third trimesters. Although MRI is a useful modality which can compensate for pitfalls of transvaginal 3D ultrasound, 3D ultrasound is sometimes superior to MRI in detecting cysts in cyst and intracranial calcification. Transvaginal 3D ultrasound is much superior to MRI in detecting bony structures and angioarchitectonics and in volumetric assessment. Regarding objective and accurate prenatal diagnosis, any less-invasive modalities can be used. After considering each advantage and disadvantage of transvaginal 3D ultrasound and MR imaging, it is suggested to use the different technologies according to what is to be detected and evaluated. 相似文献
5.
Y Nishizawa T Shoji S Tanaka M Yamashita A Morita M Emoto T Tabata T Inoue H Morii 《American journal of kidney diseases》1998,31(4):655-661
Leptin is a newly found hormone secreted by adipocytes that regulates food intake, thermogenesis, and body fat. We measured plasma leptin levels in 103 patients with chronic renal failure treated by hemodialysis and 167 age- and gender-matched healthy control subjects to examine the impact of renal failure on plasma leptin levels and the influence of leptin on body composition measured by dual-energy X-ray absorptiometry. Hemodialysis patients showed a significant decrease in both body fat mass and lean body mass compared with those of the control subjects. Plasma leptin was significantly elevated in the hemodialysis group over the controls. In both groups, leptin was higher in female than male subjects, and it correlated positively with percent body fat. The subjects were divided into six categories according to percent body fat, and plasma leptin levels were compared between the two groups in the same category. Leptin of hemodialysis patients was significantly higher than that of the control subjects in the percent body fat categories of 30 or greater, whereas there was no statistically significant difference in leptin concentrations in the lower percent body fat categories. This was also true in the comparison in each gender, and leptin levels in female subjects showed a more remarkable difference between the hemodialysis and control groups in obese categories. Multiple regression analysis in all subjects indicated that plasma leptin levels were independently affected by percent body fat, plasma insulin concentration, gender, and renal failure. The positive impact of renal failure on leptin remained significant in the subjects with percent body fat of 30 or greater in the multiple regression model, whereas it was no longer significant in the remaining lean subjects. In multiple regression analysis of factors affecting fat mass index and lean mass index, leptin level was selectively associated with fat mass index, but not with lean mass index, regardless of percent body fat ranges. These results indicate that renal failure is an important factor affecting plasma leptin levels, especially in obese female subjects, and that hyperleptinemia was closely related to fat mass but not to lean body mass in hemodialysis patients. 相似文献
6.
Shoji Kubo Hiroaki Kinoshita Kazuhiro Hirohashi Takatsugu Yamamoto 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(1):85-89
A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in
the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular
cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion
and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor
became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy
(S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of
changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma. 相似文献
7.
A 67-year-old woman, who presented polyneuropathy, pleural effusion, ascites and sclerosing changes in the ribs, was admitted to our hospital on June 17, 1987. On admission, cerebrospinal examination showed a marked protein-cell dissociation and a delay in nerve conduction velocity. Bence-Jones protein was detected in urine, and the immunohistochemical study of biopsied bone marrow of the rib revealed lambda-chain positive plasmacytoma. Serum immunoelectrophoresis, however, showed no monoclonal gamma-globulinemia. From the findings described above, she was diagnosed as having Crow-Fukase syndrome associated with lambda-type light chain disease. Even with a therapy by prednisolone, platelet counts progressively declined to 10,000/ml3. Bone marrow aspiration showed normal number of megakaryocytes. Since platelet-associated IgG was increased to 452 ng/1.0 x 10(8) plt, a diagnosis of autoimmune thrombocytopenia was considered. Melphalan and cyclophosphamide to plasmacytoma resulted in a marked improvement of platelets. In addition, the level of platelet-associated IgG returned to normal range. Polyneuropathy, however, didn't respond to those therapies. It was suggested that both Crow-Fukase syndrome and thrombocytopenia were closely concerned with plasmacytoma but developed in a different manner. 相似文献
8.
Yuki Izawa Masanori Yoshizumi Keisuke Ishizawa Yoshiko Fujita Shuji Kondo Shoji Kagami Kazuyoshi Kawazoe Koichiro Tsuchiya Shuhei Tomita Toshiaki Tamaki 《Hypertension research》2007,30(11):1107-1117
Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling. 相似文献
9.
Kazuyoshi Kataoka Katsuo Furukawa Kohichi Nagao Nobuhisa Ishii Hiromichi Tsuru 《International journal of urology》2007,14(8):764-768
AIM: To investigate the participation of adenosine receptors in the adenosine 5'-triphosphate (ATP)-induced relaxation in the corpus cavernosum penis (CCP) of rabbits. METHODS: The ATP-induced relaxation was assessed on the noradrenaline precontracted CCP of rabbits in the presence and absence of 8-(3-chlorostyryl)caffeine (CSC); an adenosine A(2A) receptor antagonist; alloxazine and MRS1754; adenosine A(2B) receptor antagonists; and ARL67156, an inhibitor of ecto-nucleoside triphosphate diphosphohydrolases. RESULTS: Adenosine and ATP relaxed the noradrenaline precontracted CCP of rabbits in a concentration-dependent manner. The adenosine- and ATP-induced relaxations were suppressed by alloxazine and MRS1754, but not by 8-(3-chlorostyryl)caffeine. ARL67156 potentiated the ATP-induced relaxation but not the adenosine-induced one. MRS1754 suppressed the ATP-induced relaxation potentiated by ARL67156. CONCLUSIONS: The above results suggest that, in the CCP of rabbits, the adenosine receptor mediating adenosine-induced relaxation is of the A(2B) receptor and the ATP directly causes relaxation through the A(2B) receptor on the CCP. 相似文献
10.
Histamine-type 2 antagonists (H2-blockers) as represented by cimentidine have been shown to adversely affect renal allograft function, particularly when coadministered
with cyclosporine, currently a major immunosuppressant. To determine whether or not a newer and more powerful H2-blocker, famotidine, would produce similar adverse effects, we assessed seven cyclosporine-treated renal allograft recipients
with regard to changes in their renal function on or off the H2-blocker over a one-week period. Neither the administration nor withdrawal of famotidine (20–40 mg/day) resulted in any significant
changes in serum creatine, BUN, urine output or cyclosporine trough levels, suggesting that famotidine can be safely administered
as an H2-blocker to cyclosporine-treated renal allograft recipients. 相似文献