全文获取类型
收费全文 | 6379篇 |
免费 | 258篇 |
国内免费 | 27篇 |
专业分类
耳鼻咽喉 | 35篇 |
儿科学 | 72篇 |
妇产科学 | 31篇 |
基础医学 | 677篇 |
口腔科学 | 120篇 |
临床医学 | 356篇 |
内科学 | 1986篇 |
皮肤病学 | 40篇 |
神经病学 | 463篇 |
特种医学 | 344篇 |
外科学 | 1179篇 |
综合类 | 23篇 |
预防医学 | 121篇 |
眼科学 | 20篇 |
药学 | 301篇 |
中国医学 | 11篇 |
肿瘤学 | 885篇 |
出版年
2023年 | 52篇 |
2022年 | 109篇 |
2021年 | 187篇 |
2020年 | 91篇 |
2019年 | 117篇 |
2018年 | 162篇 |
2017年 | 121篇 |
2016年 | 174篇 |
2015年 | 173篇 |
2014年 | 206篇 |
2013年 | 251篇 |
2012年 | 391篇 |
2011年 | 438篇 |
2010年 | 242篇 |
2009年 | 189篇 |
2008年 | 368篇 |
2007年 | 371篇 |
2006年 | 382篇 |
2005年 | 369篇 |
2004年 | 385篇 |
2003年 | 375篇 |
2002年 | 352篇 |
2001年 | 89篇 |
2000年 | 82篇 |
1999年 | 98篇 |
1998年 | 85篇 |
1997年 | 75篇 |
1996年 | 68篇 |
1995年 | 69篇 |
1994年 | 36篇 |
1993年 | 57篇 |
1992年 | 65篇 |
1991年 | 45篇 |
1990年 | 42篇 |
1989年 | 53篇 |
1988年 | 31篇 |
1987年 | 39篇 |
1986年 | 34篇 |
1985年 | 32篇 |
1984年 | 18篇 |
1983年 | 25篇 |
1982年 | 11篇 |
1981年 | 14篇 |
1980年 | 8篇 |
1979年 | 12篇 |
1978年 | 9篇 |
1976年 | 7篇 |
1972年 | 11篇 |
1971年 | 7篇 |
1970年 | 6篇 |
排序方式: 共有6664条查询结果,搜索用时 0 毫秒
41.
Sakai T Tsushima T Kimura D Hatanaka R Yamada Y Fukuda I 《Kyobu geka. The Japanese journal of thoracic surgery》2011,64(5):423-425
A 61-year-old man, who had medical history of hepatitis type C, surgery for malignant melanoma of the lower limb, endoscopic mucosal resection for esophageal cancer, was pointed out a pulmonary nodule in the right middle lobe by surveillance computed tomography after 5 years of surgery for melanoma. Pathology of esophageal cancer was squamous cell carcinoma limited in mucosa without lymphatic nor venous invasion. The nodule gradually enlarged and respiratory endoscopic examination could not establish pathological diagnosis. Thoracoscopy-assisted pulmonary biopsy revealed squamous cell carcinoma, and right middle lobectomy with mediastinal node dissection was performed. Histological examination showed moderately differentiated squamous cell carcinoma without lymph node involvement. The stage of lung cancer was T1N0M0, stage IA. Although 9 months have passed since surgery for lung cancer, recurrence of each malignancy has not been detected. 相似文献
42.
Yukawa H Noguchi H Oishi K Miyazaki T Kitagawa Y Inoue M Hasegawa M Hayashi S 《Cell transplantation》2008,17(1-2):43-50
Adipose tissue-derived stem cells (ASCs) are expected to have clinical applications as well as other stem cells, because ASCs can be obtained safely from adult donors and used in autologous therapies without concern about rejection and the need for immunosuppression. However, the use of gene transfer with Sendai virus (SeV) vectors, which can efficiently introduce foreign genes without toxicity into several cells, with ASCs has not yet been investigated. This study documents on the use of SeV vectors for gene transfer to ASCs. The dose-dependent GFP expression of ASCs transfected with SeV vectors after 48 h of culture at 37 degrees C was first evaluated. Next, the cellular toxicity of ASCs transfected with SeV vectors was verified. In addition, SeV vectors were compared with adenovirus (AdV) vectors. Finally, the time-dependent GFP expression of ASCs transfected with SeV vectors was evaluated. The results showed that transfection of ASCs with SeV vectors results in more efficient expression of transgene (GFP expression) in the ASCs than with AdV vectors after 48 h of culture at 37 degrees C. Moreover, while the transfection of ASCs with AdV vectors at high MOIs was cytotoxic (a lot of transfected cells died) that of ASCs with SeV vectors at high MOIs was not necessarily cytotoxic. In addition, the preservation of multilineage ASCs transfected with SeV was observed. In conclusion, this is the first report describing the successful use of SeV-mediated gene transfer in ASCs, and the results indicate that SeV may thus provide advantages with respect to safety issues in gene therapy. 相似文献
43.
Yamato Y Matsukawa M Yanagitani T Yamazaki K Mizukawa H Nagano A 《Calcified tissue international》2008,82(2):162-169
The mineral component of bone is mainly composed of calcium phosphate, constituting 70% of total bone mass almost entirely
in the form of hydroxyapatite (HAp) crystals. HAp crystals have a hexagonal system and uniaxial elastic anisotropy. The objective
of this study was to investigate the effect of HAp crystallite preference on macroscopic elasticity. Ultrasonic longitudinal
wave velocity and the orientation of HAp crystallites in bovine cortical bone are discussed, considering microstructure, density,
and bone mineral density (BMD). Eighty cube samples of cortical bone were made from two bovine femurs. The orientation of
HAp crystallites was evaluated by integrated intensity ratio of (0002) peak using an X-ray diffractometer. Ultrasonic longitudinal
wave velocity was investigated with a conventional pulse system. The intensity ratio of HAp crystallites and velocity were
measured in three orthogonal directions; most HAp crystallites aligned in the axial direction of the femurs. Our results demonstrate
a linear correlation between velocity and intensity ratio in the axial direction. Significant correlation between velocity
and BMD values was observed; however, the correlation disappeared if we focused on the identical type of microstructure. In
conclusion, differences in microstructure type have an impact on density and BMD, which clearly affects the velocity. In addition,
at the nanoscopic level, HAp crystallites aligned in the axial direction also affected the velocity and anisotropy. 相似文献
44.
Increased uncoupling protein-2 levels in beta-cells are associated with impaired glucose-stimulated insulin secretion: mechanism of action 总被引:22,自引:0,他引:22
Chan CB De Leo D Joseph JW McQuaid TS Ha XF Xu F Tsushima RG Pennefather PS Salapatek AM Wheeler MB 《Diabetes》2001,50(6):1302-1310
In pancreatic beta-cells, glucose metabolism signals insulin secretion by altering the cellular array of messenger molecules. ATP is particularly important, given its role in regulating cation channel activity, exocytosis, and events dependent upon its hydrolysis. Uncoupling protein (UCP)-2 is proposed to catalyze a mitochondrial inner-membrane H(+) leak that bypasses ATP synthase, thereby reducing cellular ATP content. Previously, we showed that overexpression of UCP-2 suppressed glucose-stimulated insulin secretion (GSIS) in isolated islets (1). The aim of this study was to identify downstream consequences of UCP-2 overexpression and to determine whether insufficient insulin secretion in a diabetic model was correlated with increased endogenous UCP-2 expression. In isolated islets from normal rats, the degree to which GSIS was suppressed was inversely correlated with the amount of UCP-2 expression induced. Depolarizing the islets with KCl or inhibiting ATP-dependent K(+) (K(ATP)) channels with glybenclamide elicited similar insulin secretion in control and UCP-2-overexpressing islets. The glucose-stimulated mitochondrial membrane ((m)) hyperpolarization was reduced in beta-cells overexpressing UCP-2. ATP content of UCP-2-induced islets was reduced by 50%, and there was no change in the efflux of Rb(+) at high versus low glucose concentrations, suggesting that low ATP led to reduced glucose-induced depolarization, thereby causing reduced insulin secretion. Sprague-Dawley rats fed a diet with 40% fat for 3 weeks were glucose intolerant, and in vitro insulin secretion at high glucose was only increased 8.5-fold over basal, compared with 28-fold in control rats. Islet UCP-2 mRNA expression was increased twofold. These studies provide further strong evidence that UCP-2 is an important negative regulator of beta-cell insulin secretion and demonstrate that reduced (m) and increased activity of K(ATP) channels are mechanisms by which UCP-2-mediated effects are mediated. These studies also raise the possibility that a pathological upregulation of UCP-2 expression in the prediabetic state could contribute to the loss of glucose responsiveness observed in obesity-related type 2 diabetes in humans. 相似文献
45.
Orbital cavernous hemangiomas (CHs) manifest as slowly developing symptoms indicative of slow growth. The present study investigated the involvement of angiogenic factors and their receptors in the growth of orbital CHs. Surgical specimens of orbital CHs were obtained from nine patients. Formalin-fixed, paraffin-embedded specimens were stained immunohistochemically using antibodies against Ki-67, CD31, alpha-smooth muscle actin (alpha-SMA), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and VEGF receptors (flt-1 and flk-1). CD31 was expressed in the single layer of endothelial cells lining the vascular cavity. The thick vascular walls were positive for alpha-SMA, indicating that the vascular walls were smooth muscle cells. Ki-67 antigen immunostaining was mostly positive in the vascular walls and the staining index ranged from 0% to 6.8% (mean +/- standard deviation, 2.7 +/- 1.9%). VEGF and bFGF immunostaining were positive in all specimens. Flt-1 immunostaining was negative in all specimens, but flk-1 immunostaining was positive in both endothelial cells and smooth muscle cells. These results suggest that both VEGF and its receptor flk-1 are important in the growth of orbital CH. 相似文献
46.
There are two issues in informed consent for colorectal cancer surgery. One is the actual surgical technique. Recently intersphincteric resection (ISR) has been performed to avoid permanent colostomy, although it is not standard procedure. Regarding QOL score, Patients with colostomies do not necessarily have lower quality of life scores than patients who undergo sphincter-preserving surgery because of frequent bowel movements. Lateral lymphadenectomy for lower rectal cancer was standard procedure; however, its indications became limited due to urinary and sexual dysfunction. Preoperative radiotherapy is considered instead of lateral lymphadenectomy, as in the Western concept of the local recurrence of rectal cancer. Now laparoscopic surgery is accepted for stage I colon cancer according to the guidelines of the Japan Society for Cancer of the Colon and Rectum. The other issue is postoperative complications like anastomotic leakage, intestinal obstruction, etc. Frequent bowel movements and urinary and sexual dysfunction should also be explained before rectal cancer surgery. 相似文献
47.
Yutaka Senga Seiichiro Ozono Hayakazu Nakazawa Satoshi Nagamori Ken Marumo Shigeo Horie Tetsuro Onishi Noriomi Miyao Masahiro Nakao Tatsuo Igarashi Tomoyasu Tsushima Michihiko Hasegawa Masaru Murai the Japanese Society of Renal Cancer 《International journal of urology》2007,14(4):284-288
OBJECTIVE: A joint study was undertaken by the Japanese Society of Renal Cancer to investigate the present status of partial nephrectomy in Japan and to speculate about what may be the indications for partial nephrectomy in patients with renal cell carcinoma. METHODS: Data were tabulated for 469 patients from participating medical institutions and various clinical factors were investigated with regard to disease progression (local recurrence and distant metastasis). RESULTS: Disease progression was observed in 21 patients (4.5%). No significant relation to disease progression was observed for sex, laterality, tumor histology, grade and tumor size. Although patients with solitary tumors displayed excellent prognosis irrespective of tumor diameter, patients with multiple tumors displayed a high likelihood of disease progression. Patients older than 77 years old and patients with imperative indication were found to have a poorer prognosis. CONCLUSION: In patients with solitary tumors, partial nephrectomy can be actively performed, even if the patient displays elective indications and the tumor is >4 cm in diameter. In patients displaying multiple tumors with imperative indications, the decision whether to perform partial nephrectomy should be made by the patients and their physicians after considering the impact on curability and the quality of life. 相似文献
48.
Tomohide Hori Shintaro Yagi Yusuke Okamua Taku Iida Kohei Ogawa Hirokazu Tanaka Shoichi Kageyama Hirofumi Hirao Toshiyuki Hata Izumi Kirino Kazuyuki Nagai Toyonari Kubora Kanta Jobara Kosuke Endo Shinji Uemoto 《Surgery today》2014,44(11):2201-2207
An insufficient remnant in extended hepatectomy and small-for-size graft in liver transplantation are critical matters in the field of liver surgery, and reliable and reproducible animal models that can provide clinically relevant and reliable data are needed. We herein describe our detailed surgical procedures for performing 70 % hepatectomy in pigs, and discuss the critical anatomical features, key techniques and pitfalls based on our experience. The porcine liver is divided into four lobes. The right lateral lobe (RLL) accounts for 30 % of the liver volume. Important points, such as selective temporal clamping of the arterial branch, confirmation of a related demarcation line, a two-step process to skeletonize Glisson’s capsules during liver resection and selective ligation of the portal venous branch to the right medial lobe without inducing any subtle injuries to Glisson’s capsules from the RLL to common bile duct, are discussed. 相似文献
49.
Surgical treatment of liver injury with microwave tissue coagulation: an experimental study 总被引:7,自引:0,他引:7
OBJECTIVE: The purpose of this study was to examine whether microwave tissue coagulation (MTC) therapy is capable of stopping bleeding from severe liver injury in pigs. METHODS: Ten pigs (38 +/- 4 kg) underwent a 30-mL/kg isovolemic exchange transfusion with 3% low-molecular-weight dextran to produce dilutional coagulopathy, and then a through-and-through laceration injury measuring approximately 8 cm in length was induced in the right hepatic lobe. Immediately after inflicting the injury, the animals were randomly divided into two groups: Group A (n = 5, MTC was repeated along the liver laceration at intervals of 2.0 cm with manual compression) or Group B (n = 5, the injured lobe was manually compressed without MTC therapy for 1 minute). All animals received lactated Ringer's solution to maintain the mean arterial pressure at 75 mm Hg for 1 hour after the abdominal closure. The intraperitoneal blood loss, mean arterial pressure, volume of lactated Ringer's solution, and hematologic variables were compared between the groups. For further laboratory evaluation, three additional experimental animals were treated with the MTC therapy after inflicting the injury and then were allowed to survive for 14 days. RESULTS: Mean arterial pressure declined from a mean value of 88 +/- 10 mm Hg (range, 75-107 mm Hg) to 62 +/- 3 mm Hg (range, 50-75 mm Hg) after the induction of liver injury. The total blood loss in Group A was 192 +/- 58 g (range, 120-250 g), which was lower (p < 0.01) than that of 448 +/- 138 g (range, 260-650 g) in Group B. The resuscitation fluid volume of Group A animals was 304 +/- 204 mL (range, 100-600 mL), which was smaller (p < 0.01) than that of 1,320 +/- 654 mL (range, 900-2,250 mL) in Group B. At 14 days, all three animals that were treated in the additional study were found to be in good health. Their necropsies showed no evidence of an intrahepatic abscess, hematoma, or biloma. CONCLUSION: MTC therapy was thus found to provide simple, rapid, and definitive hemorrhage control in cases of severe liver injury without the need for reoperation. 相似文献
50.
Nakano M Matsuzaki M Morikawa H Komatsu H 《Hinyokika kiyo. Acta urologica Japonica》2004,50(5):355-357
Postoperative superior mesenteric artery syndrome is a rare complication of left nephrectomy. We treated a case of superior mesenteric artery syndrome that occurred 7 days after radical left nephrectomy for renal cell carcinoma. The patient was a 54-year-old Japanese man who presented with gross hematuria. Abdominal computed tomography showed a 3.8 x 3.8 x 5 cm heterogeneous cystic mass in the left kidney. Transperitoneal left radical nephrectomy was performed because renal cell carcinoma was suspected. The patient resumed oral intake 3 days after surgery, but he began vomiting repeatedly from the 7th day after surgery. Gastroduodenography showed an abrupt vertical linear obstruction of the third portion of the duodenum. Superior mesenteric artery syndrome was diagnosed. Conservative therapy (indwelling nasogastric tube, intravenous hyperalimentation and postural changes) was effective. 相似文献