全文获取类型
收费全文 | 9353篇 |
免费 | 494篇 |
国内免费 | 68篇 |
专业分类
耳鼻咽喉 | 58篇 |
儿科学 | 190篇 |
妇产科学 | 106篇 |
基础医学 | 940篇 |
口腔科学 | 180篇 |
临床医学 | 715篇 |
内科学 | 2773篇 |
皮肤病学 | 206篇 |
神经病学 | 682篇 |
特种医学 | 268篇 |
外科学 | 1648篇 |
综合类 | 34篇 |
预防医学 | 235篇 |
眼科学 | 238篇 |
药学 | 462篇 |
1篇 | |
中国医学 | 17篇 |
肿瘤学 | 1162篇 |
出版年
2023年 | 74篇 |
2022年 | 171篇 |
2021年 | 265篇 |
2020年 | 132篇 |
2019年 | 176篇 |
2018年 | 213篇 |
2017年 | 206篇 |
2016年 | 240篇 |
2015年 | 268篇 |
2014年 | 289篇 |
2013年 | 340篇 |
2012年 | 567篇 |
2011年 | 651篇 |
2010年 | 309篇 |
2009年 | 271篇 |
2008年 | 423篇 |
2007年 | 511篇 |
2006年 | 449篇 |
2005年 | 480篇 |
2004年 | 399篇 |
2003年 | 448篇 |
2002年 | 403篇 |
2001年 | 241篇 |
2000年 | 298篇 |
1999年 | 222篇 |
1998年 | 100篇 |
1997年 | 62篇 |
1996年 | 76篇 |
1995年 | 63篇 |
1994年 | 63篇 |
1993年 | 45篇 |
1992年 | 162篇 |
1991年 | 150篇 |
1990年 | 125篇 |
1989年 | 161篇 |
1988年 | 108篇 |
1987年 | 88篇 |
1986年 | 86篇 |
1985年 | 85篇 |
1984年 | 52篇 |
1983年 | 59篇 |
1982年 | 29篇 |
1981年 | 23篇 |
1980年 | 23篇 |
1979年 | 45篇 |
1978年 | 23篇 |
1976年 | 21篇 |
1975年 | 23篇 |
1972年 | 21篇 |
1971年 | 23篇 |
排序方式: 共有9915条查询结果,搜索用时 15 毫秒
101.
Carbonic anhydrase is aberrantly and constitutively expressed in both human and murine erythroleukemia cells. 总被引:1,自引:0,他引:1 下载免费PDF全文
S R Frankel J Walloch R K Hirata M C Bondurant R Villanueva S C Weil 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(15):5175-5179
The levels of the erythrocyte proteins carbonic anhydrase (CA) and hemoglobin (Hb) change coordinately during human ontogeny. To further probe the coordinate gene expression of these two proteins in vitro, we used an immunoblotting technique to measure their levels during erythroid differentiation in normal human and murine erythroid progenitors, in human and murine erythroleukemia cells, and in normal murine erythroid progenitors infected with Friend virus. Levels of CA and Hb seem to gradually increase in normal differentiating stem cells. In contrast, both human and murine erythroleukemia cells show high levels of CA, but not of Hb, prior to induction of differentiation. Friend virus infection of normal murine progenitors appears to stimulate CA synthesis as an initial and integral step in transformation. In addition, both the erythroleukemia cells and the erythroid progenitors transformed with Friend virus seem to contain much higher levels of CA than Hb during the early stages of differentiation. This relationship is in marked contrast to normal erythroid differentiation, in which Hb levels are always higher than CA levels. Thus, neoplastic transformation seems to be associated with aberrant production of CA that does not correspond to a maturation arrest of the normal differentiation sequence. 相似文献
102.
Nishida N Yamashita S Mimori K Sudo T Tanaka F Shibata K Yamamoto H Ishii H Doki Y Mori M 《Annals of surgical oncology》2012,19(9):3065-3071
Purpose
Recent evidence has shown that altered patterns of microRNA (miRNA) expression correlate with various human cancers. We investigated the clinical significance of miR-10b and its involvement in chemotherapeutic resistance to 5-fluorouracil (5-FU), which is a key component of common chemotherapy regimens in colorectal cancer.Methods
Quantitative RT-PCR was used to evaluate the clinicopathologic significance of miR-10b expression in 88 colorectal cancer cases. We also investigated the chemotherapeutic sensitivity to 5-FU in miR-10b-overexpressing colorectal cancer cells. To explore the mechanism of chemoresistance in miR-10b transfected cells, we examined whether miR-10b inhibits the pro-apoptotic BH3-only Bcl-2 family member BIM(BCL2L11), a key mediator of chemotherapy-induced cell death.Results
High level miR-10b expression was found to be significantly associated with high incidence of lymphatic invasion (P?=?0.0257) and poor prognosis (P?=?0.0057). Multivariate analysis indicated that high miR-10b expression is an independent prognostic factor for survival. In vitro studies revealed that miR-10b directly inhibits pro-apoptotic BIM, and the overexpression of miR-10b confers chemoresistance in colorectal cancer cells to 5-FU.Conclusions
MiR-10b is a novel prognostic marker in colorectal cancer. Moreover, the expression of miR-10b is a potential indicator of chemosensitivity to the common 5-FU-based chemotherapy regimen. 相似文献103.
Yuichiro Kato Masaru Konishi Takahiro Kinoshita Shinichiro Takahashi Naoto Gotohda Taira Kinoshita 《Surgery today》2012,42(12):1240-1243
We report a rare case of an intraductal oncocytic papillary neoplasm (IOPN) of the extrahepatic bile duct. A 66-year-old man was admitted to our hospital for investigation of right-sided back pain. Ultrasonography, computed tomography and magnetic resonance imaging showed a papillary lesion, 3?cm in diameter, in the middle bile duct, invaginating into the cystic duct. We made a provisional diagnosis of middle bile duct cancer and performed substomach-preserving pancreatoduodenectomy. Macroscopically, the middle bile duct contained a two-humped papillary tumor, one tip of which invaginated into the cystic duct. Microscopically, the tumor consisted of cuboidal cells with abundant eosinophilic cytoplasm resembling that of oncocytes and a fine fibrovascular core. The tumor cells were stained strongly with antimitochondria antibody. Based on these findings, the tumor was diagnosed histologically as IOPN of the extrahepatic bile duct. The patient died of prostate cancer 51?months after surgery, but without evidence of recurrence of the IOPN. 相似文献
104.
Postoperative cytology for drained fluid from the pancreatic bed after "curative" resection of pancreatic cancers: does it predict both the patient's prognosis and the site of cancer recurrence? 总被引:1,自引:0,他引:1 下载免费PDF全文
Ishikawa O Wada H Ohigashi H Doki Y Yokoyama S Noura S Yamada T Sasaki Y Imaoka S Kasugai T Matsunaga T Takenaka A Nakaizumi A 《Annals of surgery》2003,238(1):103-110
OBJECTIVE: To evaluate the postoperative cytology of drained fluid from the pancreatic bed as a predictive indicator of local recurrence after curative (R0) resection of pancreatic cancer. SUMMARY BACKGROUND DATA: The pancreatic bed offers a common site of cancer recurrence (local recurrence), even after curative (R0) resection is performed for pancreatic cancer. If local recurrence is thereby predicted precisely, soon after surgery, we have a chance to treat it by adding radiation or some other locoregional therapy before it can grow or spread beyond the pancreatic bed. However, there have been no previous reports of cytology performed on the drained fluid after pancreatectomy. METHODS: This study includes 94 patients who had shown negative results in the peritoneal washing cytology before resection and subsequently received pancreatectomies for pancreatic tumors. They consisted of 12 benign tumors, 17 noninvasive or minimally invasive carcinomas and 65 invasive ductal carcinomas (R0 = 58; R1/2 = 7). Postoperatively, the drained fluid from the pancreatic bed was collected for 24 hours and used for cytologic examination. The cytologic results were examined in association with the histopathology of the resected tumor, patient's survival, and mode of cancer recurrence, including local recurrence. RESULTS: Patients with benign tumors or noninvasive/minimally invasive carcinomas had negative result in cytology, and none of them have died of local recurrence (limited to the pancreatic bed) to date. However, patients with invasive ductal carcinoma revealed higher cytology-positive rates: 28% (16/58) in curative (R0) resection; and 71% (5/7) in noncurative (R1/2) resection. Among 58 patients with R0 resection, the 3-year survival rate was 14% in 16 cytology-positive patients and 55% in 42 cytology-negative patients (P < 0.05). The 3-year cumulative rate of local recurrence was 85% and 23%, respectively (P < 0.05). Compared with other histopathologic parameters obtained from the resected specimens, the drain cytology was more specific in predicting the subsequent development of local recurrence. CONCLUSIONS: Drain-cytology was a quick examination that enabled us to specifically indicate both minute residual cancer and subsequent development of local recurrence even after R0 resection of pancreatic cancer. 相似文献
105.
Surgical influence on TH1/TH2 balance and monocyte surface antigen expression and its relation to infectious complications 总被引:6,自引:0,他引:6
Tatsumi H Ura H Ikeda S Yamaguchi K Katsuramaki T Asai Y Hirata K 《World journal of surgery》2003,27(5):522-528
Abstract
Malignancy and operation for it cause several alterations in immune function that are considered to be concerned with the
development of infectious complications. Forty-three patients who underwent curative surgery for gastrointestinal malignancies
were entered into this study and were divided into two groups, those with and those without postoperative infection. Changes
in the proportion of Th1/Th2 subsets in CD4+ T cells and the expression of human leukocyte antigen (HLA)-DR and CD16a molecules on monocytes were measured by flow cytometry
before and after surgery. We performed intracellular cytokine stainings to exactly detect Th1/Th2 subsets. The proportions
of interferon-γ-producing CD4+ T (Th1) cells in the preoperative state were almost equal in the two groups, and the proportion decreased on postoperative
day (POD) 1 in both groups. On POD 7, the proportion of Th1 cells recovered to the preoperative level in the noninfection
group, while the suppression was further reinforced in the infection group (26.8% versus 18.3%, p < 0.005). In contrast, the proportion of interleukin-4-producing CD4+ T (Th2) cells in the infection group (11.3%) was already suppressed in the preoperative state when compared with the noninfection
group (17.3%, p < 0.005). Changes in HLA-DR and CD16a expression on monocytes were similar to the changes in the proportion of Th1 cells.
These results indicate that the suppression of Th1 cell and monocyte functions during the early phase of the postoperative
course was directly related to the occurrence of infectious complications and that several immunological impairments have
already occurred in the preoperative state in cancer patients.
Electronic Publication 相似文献
106.
Cytokeratin deposits in lymph nodes show distinct clinical significance from lymph node micrometastasis in human esophageal cancers 总被引:6,自引:0,他引:6
Doki Y Ishikawa O Mano M Hiratsuka M Sasaki Y Kameyama M Ohigashi H Murata K Yamada T Miyashiro I Yokoyama S Ishiguro S Imaoka S 《The Journal of surgical research》2002,107(1):75-81
BACKGROUND: Cytokeratin immunostaining is the most common method used to identify micrometastatic cancer cells from the lymph nodes. However, contamination with hyalinized cytokeratin particles, frequently observed in the lymph nodes of esophageal cancer patients, can lead to misinterpretation of cytokeratin immunostaining. MATERIALS AND METHODS: Cytokeratin immunostaining (AE1/AE3) of surgically removed lymph nodes was performed for 41 cases of node-negative, but locally advanced (T3, T4), esophageal cancer patients. Cytokeratin immunoreactivity (CK) was classified as micrometastasis (MM) or cytokeratin deposit (CD) by the presence or absence of tumor nuclei in serial sections given hematoxylin-eosin staining. RESULTS: CK (+) was observed in 18 patients (44%), including 11 with MM (+) (27%) and 10 with CD (+) (24%). There was no correlation between MM and CD, and neither was associated with clinicopathological factors, except for a high incidence of preoperative chemotherapy in CD (+) patients. The presence of CK did not affect postoperative survival of esophageal cancer patients at this limited stage, showing a 5-year survival rate of 57% for CK (+) and 64% for CK (-) (P = 0.6064). Interestingly, patients with MM (+) showed poorer prognosis than MM (-) (5-year survival: 28% vs 79%, P = 0.0188), while CD (+) patients tended to display better prognosis than CD (-) ones (5-year survival: 78% vs 56%, P = 0.1860). CONCLUSIONS: Evaluation by cytokeratin immunostaining of lymph nodes requires careful discrimination of CD from MM, in order to allow MM to be used as a prognostic factor for esophageal cancer patients. 相似文献
107.
Mizuguchi T Katsuramaki T Morishita K Kawamoto M Nobuoka T Imamura M Kimura Y Hirata K 《Digestive surgery》2006,23(1-2):115-118
Hepatectomy for secondary liver cancer that has invaded the inferior vena cava (IVC) can be the only way to achieve long-term survival. We describe a method for hepatectomy combined with partial IVC resection without venous bypass circulation and an in situ graft-trimming method to avoid graft size mismatch after reconstruction. We carried out left hepatectomy extended to segment 1 with partial IVC resection first. During resection and reconstruction of the IVC, it was clamped below the right hepatic vein and above the inferior right hepatic vein to maintain systemic circulation. The graft was trimmed in situ, after a half running suture of the graft was finished to ensure the correct size. Preservation of both inferior right hepatic vein and right hepatic vein helps to maintain systemic circulation during reconstruction of the IVC. The in situ graft-trimming method is an easy and safe method to ensure the correct graft size after IVC reconstruction. 相似文献
108.
Yoshiaki?Shinden Akihiro?NakajoEmail author Hideo?Arima Kiyonori?Tanoue Munetsugu?Hirata Yuko?Kijima Kosei?Maemura Shoji?Natsugoe 《World journal of surgery》2017,41(6):1506-1512
Background
Intraoperative identification of the difficult-to-spot parathyroid gland is critical during surgery for thyroid and parathyroid disease. Recently, intrinsic fluorescence of the parathyroid gland was identified, and a new method was developed for intraoperative detection of the parathyroid with an original fluorescent detection apparatus. Here, we describe a method for intraoperative detection of the parathyroid using a ready-made photodynamic eye (PDE) system without any fluorescent dye or contrast agents.Methods
Seventeen patients who underwent surgical treatment for thyroid or parathyroid disease at Kagoshima University Hospital were enrolled in this study. Intrinsic fluorescence of various tissues was detected with the PDE system. Intraoperative in vivo and ex vivo intrinsic fluorescence of the parathyroid, thyroid, lymph nodes and fat tissues was measured and analyzed.Results
The parathyroid gland had a significantly higher fluorescence intensity than the other tissues, including the thyroid glands, lymph nodes and fat tissues, and we could identify them during surgery using the fluorescence-guided method. Our method could be applicable for two intraoperative clinical procedures: ex vivo tissue identification of parathyroid tissue and in vivo identification of the location of the parathyroid gland, including ectopic glands.Conclusion
The PDE system may be an easy and highly feasible method to identify the parathyroid gland during surgery.109.
Yasunari?Fukuda Daisaku?Yamada Hidetoshi?EguchiEmail author Yoshifumi?Iwagami Takehiro?Noda Tadafumi?Asaoka Hiroshi?Wada Koichi?Kawamoto Kunihito?Gotoh Masaki?Mori Yuichiro?Doki 《Surgery today》2017,47(10):1180-1187
Purpose
A thick pancreas has proven to be a conspicuous predictor of pancreatic fistula (PF) following distal pancreatectomy (DP) using staples. Other predictors for this serious surgical complication currently remain obscure. This study sought to identify novel predictors of PF following DP.Methods
One hundred and twenty-two patients were retrospectively assessed to determine the correlation between PF occurrence and the clinicopathological findings and radiologic data from preoperative computed tomography (CT). CT assessments included the thickness of the pancreas (TP) and pancreatic CT number (pancreatic index; PI), calculated by dividing the pancreatic CT by the splenic CT density.Results
Twenty-four patients (19.7%) developed a clinically relevant PF. TP was identified as an independent risk factor for PF in multivariate analyses (odds ratio 1.17; P?=?0.0095). In subgroup analyses, a lower PI in a thick pancreas was a significant predictor of PF (P?=?0.032). The combination of these two prediction parameters, known as the TP-to-PI ratio (TPIR), showed a significantly better prediction ability than TP alone (area under the receiver operating characteristic curve for the incidence of PF, TPIR 0.80 vs. TP 0.69; P?=?0.037).Conclusion
Combining the CT number with TP substantially improves the prediction ability for the incidence of PF following DP with staple use.110.
Taishi?HataEmail author Hidekazu?Takahashi Daisuke?Sakai Naotsugu?Haraguchi Junichi?Nishimura Toshihiro?Kudo Matsuda?Chu Ichiro?Takemasa Satoh?Taroh Tsunekazu?Mizushima Yuichiro?Doki Masaki?Mori 《Surgery today》2017,47(11):1372-1377