全文获取类型
收费全文 | 16032篇 |
免费 | 692篇 |
国内免费 | 1120篇 |
学科分类
医药卫生 | 17844篇 |
出版年
2024年 | 30篇 |
2023年 | 85篇 |
2022年 | 60篇 |
2021年 | 68篇 |
2020年 | 49篇 |
2019年 | 46篇 |
2018年 | 42篇 |
2017年 | 29篇 |
2016年 | 37篇 |
2015年 | 60篇 |
2014年 | 129篇 |
2013年 | 61篇 |
2012年 | 2557篇 |
2011年 | 2763篇 |
2010年 | 456篇 |
2009年 | 244篇 |
2008年 | 1773篇 |
2007年 | 1675篇 |
2006年 | 1515篇 |
2005年 | 1377篇 |
2004年 | 1153篇 |
2003年 | 984篇 |
2002年 | 838篇 |
2001年 | 511篇 |
2000年 | 612篇 |
1999年 | 308篇 |
1998年 | 111篇 |
1997年 | 46篇 |
1996年 | 20篇 |
1995年 | 19篇 |
1994年 | 10篇 |
1993年 | 6篇 |
1992年 | 6篇 |
1990年 | 5篇 |
1989年 | 19篇 |
1988年 | 10篇 |
1987年 | 18篇 |
1986年 | 6篇 |
1985年 | 11篇 |
1984年 | 16篇 |
1983年 | 11篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1966年 | 3篇 |
1965年 | 3篇 |
1963年 | 6篇 |
1960年 | 3篇 |
1958年 | 5篇 |
1957年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
1.
2.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them.
OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia.
DESIGN: A randomized controlled trial.
SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University.
MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden).
METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling.
MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group.
RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05)
CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis. 相似文献
3.
With the method of rapid gel sequencing, the complete nueleotide sequence of Fasciolopsis buski 5S rRNA has been determined: AAC GGG AUG AAG CUA GAC AUG UGG CGG CCU AGU UGG AGG UCG GAA CUC GGA AGU UAA GGA AUG UUG GGC CUG GUU AGU ACU GGU AUG GGU GAC CUU GGG AAU ACC GGG UGU UGC GUC CA_(OH) This have been compared with 553 species of other organisms 5S rRNA sequences previously published and fitted to a secondary structural model. 相似文献
4.
Zhong Rui-kun钟瑞琨 Dong Yong-he董永和and Lu Dao-pei陆道培Institute of Hematology Beijing Medical University Beijing 《中华医学杂志(英文版)》1989,102(7):537-544
In order to understand the mechanism of immunosuppression caused by infusion of placental gamma globulin (PGG) in patients with renal allografts, rheumatoid arthritis, and graft – versus –host disease (GCHD) following bone marrow transplantation (BMT) ,we have examined the effect of PGG in vitro and in a model of the xenogeneic , local graft –ver- sus – host reaction (LGVHR) .PGG inhibited lymphocyte proliferation in mixed lymphocyte cultures (MLC) (P<0.005) and depressed interleukin -2 (IL-2) levels in such cultures at 72 hours (P<0.01) . In contrast phytohemagglutinin (PHA) –and pokeweed mitogen (PWM) –induced T and B lymphocyte blastogenesis was not affected by such PGG treatment .PGG treatment .PGG neither decreased the [3H] TdR pulse incorporation in unstimulated lymphocytes nor affected cell viability .Cell cycle analysis by flow cytometry showed that PGG reduced the percentage of cells in S and G2, M phases during the MLC, but did not alter cell cycling during PWM-stimulated proliferation .
An immunosuppressive effect of PGG on the LGCHR was tested in a model of intracutaneous transplantation of PGG –treat human lymphocytes into cyclophosphamide – immunosuppressed rats. Lymphoprep – separated human tonsillar lymphocytes were incubated with RPMI-1640 buffer containing:(1)PGG,4mg/ml,(2) human plasma albumin,4mg/ml,(3)mitomycin-C,25ug/ml, or (4) no additive. Cell of each preparation (3x107cells in 0.1ml) were injected intracutaneously into cyclophosphamide-treated male rats at separate abdominal locations. A fifth site received only the buffer solution. Five days after injection of cells ,each rat received [125 I]IUdR (10uCi) intraperitoneally and was killed after 5 hours. For each site of injection, the diameters of induration were measured and 125 I was counted . There was no difference between buffer – treated and a ibumin – treated groups either in the diameter of the area of induration (t=0.66;P>0.5)or in radioactive counts(t=0.22;P>0.05).In the PGG –treated group, the induration and radioactivity measurements were significantly less than in control groups (t=3.72 and P<0.1;t=2.62 and P<0.02,respectively ) Cytophilic antibodies in PGG were thought to inhibit an early phase of T cell activation, and not to be cytotoxicity .In the LGVHR, the immune response might be abrogated either by immuno- regulatory suppression of T cell function or by toxicity to the infused lymphoid cells. For some clinical purposes, immuno- modulating, human antibodies might be preferred to murine, monoclonal antibodies. 相似文献
5.
Effect of Ligustrazine on Bone Marrow Microenvironment and Signal Transducti on Path in Irradiation Injured Mice 下载免费PDF全文
Lan Sun Wen-li Liu Han-ying Sun Tian-hua Ren Deng-ju Li Hui-zhen Xu Wu Lu 《中国结合医学杂志》2002,8(4):295-298
Wehavereported previouslythatligustrazinecouldpromotehematopoiesisthroughimprovingbonemarrowmicroenvironmentandenhancingadhesive 相似文献
6.
Lu Chen-zhao陆辰照 Guo Bang-fu过邦辅Shanghai Institute of Traumatology; Department of Traumatology Orthope-dics Ruijin Hospital Shanghai Second Medical University Shanghai 《中华医学杂志(英文版)》1987,100(1):68-74
In the management of ankle joint fractures, re-
duction and fixation of the lateral malleolus should
be emphasized. The lateral maUeolus should have
anatomical reduction and fixation should be reliable.
Fibular integrity is essential in stabilizing the
ankle joint. Routine section of the fibula may result
in separation of the inferior tibiofibular joint, ankle
instability and talus displacement. Eventually this
leads to traumatic arthritis. So special attention
should be paid to fibular resection, even partial
removal of the fibula for transplantation should be
carried out carefully. 相似文献
7.
Tian YF Lin YS Lu CL Chia CC Huang KF Shih TY Shen KH Chung MT Tsai YC Chao CH Wu MP 《Journal of minimally invasive gynecology》2007,14(3):284-292
STUDY OBJECTIVES: This follow-up study examined the major complications among 4307 operative gynecologic laparoscopies. The overall complication rate and each individual category were compared with those of our previous study period. The clinical outcome and salvage procedures were correlated with the time of recognition and the severity of initial procedures in the individual injury type. DESIGN: Retrospective, comparative study based on medical record reviewing (Canadian Task Force classification II-3). SETTING: Tertiary teaching hospital, Chi Mei Foundation Hospital in southern Taiwan. PATIENTS: Records of women (n = 4307) aged 40.5 +/- 11.7 years (mean +/- SD [95% CI 40.1-40.5]) who underwent operative gynecologic laparoscopies from January 2000 through February 2006 were reviewed in this study. The complications were compared with those of our previous study based on 1507 laparoscopies performed between December 1992 and November 1999 for follow-up comparison. INTERVENTIONS: Gynecologic laparoscopic surgeries. MEASUREMENTS AND MAIN RESULTS: Thirty-four complications occurred in 31 patients requiring repair procedures, 3 of whom had multiple complications, with an overall complication rate of 0.72% (31/4307). There were 13 bladder injuries (0.30%), 7 bowel injuries (0.16%), 3 cases of internal bleeding (0.07%), 4 vaginal stump hematomas or abscesses (0.09%), 3 ureteral injuries (0.07%), 3 major vessel injuries (0.07%), and 1 trocar site hematoma (0.02%). In addition, there were 125 (2.88%) postoperative blood transfusions without additional operative intervention. The major complication rate decreased compared with that of the previous study (0.72% [95% CI 0.51%-1.02%] vs 1.59% [95% CI 1.07%-2.36%]; p = .005). The overall complication rates were not significantly different between laparoscopic hysterectomy (LH) group and non-LH group. However, bladder injury happened more frequently in the LH group, whereas bowel injury was more common in the non-LH group. In addition, the severity of the original injury, timing of recognition, and accompanying salvage procedures correlated with the clinical outcomes. CONCLUSION: The significantly decreased major complication rate, as compared with that of our previous study period, confirms the importance of experience accumulation and use of preventive maneuvers in reducing the complication rate. There were no significant differences among the individual injury category during these 2 study periods. The manifestations of bowel injury were highly variable and individualized. The accumulation of surgical experience with the aid of preventive maneuvers is helpful to reduce the complication rate significantly. 相似文献
8.
彩色超声多普勒在肝硬变和门脉高压症疹治中的应用 总被引:1,自引:0,他引:1
近二十年来,腹部超声在胃肠道疾病和肝脏疾病的诊断方面显示出重要作用。随着超声多普勒在神经病学、血管病学、心脏病学以及妇产科学中的成功应用.正越来越多地被用于腹部血管疾病的诊治。 相似文献
9.
术中射频消融后病灶刮除治疗脊柱转移瘤 总被引:2,自引:1,他引:1
李浩淼 Alessandro Gasbarrini Michele Cappuccio Rakesh Donthineni Lu Boriani Stefano Bandier Laur Foroni Gianandre Pasquinelli Stefano Boriani 《中国脊柱脊髓杂志》2008,18(11)
目的:探讨术中射频消融(RFA)后再行病灶刮除术治疗脊柱转移瘤的可行性及疗效.方法:2004年~2006年,对11例脊柱转移瘤患者术中实施RFA后再行病灶刮除术,将FRA前后病灶标本进行光镜和电镜病理检查,随访患者疼痛缓解情况及肿瘤复发情况.结果:术中未出现脊髓和神经根损伤,RFA后瘤组织固缩,刮除顺利,出血量350~3800ml,平均1024.5ml.全部病例得到6个月以上随访,平均9.8个月,全部患者生存期超过6个月,VAS评分术前平均5.8分,术后6个月时平均1.9分.1例出现局部肿瘤复发.RFA前的标本光、电镜检查均未见肿瘤组织坏死.RFA后光镜检查3例无明显坏死,9例肿瘤细胞完全坏死:电镜检查10例肿瘤细胞完全坏死,1例肿瘤细胞部分坏死,1例无明显坏死.结论:术中RFA后再行病灶刮除治疗脊柱转移瘤安全可行,有利于肿瘤的刮除,减少局部复发的风险. 相似文献
10.
Zhao P Qin ZL Ke JS Lu Y Liu M Pan W Zhao LJ Cao J Qi ZT 《第二军医大学学报》2005,26(10):1167-1167
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed. 相似文献