首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   396篇
  免费   31篇
  国内免费   3篇
儿科学   10篇
妇产科学   25篇
基础医学   64篇
口腔科学   5篇
临床医学   24篇
内科学   76篇
皮肤病学   28篇
神经病学   31篇
特种医学   9篇
外科学   56篇
综合类   17篇
一般理论   1篇
预防医学   23篇
眼科学   2篇
药学   33篇
肿瘤学   26篇
  2023年   3篇
  2022年   5篇
  2021年   12篇
  2020年   12篇
  2019年   5篇
  2018年   6篇
  2016年   4篇
  2015年   9篇
  2014年   10篇
  2013年   11篇
  2012年   11篇
  2011年   23篇
  2010年   14篇
  2009年   6篇
  2008年   19篇
  2007年   10篇
  2006年   23篇
  2005年   20篇
  2004年   13篇
  2003年   16篇
  2002年   12篇
  2001年   9篇
  2000年   15篇
  1999年   8篇
  1998年   4篇
  1997年   5篇
  1996年   2篇
  1995年   4篇
  1994年   4篇
  1993年   4篇
  1992年   10篇
  1991年   9篇
  1990年   10篇
  1989年   10篇
  1988年   8篇
  1987年   9篇
  1986年   13篇
  1985年   6篇
  1984年   10篇
  1983年   5篇
  1982年   2篇
  1981年   2篇
  1980年   4篇
  1979年   4篇
  1978年   4篇
  1976年   4篇
  1975年   4篇
  1974年   4篇
  1973年   3篇
  1969年   2篇
排序方式: 共有430条查询结果,搜索用时 15 毫秒
1.
2.
Experience in treating Pott's Paraplegia in a rural general hospital in Northern Kenya is reported. Five TB patients with severe neurological involvement of the spine were treated by orthopaedic reduction and antituberculous drugs. All were able to walk three months later.  相似文献   
3.
We studied the changes in the anti-oxidant capacity of tissues, such as heart, liver, and blood in male and female rats, as a parameter for evaluating oxidative stress after either a prolonged (210 min) or an exhausting bout of swimming. Furthermore, we also investigated exercise-induced changes in the electrophysiological properties, measured in vitro, of papillary muscle fibres. Small decreases of anti-oxidant capacities after prolonged exercise [0.10 (SEM 0.04) in heart, 0.43 (SEM 0.19) in liver, 0.22 (SEM 0.05) in blood] and greater decreases after exhausting exercise [0.23 (SEM 0.04) in heart, 0.90 (SEM 0.29) in liver, 0.34 (SEM 0.04) in blood] were found in tissues from the male rats. For the female rats, similar changes were found only in the blood [0.11 (SEM 0.07) and 0.35 (SEM 0.06) for prolonged and exhausting exercise, respectively]. Liver and heart anti-oxidant capacity remained unchanged after prolonged exercise, while after exhausting swimming it underwent a decrease almost the same as found in the male rats, though the swimming time to exhaustion (endurance capacity) was much greater [706 (SEM 10) min and 444 (SEM 32) min for the females and males, respectively]. The duration of the action potential, recorded from papillary muscle fibres, underwent changes related to the decreases in heart anti-oxidant capacity. In fact, the action potential duration (APD) was shorter only in preparations from the male rats after prolonged exercise, but in all preparations after exhausting exercise. After such exercise, the APD was similar for the male and female rats [37.1 (SEM 3.4) ms and 37.0 (SEM 3.6) ms, respectively]. Such a pattern was independent of stimulation frequency, since it was found substantially unchanged when the frequency was increased from 1 to 5 Hz. We concluded that the different susceptibilities to the effects of physical exercise, exhibited by tissues from these male and female rats might have been related to different capacities to oppose oxidative stress effectively.  相似文献   
4.
To determine whether preliminary assessment of ovarian reserve by simultaneous evaluation of basal follicle-stimulating hormone (FSH) and oestradiol response to gonadotrophin releasing hormone (GnRH) analogue (F-G-test) can be used to tailor individually the drug regimen for ovarian stimulation, the in-vitro fertilization (IVF) results of 238 patients were retrospectively analysed. Sixty-two women with abnormal response to the test (DeltaE2 <180 pmol/l and/or FSH >9.5 mIU/ml) had commenced buserelin nasal spray in the mid-luteal phase and discontinued it on cycle day 1. Ovarian stimulation was started on cycle day 3 with 375 IU/day of gonadotrophin. Fifty-three patients completed the treatment cycle (group A). A total of 176 women with normal response to the test (DeltaE2 >180 pmol/l and FSH <9.5 mIU/ml) had continued the GnRH analogue throughout the stimulation cycle and a starting dose of 225 IU/day of gonadotrophin was used from cycle day 3. A total of 158 patients completed the treatment cycle (group B). Group A had significantly higher age (34.9 +/- 4.2 versus 33.2 +/- 4.2) (P < 0.05) and basal FSH (9.2 +/- 3.8 versus 7.0 +/- 2.2) (P < 0.05) and required a higher total dose of gonadotrophin. The numbers of oocytes retrieved and embryos transferred were significantly lower. However, fertilization, clinical pregnancies, and implantation rates were similar in both groups. It was concluded that simultaneous evaluation of basal FSH and oestradiol response to GnRH analogue can be useful in identifying subcategories of women with reduced ovarian reserve who may benefit from reduced GnRH analogue administration and a higher starting dose of gonadotrophin.  相似文献   
5.
IntroductionAs we progress to an era when patient autonomy and shared decision-making are highly valued, there is a need to also have effective patient-centered communication tools. Radiology reports are designed for clinicians and can be very technical and difficult for patients to understand. It is important for patients to understand their magnetic resonance imaging (MRI) report in order to make an informed treatment decision with their physician. Therefore, we aimed to create a patient-centered prostate MRI report to give our patients a better understanding of their clinical condition.MethodsA prototype patient-centered radiology report (PACERR) was created by identifying items to include based on opinions sought from a group of patients undergoing prostate MRI and medical experts. Data was collected in semi-structured interviews using a salient belief question. A prototype PACERR was created in collaboration with human factors engineering and design, medical imaging, biomedical informatics, and cancer patient education groups.ResultsFifteen patients and eight experts from urology, radiation oncology, radiology, and nursing participated in this study. Patients were particularly interested to have a report with laymen terms, concise language, contextualization of values, definitions of medical terms, and next course of action. Everyone believed the report should include the risk of MRI findings actually being cancer in the subsequent biopsy.ConclusionsA prostate MRI PACERR has been developed to communicate the most important findings relevant to decision-making in prostate cancer using patient-oriented design principles. The ability of this tool to improve patient knowledge and communication will be explored.  相似文献   
6.
Three patients affected by the congenital mono-ophthalmia syndrome were submitted to horizontal eye movements recording. The aim was to study the nystagmus and its characteristics, in order to give information that could explain signs and symptoms of the syndrome. Eye movements recording and analysis displayed a jerk nystagmus with a decreasing-velocity exponential slow phase, characteristic of a latent/manifest-latent nystagmus. The intensity of nystagmus decreased in adduction of the viewing eye, and increased in abduction in accordance with Alexander's law. The fast phase was toward the viewing eye. There was no reversal of the fast phase, nor an instability of gaze in the blind eye.  相似文献   
7.
Red blood cell energy metabolism during cardiopulmonary bypass   总被引:1,自引:0,他引:1  
BACKGROUND: During cardiopulmonary bypass (CPB) an intracellular ATP deficit could theoretically play a role in changes of erythrocyte shape and deformability caused by mechanical trauma. We therefore studied erythrocyte energy metabolism in 12 patients undergoing normothermic CPB for myocardial revascularization. METHODS: Blood samples were collected prior to and 45 minutes after CPB beginning and analyzed for erythrocyte ATP, ADP, and AMP and their metabolites, erythrocyte NAD and NADP, plasma and whole blood lactate (Lact(p) and Lact(b) respectively), and whole blood pyruvate (Pyr(b)). RESULTS: Values were expressed as mean +/- standard deviation or median (lower and higher quartiles) on the ground of a test for normality. During CPB erythrocyte nucleotides and their metabolites did not change significantly (ATP: 60.2+/-12.1 vs. 68.3+/-13.0; ADP: 12.2+/-3.6 vs. 12.0+/-3.1; AMP: 0.43+/-24 vs. 0.44+/-0.26; adenosine: 0.063 (0.034-0.203) vs. 0.77 (0.032-0.221); inosine: 0.064 (0.023-0.072) vs. 0.075 (0.025-0.111); hypoxanthine: 0.330+/-0.272 vs. 0.367+/-0.223; xanthine: 0.193+/-0.090 vs. 0.220+/-0.095; NAD: 3.149+/-0.743 vs. 3.358+/-0.851; values in microM/mM packed red blood cell hemoglobin) while NADP increased (2.110+/-0.390 vs. 2.433+/-0.288 microM/mM packed red blood cell hemoglobin; p<0.05). Ringer lactate, with which the extracorporeal circuit was primed, caused Lact(p) to increase (1.87+/-0.81 vs. 3.27+/-1.15 mM/l; p<0.01). Some lactate entered erythrocytes since Lact(p)/Lact(b) ratio did not change (1.09+/-0.25 vs. 1.07+/-0.23) and some was transformed into pyruvate since Pyr(b) increased [62.9 (30.3-73.3) vs. 100.5 (61.0-146.9) microM/l; p<0.01]. Lact(b)/Pyr(b) ratio did not change significantly [22.6 (16.1-40.5) vs. 27.9 (17.5-35.2)] so that NAD/NADH ratio and, consequently, the rate of glycolysis were unlikely to change too. CONCLUSIONS: Erythrocyte energy metabolism is not affected by CPB, at least during the period of time taken into account in this study.  相似文献   
8.
BACKGROUND: Systems for Target Controlled Infusion accepting not only patient' data, like Diprifusor, but also a pharmacokinetic model have not been available in Italy in the last years. Therefore a program which controls a Pilot Anesthesia Vial pump and accepts any pharmacokinetic model was developed and applied to propofol infusion for anaesthesia and sedation. METHODS: Two versions of the Visual TCI program have been developed. The first, at intervals, supplies the anaesthetist with the values for the pump; the second directly interacts with the pump. The program also supplies the anaesthetist with the current amount of drug in each compartment and with the estimated awakening time. DESIGN: preliminary prospective study. SETTING: operatory theatre and Intensive Care Unit in a University Hospital. Patients: 6 patients undergoing total intravenous anaesthesia with propofol and fentanyl for abdominal surgery; 6 patients undergoing sedation with propofol in an Intensive Care Unit (the first 4-hour period was taken into account). Interventions: propofol infusion was regulated by the Visual TCI program. The first version was employed in three patients of each group and the second one in the others. Hypo- and hypertensive episodes (systolic pressure less than 80 mmHg or higher than basal value plus 25%) were recorded during anaesthesia and sedation. Propofol concentration was measured in plasma three times at defined intervals and per cent differences between measured and computer-calculated values (Predictive error, PE) were calculated. RESULTS: No hypo- or hypertensive episodes were recorded. PE was 27.4 +/- 17.9%. CONCLUSIONS: The program was easily employed, caused no inconvenience, and its use was associated with a remarkable cardiovascular stability. PE distribution was acceptable on the ground of the criteria reported in the literature. The program can be applied to drugs other than propofol, with both two and three compartment pharmacokinetic models and the anaesthetist can choose the most suitable model for the patient.  相似文献   
9.
Modification of the alpha-carbamate substituent of isoxazoline GPIIb/IIIa (alphaIIb beta3) antagonist DMP 754 (7) led to a series of alpha-sulfonamide and alpha-sulfamide diaminopropionate isoxazolinylacetamides which were found to be potent inhibitors of in vitro platelet aggregation. Aryl- and heteroaryl-alpha-sulfonamide groups, in conjunction with (5R)-isoxazoline (2S)-diaminopropionate stereochemistry, were found to impart a pronounced duration of antiplatelet effect in dogs, potentially due to high affinity for unactivated platelets. Isoxazolylsulfonamide 34b (DMP 802), a highly selective GPIIb/IIIa antagonist, demonstrated a prolonged duration of action after iv and po dosing and high affinity for resting and activated platelets. The prolonged antiplatelet profile of DMP 802 in dogs and the high affinity of DMP 802 for human platelets may be predictive of clinical utility as a once-daily antiplatelet agent.  相似文献   
10.
Epidermal growth factor receptor (EGFr) and p185neu protein were measured in 55 samples of carcinoma and 55 of normal colorectal mucosa from the same patient, using a ligand binding assay and an ELISA method respectively. The binding characteristics of EGFr were similar in cancer and normal tissue. The concentrations of both EGFr and p185 showed gaussian distribution and were not significantly different between normal and cancer tissue, although a trend toward higher levels of EGFr in normal mucosa was found. Moreover, no significative variations were found in the ratios between cancer and normal tissue after desaturation of the EGFr. No correlations were found between EGFr and p185 and the main clinopathological parameters.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号