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111.
应用声振仪对1992年2个月~1993年6个月单胎36~43周妊娠孕妇150例进行了声音振动刺激试验(VAS-T)并与无负荷试验(NST)对照。对此结果VAS-T(+)146例,(-)4例,NST反应型96例,无反应型54例。NST无反应型预测价值8%,假阴性率92%。NST无反应型经声音刺激后50例成VAS-T(+)。VAS-T预测价值99.3%。NST有效率66%,VAS-T有效率99%。NST至少需做20min,VAS-T95%在3min内达到标准,最长15min。为避免NST假无反应型,应进行VAS-T。  相似文献   
112.
We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count, can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions. The automated features have enhanced the utility of the NMMS. The prime advantages of this system are (1) the ability to customize its features by altering its controlling programs, (2) the ready availability of the hardware and software, (3) the general purpose nature of the system, so that it is not limited to this one application, and (4) the adaptable nature of the system.  相似文献   
113.
Summary Twenty-two persons (20 men and 2 women) were examined for their external and internal exposure to the glycol ether 1-methoxypropan-2-ol (PGME) during the production, leak testing and mounting of brake-hoses. For the measurement of external exposure, personal air monitoring was the method of choice. Average concentrations of PGME of 82.2 mg/m3 (22.3 ppm), 68.6 mg/m3 (18.6 ppm) and 11.3 mg/m3 (3.1 ppm) were found in the air of the brakehose production, leak test and mounting areas, respectively. For the estimation of internal exposure to PGME, this glycol ether was measured in both urine and blood. The biological samples were taken post-shift. The highest internal exposure levels were found in the brakehose production section and in the leak test area. The average post-shift concentrations for PGME in workers in the brakehose production section were 4.6 mg/l in urine and 13.5 mg/l in blood; the corresponding figures for workers in the leak test area were 4.2 mg/l in urine and 11.0 mg/l in blood. In blood and urine samples of workers engaged in the mounting area, PGME levels were below the detection limits. The elimination kinetics of PGME were also studied in three highly exposed persons, and mean excretion half-lives of PGME of approximately 4.4 h were found. On the basis of our results we made a rough calculation of a future biological tolerance value: we would except that concentrations of 38-109 mg per litre of blood and 10–31 mg per litre of urine would correspond to the German MAK value for PGME (375 mg/m3).  相似文献   
114.
115.
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc.  相似文献   
116.
End-tidal Carbon Dioxide Monitoring during Procedural Sedation   总被引:2,自引:0,他引:2  
OBJECTIVE: To prospectively determine whether end-tidal carbon dioxide (ETCO2) monitors can detect respiratory depression (RD) and the level of sedation in emergency department (ED) patients undergoing procedural sedation (PS). METHODS: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS. Patients were monitored for vital signs, depth of sedation per the physician by the Observer's Assessment of Alertness/Sedation scale (OAA/S), pulse oximetry, and nasal-sample ETCO2 during PS. Respiratory depression was defined as an oxygen saturation <90%, an ETCO2 >50 mm Hg, or an absent ETCO2 waveform at any time during the procedure. The physician also determined whether protective airway reflexes were lost during the procedure and assisted ventilation was required, or whether there were any other complications. Rates of RD were compared with the physician assessment of airway loss and between agents using chi-square statistics. Spearman's rho analysis was used to determine whether there was a correlation between ETCO2 and the OAA/S score. RESULTS: Seventy-four patients were enrolled in the study. Forty (54.1%) received methohexital, 21 (28.4%) received propofol, ten (13.5%) received fentanyl and midazolam, and three (4.1%) received etomidate. Respiratory depression was seen in 33 (44.6%) patients, including 47.5% of patients receiving methohexital, 19% receiving propofol (p = 0.008), 80% receiving fentanyl and midazolam, and 66.6% receiving etomidate. No correlation between OAA/S and ETCO2 was detected. Eleven (14.9%) patients required assisted ventilation at some point during the procedure, all of whom met the criteria for RD. Pulse oximetry detected 11 of the 33 patients with RD. Post-hoc analysis revealed that all patients with RD had an ETCO2 >50 mm Hg, an absent waveform, or an absolute change from baseline in ETCO2 >10 mm Hg. CONCLUSIONS: There was no correlation between ETCO2 and the OAA/S score. Using the criteria of an ETCO2 >50 mm Hg, an absolute change >10 mm Hg, or an absent waveform may detect subclinical RD not detected by pulse oximetry alone. The ETCO2 may add to the safety of PS by quickly detecting hypoventilation during PS in the ED.  相似文献   
117.
运动员Marfan氏综合征的医务监督   总被引:5,自引:0,他引:5  
目的 :提高教练员和医生对Marfan氏综合征的认识 ,更好地预防运动性猝死。同时为掌握身材高大项目运动员身体形态测量的规律提供参考数据。方法 :通过对 4例确诊和疑似马凡氏综合征运动员从疾病发现、发展变化、死亡、转归过程的阐述、分析 ,提供了对确诊和疑似马凡氏综合征运动员的处理、治疗方案及注意事项。同时对现役国家男、女篮球队运动员进行了包括眼科、骨科、心电图、超声心动图等全面的体检 ,以排查马凡氏综合征。结果提示 :男性运动员主动脉根部大于 60mm、女性大于 5 0mm已具有猝死风险 ,应给予高度重视。篮球运动员臂展 >身高者占4 3 3% ,且男性臂展 /身高 >1 0 3者占 2 0 %。  相似文献   
118.
AIMS: To investigate whether availability of glucometer reagents increases the frequency of self-blood glucose monitoring (SBGM) and improves glycaemic control in diabetic patients. METHODS: Sixty-two insulin-treated diabetic patients were randomized to two groups, matched for age, gender, education, income, type and duration of diabetes, years of insulin treatment, number of daily insulin injections, and haemoglobin (Hb)A1c. All patients were given a glucometer, but one group (no cost, NC) was provided glucometer test strips free of charge. The other group (control, C) had to purchase strips as they found it necessary. Both groups of patients were followed longitudinally at 2-monthly intervals for 12 months with measurement of blood glucose and HbA1c, and the frequency of SBGM was determined by downloading the glucometer memory. RESULTS: The SBGM frequency was significantly higher in the NC group vs. the C group during the first 4 months (2.0 +/- 0.2 tests/day vs. 1.4 +/- 0.1 tests/day, P<0.025). Mean HbA1c remained stable over the 12 months in the NC group, whereas an increase with time was observed in the C group. The difference in HbA1c between the two groups was significant (P<0.002) after 6 months. Random blood glucose measured at each visit and average glucose recorded by the glucometer were also lower in the NC group vs. the C group (P<0.005). There was a negative correlation between HbA1c and SBGM frequency, and HbA1c in patients testing at least twice a day was lower than in those testing less than twice a day (8.8 +/- 0.2% vs. 9.6 +/- 0.2%, P<0.001). CONCLUSIONS: In this prospective study, having easy access to glucometer strips provided free of charge to patients increased SBGM frequency. The relationship between HbA1c and SBGM frequency supports the view that SBGM is an essential tool in diabetes management.  相似文献   
119.
Twenty-four-hour blood pressure and heart rate measurements were carried out in 14 newly diagnosed diabetics and in 28 diabetics with 5–13 years' duration of the disease; 8 healthy children were used as controls. Mean arterial blood pressure increased at night in 5, decreased slightly (less than 10%) in 5 and decreased markedly (more than 10%) in 18 diabetics with longer duration of the disease. The diurnal-nocturnal differences in heart rates were significantly lower in diabetics with relative "nocturnal hypertension" compared to the control group ( p < 0.05). A significant negative correlation was found between maximal arterial blood pressure during physical exercise and the diurnal-nocturnal differences in mean arterial blood pressure in diabetics ( r =−0.58; p < 0.02). In conclusion, we found elevated nocturnal blood pressure in a subgroup of children with longer duration of diabetes and without increased albumin excretion. However, longitudinal studies of blood pressure profiles are needed to identify the candidates for diabetic vasculopathy among diabetic children.  相似文献   
120.
本文采用脑电分频积分定量法测定甜菜碱对清醒家兔脑电的影响。清醒家兔静注甜菜碱250mg/kg后,出现高幅幔波夹杂低幅快波脑电,自发脑电积分值((?)vs)显著提高。动物安静少动。结果表明甜菜碱有中枢抑制作用。  相似文献   
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