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71.
Changes in sodium, potassium, and water content in brain tissue are important in the progression of pathology that follows ischemic stroke. Determining these parameters regionally in rodent models of experimental ischemia has been limited because typical tissue weights of more than 35 mg are too large. Identifying ischemic tissue to direct tissue sampling towards ischemic cortex is also represents a difficult generally unresolved area. We suggest that larger differences between normal and ischemic cortex of sodium, potassium, and water content than previously observed can be obtained from directed sampling of 2-mg brain tissue in a model of focal cerebral ischemia. In five rats, the middle cerebral artery and both common carotid arteries were occluded for 4.9+/-0.13 h (mean+/-SEM). Punch-sampling of 1-mm diameter tissue cores for water content (H(2)O%) by the wet-dry method, and [Na(+)] and [K(+)] by flame photometry, was guided by the observation of a subtle change in the surface reflectivity of ischemic cortex of quickly dried, 20-microm frozen brain sections, that was confirmed by MAP2 immunohistochemistry. The ratio of the lesion areas as determined by the reflective change and MAP2 immunoreactivity was 0.96+/-0.03 (n=5). In ischemic cortex H(2)O% was 79.9%+/-0.8%, [Na(+)] was 550+/-25 mEq/kg dry-weight, and [K(+)] 94.2+/-19.2 mEq/kg dry-weight (n=5), all significantly different from the values in border zone cortex, and in cortex contralateral to ischemic cortex and border zone (for all samples n=60, mean wet weight 2.037+/-0.046 mg). Differences between ischemic and normal cortex were 5.4+/-1.1%, 317+/-21 mEq/kg dry-weight, -304+/-27 mEq/kg dry-weight (n=5) for H(2)O%, [Na(+)], and [K(+)]. These differences between ischemic and normal cortex are 1.4-2.5, 1-3.11, and 1.4-3.5 times greater, respectively, than previous results obtained using samples weighing 35 mg or more. These results extend the association of sodium and potassium with ischemic brain edema in the rodent model, and show that these classical measurements can keep pace with the regionality of histochemical and morphological methods.  相似文献   
72.
OBJECTIVE: The aim of this study was to evaluate the probable usefulness of normal beta-human chorionic gonadotropin (beta-hCG) regression curve in the diagnosis of persistent trophoblastic disease (PTD). METHODS: A log-value regression curve was developed from the means and 95% confidence limits of serial weekly serum beta-hCG titers of 43 patients with uneventful complete hydatidiform moles and 14 patients, who were previously confirmed as PTD. RESULTS: All 14 PTD patients (100%) had abnormal values, beyond normal range, within 4 weeks. beta-hCG was in its upper values, compared to normal regression curve at 2.29 +/- 0.19 weeks. This was earlier than plateau or rise detection at 4.21 +/- 0.33 weeks (P < 0.001). Within 3 weeks of evacuation, 13 of 14 (92.86%) PTD patients' beta-hCG values exceeded the normal range, whereas only six of 14 (42%) showed a rise or plateau. CONCLUSION: Our finding indicates that the normal beta-hCG regression curve may be useful for quicker detection of PTD than the plateau or rise of level.  相似文献   
73.
OBJECTIVES: We planned to determine whether the concentration of human chorionic gonadotropin (hCG) in cervical secretions could be a useful marker for accurate diagnosis of preterm labor, and whether the use of cervical hCG assay in combination with the Bishop score would improve the prediction of delivery within 7 days, and to determine the cut-off values for hCG in prediction of delivery within 100 h, 7 and 14 days, as well as before 35 and 37 weeks of gestation in a group of women at high risk for preterm delivery. METHODS: The study was conducted in the perinatology department of Zeynep Kamil Women and Children Diseases Education and Research Hospital between February 2002 and February 2003. One hundred and two subjects with a diagnosis of threatened preterm labor with intact membranes were included in the study. For hCG measurements, a cotton swab was rolled intracervically for 10 s to absorb fluid. Bishop scores were assessed. The correlation test was employed for the variables influencing hCG values. The ROC curve analysis was used to establish an optimal cut-off concentration for cervical hCG and an optimal cut-off level for Bishop score. The continuous variables were analyzed by the unpaired, independent, two-tailed t-test and categorical data were analyzed by the chi-square test. RESULTS: A significant positive correlation was present between the cervical hCG concentrations and Bishop scores (r=0.72, P<0.0001), and a highly negative correlation between the cervical hCG concentrations and the time interval from sampling time until delivery (r=-0.80, P<0.0001) was detected. The cut-off value for cervical hCG concentration and its sensitivity, specificity, positive and negative predictive values, accuracy, relative risk and likelihood ratio for accurate determination of delivery within 100 h were > or =32 mIU/ml, 98%, 55%, 70%, 96%, 77%, 19.68 and 2.18, respectively. However, these values were > or =32 mIU/ml, 97%, 84%, 89%, 95%, 92%, 17.37 and 6.06, respectively, for prediction of delivery within 7 days; > or =30 mIU/ml, 97%, 79%, 87%, 94%, 89%, 15.15 and 4.62, respectively, for prediction of delivery within 14 days; > or =33 mIU/ml, 89%, 92%, 94%, 83%, 90%, 5.83 and, 11.55, respectively, for prediction of delivery before 35 weeks; and finally > or =27 mIU/ml, 76%, 50%, 85%, 37%, 71%, 1.34 and 1.52, respectively, for prediction of delivery before 37 weeks. CONCLUSIONS: Cervical hCG expression seems to be rewarding in accurate diagnosis of preterm labor. This test has the advantage of low cost and wide availability.  相似文献   
74.
目的 了解影响成人疫苗接种率的有关社会经济影响因素。方法 选择广西河池市2个城镇,对5~60岁登记在册居民按有对照的组群随机抽样原则进行伤寒Vi疫苗和A群流脑疫苗的大规模接种;比较接种者的人口学和社会经济特征与接种率的关系。结果 应接种对象118071人,实际接种92476人,接种率为78.32%,其中伤寒Vi疫苗76.87%;流脑疫苗79.69%。城市接种率为77.29%,农村接种率为80.58%;5~9岁接种率最高,为89.65%;20~29岁组最低,仅为69.07%;男女接种率分别为79.07%和82.11%;高收入住户人群接种率最高达到90%左右;18~60岁人群中,按受教育程度分析以“小学毕业”人群接种率最高,为78.34%;按居住单元分析,学生的人群接种率最高,达92.01%,私营业主和退休人群接种率最低,分别为69.71%和68.82%;居住未满1年者的人群接种率最低.为62.5%.居住1~2年者接种率最高,为84.47%。结论 受教育程度、经济收入、居住年限以及城乡差别对接种率并无直接影响;流动性大、老年人是影响疫苗接种率的主要因素。  相似文献   
75.
目的根据2001年全国计划生育和生殖健康调查资料,对我国东、中、西部三大经济地区乡级计划生育服务站的技术服务提供及服务能力进行跨地区比较分析。方法全国抽样调查,采用分层、三阶段、概率比例抽样方法。对776个计划生育服务站和负责人采用观察与询问的方式进行问卷调查。结果全国农村样本点乡站放置和取出宫内节育器年均258.5例次,开展女性绝育术年均38.5例次,实施人工流产术年均29.6例次,三地区间差异有统计学意义(P<0.05)。开展男性绝育术和皮下埋植术年均分别为10.4例次和2.5例次,三地区间差异无统计学意义(P>0.05);在样本点中,95%(737/776)的乡站有B超设备,其中B超服务用于宫内节育器检查和妇科疾病诊断的乡站比例分别为69.5%(509/737)和55.0%(405/737);提供常见妇科疾病诊治、产前检查、不育症诊治的比例分别为84.1%、76.8%和25.4%,提供性病诊治比例为19.5%;提供妊娠试验、血尿便常规检查和宫颈涂片的比例分别为91.4%、18.6%和9.8%。精液检查比例为3.5%;提供短效、长效和速效口服避孕药的比例分别为95.6%、89.7%和71.3%。提供紧急避孕药的比例为24.7%。提供避孕套的比例为97.8%;能提供咨询服务的乡站比例75.6%,设有“悄悄话”室乡站的比例为52.1%;提供术后和产后随访服务的比例分别为85.4%和38.3%。结论全国农村样本点乡站在提供计划生育手术服务、发放避孕药具,以及围绕着生育、节育和不育开展力所能及的生殖保健服务方面已经具备相当能力,但各地的技术服务提供和服务能力发展并不均衡,东、中、西部地区的差别明显。表明我国基层计划生育服务站改革已是一种必然趋势,改革的方向应遵照国家人口计生委关于服务站建设的总体发展格局对乡站进行优化和整合。只有改革才能加快乡站服务能力建设,才能提高服务水平,才能适应客观需求,才能让广大农村育龄群众得到满意的服务。  相似文献   
76.
诊断性超声辐照对人早孕绒毛组织超微结构的影响   总被引:2,自引:0,他引:2  
目的 研究人早孕期经诊断性超声辐照后绒毛组织超微结构的变化。方法将35例妊娠6~8周拟行人工流产孕妇分为Ⅰ组(未行超声辐照组)、Ⅱ组(经腹部超声辐照)、Ⅲ组(经阴道超声辐照),Ⅱ组与Ⅲ组每组分为三类:5min类、10min类、15min类,各组均在辐照后24h以内取材。结果和Ⅰ组相比,Ⅱ组(15min),Ⅲ组(10min)和Ⅲ组(15min)在绒毛组织超微结构方面出现变化,尤其后者。结论诊断性超声经腹部辐照时间在15min分钟内基本上对早孕绒毛无创伤性。而经阴道超声辐照时间不宜超过10min。  相似文献   
77.
黄凯清  余琳  陈敦金 《中国妇幼保健》2006,21(20):2838-2839
目的:评价异位妊娠在MTX保守治疗过程中发生破裂出血的危险因素。方法:回顾性分析100例MTX保守治疗的异位妊娠妇女,主要测量指标为血浆HCG水平。结果:异位妊娠MTX保守治疗前、后HCG水平的上升速度与输卵管破裂出血密切相关;保守治疗给药前48 h HCG上升超过66%或给药后HCG仍持续性升高,则提示输卵管破裂可能性大;65%异位妊娠破裂出血在峡部。结论:MTX治疗前、后HCG上升的速度是预示输卵管破裂出血的良好指标;保守治疗给药前HCG上升速度超过66%/48 h或用药后HCG仍持续性升高,提示可能需要外科手术治疗;妊娠囊的着床部位也是输卵管破裂的高危因素。  相似文献   
78.
目的:探讨体外受精-胚胎移植后11天单次血β-hCG水平的临床预测价值,分析其与不同妊娠结局的关系。方法:选取胚胎移植后11天测定血清β-hCG确定妊娠并继续妊娠至12周以上的患者192例,分为无效妊娠组(包括生化妊娠、异位妊娠和妊娠早期流产)和继续妊娠组(包括单胎妊娠、双胎妊娠和三胎妊娠),比较各组间的血清β-hCG水平,分析其与各妊娠结局的关系。结果:胚胎移植后11天,无效妊娠组的血β-hCG水平为81·43±73·15U/L明显低于继续妊娠组的323·75±315·29U/L,具有显著性差异(P<0·001);单胎妊娠组血β-hCG水平均明显低于双胎妊娠组和三胎妊娠组,差异亦具有显著性(P<0·001)。当血中β-hCG介于10~50U/L时,生化妊娠和异位妊娠的阳性预测价值为81·8%,阴性预测价值达94·4%;当血β-hCG≤100U/L时,早期流产的阳性预测价值为80·8%,阴性预测价值为77·8%;当血β-hCG>250U/L时,双胎、三胎妊娠的阳性预测价值为83·3%,阴性预测价值为74·4%。结论:胚胎移植后11天单次血清β-hCG水平能有效地预测体外受精-胚胎移植周期不同的妊娠结局,具有临床指导意义。  相似文献   
79.
目的探讨隐睾患儿抗精子抗体(AsAb)与手术、绒毛膜促性腺激素(HCG)应用的相关性及术后血清雌二醇(E2)、睾酮(T)水平的变化。方法随机抽取隐睾患儿40例,分为应用HCG组(12例)及未用HCG组(28例)取腹股沟手术和正常同龄儿各20例作为对照组,检测各组血清AsAb、E2、T水平。结果各组患儿血清E2、T水平结果比较差异无统计学意义(P>0.05);在40例隐睾患儿组中IgG阳性率为53.57%,腹股沟手术组中IgG阳性率为15.00%,正常对照组无一例AsAb阳性;HCG治疗组与未用HCG治疗组AsAb阳性率比较差异无统计学意义(P>0.05)。结论隐睾患儿AsAb产生的机制可能与血睾屏障的破坏、内分泌紊乱等因素有关;应用HCG对AsAb的产生无影响。  相似文献   
80.
OBJECTIVES: To compare the performance of double screening (measuring maternal serum levels of alpha-fetoprotein [AFP] and total beta-human chorionic gonadotrophin [hCG] as markers for Down syndrome) with that of triple screening (also measuring levels of unconjugated estriol [uE3]) in the second trimester of pregnancy, and to compare ethnic variance between Chinese and Caucasian populations. METHODS: The study investigated 15096 normal singleton pregnancies and 24 pregnancies affected with Down syndrome. Frequency distributions of AFP, hCG, and uE3 levels were analyzed. Likelihood ratios (LRs) were calculated using the multiple of median value (MoM) of AFP, hCG, and uE3 as variables. After multiplying maternal age risk by the LR values for the markers used in double and triple screening, the specific risks obtained with double and triple screening were estimated. The detection rate (DR) and false-positive rate (FPR) were calculated at different cut-off points. The serum markers' levels were also compared with those of Caucasian women. RESULTS: The median MoM value of hCG was higher in women with affected pregnancies (1.40) than those with unaffected pregnancies (1.00). However, the median MoMs of AFP and uE3 (0.79 and 0.68) were lower in affected than in unaffected pregnancies. At a FPR of 5%, the detection rates reached with double and triple screening were 50% and 66.7%, respectively. Ratios of the 3 serum markers' medians to those in a study with Caucasian women were 1.06 (range=1.04-1.09) for AFP, 1.14 (range=1.10-1.17) for hCG, and 1.28 (range=1.23-1.41) for uE3 for the relevant gestational weeks. CONCLUSION: Triple screening performed better than double screening in the second trimester. Ethnic variance should be taken into account in Down syndrome screening.  相似文献   
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