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51.
The pathogenesis of cerebral vasospasm after subarachnoid haemorrhage (SAH) involves sustained contraction of arterial smooth muscle cells that is maximal 6–8 days after SAH. We reported that function of voltage-gated K+ (KV) channels was significantly decreased during vasospasm 7 days after SAH in dogs. Since arterial constriction is regulated by membrane potential that in turn is determined predominately by K+ conductance, the compromised K+ channel dysfunction may cause vasospasm. Additional support for this hypothesis would be demonstration that K+ channel dysfunction is temporally coincident with vasospasm. To test this hypothesis, SAH was created using the double haemorrhage model in dogs and smooth muscle cells from the basilar artery, which develops vasospasm, were isolated 4 days (early vasospasm), 7 days (during vasospasm) and 21 days (after vasospasm) after SAH and studied using patch-clamp electrophysiology. We investigated the two main K+ channels (KV and large-conductance voltage/Ca2+-activated (KCa) channels). Electrophysiologic function of KCa channels was preserved at all times after SAH. In contrast, function of KV channels was significantly decreased at all times after SAH. The decrease in cell size and degree of KV channel dysfunction was maximal 7 days after SAH. The results suggest that KV channel dysfunction either only partially contributes to vasospasm after SAH or that compensatory mechanisms develop that lead to resolution of vasospasm before KV channels recover their function.  相似文献   
52.
We have examined the responsiveness of dopamine sensitive neurones in the postpartum period in woman with a history of major depression who are at high risk of experiencing a recurrence of illness in the postpartum period. Fourteen women were assessed at 36 weeks of pregnancy and during the 3 months following delivery, using the Schedule for Affective Disorders and Schizophrenia, including its change version. They were not depressed at initial assessment. Five of the 14 women went on to experience a postpartum relapse (2 major depressive disorder, 2 generalised anxiety disorder, 1 panic disorder). On the fourth day postpartum, ie before relapse, the growth hormone response to the dopamine agonist apomorphine was measured as an index of the functional state of hypothalamic dopamine D2 receptors. Women who subsequently relapsed had a significantly greater growth hormone response to apomorphine than those who remained well. This was particularly marked in women with anxiety/panic. The development of increased sensitivity of hypothalamic dopamine D2 receptors in the postpartum period appears to predict the onset of depressive and anxiety disorders.  相似文献   
53.
Maternal death associated with ovum donation twin pregnancy.   总被引:1,自引:0,他引:1  
A case of maternal death due to sub-arachnoid haemorrhage in an ovum donation twin pregnancy complicated by hypertension is described. Attention is drawn to a forecasted increase in maternal morbidity and mortality in in-vitro fertilization (IVF) pregnancies, which occur in older women and are often multiple.  相似文献   
54.
Summary The prevention of cerebral vasospasm with OKY-046, an imidazole derivative and a thromboxane synthetase inhibitor, was studied co-operatively at ten neurosurgical services. Intravenous administrations of 2, 5 or 10 /kg/minute of OKY-046 were given continuously from the earliest possible day to the 14th SAH-day to 82 pateints with ruptured cerebral aneurysm. Sixty-eight patients (83%) showed moderate to high high-density (SAH) in their initial CTs. Angiographic vasospasms were seen in 58 patients, representing 71% of all cases or 81% of the 72 cases for which angiograms were available; the vasospasms of 45 patients (55 or 63%) were moderate to severe. Symptomatic vasospasm occurred, however, only in 27 patients (33%); in 18 of those cases, moreover, the symptoms were mild or transient. The conditions of the patients at one month after the SAH were classified into 9 grades from 0 (normal) to 8 (deceased). Fifty-two patients (63%) were classified as 0 or 1, and 64 (78%) as better than 3 (possible daily life unaided). The administration of OKY-046 was proven to decrease TXB2 in the blood.This paper emphasizes the effectiveness of the drug for symptomatic vasospasm, and supports our previous contention that cerebral microthrombosis may play an important role in the pathogenesis of cerebral vasospasm.  相似文献   
55.
Summary The adenine nucleotide metabolites hypoxanthine, xanthine and uric acid were determined by high performance liquid chromatography in cerebrospinal fluid (CSF) from 25 patients with subarachnoid haemorrhage (SAH) and from 26 control subjects. In addition, the haemoglobin and protein levels in the CSF of the patients were determined.In 13 subjects, from which lumbar CSF was collected three, six and nine days after SAH, there was a gradual increase in 8 patients for hypoxanthine and in 3 of the 13 patients for xanthine and uric acid. The mean concentrations were not significantly higher than the controls. In 12 SAH patients, consecutive CSF fractions of 10 ml were collected peroperatively during surgical clipping of aneurysms. The hypoxanthine concentrations increased continously from lumbar to central CSF samples. Hypoxanthine levels were 6.5±1.0 M in lumbar CSF compared to 11.8±2.3 M in central CSF (p<0.001), while xanthine, uric acid, haemoglobin and protein levels were equally distributed. Furthermore, the SAH patients showed about 3 times higher concentrations of central CSF hypoxanthine (p<0.01) and xanthine (p<0.05) while that for uric acid was similar compared to all control subjects. Also, an in vitro study showed that the increased concentrations of the adenine nucleotide metabolites could not be caused by degradation of blood components in the subarachnoid space.It is presumed that the increased central CSF concentrations of hypoxanthine that were demonstrated in patients after SAH could be a sensitive marker for brain tissue ischaemia. However, since there was no correlation between the hypoxanthine levels, clinical condition or cerebral vascular diameter, other factors have to be excluded before ischaemia alone could explain the elevated central hypoxanthine levels in patients without major clinical dysfunction after SAH.This study was supported by grants from Karolinska Institutet, the Swedish National Society against Heart and Chest disease, The Swedish Society of Medical Sciences, Wibergs Foundation, Boehringer Ingelheim and the Swedish Medical Research Council (proj. no. 7485).  相似文献   
56.
Summary The authors describe a patient with anomalous branches of the left internal carotid artery, cross-over duplication of its middle cerebral artery and agenesis of the contra-lateral internal carotid artery associated with two aneurysms successfully clipped. Pertinent literature is reviewed.  相似文献   
57.
目的 了解妊娠期糖尿病女性产后一年内自我管理水平及影响因素,为提高妊娠期糖尿病女性产后自我管理水平、制定预防2型糖尿病的针对性策略提供参考依据。方法 2021年1月至9月按多阶段抽样方法抽取海口市5家医院205例既往有妊娠期糖尿病病史的女性进行调查。结果 产后一年内的妊娠期糖尿病女性自我管理处于低水平,得分率为59.6%;多元逐步线性回归分析结果显示,妊娠期糖尿病女性产后自我管理水平的影响因素有职业为医务人员(t=2.206,P=0.029)、文化程度(t=4.028,P<0.001)、T2DM自我感知风险(t=4.510,P<0.001)、孕期使用胰岛素情况(t=3.382,P=0.001)、产后新生儿进入NICU(t=-3.675,P<0.001)、产后行OGTT筛查(t=2.467,P=0.014)、停止母乳喂养(t=3.296,P=0.001)、产后抑郁(t=-3.684,P<0.001)及自我效能(t=5.257,P<0.001)。结论 妊娠期糖尿病女性产后一年内的自我管理水平亟待提升,其影响因素较多,医务人员应根据人群不同特征进行针对性指导,从而实现科学有效的自我管理。  相似文献   
58.
目的 探讨产后妇女盆底肌功能情况并分析造成妇女产后盆底肌损伤的相关因素,为预防妇女因生产造成盆底肌损伤提供科学依据。方法 以2019年1月至2020年11月在湖南省长沙市和株洲市各1家医院产科进行6~8周产后复查的产妇为研究对象进行资料收集及盆底肌力测定,采用描述流行病学分析方法进行盆底肌力异常情况分析,并采用单、多因素分析方法对产后妇女盆底肌异常影响因素进行分析。结果 本研究共对1 628名产妇进行调查,年龄22~38岁,平均(29.68±5.36)岁;孕次1~5次,平均孕次(2.43±1.16)次;产次1~5次,以1~2次为主,占72.4%。检出1 142例产后6~8周产妇为盆底肌力异常,异常率为70.2%。年龄30~38岁(OR=3.766)、产次≥3次(OR=2.633)、阴道分娩(OR=7.478)、孕期增重过多(OR=1.597 )及胎儿出生体重≥4 kg(OR=5.078)的产后妇女盆底肌力异常的风险较高。结论 湖南省产后妇女盆底肌力异常率较高,年龄、产次、分娩方式、孕期增重及胎儿体质量是造成产妇产后发生盆底肌损伤的重要原因,应采取相应措施,降低产后妇女发生盆底肌损伤风险。  相似文献   
59.
骆琴  彭树花  骆佳美 《华南预防医学》2021,47(12):1506-1509
目的 调查产妇产后初次泌乳时间及相关因素,为产妇产后泌乳指导工作提供参考资料。方法 以2020年1—12月在重庆市大足区2家医院住院分娩的产妇为研究对象进行问卷调查,收集产妇基本情况及喂养相关因素,并对产妇初次泌乳时间进行随访跟踪调查。采用描述流行病学分析方法对产妇产后初次泌乳时间进行分析,并采用单、多因素方法分析产妇产后初次泌乳时间的影响因素。结果 共671名产妇纳入研究,年龄21~43岁,平均(31.6±2.9)岁,其中初产妇438人,经产妇233人;胎数单胎642人,双胎29人;分娩方式阴道分娩512人,剖宫产159人。产后初次泌乳时间<24 h 329人、24~<48 h 176人、48~<72 h 105人、≥72 h 61人,分别占49.03%、26.23%、15.65%、9.09%。有序多分类Logistic回归分析显示年龄≥35岁(OR=1.895)、经产(OR=0.689)、分娩孕周≥37周(OR=0.498)、分娩方式为剖宫产(OR=1.637)、乳头凹陷/扁平(OR=2.565)、母婴同室(OR=0.520)、首次吸吮乳房时间≥30 min(OR=2.787)、每天吸吮乳房次数越多(OR=0.845)是产后初次泌乳时间的影响因素。结论 重庆市大足区产妇产后初次泌乳时间以<24 h所占比例较大,初次泌乳时间受到年龄、产次、分娩孕周、分娩方式、乳头凹陷/扁平、母婴同室、首次吸吮乳房时间、每天吸吮乳房次数多种因素影响,应当加强孕前、产前教育,鼓励阴道分娩,产后早接触、早吸吮、多吸吮促进泌乳,提高母乳喂养率,促进母婴健康。  相似文献   
60.
目的探讨旋后肩法用于肩难产产妇,对其产后盆底肌功能的改善作用。 方法选择2018年7月至2020年1月,在宁波市妇女儿童医院采用旋后肩法完成肩难产助产的28例产妇为研究对象,并纳入研究组。选取同期在本院分娩,采用耻骨联合上加压法完成肩难产助产的25例产妇纳入对照组。采用表面肌电图(sEMG),获取2组产妇分娩8周后盆底肌收缩运动肌电值。采用成组t检验,对2组产妇一般临床资料、盆底sEMG检测结果进行统计学分析。采用χ2检验,对2组产妇分娩巨大儿所占比例等进行统计学分析。本研究遵循的程序符合病例收集医院伦理委员会制定的伦理学标准,得到该委员会批准[审批文号:[2018]伦审字(28)号]。与所有受试者签署临床研究知情同意书。 结果①2组产妇身高、体重,分娩时人体质量指数(BMI)、孕龄、年龄等一般临床资料比较,差异均无统计学意义(P>0.05)。②2组产妇分娩新生儿的出生体重和巨大儿所占比例分别比较,差异亦均无统计学意义(P>0.05)。③研究组产妇前基线值、快肌收缩最大值、混合肌收缩最大值、混合肌收缩平均值、耐力肌收缩平均值、后基线值分别为(1.4±0.3) μV、(23.8±5.5) μV、(19.9±3.4) μV、(17.2±2.9) μV、(13.7±3.0) μV、(1.3±0.3) μV,均超过对照组的(1.3± 0.3) μV、(20.6±4.4) μV、(17.7±3.3) μV、(14.2±4.1) μV、(11.8±3.4) μV、(1.1±0.3) μV,并且差异均有统计学意义(P<0.05)。而2组产妇耐力肌收缩最大值比较,差异无统计学意义(P>0.05)。 结论旋后肩法用于肩难产产妇助产,较传统耻骨联合上加压法,可改善产妇产后短期内的盆底肌功能。  相似文献   
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