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排序方式: 共有499条查询结果,搜索用时 93 毫秒
21.
S Iliffe A Booroff S Gallivan E Goldenberg P Morgan A Haines 《The British journal of general practice》1990,40(336):277-279
The use by non-medical staff of a brief screening instrument (the mini-mental state examination) to detect cognitive impairment among the elderly in primary care is described. Patients aged 75 years and over registered with nine general practices in north and north west London were invited by their general practitioners to take part in the study and 1170 patients participated, a response rate of 90%. The prevalence of possible or probable cognitive impairment (score below 25 on the mini-mental state examination) was 12.8%. Six per cent of patients scored below 19, at which score a high probability of dementia exists, although less than a third of this group had a diagnosis of dementia in their medical records. There was no significant difference between men and women or by social class in the proportion of patients with low scores, but the proportion with dementia rose from 2.5% in those aged 75-79 years to 29.0% among those aged 90 years and over. Under the new general practitioner contract there is a requirement to provide annual services to the elderly, including a 'mental assessment'. In a practice with a list size of 2000 around 130 patients are likely to be aged 75 years and over. Of these around 17 would require further assessment for possible dementia on the basis of results obtained using the mini-mental state examination. 相似文献
22.
It is hypothesized that abnormal interaction between sickle hemoglobin (HbS) and erythrocyte membrane lipid might promote deposition of denatured hemoglobin (hemichrome) on the membrane. We compared the interaction of HbS and normal HbA with large unilamellar phosphatidylserine (PS) liposomes under low salt/pH conditions. Admixture of oxyHb and dioleoyl-PS resulted in loss of absorbance at 412 nm, the apparent first order rate constant for which was .25 +/- 0.02 hour-1 for HbA and .85 +/- 0.18 hour-1 for HbS. This was ascribable largely to formation of metHb and hemichromes and was accompanied by some actual transfer of heme from hemoglobin to lipid phase. By comparison, admixture of oxyHb with liposomes made from bovine brain PS having unsaturated acyl chains promoted even faster absorbance loss if the starting liposomal material contained detectable peroxidation by-product. In such cases, actual heme destruction developed with accompanying liberation of free iron and promotion of lipidperoxidation. Fluorescence quenching experiments indicate that hemoglobin/lipid interaction is characterized by very rapid initial electrostatic interaction, followed by development of irreversible changes. Similar changes still occur under conditions of physiologic salt/pH, but they develop much more slowly. The 3.4-fold faster oxidation of HbS versus HbA on lipid observed here represents an additional augmentation of the disparity in oxidation rates for hemoglobins in solution (1.7-fold faster for HbS than for HbA) observed previously. The accelerated promotion of Hb denaturation resulting from lipid contact may help explain deposits of hemichrome on sickle red blood cell membranes, particularly because these cells are in double jeopardy by virtue of having both the mutant HbS and abnormal amounts of peroxidized membrane lipid. 相似文献
23.
Fanconi anemia is an autosomal recessive disease characterized by a high risk of developing bone marrow (BM) failure and acute myelogenous leukemia. We studied growth of hematopoietic progenitor cells in long- term BM culture (LTBMC) in 8 persons with Fanconi anemia and BM failure. Although LTBMC were initiated with very few BM cells, an adherent layer formed in cultures from 7 persons. In these cultures, the number of nonadherent cells increased for 10 to 15 days. Cell growth continued until cultures were terminated at day 35 to 40. During the first 2 weeks of culture, most nonadherent cells were differentiated myeloid cells. By days 35 to 40, the adherent layer contained cells able to initiate secondary LTBMCs. These data indicate that hematopoietic precursors cells able to proliferate and differentiate in vitro are present in the BM of persons with Fanconi anemia and BM failure. They suggest that mechanisms other than absent precursor cells are responsible for BM failure in Fanconi anemia. 相似文献
24.
bcr-abl RNA in patients with chronic myelogenous leukemia 总被引:8,自引:1,他引:8
Shtivelman E; Gale RP; Dreazen O; Berrebi A; Zaizov R; Kubonishi I; Miyoshi I; Canaani E 《Blood》1987,69(3):971-973
25.
Han ZJ Lapuz C Rovenger JF Dreyfus PA Vispo BG Ou CN Luo HY Chui DH Gallivan MV 《Hemoglobin》2012,36(3):270-275
Hb Kenya is a hemoglobin (Hb) tetramer composed of two normal α- and two non α-globin chains. The latter are the product of a fusion gene in which the 5' end is (A)γ and the 3' end is β. The crossover point is between codon 81 of the (A)γ gene and codon 86 of the β gene. Like the other non α genes, the hybrid protein product ((A)γ81Leu-β86Ala) has 146 amino acids. The purpose of this report is to highlight the laboratory findings of Hb Kenya and to emphasize the pitfalls in misdiagnosis, particularly when associated with another variant such as Hb S [β6(A3)Glu→Val]. 相似文献
26.
α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价 总被引:4,自引:0,他引:4
目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。 相似文献
27.
We report a new homozygous CTG-->CCG (Leu-->Pro) mutation at codon 354 in the factor XIIIA gene of a patient suffering from FXIII deficiency. Leu354 lies in a pocket within the core domain of the FXIIIA molecule, with its side chain pointing into the structure of the barrel 1 domain. Replacement of leucine with a proline residue gives rise to steric hindrance between the proline ring and the surrounding residues, and rearrangement of these residues would be necessary for proline to be accommodated at this position. Using PCR-RFLP, we have demonstrated the absence of this mutation from 220 normal alleles. Together, these data suggest that Leu354Pro is likely to be the disease-causing mutation in this factor XIII deficient family. 相似文献
28.
Bernard MY Cheung THY Au SY Chan CM Lam SH Lau RP Lee SF Lee WS Lo EHF Sin MY Tang HH Tsang 《Experimental & Clinical Cardiology》2005,10(1):21-24
BACKGROUND:
Psychosocial stress can be the cause or the consequence of hypertension.OBJECTIVE:
To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.SUBJECTS AND METHODS:
Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.RESULTS:
The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.CONCLUSIONS:
Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong. 相似文献29.
To determine the incidence of transfusion-associated human immunodeficiency virus (HIV) infection after routine screening of donated blood, a pilot study estimated the pretransfusion prevalence of HIV infection among blood product recipients in San Francisco. Among the 911 nonduplicate pretransfusion specimens from recipients without a clinical history of acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), the overall prevalence of antibody to HIV was 2.9 percent (5.2% among males and 0.6% among females; p = 0.00002). If recipients in specifically defined or possible high-risk groups (n = 348) were excluded, a seropositivity rate of 1.8 percent (10/563) was detected, with all the positives occurring in men (10/242, 4.1%) and none in women (0/321, 0%). This demonstrated prevalence of HIV infection among blood product recipients in San Francisco before transfusion was substantially higher than the known 0.02 to 0.04 percent prevalence in the donor population. Therefore, the population of women without known risk for AIDS is the best in which to assess the risk of HIV infection in patients who are currently receiving seronegative blood transfusions. 相似文献
30.
The cytoplasmic domain of P-selectin is phosphorylated on serine and threonine residues 总被引:3,自引:2,他引:3
P-selectin is an adhesion receptor for leukocytes that is redistributed from secretory granule membranes to the surfaces of activated platelets and endothelial cells. The cytoplasmic domain of P-selectin contains two serines, two threonines, and one tyrosine that could potentially be phosphorylated. We found that P-selectin was phosphorylated in both platelets and endothelial cells and that phosphorylation rapidly increased after cell activation. Approximately 0.02, 0.05, and 0.08 mol of phosphate/mol of P-selectin were incorporated, respectively, into resting, thrombin-activated, and phorbol ester-activated platelets. Phosphorylation was completely inhibited by the protein kinase C inhibitors, staurosporine, H-7, and chelerythrine, and was enhanced by the phosphatase inhibitors, okadaic acid and calyculin-A. Phosphoamino acid analysis of 32P-labeled P-selectin showed that phosphorylation occurred predominantly on serine with lesser amounts on threonine. When expressed in transfected Chinese hamster ovary cells, P-selectin was also phosphorylated. Mutagenesis studies showed that Ser788 was the principal site of phosphorylation, with minor sites on the other serine and threonine residues of the cytoplasmic domain. Phosphorylation may regulate membrane trafficking or other functions of P-selectin. 相似文献