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41.
BackgroundThis study compared the effect of antihypertensive treatment with valsartan or ramipril on atrial fibrillation (AF) recurrence, on P-wave dispersion, (PWD) and on serum procollagen type I carboxy terminal peptide (PIP).MethodsA total of 369 mild hypertensive (systolic blood pressure (SBP) >140 and/or 90 < diastolic blood pressure (DBP) < 110 mm Hg) outpatients in sinus rhythm but with at least two episodes of AF in the previous 6 months were randomized to valsartan (n = 122), ramipril (n = 124), or amlodipine (n = 123) for 1 year. Clinic blood pressure (BP) and a 24-h electrocardiogram (ECG) were evaluated monthly. Patients were asked to report any episode of symptomatic AF and to perform an ECG as early as possible. PWD and serum PIP levels were evaluated before and after each treatment period.ResultsSBP and DBP were significantly reduced by the three treatments (P < 0.001). A total of 46 (47.4%) patients treated with amlodipine had a recurrence of AF as did 26 (27.9%) patients treated with ramipril (P < 0.01 vs. amlodipine) and 16 (16.1%) patients treated with valsartan (P < 0.01 vs. amlodipine and P < 0.05 vs. ramipril). The Kaplan-Meyer analysis showed a significant reduction of AF episodes in the valsartan group (P = 0.005 log-rank test) as well as in the ramipril group (P = 0.021), even if at a lesser degree. PWD values were significantly reduced by ramipril (-4.2 ms, P < 0.05) and even more by valsartan (-11.2 ms, P < 0.01), the difference being significant (P < 0.01). Serum PIP levels were reduced by ramipril (-49.7 mug, P < 0.001) and valsartan (-49.3 mug, P < 0.001).ConclusionsDespite similar BP lowering, valsartan and ramipril were more effective than amlodipine in preventing new episodes of AF, but the effect of valsartan was greater than that of ramipril. This could be related to the greater PWD reduction observed with valsartan.American Journal of Hypertension (2008). doi:10.1038/ajh.2008.217American Journal of Hypertension (2008); 21, 9, 1034-1039. doi 10.1038/ajh.2008.217.  相似文献   
42.
OBJECTIVES: To evaluate how angiotensin-converting enzyme (ACE) gene polymorphism is associated with perioperative blood loss in hip arthroplasty in a geriatric population. DESIGN: A case-control study of subjects consecutively undergoing total hip arthroplasty. SETTING: A department of orthopedic surgery in Italy. PARTICIPANTS: One hundred five patients, mean age +/- standard deviation 68.6 +/- 10.4, undergoing total hip arthroplasty. MEASUREMENTS: ACE gene polymorphism was analyzed using polymerase chain reaction. Decrement of hemoglobin (Hb) and hematocrit (Ht) was calculated as the difference between the preoperative and the lowest postoperative value, measured 1, 2, and 3 days after surgery. Total blood loss was calculated as the sum of intra- and postoperative blood loss. RESULTS: Patients carrying the deletion homozygous and insertion/deletion heterozygous genotypes of the ACE gene show a higher decrement of Hb (P <.01) and Ht (P <.01) and higher total blood loss (P <.007) after hip surgery than subjects carrying the insertion (II) homozygous. The role of ACE gene polymorphism seems hypertension independent. Logistic regression analysis showed that II genotype reduces total blood loss. CONCLUSIONS: This is the largest study evaluating the distribution of ACE gene genotypes in patients undergoing hip arthroplasty and the first investigating the association between bleeding and ACE gene polymorphism. Our data suggest that II genotype is associated with lower total blood loss.  相似文献   
43.
We describe a new variant of Bernard-Soulier syndrome characterized by almost normal amounts of GPIb and severely reduced GPIX and GPV. Despite surface expression, GPIbα failed to support ristocetin-induced platelet agglutination and to bind two conformation-dependent monoclonal antibodies, suggesting a qualitative defect. Sequence analysis of the gene coding for GPIX revealed a T-to-C substitution at base 1811, leading to a Leu40Pro conversion, whereas no defects were found in the coding region of the GPIbα gene. Allele-specific restriction enzyme analysis showed that the propositus and one of his sisters, both with severe bleeding diathesis, were homozygous for the GPIX mutation; the members of the family with mild bleeding diathesis and/or giant platelets in the peripheral blood were heterozygous, whereas the healthy ones were homozygous for the normal allele.
Infusion of 1-desamino-8- d -arginine vasopressin normalized bleeding time in the two severely affected patients, although it did not modify ristocetin-induced platelet agglutination or membrane expression of GPIbα, GPIX, GPIIb–IIIa and GMP-140. Moreover, in one patient, normalization of bleeding time and rise of von Willebrand factor plasma concentration did not seem to be directly related.  相似文献   
44.
Hydrogen sulfide inhibits human platelet aggregation   总被引:2,自引:0,他引:2  
Gaseous mediators such as nitric oxide (NO) play a major regulatory role in the cardiovascular system homeostasis, including platelet aggregation. Here, we investigated whether hydrogen sulfide (H(2)S), a newly recognized endogenous mediator, can affects aggregation of human platelets, using sodium hydrogen sulfide (NaHS) as H(2)S-donor. NaHS inhibited platelet aggregation induced by ADP, collagen, epinephrine, arachidonic acid, thromboxane mimetic, U46619, and thrombin. H(2)S effect was not dependent by cAMP/cGMP generation, NO production or potassium-channels opening. NaHS concentrations (up to 10 mM) did not exert toxic effects on platelet viability. The possible protective role of endogenous H(2)S in cardiovascular system is discussed.  相似文献   
45.
OBJECTIVE: A higher mortality has been reported after pneumonectomy over the age of 70. The aim of the study was to quantify the additional risk due to age after standard pneumonectomy for lung cancer by a case-control study. METHODS: Our clinical database was reviewed to search for patients aged 70 years or more who underwent standard pneumonectomy for lung cancer between 1998 and 2005. A control group of patients younger than 70 (one case/two controls) was matched for sex, cardiovascular disease, American Association of Anaesthetists score, respiratory function, side of pneumonectomy, induction chemotherapy and stage. Overall mortality and morbidity were compared. Long-term survival data were also analysed. RESULTS: During the considered period, 35 patients aged 70 years or more underwent pneumonectomy (30 males, median age 73 years, 15 right-sided procedures). The control group was composed of 70 patients. The two groups were homogeneous in the variables used for matching. Overall mortality and morbidity were 11.4 and 54.2% in the elderly group as compared to 4.3 and 41.6% in controls (p-value not significant). Elderly patients experienced a higher rate of respiratory complications (25.7%) as compared to controls (8.3%, p=0.01). At univariate analysis, the only risk factor for death was the occurrence of respiratory complications (OR 6.5, CI 1.8-18.2). At multivariate analysis, age >or=70 years (OR 5.36, CI 1.48-19.3) and preoperative chemotherapy (OR 7.65, CI 2.04-28.6) were confirmed as predictors of respiratory complications. Five-year survival was 17.5% in the elderly group and 53.6% in the control group (p=0.003). Elderly patients with a better respiratory function (FEV1>70%) had a 5-year survival of 45.4%. CONCLUSIONS: In the elderly patients, the risk of respiratory complications after pneumonectomy is increased as compared to younger patients with equivalent respiratory function. Age and preoperative chemotherapy are independent risk factors for respiratory complications. A lower mortality and a better long-term survival are obtained in elderly patients with a better respiratory function (FEV1>or=70%).  相似文献   
46.
IntroductionChlamydia trachomatis (Ct) genital infection has been related to several diseases in young sexually active women. It could be related to their sexual quality of life.AimTo assess whether genital Ct infection can induce sexual function alterations in women.MethodsNine hundred ninety‐eight women (mean age 29.4, range 18–43) attending our Sexually Transmitted Disease Centre were enrolled in this observational case‐control study. All participants were clinically and microbiologically investigated due to their sexual relationships with a subject affected by chronic bacterial prostatitis. All participants underwent microbiological cultures, DNA and antibodies evaluation for common bacteria and Ct on vaginal swab and urine samples. They completed the Female Sexual Function Index [FSFI] questionnaire. On the basis of microbiological investigation results, all patients were split into three groups: Group A—genital Ct infection, Group B—genital common bacteria/yeast infection, and Group C—negative for Ct and bacteria/yeast infection.Main Outcome MeasuresFSFI questionnaire.ResultsTwo hundred ninety‐one women were classified in Group A, 276 in Group B, and 431 in Group C. Group A patients were statistically, significantly different from Group B and Group C patients in terms of pain during sexual intercourse and sexual satisfaction. Group C patients had significantly higher FSFI scores (27.1 ± 1.3) (P < 0.001) for both desire (4.9 ± 1.0) and lubrication domain (3.8 ± 1.1) (P < 0.001, P < 0.003, respectively) when compared with Group A patients. Multivariate analysis demonstrated that negative Ct infection marker in female patients must be considered as an independent prognostic factor in predicting a subsequent optimal FSFI questionnaire score (P = 0.002).ConclusionsPositive values of Ct infection markers are associated with lower FSFI scores for sexual desire, lubrication, and overall sexual function. Genital Ct infection could induce pain during sexual intercourse, reducing sexual satisfaction and sexual quality of life in young sexually active women. Cai T, Mondaini N, Migno S, Meacci F, Boddi V, Gontero P, Malossini G, Geppetti P, Mazzoli S, and Bartoletti R. Genital Chlamydia trachomatis infection is related to poor sexual quality of life in young sexually active women.  相似文献   
47.
48.
49.
  总被引:8,自引:0,他引:8  
Endogenous nitric oxide is an ubiquitous gaseous molecule that regulates many aspects of human airway biology including the modulation of airway and vascular smooth muscle tone. It is generated from the three different enzymes nitric oxide synthases (NOS) -1, -2 and -3 which are all expressed in pulmonary cells. NOS-1 is localised primarily to neuronal structures, where NO is a mediator of the inhibitory Non-Adrenergic Non-Cholinergic System and NOS-3 is present in endothelial cells. While these enzymes are constitutively expressed, NOS-2 is an inducible enzyme independent of calcium and highly induced in inflammatory diseases such as allergic asthma, where NO may act beneficial or deleterious depending on the site of and amount of generation. The use of NO-donor compounds or classical unselective NOS inhibitors did not lead to significant therapeutical effects in asthmatic patients. Insights on the precise role of NO in asthma can only be achieved by targeting NO generation selectively. More potent and selective NOS-2 inhibitors have to clarify a role of NOS-modification based therapy in clinical routine. NO can also be detected in the exhaled air. Increased levels of exhaled NO in asthmatic patients may be useful for a non-invasive determination of airway inflammation.  相似文献   
50.
Bakakas are native Bantus belonging to the Mbo-Bakossi group, peopling the Cameroon's Littoral region. In the context of a wide bio-anthropological study project focused on the bio-historical processes involved in the areas, 278 adults of both sexes from the villages of Ebone and Bakwat (Bakaka Canton) were investigated for 14 erythrocyte and serum genetic polymorphisms (ACP1, ADA, EsD, GLO, Hb beta, GPX1, CAII, PGM1, SAHH, 6-PGD, Hp, Pi, Gc and Tf). With only a few exceptions (Hp and GLO systems), the genetic frequencies of the polymorphisms considered tend to fall within the range of variation known for the subsaharan populations. With reference to the malaria endemicity characterizing the Littoral environment, high frequencies for Hb beta*S allele and absence of the ACP1*R 'Negro allele' were recorded. The genetic distances among Bakakas and 14 other Central African populations were also calculated from six genetic loci.  相似文献   
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