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41.
Subcapital femoral osteotomies of ten young adult sheep were fixed with two bioabsorbable, self-reinforced, poly- L-lactide (SR-PLLA) lag screws of 4.5 mm in diameter. At 3 weeks radiographs were taken to check the reduction and fixation achieved. After follow-up periods of 12 weeks, 1 year and 3 years with three sheep in each group, and of 7 years and 4 months with one sheep, the sheep were killed, and the healing of the osteotomies, degradation and tissue response of the implants were examined radiographically, histologically and microradiographically. All osteotomies healed with a firm bony union. There was no dislocation or wound infection. Histologically, there was no marked tissue response in the bone tissue. At 12 weeks the implants were grossly intact, at 1 year granulation tissue and new bone formation had started to penetrate into the implant, and at 3 years the implant area was mostly replaced by connective tissue and new bone, but implant material was still seen as little islands surrounded by some lymphocytes. At 7 years and 4 months, the implant material had been degraded and replaced by tight bone. Self-reinforced poly- L-lactide lag screws seem to possess adequate mechanical properties and good biocompatibility for this demanding fixation.  相似文献   
42.
OBJECTIVE: Identification of the genetically related disorders in the putative schizophrenia spectrum is an unresolved problem. Data from the Finnish Adoptive Family Study of Schizophrenia, which was designed to disentangle genetic and environmental factors influencing risk for schizophrenia, were used to examine clinical phenotypes of schizophrenia spectrum disorders in adopted-away offspring of mothers with schizophrenia spectrum disorders. METHOD: Subjects were 190 adoptees at broadly defined genetic high risk who had biological mothers with schizophrenia spectrum disorders, including a subgroup of 137 adoptees at narrowly defined high risk whose mothers had DSM-III-R schizophrenia. These high-risk groups, followed to a median age of 44 years, were compared diagnostically with 192 low-risk adoptees whose biological mothers had either a non-schizophrenia-spectrum diagnosis or no lifetime psychiatric diagnosis. RESULTS: In adoptees whose mothers had schizophrenia, the mean lifetime, age-corrected morbid risk for narrowly defined schizophrenia was 5.34% (SE=1.97%), compared to 1.74% (SE=1.00%) for low-risk adoptees, a marginally nonsignificant difference. In adoptees whose mothers had schizophrenia spectrum disorders, the mean age-corrected morbid risk for a schizophrenia spectrum disorder was 22.46% (SE=3.56%), compared with 4.36% (SE=1.51%) for low-risk adoptees, a significant difference. Within the comprehensive array of schizophrenia spectrum disorders, schizotypal personality disorder was found significantly more often in high-risk than in low-risk adoptees. The frequency of the group of nonschizophrenic nonaffective psychoses collectively differentiated high-risk and low-risk adoptees, but the frequencies of the separate disorders within this category did not. The two groups were not differentiated by the prevalence of paranoid personality disorder and of affective disorders with psychotic features. CONCLUSIONS: In adopted-away offspring of mothers with schizophrenia spectrum disorders, the genetic liability for schizophrenia-related illness (with the rearing contributions of the biological mothers disentangled) is broadly dispersed. Genetically oriented studies of schizophrenia-related disorders and studies of genotype-environment interaction should consider not only narrowly defined, typical schizophrenia but also schizotypal and schizoid personality disorders and nonschizophrenic nonaffective psychoses.  相似文献   
43.
Reproductive-tract anomalies after administration of the potent oestrogen, diethylstilboestrol, in pregnant women raised concerns about the reproductive effects of exposure to weakly oestrogenic environmental contaminants such as bis[4-chlorophenyl]-1,1,1-trichloroethane (p,p'-DDT) or its metabolites, such as bis[4-chlorophenyl]-1,1-dichloroethene (p,p'-DDE). We measured p,p'-DDT and p,p'-DDE in preserved maternal serum samples drawn 1-3 days after delivery between 1960 and 1963. We recorded time to pregnancy in 289 eldest daughters 28-31 years later. Daughters' probability of pregnancy fell by 32% per 10 microg/L p,p'-DDT in maternal serum (95% CI 11-48). By contrast, the probability of pregnancy increased 16% per 10 microg/L p,p'-DDE (6-27). The decreased fecundability associated with prenatal p,p'-DDT remains unexplained. We speculate that the antiandrogenic activity of p,p'-DDE may mitigate harmful androgen effects on the ovary during gestation or early life.  相似文献   
44.
CONTEXT: The association of androgenic alopecia (AGA) with insulin resistance, coronary artery disease and hypercholesterolemia has been previously reported in men, but no such association has been reported in women with female androgenic alopecia (AGA). Female AGA has usually been linked with hyper-androgenism and hirsutism and, most recently, also with polycystic ovarian syndrome (PCOS), even though epidemiological documentation of the latter association is scanty. Polycystic ovarian syndrome is quite common among Caucasian women, and its association with insulin resistance is well documented. OBJECTIVES AND DESIGN: The aim of this study was to obtain a more precise estimation of the prevalence on female AGA and to describe its possible connections with insulin resistance linked parameters and with paternal and maternal family history of alopecia. A cross-sectional population based cohort survey was carried out in the City of Oulu, Finland in 1998. SETTING AND PARTICIPANTS: As a part of a population based cohort study the hair status of 324 women aged 63 years was assessed by a modification of Ludwig's scale. The background data consisting of anthropometric measures (weight, height, body mass index, waist, hip and neck circumferences), smoking status, chronic diseases and their medication as well as the family history of AGA were collected by questionnaires and interviews made by study nurses and in clinical examination. Blood samples for laboratory tests were taken on the same occasion. RESULTS: The prevalence of extensive loss of hair (at least grade II or III on Ludwig's scale) was quite high (31.2%). The insulin resistance associated parameters, such as waist and neck circumferences, abdominal obesity measured by waist-to-hip ratio, mean insulin concentration (11.3 mU/l versus 9.95 mU/l, p=0.02) or urinary albumin-to-creatinine ratio (1.80 versus 1.58, p=0.01), were significantly higher in women with extensive hair loss compared to those with normal hair or only minimal hair loss (grade I on Ludwig's scale). The women belonging to the highest quintiles of neck or waist circumferences had significantly increased risk for extensive hair loss compared to those with normal hair or minimal hair loss, the unadjusted ORs being 2.25 (95% CI, 1.26-4.03) and 1.75 (95% CI, 1.00-3.07), respectively. Similarly in women with hyperinsulinemia (fs-insulin >10 mU/l), microalbuminuria (urinary albumin-to-creatinine ratio exceeding the highest microalbuminuria decile (>2.5 mg/mmol) and paternal history of AGA the ORs for alopecia were increased being 1.65 (95% CI, 1.02-2.67), 2.39 (95% CI, 1.21-4.73) and 2.08 (95% CI, 1.26-3.44). All of these ORs, except those for highest quintiles of waist and neck circumferences remained significant in multiple adjusted models. CONCLUSIONS: According to the results of this study, female AGA (grade II or III on Ludwig's scale) was quite common among Finnish women aged 63 years. Our results support the hypothesis that women with some markers of insulin resistance have significantly increased risk for female AGA. Paternal history of alopecia seemed to be more common in female AGA compared to women with normal or minimal loss of hair.  相似文献   
45.
Background/Purpose: Laparoscopic appendectomy is an accepted way of dealing with suspected uncomplicated appendicitis in children. The role of laparoscopy in complicated acute appendicitis is more controversial. The purpose of this trial was to compare laparoscopic appendectomy with open appendectomy in children with complicated appendicitis. Methods: A total of 102 children with suspected acute appendicitis were selected randomly to undergo either a laparoscopic or an open appendectomy. The outcomes of 25 children with complicated appendicitis, 13 in the laparoscopic group and 12 in the open appendectomy group, were analyzed. Children, their parents, and research nurses were blinded to which procedure had been performed and remained blinded until the control visit 7 days after the operation. All 25 children completed a 30-day follow-up. Results: There were no differences in terms of patients' age, sex, weight, height, and appendiceal histology between the 2 groups. All laparoscopic procedures were completed without conversion. The mean ([plusmn]SD) operating time was 63 ([plusmn]31) minutes in the laparoscopic group and 37 ([plusmn]18) minutes in the open appendectomy group (mean difference 26 minutes, 95% CI 5 to 47 minutes, P = .02). There were 2 major complications in the laparoscopic group in children with appendiceal masses. One child had an entero-cutaneous fistula of the residual appendiceal tip that needed open reoperation. Another child had a pelvic abscess that resolved with antibiotic treatment. Superficial wound infections were encountered in 2 patients in the open appendectomy group. Conclusions: Laparoscopic appendectomy is an alternative to open procedure in children with complicated appendicitis. Good surgical judgement is necessary in patients with an established appendiceal abscess. J Pediatr Surg 37:1317-1320.  相似文献   
46.
Human papillomaviruses (HPVs) play the major role in cervical carcinogenesis. The authors reevaluated the role of herpes simplex virus type 2 (HSV-2) in this multistage process by conducting a longitudinal, nested case-control study using 1974-1993 data and comparing the results with those from a meta-analysis of studies. A Nordic cohort of 550,000 women was followed up for an average of 5 years, after which 178 cervical carcinoma cases and 527 controls were identified. HSV-2; HPV-16, HPV-18, and HPV-33; and Chlamydia trachomatis antibodies were determined at baseline by HSV-2 glycoprotein gG-2 and HPV virus-like-particle enzyme immunoassays and by using the microimmunofluorescence method. The relative risk of cervical carcinoma was calculated by conditional logistic regression. Longitudinal studies on HSV-2 and cervical neoplasia were identified through MEDLINE (National Library of Medicine, Bethesda, Maryland), and weighted mean relative risks were calculated. Smoking (relative risk = 1.6, 95% confidence interval (CI): 1.1, 2.3) and HPV-16/HPV-18/HPV-33 (relative risk = 2.9, 95% CI: 1.9, 4.3) were both associated with cervical carcinoma. The smoking- and HPV-16/HPV-18/HPV-33-adjusted relative risks for HSV-2 were 1.0 (95% CI: 0.6, 1.7) and 0.7 (95% CI: 0.3, 1.6), respectively, for HPV seropositives. In the meta-analysis, the relative risk for HSV-2 was 0.9 (95% CI: 0.6, 1.3). In both sets of data, HSV-2 did not play a role in cervical carcinogenesis.  相似文献   
47.
The concentration of total mercury in stimulated saliva was studied in humans with dental amalgam fillings and in 2 nonamalgam groups. The probability of exceeding the limits of mercury permitted in wastewater increased proportionally as the number of amalgam-filled surfaces increased. The mercury limit for sewage is 0.05 mg/l (= 250 nmol/l) effluent, according to the Council of European Communities directive 84/156/EEC. In neither of the nonamalgam groups was this limit exceeded, but 20.5% in the amalgam group exceeded the limit (p < .001). The risk of exceeding the limit increased 2-fold for every 10 additional amalgam-filled surfaces (odds ratio = 2.0; 95% confidence interval = 1.3, 3.3). These results demonstrate that humans, especially in populated areas, can be a significant source of mercury pollutants. As a consequence of mercury release, bacteria may acquire mercury resistance, as well as resistance to other antimicrobial agents, thus resulting in failure of antibiotic treatment.  相似文献   
48.
Employment security and health   总被引:3,自引:1,他引:2       下载免费PDF全文
OBJECTIVE: To study the relation of contractual and perceived employment security to employee health. DESIGN: Cross sectional survey. SETTING: Municipal sector employees in eight Finnish towns. PARTICIPANTS: 5981 employees with a permanent contract and 2786 employees with a non-permanent contract (2194 fixed term contract, 682 government subsidised contract). OUTCOME MEASURES: Poor self rated health, chronic disease, and psychological distress. RESULTS: Compared with permanent employees, fixed term men and women had better self rated health (men odds ratio 0.70; 95% confidence intervals 0.50 to 0.98, women 0.70 (0.60 to 0.82) and less chronic disease (men 0.69; 0.52 to 0.91; women 0.89; 0.79 to 1.02), but women had more psychological distress (1.26; 1.09 to 1.45). The only difference between subsidised employees and permanent employees was the high level of psychological distress in women (1.35; 1.09 to 1.68). Low perceived employment security was associated with poor health across all three indicators. The association of low perceived security with psychological distress was significantly stronger in permanent employees than among fixed term and subsidised employees, indicating that perceived security is more important for mental health among employees with a permanent contract. CONCLUSIONS: Contractual security and perceived security of employment are differently associated with health. It is therefore important to distinguish between these aspects of employment security in studies of labour market status and health. Such studies will also need to control for health selection, which is unlikely to operate in the same way among permanent and non-permanent employees.  相似文献   
49.
To assess the effect of different hospital types or surgical volume on the survival of ovarian cancer patients, a nationwide and population-based analysis was carried out in Finland. The study included all 3,851 ovarian cancer patients operated from 1983-94. The patients were classified according to the hospital of the first surgery. The hospitals were categorized by type (university, central or other hospital) and, separately, into quartiles by the number of operated patients (surgical volume). The patients operated at university hospitals had better survival than those operated in central hospitals, the 5-year relative survival rates (RSR) being 45% (95% CI = 42-48%) and 37% (34-40%), respectively. RSR in the 'other hospital' category was 45% (42-48%). The RSR for the patients operated in the highest volume hospitals was 47% (43-50%), and by decreasing volume (quartile) the RSR was 40% (36-43%), 40% (36-43%) and 42% (38-45%), respectively. After controlling for potential confounding by stage and age using regression models, the results remained practically the same. The results indicate that further centralizing of operative treatment of ovarian cancer may still improve survival rates on a population level in Finland.  相似文献   
50.
Background: Considerable controversy exists about the meaning of QT dispersion(QTD). The working hypothesis of the present paper was that the necessary although not sufficientcondition for the validity of QTD concept is the association of QTD with nondipolar voltage (NDPV)in T waves of the 12-lead ECG. Methods and Results: ECGs of 4890 subjects, 966 with coronary heart disease (CHD) and3844 considered CHD-free were processed using computer programs for measurement of the ratio of the first twoeigenvalues (E2/E1), nondipolar voltage (NDPV), terminal T wave direction and ECGestimate of left ventricular mass (LVM). The mean NDPV in T wave was 11 V (SD 3.9),with 6 V (SD 1.3) in terminal 40 ms. NDPV alone explained only 6% and NDPV, E2/E1 andLVM combined 13% of QTD variance. There was a modest increase in the fraction of subjects with QTD>60 ms among subjects with NDPV in terminal T > 7 V compared to those with NDPV 7 V(15% vs. 10%). A more profound increase was associated with terminal T wave directiondeviating from normal (37% vs. 12% among those with normal direction), reflectingdipolar rather than nondipolar components. Conclusions: The association between QTD and NDPV is weak, and QTD is unlikely to represent anymeaningful myocardial repolarization event in the interval domain. It seems more logical to use directmeasurement of NDPV as a potential marker of localized dispersion and heterogeneity of ventricularrepolarization for evaluation of the risk of adverse cardiac events.  相似文献   
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