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101.
BACKGROUND: Whether repeat bone mineral density (BMD) measurement adds benefit beyond the initial BMD measurement in predicting fractures in older women is unknown. METHODS: We prospectively measured total hip BMD in 4124 older women (mean +/- SD age, 72 +/- 4 years) from 1989 to 1990 and again 8 years later. Incident nontraumatic hip and nonspine fractures were validated by radiology reports (>95% follow-up). In addition, spine fractures were defined morphometrically in 2129 of these women by lateral spine x-ray films from 1991 to 1992 and then again 11.4 years later. Prediction of fracture risk was assessed with proportional hazards models and receiver operating characteristic curves for BMD measures. RESULTS: Over a mean of 5 years after the repeat BMD measure, 877 women experienced an incident nontraumatic nonspine fracture (275 hip fractures). In addition, 340 women developed a spine fracture. After adjustment for age and weight change, initial and repeat BMD measurements were similarly associated with fracture risk (per unit standard deviation lower in BMD) for nonspine (hazard ratio, 1.6), spine (odds ratio, 1.8-1.9), and hip (hazard ratio, 2.0-2.2) fractures (P<.001 for all models). Areas under the receiver operating characteristic curves (AUC) revealed no significant differences to discriminate nonspine (AUC, 0.65), spine (AUC, 0.67-0.68), or hip (AUC, 0.73-0.74) fractures between models with initial BMD, repeat BMD, or initial BMD plus change in BMD. Stratification by initial BMD t scores (normal, osteopenic, or osteoporotic), high bone loss, or hormone therapy did not alter results. CONCLUSION: In healthy, older, postmenopausal women, repeating a measurement of BMD up to 8 years later provides little additional value besides the initial BMD measurement for predicting incident fractures.  相似文献   
102.
We report a seizure-related death in a patient with juvenile myoclonic epilepsy 3 months following a previous generalised tonic-clonic seizure complicated by pulmonary oedema. Seizure-related pulmonary oedema is rare but may indicate an increased susceptibility to epilepsy related death. We consider possible preventative measures for patients presenting with seizure-related pulmonary oedema.  相似文献   
103.
OBJECTIVE: Although numerous cross-sectional studies have identified herpes simplex virus type 1 (HSV-1) as an important genital pathogen, the specific sexual activities associated with HSV-1 infection are not well delineated. Our objective was to identify demographic and behavioral variables in women associated with the prevalence and acquisition of HSV-1. STUDY: From 1998 through 2000, we enrolled 1207 nonpregnant 18- to 30-year-old women from 3 Pittsburgh, Pennsylvania, area health clinics in a prospective cohort study. Serum from the women was tested each visit for the presence of type-specific HSV-1 antibodies. RESULTS: At enrollment, HSV-1 serum antibodies were detected in only 38% of women < or =20 years of age. Black race, < or =12 years education, older age, and a history of at least 5 lifetime male sex partners were independently associated with the prevalence of HSV-1. In longitudinal analyses, women who had vaginal intercourse were more likely than sexually inactive women to acquire HSV-1 (6.8 vs. 1.2 cases per 100 woman-years of follow up; P=0.05). Similarly, women who only had receptive oral sex, without vaginal intercourse, were also more likely than sexually inactive women to acquire HSV-1 (9.8 vs. 1.2 cases per 100 woman-years of follow up; P=0.04). CONCLUSIONS: Receiving cunnilingus and vaginal intercourse are important risk factors for the acquisition of HSV-1 among young women. Genital herpes prevention strategies will need to consider both the increased susceptibility for HSV-1 acquisition that young adults now have at sexual debut and the important contributions of HSV-1 to the burgeoning genital herpes epidemic.  相似文献   
104.
105.
Endothelin-1 (ET-1) and adrenomedullin (ADM) are both produced in the arterial wall, but have opposing biological actions. Evidence from experimental animals suggests a functional interaction between ET-1 and ADM. We have tested this in humans. Small resistance arteries were obtained from gluteal biopsies taken from patients with chronic heart failure (CHF) due to coronary heart disease (CHD), or with CHD and preserved ventricular function. The contractile responses to big ET-1 and to ET-1 in both sets of vessels were studied in the absence (control) and presence of ADM at 20 pmol/l (low ADM) or 200 pmol/l (high ADM), using wire myography. ADM did not affect the conversion of big ET-1 into ET-1 in vessels from patients with either CHD or CHF. Low ADM did not alter the contractile response to ET-1 in vessels from patients with CHF. Low ADM was not tested in vessels from patients with CHD, but high ADM did not affect this response in arteries from these patients. High ADM did, however, significantly reduce the vasoconstrictor effect of ET-1 in vessels from patients with CHF. The maximum response, as a percentage of the response to high potassium, was 199% (S.E.M. 25%) in the control experiments (n=14), 205% (27%) in the low-ADM (n=7) studies and 150% (17%) in the high-ADM (n=6) experiments (P<0.001). Furthermore, the Hill coefficient increased from 0.57+/-0.05 in the absence of ADM to 1.16+/-0.15 in the high-ADM experiments, indicating that ADM at 200 pmol/l specifically antagonized one receptor type in vessels from patients with CHF. We conclude that there is a one-site receptor interaction between ADM and ET-1 that is specific for vessels from patients with CHF. This functional interaction between ADM and ET-1 in resistance arteries may be of pathophysiological importance in CHF.  相似文献   
106.
In this study, alpha(1)-adrenoceptor subtypes were characterised in rat femoral resistance arteries mounted on a small vessel myograph. A-61603 was found to be more potent than noradrenaline and phenylephrine in these arteries. Brimonidine (UK 14304) could not evoke any contractile responses and the sensitivity to noradrenaline and phenylephrine was not affected by (8aR,12aS,13aS)-5,8,8a,9,10,11,12,12a,13a-decahydro-3-methoxy-12-(ethylsulphonyl)-6H-isoquino[2,1-g][1,6]-naphthyridine (RS 79948), ruling out the presence of alpha(2)-adrenoceptors. Prazosin, 5-methyl-urapidil and 2-([2,6-dimethoxyphenoxyethyl]aminomethyl)-1,4-benzodioxane (WB 4101) produced rightward shifts in the sensitivity to noradrenaline, giving pA(2) values of 9.6, 9.4 and 10.4, respectively, in agreement with the presence of alpha(1A)-adrenoceptors. (8-[2-[4-(2-Methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione (BMY 7378; 1 microM) produced a small shift in the sensitivity of noradrenaline giving a pK(B) of 7.2. In the presence of 300 nM 5-methyl-urapidil, sensitivity to noradrenaline was not further shifted by 1 microM BMY 7378. Responses to noradrenaline were unaffected by the alpha(1B)-adrenoceptor alkylating agent chloroethylclonidine (1 microM). These results suggest alpha(1A)-adrenoceptors mediate contractile responses to noradrenaline in rat femoral resistance arteries.  相似文献   
107.
BackgroundOur previous study evaluated the use of reflexology compared to progressive muscular relaxation in improving the psychological and physical profile associated with multiple sclerosis. In this paper audiotapes from the reflexology sessions have been analysed to give a picture of the nature of interaction between patients and therapists during treatment.MethodsA crossover design with two groups was chosen. Each participant received six sessions of both interventions. All reflexology sessions were recorded and the tapes transcribed and analysed.ResultsAnalysis of the available audiotapes (n = 245) revealed that reflexology provided opportunities for 48 out of the 50 participants to share worries and concerns. Recurring disclosure themes related to physical symptoms and treatment, psychological concerns, home/family worries, and work/leisure issues. Explorative analysis revealed some differences in the amount of disclosure over the weeks, between for example the participant's type of MS and time living with the diagnosis.ConclusionsReflexology appears to have created a space for patients to talk about their worries and concerns, and to receive advice and support from the nurse therapists. This work contributes to the debate about the role of the therapeutic relationship within reflexology practice.  相似文献   
108.
OBJECTIVE: Safe and effective vaginally applied microbicides could help to control the continuing spread of sexually transmitted diseases. STUDY DESIGN: This study used nonhuman primates to test the effects of multiple applications of nonoxynol 9, benzalkonium chloride, or a combination on vaginal flora and lower reproductive tract tissues. Fourteen monkeys (Macaca nemestrina) received daily vaginal applications of nonoxynol 9, benzalkonium chloride, or both for 3 to 4 days. Vaginal microflora and colposcopic observations were made at baseline and during and after completion of treatments. Cervical biopsy specimens were collected from a subset of animals. RESULTS: Cervical erythema and vaginal erythema were observed in all 3 treatment groups. Cervical papillae and epithelial disruption were present in both the nonoxynol 9 and the nonoxynol 9 plus benzalkonium chloride groups. Vaginal epithelial disruption was noted in both the benzalkonium chloride and the nonoxynol 9 plus benzalkonium chloride groups. Cervical biopsy specimens from each group revealed acute inflammatory infiltrates with occasional plasma cells and lymphoid follicles. Detection of most microorganisms, including viridans streptococci, decreased in the benzalkonium chloride and the nonoxynol 9 plus benzalkonium chloride groups. Detection of Lactobacillus species decreased in the benzalkonium chloride group. All microflora levels recovered after several days without microbicide use. CONCLUSIONS: Although nonoxynol 9 is currently the only microbicide approved for use as a spermicide in the United States, its repeated use may be detrimental to the epithelial tissues of the female reproductive tract. Benzalkonium chloride, currently approved for use in other countries, not only may damage epithelial tissues but also appears to reduce the population of potentially protective Lactobacillus species in the vagina.  相似文献   
109.
110.
Awareness or insight has been identified as a major factor in successful rehabilitation after traumatic brain injury TBI. Anecdotal evidence suggests people with TBI are more likely to be aware of residual physical disabilities, perhaps focusing on these to the exclusion of other issues in the psycho social and cognitive domains, for example. To investigate this more accurately, recovery and outcome questionnaires were administered to people with TBI and their nominated significant others, and, as appropriate, an assessment of their level of functioning was also recorded. Two and three way analyses t-tests, Kendall's and Wilcoxon's comparing these perceptions were then conducted. The results indicated a high level of agreement for basic demographic data and broad outcomes. It was found the subjects reported a lower rate of physical impairment and disability than the signifiant other or the author, suggesting that, as a group, they do not fixate on physical issues. Other areas of difference were found, such as a tendency for the significant other to perceive the subject as being more dependent in mobility and self care tasks, possibly because of their close involvement. Also the author reported more impairments, using clinical language and assessment that did not necessarilyhave meaning or significance for the other groups. There was also evidence to support the notion that there is an inherent hierarchy of needs ranging from the lower order, physiological or survival skills through to higher order, self actualizing areas. Because of the differing awareness and perceptions, care must be taken in service provision to identify the personal needs and values of each individual involved.  相似文献   
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