全文获取类型
收费全文 | 5276篇 |
免费 | 103篇 |
国内免费 | 47篇 |
专业分类
5426篇 |
出版年
2023年 | 10篇 |
2022年 | 9篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 17篇 |
2014年 | 15篇 |
2013年 | 12篇 |
2012年 | 569篇 |
2011年 | 604篇 |
2010年 | 140篇 |
2009年 | 86篇 |
2008年 | 450篇 |
2007年 | 493篇 |
2006年 | 448篇 |
2005年 | 380篇 |
2004年 | 342篇 |
2003年 | 356篇 |
2002年 | 258篇 |
2001年 | 177篇 |
2000年 | 231篇 |
1999年 | 73篇 |
1998年 | 23篇 |
1997年 | 21篇 |
1996年 | 14篇 |
1995年 | 20篇 |
1994年 | 31篇 |
1993年 | 17篇 |
1992年 | 26篇 |
1991年 | 28篇 |
1990年 | 34篇 |
1989年 | 37篇 |
1988年 | 45篇 |
1987年 | 33篇 |
1986年 | 32篇 |
1985年 | 34篇 |
1984年 | 23篇 |
1983年 | 25篇 |
1982年 | 13篇 |
1981年 | 26篇 |
1978年 | 15篇 |
1965年 | 26篇 |
1964年 | 11篇 |
1963年 | 14篇 |
1959年 | 7篇 |
1958年 | 28篇 |
1957年 | 17篇 |
1956年 | 18篇 |
1954年 | 7篇 |
1953年 | 9篇 |
1951年 | 8篇 |
排序方式: 共有5426条查询结果,搜索用时 15 毫秒
221.
Chronic fatigue syndrome (CFS) is an important condition confronting patients, clinicians, and researchers. This article provides information concerning the need for appropriate diagnosis of CFS subtypes. We first review findings suggesting that CFS is best conceptualized as a separate diagnostic entity rather than as part of a unitary model of functional somatic distress. Next, research involving the case definitions of CFS is reviewed. Findings suggest that whether a broad or more conservative case definition is employed, and whether clinic or community samples are recruited, these decisions will have a major influence in the types of patients selected. Review of further findings suggests that subtyping individuals with CFS on sociodemographic, functional disability, viral, immune, neuroendocrine, neurology, autonomic, and genetic biomarkers can provide clarification for researchers and clinicians who encounter CFS characteristically confusing heterogeneous symptom profiles. Treatment studies that incorporate subtypes might be particularly helpful in better understanding the pathophysiology of CFS. This review suggests that there is a need for greater diagnostic clarity, and this might be accomplished by subgroups that integrate multiple variables including those in cognitive, emotional, and biological domains. 相似文献
222.
Long-term social isolation of laboratory animals is a model to study the behavioral and neurochemical consequences of the absence of social interaction in rodents. Many of the symptoms induced by isolation resemble depression and anxiety disorder symptomatology. Our studies have revealed that male mice socially isolated for more than 4 weeks, exhibit increased aggressiveness, a reduced responsiveness to GABA(A) receptor acting drugs, and a downregulation of brain levels of 3alpha,5alpha-tetrahydroprogesterone (allopregnanolone: 3alpha,5alpha-THP), a neurosteroid endowed with potent positive allosteric modulatory activity of the action of GABA at various GABA(A) receptor subtypes. This downregulation of 3alpha,5alpha-THP appeared to be associated with the reduction of brain type I 5alpha-reductase mRNA and protein expression. Systemic administration of the selective serotonin reuptake inhibitor fluoxetine and its metabolite norfluoxetine normalized brain 3alpha,5alpha-THP content and reduced responsiveness to GABA(A) mimetic drugs in a stereospecific manner. These drugs in nanomolar doses also reduced social isolation-induced aggressiveness with the same stereospecificity as detected in their action on 3alpha,5alpha-THP brain content, while their ex vivo inhibition of serotonin reuptake occurred at high micromolar doses and lacked stereospecificity. From these results we infer that the brain 3alpha,5alpha-THP content physiologically upregulates GABA(A) receptor responsiveness to GABA and that social isolation induces a reduction of brain 3alpha,5alpha-THP content that is probably causally related to the onset of aggression. 相似文献
223.
Doctor's Expertise and Managing Discrepant Information from Other Sources in Genetic Counseling: A Conversation Analytic Perspective 总被引:1,自引:0,他引:1
The study examines a recurrent interactional pattern in genetic counseling. It describes clinical geneticists' responses in
situations in which clients have presented information from other sources that is potentially discrepant with information
given by the doctor. The data consists of 12 video-recorded sessions of genetic counseling in Finland, and the method is conversation
analysis. There are two primary ways the doctors respond: either they accept the client's information as such, but show that
it is not discrepant with the doctor's information, or they reject the client's information. In the latter case they mitigate
the ‘wrongness’ of the client's information. The clinical geneticists seem to be working with a dilemma: they need to find
a balance between ensuring correct understanding of the information and showing respect for the expertise of others. A particularly
complex case is also analyzed and reflected on. 相似文献
224.
Claes E Evers-Kiebooms G Denayer L Decruyenaere M Boogaerts A Philippe K Legius E 《Journal of genetic counseling》2005,14(5):349-363
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34
noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer
than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No
differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and
ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically
elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest
while general distress remained about the same. There were no significant changes in distress in the group of carriers except
for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects
of predictive testing when offered in the context of a multidisciplinary approach. 相似文献
225.
Differences in Individual Approaches: Communication in the Familial Breast Cancer Consultation and the Effect on Patient Outcomes 总被引:1,自引:0,他引:1
This multicenter study aimed to assess (i) whether individual clinical geneticists and genetic counselors vary in their communication skills and (ii) whether this variation in communication impacts on patient outcomes, such as anxiety, depression, genetics knowledge, and satisfaction. One hundred and fifty women from high-risk breast cancer families attending their first genetic counseling consultation completed pre and post-consultation self-report questionnaires. The consultations were audiotaped and transcribed verbatim. Univariate analyses showed highly significant differences between individual clinical geneticists and genetic counselors in: facilitating understanding (p 0.001); facilitating active involvement (p 0.001); facilitating partnership building (p = 0.003); addressing emotional concerns (p 0.001); and discussing prophylactic mastectomy (p = 0.017). Multivariate linear regressions showed that this variation in communication resulted in a greater change in patients depression 4 weeks after the counseling session (p = 0.017). These findings suggest clinical geneticists and genetic counselors have achieved some standardization in communicating information, but showed diversity in their facilitation skills. Communication skills may be a useful area to explore further in this field. 相似文献
226.
Evaluating Genetic Counseling: Client Expectations,Psychological Adjustment and Satisfaction with Service 总被引:1,自引:0,他引:1
Periodic evaluations of genetic counseling services are useful for determining the effectiveness of counseling in meetings its psycho-educational aims, as well as identifying where improvements to the service may be made. This study aimed to evaluate the genetic counseling services provided by Genetic Services of Western Australia (GSWA) to determine the impact of counseling on client expectations, satisfaction with the service, and psychological adjustment, defined as wellbeing and perceived personal control (PPC). A total of 122 clients participated in a self-administered survey conducted pre- and post-counseling. Client expectations of the service as a means of providing information were met, and opportunities for counselors to meet client’s expectations of psychological support were identified. Furthermore, counseling was found to maintain and enhance psychological wellbeing of clients. The role of counseling in facilitating the development of PPC was a key contributor to a high sense of satisfaction in clients. 相似文献
227.
To investigate the contested role of notional number in English subject-verb agreement, we used a sentence completion task
to examine agreement with minimally different subject noun-phrases, such as the gang on the motorcycles and the gang near
the motorcycles. These contrasting phrases biased different notional construals of collective nouns, such as gang, which are
normally ambiguous between plural (distributed) and singular (collected) construals. With subjects biased toward spatial distribution,
such as gang on motorcycles, more plural verbs occurred in speakers’ sentence completions than in sentence completions with
a bias toward spatial collection such as gang near motorcycles. This offers strong evidence regarding both the existence and
the magnitude of notional effects on subject-verb number agreement in English. 相似文献
228.
Masand PS Culpepper L Henderson D Lee S Littrell K Newcomer JW Rasgon N 《CNS spectrums》2005,10(10):suppl14 1-suppl1415
Patients with psychiatric disorders have an increased rate of cardiovascular morbidity and mortality compared with the general population. Metabolic issues such as weight gain, dyslipidemia, diabetes mellitus, diabetic ketoacidosis,and pancreatitis have been reported with the use of antipsychotic agents. Although atypical antipsychotics have not been linked directly to the development of metabolic syndrome, these medications have been shown to increase risk factors that can lead to metabolic and endocrine disturbances. Therefore, clinicians should provide ongoing monitoring for patients who are being treated for psychiatric disorders with these agents. According to the 2004 Consensus Report on Antipsychotics, screening measures should include baseline and follow-up monitoring of personal/family histories, weight (body mass index), waist circumference, blood pressure, fasting plasma glucose, and fasting lipid profile. 相似文献
229.
Neurons were found in the rhesus macaque anterior orbitofrontal cortex that respond to novel but not to familiar visual stimuli. Some of these neurons responded to all novel stimuli, and others to only a subset (e.g., to novel faces). The neurons have no responses to familiar reward- or punishment-associated visual stimuli, nor to taste, olfactory or somatosensory inputs. The responses of the neurons typically habituated with repeated presentations of a novel stimulus, and five presentations each 1s was the median number for the response to reach half-maximal. The neurons did not respond to stimuli which had been novel and shown a few times on the previous day, indicating that the neurons were involved in long-term memory. The median latency of the neuronal responses was 120 ms. The median spontaneous firing rate was 1.3 spikes/s, and the median response to novel visual stimuli was 6.0 spikes/s. These findings indicate that the long-term memory for visual stimuli is information that is represented in a region of the primate anterior orbitofrontal cortex. 相似文献
230.