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排序方式: 共有217条查询结果,搜索用时 843 毫秒
1.
Circannual variation in lymphocyte subsets, revisited 总被引:2,自引:0,他引:2
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply. 相似文献
2.
The family history in family practice: a questionnaire study 总被引:9,自引:7,他引:2
OBJECTIVES: Our aims were to investigate family medical history taking in
general practice, and to evaluate the value attached to the family medical
history as an aid to decision making in general practice. METHOD: A postal
questionnaire survey was conducted among all 291 GPs working within the
Calderdale and Kirklees Health Authority area. Each questionnaire was
followed by a reminder. The main outcome measures were answers to questions
on routine and opportunistic family history taking and a question about
transmitting knowledge about genetic risk to other members of the family.
Questions were also posed about the value attached to the family medical
history as an aid to decision making. RESULTS: A total of 193 GPs returned
the questionnaire (response rate 66.3%). On registration, 94.3% of GPs
indicated that enquiries were made about a family history of coronary heart
disease. Breast and colorectal cancer were specifically asked about by
48.4% and 30.7% of GPs, respectively. One-fifth of respondents indicated
that they asked a general question about family medical history. A little
over one-quarter of respondents indicated that they made opportunistic
enquiries about the family history or suggested that the patient should
inform other members of the family about possible risks. In the scenarios
highlighted in this study, the majority of respondents felt that the family
medical history had value as an aid to decision making. This was
particularly the case for checking a patient's cholesterol (92.1%) and for
initiating referrals in younger patients with possible cancer-related
symptoms (three-quarters of respondents). CONCLUSION: GPs value the family
medical history as an aid to decision making. Unfortunately, apart from
enquiries about coronary heart disease, routine or opportunistic family
history taking is not occurring in practice. Mechanisms need to be sought
to extract information from the family medical history so that it can be
more effectively used by GPs.
相似文献
3.
Sylvestre Marchaux Paul Fornes Stphanie Petit Catherine Poisson Didier Thevenin Thierry Le Tourneau Philippe Asseman Patrick Bruneval Pierre-Vladimir Ennezat 《Cardiovascular pathology》2008,17(4):241-243
Myocardial dysfunction without coronary involvement may occur in acute cerebral diseases. The inverted Takotsubo pattern has been recently recognized as a novel heart neurologic stress-related syndrome. We report on the case of a 40-year-old woman presenting with massive subarachnoid hemorrhage and brain death. Echocardiography revealed an extensive left ventricular circumferential akinesis except at the apex. Histologic analysis of the heart confirmed the absence of myocardial infarction and revealed only sparse foci of myocyte necrosis with contraction bands in the akinetic areas. 相似文献
4.
Pierre V Ennezat Sylvestre Maréchaux Thierry Le Tourneau Nicolas Lamblin Christophe Bauters Eric Van Belle Benjamin Gal Salem Kacet Philippe Asseman Ghislaine Deklunder Thierry H LeJemtel Pascal de Groote 《European heart journal》2006,27(6):679-683
AIMS: Functional mitral regurgitation (MR) and myocardial asynchronism occur commonly in patients with dilated cardiomyopathy and affect adversely their prognosis and symptoms. The aim of this study was to evaluate the mechanisms of changes in MR severity during dynamic exercise in patients with chronic heart failure (CHF). METHODS AND RESULTS: Seventy patients with CHF due to left ventricular (LV) systolic dysfunction [LV ejection fraction (EF) <40%] and functional MR were studied. All were in sinus rhythm. Medications were left unchanged for the study. Each patient performed a maximal symptom-limited exercise test with continuous 2D-Doppler echocardiography. Mitral regurgitant volume (RV) and effective regurgitant orifice (ERO) were determined at rest and during exercise. LV asynchrony using Doppler tissue imaging and interventricular asynchrony using conventional pulsed-Doppler were evaluated at rest. Resting LV EF averaged 25+/-8%. Mean resting LV and interventricular mechanical delays were 56+/-50 and 43+/-37 ms, respectively. The overall median values for mitral ERO and RV did not significantly change during dynamic exercise (11 [7-16] vs. 11 [6-21] mm2 and 14 [10-22] vs. 12 [9-23] mL, respectively). However, changes in mitral ERO and RV were individually variable and significantly correlated with the degree of LV asynchronism (r=0.66, P<0.0001 and r=0.66, P<0.0001, respectively). CONCLUSION: Changes in MR are variable during dynamic exercise. LV asynchronism at rest substantially contributes to worsening of functional MR during dynamic exercise in patients with CHF due to LV systolic dysfunction. 相似文献
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Alexander L Lundberg Ramon Lorenzo-Redondo Egon A Ozer Claudia A Hawkins Judd F Hultquist Sarah B Welch PV Vara Prasad James F Oehmke Chad J Achenbach Robert L Murphy Janine I White Robert J Havey Lori Ann Post 《JMIR Public Health and Surveillance》2022,8(1)
BackgroundVariants of the SARS-CoV-2 virus carry differential risks to public health. The Omicron (B.1.1.529) variant, first identified in Botswana on November 11, 2021, has spread globally faster than any previous variant of concern. Understanding the transmissibility of Omicron is vital in the development of public health policy.ObjectiveThe aim of this study is to compare SARS-CoV-2 outbreaks driven by Omicron to those driven by prior variants of concern in terms of both the speed and magnitude of an outbreak.MethodsWe analyzed trends in outbreaks by variant of concern with validated surveillance metrics in several southern African countries. The region offers an ideal setting for a natural experiment given that most outbreaks thus far have been driven primarily by a single variant at a time. With a daily longitudinal data set of new infections, total vaccinations, and cumulative infections in countries in sub-Saharan Africa, we estimated how the emergence of Omicron has altered the trajectory of SARS-CoV-2 outbreaks. We used the Arellano-Bond method to estimate regression coefficients from a dynamic panel model, in which new infections are a function of infections yesterday and last week. We controlled for vaccinations and prior infections in the population. To test whether Omicron has changed the average trajectory of a SARS-CoV-2 outbreak, we included an interaction between an indicator variable for the emergence of Omicron and lagged infections.ResultsThe observed Omicron outbreaks in this study reach the outbreak threshold within 5-10 days after first detection, whereas other variants of concern have taken at least 14 days and up to as many as 35 days. The Omicron outbreaks also reach peak rates of new cases that are roughly 1.5-2 times those of prior variants of concern. Dynamic panel regression estimates confirm Omicron has created a statistically significant shift in viral spread.ConclusionsThe transmissibility of Omicron is markedly higher than prior variants of concern. At the population level, the Omicron outbreaks occurred more quickly and with larger magnitude, despite substantial increases in vaccinations and prior infections, which should have otherwise reduced susceptibility to new infections. Unless public health policies are substantially altered, Omicron outbreaks in other countries are likely to occur with little warning. 相似文献