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991.
CD34+ fibrocytes are constitutive elements of the connective tissue where they play a role in matrix synthesis and tumor-associated stromal remodeling. Secreted protein, acidic, and rich in cysteine (SPARC) is a pivotal mediator of stromal remodeling precipitated by invasive carcinomas. The present study was undertaken to investigate CD34+ fibrocytes in the stroma of the tumor-free urinary bladder, chronic cystitis, and urothelial carcinomas together with stromal expression of α-smooth muscle actin (α-SMA), CD117, and SPARC. In tumor-free urinary bladder and chronic cystitis, CD34+ fibrocytes were found in the deep lamina propria and tunica muscularis, whereas the superficial lamina propria disclosed a CD34-negative and α-SMA-positive fibrocyte-like cell. Invasive urothelial carcinomas revealed a complete loss of CD34+ fibrocytes and concomitant appearance of α-SMA-reactive myofibroblasts which showed strong expression of SPARC. CD117 expression of tumor-free and tumor-associated stroma revealed no differences. We in this study for the first time describe CD34+ fibrocytes in the urinary bladder and an up-to-now unknown population of α-SMA-positive fibrocytes exclusively occurring in the superficial lamina propria. Stromal remodeling associated with invasive carcinomas in the urinary bladder is characterized by a loss of CD34+ fibrocytes paralleled by a gain of α-SMA-positive myofibroblasts and increased expression of SPARC.  相似文献   
992.
Progressive muscle wasting is a central feature of cancer-related cachexia and has been recognized as a determinant of poor prognosis and quality of life. However, until now, no easily assessable clinical marker exists that allows to predict or to track muscle wasting. The present study evaluated the potential of myoglobin (MG) plasma levels to indicate wasting of large locomotor muscles and, moreover, to reflect the loss of MG-rich fiber types, which are most relevant for daily performance. In 17 cancer-cachectic patients (weight loss 22%) and 27 age- and gender-matched healthy controls, we determined plasma levels of MG and creatine kinase (CK), maximal quadriceps muscle cross-sectional area (CSA) by magnetic resonance imaging, muscle morphology and fiber composition in biopsies from the vastus lateralis muscle, body cell mass (BCM) by impedance technique as well as maximal oxygen uptake (VO(2)max). In cachectic patients, plasma MG, muscle CSA, BCM, and VO(2)max were 30-35% below control levels. MG showed a significant positive correlation to total muscle CSA (r = 0.65, p < 0.001) and to the CSA fraction formed by type 1 and 2a fibers (r = 0.80, p < 0.001). However, when adjusted for body height and age by multiple regression, MG yielded a largely improved prediction of total CSA (multiple r = 0.83, p < 0.001) and of fiber type 1 and 2a CSA (multiple r = 0.89, p < 0.001). The correlations between CK and these muscle parameters were weaker, and elevated CK values were observed in 20% of control subjects despite a prior abstinence from exercise for 5 days. In conclusion, plasma MG, when adjusted for anthropometric parameters unaffected by weight, may be considered as a novel marker of muscle mass (CSA) indicating best the mass of MG-rich type 1 and 2a fibers as well as VO(2)max as an important functional readout. CK plasma levels appear to be less reliable because prolonged increases are observed in even subclinical myopathies or after exercise. Notably, cancer-related muscle wasting was not associated with increases in plasma MG or CK in this study.  相似文献   
993.
Maturation of dendritic cells (DCs) regulates protein sorting in endosomal compartments to promote the surface expression of molecules involved in T cell activation. MHC Class II complexes are mobilized to the surface via intracellular effector molecules that remain largely unknown. We here show that protein kinase C (PKC) stimulates Class II antigen surface expression, using knock-in mice that express a Class II-green fluorescent protein fusion protein as a read out. Selective inhibition of PKCdelta counteracts the ability of DCs to stimulate Class II MHC-restricted antigen-specific T cells. Activation of PKC does not affect antigen uptake, peptide loading and surface display of Class I MHC and transferrin receptor in DCs. We show that activation-induced Class II MHC surface expression is dependent on activation of PKCdelta and conclude that this event is pivotal for optimal CD4 T cell activation.  相似文献   
994.

Background

This paper reports the findings of an exploratory study about the information women diagnosed with Polycystic Ovarian Syndrome (PCOS) want to know about their condition and the consequences of this information for future treatment and health outcomes.

Methods

In-depth qualitative interviews regarding their information needs were undertaken with ten South Australian women diagnosed with PCOS. These women were aged 28–38 years and at differing stages of their fertility experience. The time since diagnosis ranged from 1–17 years. The main outcome measures sought were the identification of the information needs of women diagnosed with Polycystic Ovarian Syndrome (PCOS) during different periods of their lives; how and where they obtain this information, and the consequences of this information for future treatment and health outcomes.

Results

The women with PCOS in this study preferentially used the Internet for their information needs, as it had the advantages of convenience, privacy and accessibility, when compared with traditional mechanisms of information provision.

Conclusion

Giving a name to a collection of symptoms may bring relief and provide recognition that there really is a problem. However, with a diagnosis comes the need to have questions answered. A diagnosis of a chronic condition such as PCOS necessitates decision-making regarding possible treatment strategies and lifestyle choices. Information is needed in order to participate in shared decision making. The Internet proved to be a most versatile and beneficial source of information source for women with PCOS, if its limitations are taken into consideration.  相似文献   
995.
Objective Dental erosion is characterized as a disorder witha multifactorial aetiology including environmental acid exposure.The purpose of this article was to summarize and discuss theavailable information concerning occupational dental erosion. Methods Information from original scientific papers, case reportsand reviews with additional case reports listed in PubMed, Medlineor EMBASE [search term: (dental OR enamel OR dentin) AND (erosionOR tooth wear) AND (occupational OR worker)] were included inthe review. References from the identified publications weremanually searched to identify additional relevant articles. Results The systematic search resulted in 59 papers, of which42 were suitable for the present review. Seventeen papers demonstratedevidence that battery, galvanizing and associated workers exposedto sulphuric or hydrochloric acid were at higher risk of dentalerosion. For other industrial workers, wine tasters and competitiveswimmers, only a few clinical studies exist and these do notallow the drawing of definitive conclusions. Conclusion Occupational acid exposure might increase the riskof dental erosion. Evidence for occupational dental erosionis limited to battery and galvanizing workers, while data forother occupational groups need to be confirmed by further studies.  相似文献   
996.
OBJECTIVE: This study explored current nutritional treatment policies and nutritional outcome in patients with severe traumatic brain injury. METHODS: We performed a retrospective, structured survey of the medical records of 64 patients up to 6 months after injury or until the patients were independent in nutritional administration. RESULTS: Enteral nutrition was administered to 86% of patients. Fourteen patients (22%) had a gastrostomy; after 6 months four were still in use. At 6 months, 92% of patients received all food orally and 84% had gained nutritional independence. Energy intake was equal to the calculated basal metabolic rate throughout the first month after injury and increased by 21% during the second month. Sixty-eight percent exhibited signs of malnourishment with weight losses of 10-29%. CONCLUSION: This study suggests that most patients with severe traumatic brain injury regain their nutritional independence within the first 6 months after injury, but also that most develop signs of malnutrition.  相似文献   
997.
OBJECTIVE: To evaluate the efficacy of contact and droplet precautions in reducing the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections. DESIGN: Before-after study.Setting. A 439-bed, university-affiliated community hospital. METHODS: To identify inpatients infected or colonized with MRSA, we conducted surveillance of S. aureus isolates recovered from clinical culture and processed by the hospital's clinical microbiology laboratory. We then reviewed patient records for all individuals from whom MRSA was recovered. The rates of hospital-acquired MRSA infection were tabulated for each area where patients received nursing care. After a baseline period, contact and droplet precautions were implemented in all intensive care units (ICUs). Reductions in the incidence of hospital-acquired MRSA infection in ICUs led to the implementation of contact precautions in non-ICU patient care areas (hereafter, "non-ICU areas"), as well. Droplet precautions were discontinued. An analysis comparing the rates of hospital-acquired MRSA infection during different intervention periods was performed. RESULTS: The combined baseline rate of hospital-acquired MRSA infection was 10.0 infections per 1,000 patient-days in the medical ICU (MICU) and surgical ICU (SICU) and 0.7 infections per 1,000 patient-days in other ICUs. Following the implementation of contact and droplet precautions, combined rates of hospital-acquired MRSA infection in the MICU and SICU decreased to 4.3 infections per 1,000 patient-days (95% confidence interval [CI], 0.17-0.97; P=.03). There was no significant change in hospital-acquired MRSA infection rates in other ICUs. After the discontinuation of droplet precautions, the combined rate in the MICU and SICU decreased further to 2.5 infections per 1,000 patient-days. This finding was not significant (P=.43). In the non-ICU areas that had a high incidence of hospital-acquired MRSA infection, the rate prior to implementation of contact precautions was 1.3 infections per 1,000 patient-days. After the implementation of contact precautions, the rate in these areas decreased to 0.9 infections per 1,000 patient-days (95% CI, 0.47-0.94; P=.02). CONCLUSION: The implementation of contact precautions significantly decreased the rate of hospital-acquired MRSA infection, and discontinuation of droplet precautions in the ICUs led to a further reduction. Additional studies evaluating specific infection control strategies are needed.  相似文献   
998.
The telomere length of replicating somatic cells is inversely correlated with age and has been reported to be associated cross-sectionally with cardiovascular disease (CVD). Leukocyte telomere length, as expressed by mean terminal restriction fragment (TRF) length, was measured in 419 randomly selected participants from the Cardiovascular Health Study, comprising a community-dwelling cohort recruited in four US communities. The authors investigated associations between TRF length and selected measures of subclinical CVD/risk factors for CVD (data were collected at the 1992/1993 clinic visit) and incident CVD (ascertained through June 2002). In these participants (average age = 74.2 years (standard deviation, 5.2)), mean TRF length was 6.3 kilobase pairs (standard deviation, 0.62). Significant or borderline inverse associations were found between TRF length and diabetes, glucose, insulin, diastolic blood pressure, carotid intima-media thickness, and interleukin-6. Associations with body size and C-reactive protein were modified by gender and age, occurring only in men and in participants aged 73 years or younger. In younger (but not older) participants, each shortened kilobase pair of TRF corresponded with a threefold increased risk of myocardial infarction (hazard ratio = 3.08, 95% confidence interval: 1.22, 7.73) and stroke (hazard ratio = 3.22, 95% confidence interval: 1.29, 8.02). These results support the hypotheses that telomere attrition may be related to diseases of aging through mechanisms involving oxidative stress, inflammation, and progression to CVD.  相似文献   
999.
OBJECTIVES: A surveillance program for upper-limb work-related musculoskeletal disorders (UWMSD) based on assessment of health and risk factors was implemented between 1996 and 2000 in a large shoe factory with overall high levels for biomechanical exposure. The study aimed to identify workers with an increased risk of UWMSD incidence. METHODS: In 1996, 1997 and 2000, 166 workers filled out a questionnaire and underwent a standardized physical examination. Factors from the 1996 questionnaire (general, personal and occupational factors) associated with UWMSD incidence in 1997 were selected. The predictive role of these variables was studied with a logistic model, taking into account also gender and age. The performance of a risk score based on this model was studied in 2000, using the Wilcoxon test and ROC curves. RESULTS: In 1997, 28 incident cases of UWMSD were observed (N = 107, 26.2%). Work pace and prior history of UWMSD were the only factors significantly associated with UWMSD incidence in 1997 (respectively 33% versus 13%, P = 0.02 and 58% versus 22%, P = 0.01). Psychological distress (36% versus 21%, P = 0.10), physical fatigue (35% versus 22%, P = 0.14), repetitiveness (30% versus 18%, P = 0.17) and task precision (33% versus 21%, P = 0.16) were also included in the logistic model for 1997 UWMSD incidence. Controlling for these variables, prior history of UWMSD remained associated with incidence in 1997 (OR = 5.5, 95% CI = 1.4-21.8). In the period from 1997 to 2000, 24 incident cases were observed (N = 102, 23.5%). The risk score, based on variables from the 1997 model, was significantly higher for incident cases (median = 6 in incident cases versus 4.5 for healthy subjects, P = 0.02). ROC curves indicated that the highest agreement reached 67% for sensitivity and 59% for specificity. Among subjects who did not change their task (N = 71, 18 incident cases), performance reached 66% for specificity with the same sensitivity. CONCLUSION: These results suggest that surveillance programs of UWMSD at a company level are possible even with overall high levels for biomechanical exposure and should take into account occupational and personal factors, including prior history of UWMSD.  相似文献   
1000.
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