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81.
A novel Hendra virus variant, genotype 2, was recently discovered in a horse that died after acute illness and in Pteropus flying fox tissues in Australia. We detected the variant in flying fox urine, the pathway relevant for spillover, supporting an expanded geographic range of Hendra virus risk to horses and humans.  相似文献   
82.
Cardiac resynchronization therapy (CRT) has shown benefits in patients with severe heart failure. However, at least 30% of patients selected for CRT by use of traditional criteria (New York Heart Association class III or IV, depressed left ventricular [LV] ejection fraction, and prolonged QRS duration) do not respond to CRT. Recent studies with tissue Doppler imaging have shown that the presence of LV dyssynchrony is an important predictor of response to CRT. Phase analysis has been developed to allow assessment of LV dyssynchrony by gated single photon emission computed tomography myocardial perfusion imaging. This technique uses Fourier harmonic functions to approximate regional wall thickness changes over the cardiac cycle and to calculate the regional onset-of-mechanical contraction phase. Once the onset-of-mechanical contraction phases are obtained 3-dimensionally over the left ventricle, a phase distribution map is formed that represents the degree of LV dyssynchrony. This technique has been compared with other methods of measuring LV dyssynchrony and shown promising results in clinical evaluations. In this review the phase analysis methodology is described, and its up-to-date validations are summarized.  相似文献   
83.
COVID-19 has been sweeping the globe, hitting the United States particularly hard with a state of emergency declared on March 13, 2020. Transplant hospitals have taken various precautions to protect patients from potential exposure. OPTN donor, candidate, and transplant data were analyzed from January 5, 2020 to September 5, 2020. The number of new waiting list registrations decreased, with the Northeast seeing over a 50% decrease from the week of 3/8 versus the week of 4/5. The national transplant system saw near cessation of living donor transplantation (−90%) from the week of 3/8 to the week of 4/5. Similarly, deceased donor kidney transplant volume dropped from 367 to 202 (−45%), and other organs saw similar decreases: lung (−70%), heart (−43%), and liver (−37%). Deceased donors recovered dropped from 260 to 163 (−45%) from 3/8 compared to 4/5, including a 67% decrease for lungs recovered. The magnitude of this decrease varied by geographic area, with the largest percent change (−67%) in the Northeast. Despite the pandemic, discard rates across organ has remained stable. Although the COVID-19 pandemic continues to evolve, OPTN data show recent evidence of stabilization, an indication that an early recovery of the number of living and deceased donors and transplants has ensued.  相似文献   
84.
Prior clinical research supports the effectiveness of cancer support groups for cancer patients and their families, yet African-American families continue to be underrepresented in cancer support groups and in cancer clinical research studies. In order to fill this gap, we developed and evaluated a culturally adapted family support group for African-American families coping with parental cancer. We encountered unexpected challenges in overcoming barriers to recruitment, partnering with oncology providers, and building trust with the African-American community and African-American families coping with parental cancer. We describe actions taken during the two phases of this study and lessons learned along the way about recruiting and engaging African-American families in cancer support group studies, partnering with oncology providers, networking with the African-American community, and the importance of demonstrating cultural sensitivity to overcome the understandable historical legacy of mistrust.  相似文献   
85.
IntroductionThe purpose of this study was to investigate the impact that geographic ancestry and body size have on ultrasonographic measurements of the ulnar nerve size measured at the elbow.Materials and methodsWe performed anthropometric measurements of body size and ultrasonographic measurements of the ulnar nerve at the elbow on 13 Vietnamese and 24 European participants. Regression analysis was used to determine the effect of body size and geographic ancestry on ulnar nerve size.ResultsBMI had the greatest impact on ulnar nerve size. The short axis diameter was least resilient, and the long axis diameter was the most resilient to the effects of body size and geographic ancestry.DiscussionThe long axis diameter has an apparent immunity to the influences of overall body size, arm size, or geographic ancestry and has the most potential as a sensitive discriminator between normal nerves and nerves affected by ulnar neuropathy at the elbow.  相似文献   
86.
87.
A cohort design was used to determine uptake and drop out of 213 HIV-exposed infants eligible for Early Infant Diagnosis (EID) of HIV. To explore service providers and care givers knowledge, attitudes and perceptions of the EID process, observations and in-depth interviews were conducted. 145 (68%) infants enrolled after 2 months of age. 139 (65%) dropped out before follow up to 18 months old. 60 (43%) drop outs occurred within 2 months of enrolment. Maternal factors associated with infant drop out were maternal loss to follow up (48 [68%] vs. 8 [20%], P < 0.001) and younger maternal age (27.2 vs. 30.1 years, P = 0.033). Service providers and caregivers had inadequate training, knowledge and understanding of EID. Poverty and lack of social support were challenges in accessing EID services. EID should be more closely aligned within PMTCT services, integrated with routine mother and child health (MCH) activities and its implementation more closely monitored.  相似文献   
88.
Formaldehyde is a one-carbon, highly water-soluble aldehyde that is used in certain vaccines to inactivate viruses and to detoxify bacterial toxins. As part of the manufacturing process, some residual formaldehyde can remain behind in vaccines at levels less than or equal to 0.02%. Environmental and occupational exposure, principally by inhalation, is a continuing risk assessment focus for formaldehyde. However, exposure to formaldehyde via vaccine administration is qualitatively and quantitatively different from environmental or occupational settings and calls for a different perspective and approach to risk assessment. As part of a rigorous and ongoing process of evaluating the safety of biological products throughout their lifecycle at the FDA, we performed an assessment of formaldehyde in infant vaccines, in which estimates of the concentrations of formaldehyde in blood and total body water following exposure to formaldehyde-containing vaccines at a single medical visit were compared with endogenous background levels of formaldehyde in a model 2-month-old infant. Formaldehyde levels were estimated using a physiologically-based pharmacokinetic (PBPK) model of formaldehyde disposition following intramuscular (IM) injection. Model results indicated that following a single dose of 200 μg, formaldehyde is essentially completely removed from the site of injection within 30 min. Assuming metabolism at the site of injection only, peak concentrations of formaldehyde in blood/total body water were estimated to be 22 μg/L, which is equivalent to a body burden of 66 μg or <1% of the endogenous level of formaldehyde. Predicted levels in the lymphatics were even lower. Assuming no adverse effects from endogenous formaldehyde, which exists in blood and extravascular water at background concentrations of 0.1 mM, we conclude that residual, exogenously applied formaldehyde continues to be safe following incidental exposures from infant vaccines.  相似文献   
89.
90.
Acromegaly is a rare, chronic, and debilitating disease that results from excessive growth hormone production. Clinically, this disease is associated with enlargement of soft tissue, excessive skeletal growth, and increased risk of cardiovascular disease. Acromegaly is often diagnosed late, when a wide range of comorbidities may already be present. First-line therapy for acromegaly is typically surgery; but a number of highly-specific pharmacological agents have recently enabled a more aggressive medical management of acromegaly. Since surgical cure of acromegaly is low for macroadenomas, medical control of active acromegaly is an important component of treatment. There are no published US data currently available regarding real-world rates of comorbidities and treatment patterns among patients with acromegaly. This retrospective study examined the comorbidities and treatment patterns of 949 health plan enrollees, who had acromegaly diagnosis and/or procedure codes in an administrative claims database from July 1, 2002 through June 30, 2010. Acromegaly was associated with high rates of hypertension and diabetes along with a number of other comorbidities. The incidence of comorbidities was highest among patients with acromegaly-related treatment, which may have resulted, in part, from inadequate disease management and/or poor disease control. Unexpectedly, 55 % of patients identified with acromegaly received no treatment for acromegaly (i.e., surgery, radiotherapy, and medication) and only 28 % received a medication treatment during the observation period. However, some patients may have received a curative surgery prior to the observation period, which may have reduced the use of other acromegaly-related treatments during the study period. Of those treated with medications, the most common first medications were octreotide, cabergoline, and bromocriptine. Given the high incidence of serious comorbidities associated with active acromegaly, earlier diagnosis and treatment, along with appropriate follow-up care, may potentially avoid the life-long consequences of uncontrolled disease.  相似文献   
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