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41.
Influenza virus infections are associated with a significant number of illnesses and deaths on an annual basis. Many of the deaths are due to complications from secondary bacterial invaders, including Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pyogenes. The β-hemolytic bacteria S. pyogenes colonizes both skin and respiratory surfaces, and frequently presents clinically as strep throat or impetigo. However, when these bacteria gain access to normally sterile sites, they can cause deadly diseases including sepsis, necrotizing fasciitis, and pneumonia. We previously developed a model of influenza virus:S. pyogenes super-infection, which we used to demonstrate that vaccination against influenza virus can limit deaths associated with a secondary bacterial infection, but this protection was not complete. In the current study, we evaluated the efficacy of a vaccine that targets the M protein of S. pyogenes to determine whether immunity toward the bacteria alone would allow the host to survive an influenza virus:S. pyogenes super-infection. Our data demonstrate that vaccination against the M protein induces IgG antibodies, in particular those of the IgG1 and IgG2a isotypes, and that these antibodies can interact with macrophages. Ultimately, this vaccine-induced immunity eliminated death within our influenza virus:S. pyogenes super-infection model, despite the fact that all M protein-vaccinated mice showed signs of illness following influenza virus inoculation. These findings identify immunity against bacteria as an important component of protection against influenza virus:bacteria super-infection.  相似文献   
42.
This study examined the influence of hypnotizability and absorption on psychological and autonomic responses to an experimental stressor and a relaxation procedure of 13 high and 13 low hypnotizable subjects. Heart-rate variability was the measure of autonomic reactivity. Absorption was found to be the only significant predictor of autonomic reactivity in both experimental conditions. Expectation and previous relaxation training, but not absorption or hypnotizability, predicted perceived relaxation in the relaxation condition. The results suggest that in a nonhypnotic context the influence of hypnotizability on responses to experimental conditions may be less prominent than the influence of absorption. Absorption may be associated with greater awareness of internal physical and psychological processes, and the results support previous clinical findings of positive correlations between absorption, subjective perception of autonomic arousal, and somatic symptom reporting.  相似文献   
43.
44.
Abstract Thirty consecutive patients with bleeding oesophageal varices secondary to schistosomal liver disease received injection sclerotherapy. These formed a part of a prospective study, to evaluate the role of sclerotherapy in the treatment of bleeding oesophageal varices due to different aetiological factors in patients seen at the Gastroenterology Unit, Riyadh Armed Forces Hospital, Saudi Arabia, between December 1980 and July 1984.
Schistosomiasis is endemic in parts of Saudi Arabia. Sclerotherapy has a special place in schistosomal liver disease as liver function is well preserved in this disease. The new antischistosomal drugs are effective and may halt the progress of the disease. However, in many patients portal hypertension with bleeding oesophageal varices is found at diagnosis. Of the patients with schistosomiasis, 63.3% were Group A Child's Classification. Oesophageal varices have been eradicated in 11 cases during the mean follow-up period of 28 months (range 3-44 months). Four patients were referred for surgery because of bleeding gastric varices, two of whom died following operation. One patient, who was also hepatitis B surface antigen positive, died due to re-bleeding from gastric varices. The remaining 25 patients had no recurrence of bleeding and their liver function remained satisfactory.
Surgical procedures for oesophageal varices in schistosomiasis carry the risk of peri-operative and postoperative morbidity and mortality. In contrast, complications following sclerotherapy are minor compared to surgical procedures and none of our patients had any serious sclerotherapy complications.  相似文献   
45.

Background & aims

Long-term adherence to conventional weight-loss diets is limited while intermittent fasting has risen in popularity. We compared the effects of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk factors in adults with abdominal obesity and ≥1 additional component of metabolic syndrome.

Methods & results

In total 112 participants (men [50%] and women [50%]) aged 21–70 years with BMI 30–45 kg/m2 (mean 35.2 [SD 3.7]) were randomized to intermittent or continuous energy restriction. A 6-month weight-loss phase including 10 visits with dieticians was followed by a 6-month maintenance phase without additional face-to-face counselling. The intermittent energy restriction group was advised to consume 400/600 kcal (female/male) on two non-consecutive days. Based on dietary records both groups reduced energy intake by ~26–28%. Weight loss was similar among participants in the intermittent and continuous energy restriction groups (8.0 kg [SD 6.5] versus 9.0 kg [SD 7.1]; p = 0.6). There were favorable improvements in waist circumference, blood pressure, triglycerides and HDL-cholesterol with no difference between groups. Weight regain was minimal and similar between the intermittent and continuous energy restriction groups (1.1 kg [SD 3.8] versus 0.4 kg [SD 4.0]; p = 0.6). Intermittent restriction participants reported higher hunger scores than continuous restriction participants on a subjective numeric rating scale (4.7 [SD 2.2] vs 3.6 [SD 2.2]; p = 0.002).

Conclusions

Both intermittent and continuous energy restriction resulted in similar weight loss, maintenance and improvements in cardiovascular risk factors after one year. However, feelings of hunger may be more pronounced during intermittent energy restriction.
46.
Speckle tracking echocardiography is an emerging technique, which is currently being included in clinical guidelines. We sought to investigate the impact of transducer frequency settings on speckle tracking derived measures. The study comprised of 22 subjects prospectively enrolled for a randomized controlled trial (LOOP-study, Clinicaltrials.gov:NCT02036450). Patients were above 70 years of age with increased risk of stroke, and had an echocardiogram performed, which included focused images of the left ventricle. Focused images were obtained with the transducer frequency set at both 1.7/3.3 and 1.5/3.0 MHz. The images were obtained immediately after each other at the exact same position for the two settings. Speckle tracking was performed in three apical projections, allowing for acquisition of layered global longitudinal strain (GLS) and strain rate measures. Concordance between the frequency settings was tested for endo-, mid-, and epicardial GLS and strain rates by coefficients of variation, bias coefficients and visually displayed by Bland–Altman plots. Bland–Altman plots did not reveal any significant over- or underestimation of any speckle tracking measure. Bias coefficients showed that none of the measurements differed significantly between the two settings (bias for GLSendo?=???0.07?±?2.94, p?=?0.91; GLSmid?=?0.02?±?2.70, p?=?0.98, GLSepi?=?0.07?±?2.53, p?=?0.90). Coefficients of variation were as follows: GLSendo?=?15.11%, GLSmid?=?15.28%, GLSepi?=?17.26%, systolic strain rate?=?15.66%, early diastolic strain rate?=?38.46%, late diastolic strain rate?=?11%. Changing between transducer frequency settings does not systematically derange speckle tracking measures. One can safely reduce the transducer frequency without compromising the validity of speckle tracking derived measures.  相似文献   
47.
A 21-years-old with Down syndrome presented with respiratory distress. Initial investigations revealed a cardiac tamponade. On further evaluation, he had positive coronavirus disease-2019 (COVID-19), severe chest infection and severe hypothyroidism. He responded well to urgent pericardiocentesis, levothyroxine, hydrocortisone and tocilizumab.  相似文献   
48.
Based on extensive clinical and clinical chemical information (107 different items) from 1002 jaundiced patients, we developed a diagnostic algorithm which was evaluated on a test sample of another 110 jaundiced patients. A primary classification into categories of obstructive jaundice (probability of obstruction greater than or equal to 0.80), non-obstructive jaundice (probability of obstruction less than or equal to 0.20), and of doubtful causes of jaundice (probability of obstruction: 0.20-0.80) was attempted. Among 234 patients in the data base who were classified as obstructive, 220 (94%) proved to be so, as did 36 (97%) of 37 in the test sample. The corresponding figures for non-obstructive jaundice were 463 (96%) of 483 patients correctly classified in the data base and 47 (92%) of 51 patients in the test sample. Altogether 69% of the patients in the data base and 75% of those in the test sample were correctly classified, in 27% and 20% the cause of jaundice was doubtful, and only 4% and 5%, respectively, were misclassified. A slight majority of the patients in whom the algorithmic diagnoses were doubtful proved obstructive. A close correlation was found between the preliminary diagnoses made by the algorithm and by the clinicians. A secondary classification of the patients by the algorithm into benign versus malignant causes of obstructive jaundice performed equally well in the data base and the test sample.  相似文献   
49.
Studies indicate that deficient skeletal muscle mass or sarcopenia is a major cause of disability and morbidity among the elderly. In part, due to the lack of generally applicable normal values, there is still insufficient epidemiologic data available on the frequency and severity of sarcopenia in health and under various disease-related conditions. The objectives of the present study were to (1) characterize the age- and menopause-related variations in appendicular lean tissue mass (LTM(A)), (2) provide young-normal means and estimate the age-specific prevalence of sarcopenia among healthy women. A total of 754 healthy women were included in the study of cross-sectional design. LTM(A) was estimated by dual-energy x-ray absorptiometry (DEXA). Physical characteristics and menopausal status were also registered. LTM(A) as well as height showed significant negative correlation with age with Pearson's r values of -0.43 and -0.06, respectively (P <.05). Trend of finding lower mean values with advancing age remained even when LTM(A) was adjusted for height(2) (ht(2)). Menopause did not seem to have any influence on LTM(A). Young-normal means were obtained from 216 premenopausal women aged 18 to 39 years. Prevalence rates of sarcopenia in healthy women were determined with reference to a cut-off line corresponding to LTM(A) or LTM(A)/ht(2) less than young-normal mean 2 SD and were found to be 40.2% and 12.3%, respectively, among the healthy elderly (>70 years of age). Results of the present study provide further evidence that sarcopenia exists even among otherwise healthy women with increasing age-specific prevalence. Further studies are needed (1) to estimate the prevalence of sarcopenia under various health and disease-related conditions with reference to the hereby given cut-off values and (2) to find therapeutic strategies with beneficial effects in conserving skeletal muscle mass.  相似文献   
50.
Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3- dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5.  相似文献   
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