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81.
82.
AIM: To investigate the effect of atorvastatin on the development of heart failure after myocardial infarction and the association with sodium-calcium exchanger (NCX) expression.METHODS: The model of heart failure was established by ligation of the anterior descending coronary artery for 8 weeks. The rats were randomly divided into control group, heart failure group, and atorvastatin group. Either atorvastatin (10 mg·kg-1·d-1) or vehicle was orally administered to the rats on the next day after the surgery. The left ventricular function and NCX expression were analyzed 8 weeks after ligation. Neonatal rat cardiomyocytes were cultured to investigate the effect of atorvastatin on the changes of calcium concentration induced by hypoxemia.RESULTS: A decrease in left ventricular diastolic dimension, an increase in left ventricular fractional shortening, and reductions of BNP level and NCX expression were observed in atorvastatin group. The hypoxemia-induced calcium overload in cultured cardiomyocytes was inhibited by atorvastatin, and it was inhibited by the inhibitor of NCX.CONCLUSION: Atorvastatin treatment improves cardiac function, which may be related to the expression and function of sodium calcium exchanger in heart failure.  相似文献   
83.
AIM: To explore the changes and the mechanism of heart functions in the rats with spleen-qi deficiency syndrome. METHODS: The rats were randomly divided into blank control group and spleen-qi deficiency model group. The changes of cardiac functions in the rats were determined by ultrasonic imaging with a high-resolution in vivo imaging system. HE staining was used to observe the pathological changes. The protein expression of brain natriuretic peptide (BNP) in the myocardium was assessed by Western blotting. The contents of BNP and cAMP in the serum and myocardium were measured by ELISA. The mRNA expression of basic fibroblast growth factor (bFGF) and protein kinase A (PKA) was detected by real-time PCR. RESULTS: Compared with blank control group, the myocardial cells in the model group had different degrees of necrosis and degeneration. Stroke volume and ejection fraction were decreased. The contents of cAMP and BNP in the serum and myocardium were increased in model group. The protein expression of BNP and the mRNA expression of bFGF and PKA were also increased.CONCLUSION: Spleen-qi deficiency syndrome causes heart function decline in rats. The expression of BNP, cAMP, PKA and bFGF is all increased.  相似文献   
84.

Objectives

Plasma atrial natriuretic peptide (ANP) levels have been reported to be elevated in cats with cardiomyopathy. We investigated the diagnostic accuracy of plasma ANP concentration as an indicator of the severity of cardiomyopathies.

Animals

This study included 78 control cats and 83 cats with various types of cardiomyopathy.

Methods

This was a prospective multicentre study. Control cats were determined to have a normal heart, and diseased cats were diagnosed by echocardiography. Diseased cats were divided into asymptomatic cats without left atrial dilation (LAD), asymptomatic cats with LAD, and cats with heart failure. Plasma C-terminal ANP concentrations were measured using chemiluminescence.

Results

The median plasma ANP concentration in controls was 43.3 (interquartile range, 33.0–56.3) pg/mL. Plasma ANP values were significantly higher in the cardiomyopathic cats with LAD and heart failure, but the values in cats without LAD were comparable to those in control cats. To distinguish cats with cardiomyopathy from controls, a plasma ANP concentration >77.5 pg/mL afforded sensitivity of 66.3% and specificity of 84.6%. Use of plasma ANP concentration >110.9 pg/mL to identify cats with LAD had a sensitivity of 73.6% and specificity of 93.5%. The areas under the receiver-operating characteristic curve were 0.80 and 0.86.

Conclusions

Plasma ANP concentrations were higher in cats with more advanced cardiomyopathy. Although assaying the ANP concentration alone may not help to diagnose cardiac disease, measuring provides additional information that is useful for assessing the severity of cardiomyopathies.  相似文献   
85.
ZHANG Yun  DAI Cui-lian 《园艺学报》2010,26(6):1234-1236
Degradation of most proteins in eukaryotic cells is through the ubiquition-proteasome system (UPS). Recently, it demonstrated that UPS regulates cell apoptosis and cardiac hypertrophy. The differences of UPS regulation lie in E3 ligases, which specifically recognize targets and direct the ubiquitination process. Recent evidence suggests that atrogin-1/muscle atrophy F-box (Mafbx) and muscle RING finger 1 (MuRF1) may be critical mediators of the heart and muscle atrophy and hypertrophy. This review summarizes the possible relationship between UPS and cardiac dysfunction after myocardial infarction in order to inhibit cardiac dysfunction after myocardial infarction.  相似文献   
86.
Mares give birth under high parasympathetic tone as indicated by increased heart rate variability (HRV) and atrioventricular blocks. These changes might be induced by oxytocin released at foaling. In this short communication, the cardiac (n = 4) and cortisol response (n = 3) of mares treated with oxytocin infusions because of fetal membrane retention are reported. A marked cortisol release occurred during oxytocin infusion in two mares but not in a third mare which was infused for 6 minutes only. Oxytocin-induced cortisol release was neither accompanied by an increase in heart rate nor a decrease in HRV, and heart rate even decreased during oxytocin infusions. Preliminary data indicate that cortisol release in oxytocin-treated mares is not a stress response. Treatment of retained membranes in mares with oxytocin does not induce cardiovascular side effects.  相似文献   
87.
The occurrence of heart splitting during the crosscutting of logs was discussed in relation to the released strain on Eucalyptus spp. logs. The strains released in the longitudinal and tangential directions were measured by the strain-gauge method and were correlated with the length of the heart split measured on the same logs. There were differences in the longitudinal strain; however, no significant correlation was found with the diameter that could be converted to a mean annual increment (i.e., a relation with the growth rate). The initial splits expand with the time after felling. The longer the initial split, the longer is the length 1 week after felling. The split length was significantly smaller at the butt end of the first log of every tree than at the other end, but there were no significant differences between the split length at the top of the first logs and at either end of the second logs, although there were differences among individual trees. The length of the heart split correlated with the released strain near the pith, which was estimated using Kublers equation. The longitudinal released strain measured on the surface of logs is a good indicator of the heart splitting when crosscutting logs.Part of this paper was presented at the 52nd Annual Meeting of the Japan Wood Research Society  相似文献   
88.
The effect of 3rd-degree atrioventricular block on long-term outcome in cats is unknown. Clinical findings and long-term outcome of 21 cats with 3rd-degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7-19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd-degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1-2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd-degree atrioventricular block survived > 1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third-degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive > 1 year without pacemaker implantation.  相似文献   
89.
The purpose of this study was to investigate the prognostic value of various clinical, ECG, echocardiographic, and Doppler echocardiographic variables in dogs with dilated cardiomyopathy. The relationship to survival of 11 variables was evaluated in 63 dogs. Studied variables were age at time of diagnosis, class of heart failure (HF), dyspnea, ascites, atrial fibrillation (AF), ejection fraction (EF), E-point septal separation, end-diastolic volume index, end-systolic volume index (ESV-I), and restrictive or nonrestrictive transmitral flow (TMF) pattern. Median survival time was 671 days (lower 95% confidence limit, 350 days). Survival curves showed that severity of HF, ascites, ESV-I greater than 140 mL/m2, EF less than 25%, and restrictive TMF pattern had a significant negative relation to survival time. Thirty-nine dogs with both sinus rhythm and AF presented adequate TMF recordings; in these dogs, after stratification by TMF pattern, the restrictive TMF pattern was the most important negative prognostic indicator. We conclude that in dogs with dilated cardiomyopathy the restrictive TMF pattern appears to represent a useful prognostic indicator. Class of HF, ascites, ESV-I, and EF are also useful indexes if an adequate TMF pattern is not recorded.  相似文献   
90.
The heart rate and the pulmonary artery wedge pressure (PWP) was measured in 10 healthy warmblood horses and in six warmblood horses with atrial fibrillation (AF) at rest and during standardised treadmill exercise. During treadmill exercise, the increase in heart rate was significantly higher in the horses with AF than in the healthy horses. Horses with AF showed a significantly higher increase in PWP at treadmill velocities of 5m/s and faster, than did the healthy horses. The differences in PWP between both groups increased with treadmill strain. The present study demonstrates that there is an influence on the haemodynamics in horses with AF during treadmill exercise, which could explain exercise intolerance in some horses with lone AF.  相似文献   
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