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41.
Purpose:Incisions in cataract surgery can be modified in various ways in terms of size, shape, and axis to reduce or tailor astigmatism. This study was conducted to examine the effect of site (superior vs, temporal) and shape (frown vs. V-shaped, chevron) of scleral incisions for cataract surgery on corneal curvature.Methods:The prospective study was carried out on 200 consecutive patients with senile cataract and who were planned for surgery at a tertiary eye hospital in north India. The placement of the incision was decided by the steeper corneal meridian—whether superior or temporal—and then patients of these two groups were randomized for frown and V-shaped incision; in this way, four groups of 50 patients each were formed. Follow-up was done on day 1, at 2 weeks, 4 weeks, 8 weeks, and 12 weeks. At each follow-up, post-operative keratometry with routine postoperative examination was done. The results were statistically analyzed by using student’s t-test, Chi-squared test, and the Pearson correlation coefficient.Results:In all the four groups, the difference of preoperative astigmatism and surgically-induced astigmatism was statistically highly significant. The analysis of uncorrected visual acuity (UCVA) was statistically significant (P < 0.05) on postoperative day 1 and at 2, 4, and 12 postoperative weeks; it was statistically insignificant (P > 0.05) at postoperative week 8.Conclusion:Temporal incisions result in lesser postoperative surgically induced astigmatism (SIA) than superior incisions. Chevron incisions result in minimal change in corneal curvature. This effect can be utilized to tailor the postoperative astigmatism.  相似文献   
42.
Burden and risk factors for wasting in the first 6 months of life among Indian children are not well documented. We used data from India's National Family Health Survey 4 to estimate the prevalence of severe wasting (weight for length < ‐3 SD) among 18,898 infants under 6 months of age. We also examined the association of severe wasting with household, maternal, and child‐related factors using multivariable logistic regression analysis. Prevalence of severe wasting among infants less than 6 months of age was 14.8%, ranging from 3.5 to 21% across states. Low birth weight (<2,500 g; adjusted odds ratio [AOR] 1.40, 95% CI [1.19, 1.65]), nonutilization of supplementary nutrition by mother during lactation (AOR 1.23, 95% CI [1.05, 1.43]), and anthropometric assessment during summer (AOR 1.37, 95% CI [1.13, 1.65]) and monsoon months (AOR 1.53, 95% CI [1.20, 1.95]) were associated with higher odds of severe wasting. Infants aged 2 to 3 months (AOR 0.78, 95% CI [0.66, 0.93]) and 4 to 5 months (AOR 0.65, 95% CI [0.55, 0.73]) had lower odds of severe wasting as compared with the 0‐ to 1‐month category. This analysis reveals a high burden of severe wasting in infants less than 6 months in India. Preventive interventions must be targeted at reducing low birth weight due to fatal growth restriction and prematurity. Appropriate care practices at facilities and postdischarge with extra attention to those born small and sick can prevent further deterioration in nutritional status.  相似文献   
43.
44.
In last decade, dengue has emerged as one of the most important vector born disease. With increasing cases, uncommon presentations and complications are now commonly recognized. Here, we report two cases of rare pattern of respiratory involvement in dengue: acute respiratory distress syndrome and bronchiolitis with respiratory failure.  相似文献   
45.
46.
Bhan MK  Bahl R  Bhatnagar S 《Lancet》2005,366(9487):749-762
Typhoid fever is estimated to have caused 21.6 million illnesses and 216,500 deaths globally in 2000, affecting all ages. There is also one case of paratyphoid fever for every four of typhoid. The global emergence of multidrug-resistant strains and of strains with reduced susceptibility to fluoroquinolones is of great concern. We discuss the occurrence of poor clinical response to fluoroquinolones despite disc sensitivity. Developments are being made in our understanding of the molecular pathogenesis, and genomic and proteomic studies reveal the possibility of new targets for diagnosis and treatment. Further, we review guidelines for use of diagnostic tests and for selection of antimicrobials in varying clinical situations. The importance of safe water, sanitation, and immunisation in the presence of increasing antibiotic resistance is paramount. Routine immunisation of school-age children with Vi or Ty21a vaccine is recommended for countries endemic for typhoid. Vi vaccine should be used for 2-5 year-old children in highly endemic settings.  相似文献   
47.
We reviewed our 3-year experience in treating interruption of the aorta in adult patients. Clinical profiles, surgical management, and results of early and mid-term follow-up are presented. From August 2001 through June 2003, 7 adult patients underwent an extra-anatomic bypass procedure to repair interruption of the aortic arch. Five patients underwent ventral aortic repair through a mid-sternotomy and an upper midline laparotomy, and 2 patients underwent repair through a left posterolateral thoracotomy. A bovine collagen-impregnated polyester fiber graft was used in 6 patients, and a Gore-Tex graft was interposed in 1 patient. All repairs were performed without cardiopulmonary bypass. Follow-up was complete in all patients. The mean follow-up was 1728 +/- 1 months (range, 9-31 months). No neurologic, renal, or gastrointestinal complications were noted in any patient. There was no in-hospital or late mortality or need for re-intervention. All patients were asymptomatic; however, 5 patients had mild residual hypertension. Graft patency in all the patients was confirmed by computed tomographic angiography. Interruption of the aorta is rare in adults. Ventral aortic repair through a midline approach is our preferred technique for surgical repair of this entity, because it avoids the extensive network of collateral vessels on the chest wall, enables simultaneous treatment of associated lesions, and in all likelihood reduces morbidity and mortality.  相似文献   
48.
Total anomalous pulmonary venous connection: surgical experience in Indians   总被引:4,自引:0,他引:4  
BACKGROUND: We report a retrospective analysis of the demographic. morphological and clinical profiles of patients along with results of operative repair for total anomalous pulmonary venous connection. METHODS AND RESULTS: In the last 15 years, 248 patients (168 boys, 80 girls) underwent repair for total anomalous pulmonary venous connection. Their ages ranged from I day to 24 years (median 8 months) and 145 of them were < or = 1 year of age. The patients' weight ranged from 2 to 52 kg (median 5 kg). About 70% of patients (n = 174) were less than the 50th percentile of predicted weight for age and sex. The anomalous connection was supracardiac in 134 (54%), cardiac in 80 (32.2%), infracardiac in 9 (3.6%) and mixed in 25 (10.1%) patients. Fifty (20.2%) patients had obstructed drainage and 76 patients (30.2%) had moderate or severe pulmonary arterial hypertension. Forty-five patients (18.1%) had to be operated upon on an emergency basis. All the patients were operated upon using moderately hypothermic cardiopulmonary bypass. In 114 patients, circulatory arrest was used. There were 45 (19.1%) in-hospital deaths. The major causes of early death were pulmonary arterial hypertensive crisis in 19 (7.7%) and low cardiac output syndrome in 17 (6.9%) patients. Age < or = 1 year (odds ratio 2.16; 95% confidence interval: 1.22-3.82, p=0.008), severe pulmonary arterial hypertension (odds ratio 5.86; 95% confidence interval: 2-17, p=0.001), and need for emergency surgery (odds ratio 3.65; 95% confidence interval: 1.59-8.38, p=0.002) were independent risk factors for early death. Follow-up ranged from 1 to 180 months (median 48 months). There were 4 lake deaths. Actuarial survival at 12 years was 92.6% +/- 2.8%. CONCLUSIONS: In Indian circumstances, mortality continues to be high in infants with total anomalous pulmonary venous connection. Severe pulmonary arterial hypertension appears to be the most important predictor of operative mortality. Severe malnutrition, delayed diagnosis and late referrals possibly contribute to the high mortality.  相似文献   
49.
Lee  SB; Rao  AK; Lee  KH; Yang  X; Bae  YS; Rhee  SG 《Blood》1996,88(5):1684-1691
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.  相似文献   
50.
Yang  X; Sun  L; Ghosh  S; Rao  AK 《Blood》1996,88(5):1676-1683
Signal transduction on platelet activation involves phosphoinositide- specific phospholipase C (PLC)-mediated hydrolysis of phosphatidylinositides and formation of inositol-1,4,5-triphosphate [I(1,4,5)P3], which mediates Ca2+ mobilization, and diacylglycerol (DG), which activates protein kinase C (PKC) to phosphorylate a 47-kD protein (Pleckstrin). We studied these events in two related patients previously reported (Blood 74:664, 1989) to have abnormal aggregation and 14C-serotonin secretion, and impaired intracellular Ca2+ mobilization in response to several agonists. Thrombin-induced I(1,4,5)P3 and phosphatidic acid formation were diminished. Pleckstrin phosphorylation was impaired on activation with thrombin, platelet- activating factor, and ionophore A23187, but was normal with PKC activator 1,2-dioctonyl-sn-glycerol (DiC8). Ca2+ mobilization induced by guanosine triphosphate (GTP) analog guanosine 5'-0-(3 thiotriphosphate) (GTP gamma S) was diminished. Pretreatment with either A23187 or DiC8 did not correct the impaired adenine diphosphate- induced secretion; however, upon stimulation with A23187 plus DiC8, pleckstrin phosphorylation and secretion were normal, indicating that both PKC activation and Ca2+ mobilization are essential for normal secretion. We conclude that these patients have a unique inherited platelet defect in formation of two key intracellular mediators [I(1,4,5)P3 and DG] and in the responses mediated by them due to a defect in postreceptor mechanisms of PLC activation.  相似文献   
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