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811.
 We investigated small- and large-bowel specimens of three newborn infants presenting with the clinical and radiological symptoms of megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS). Conventional histological staining revealed marked thinning of the longitudinal muscle layer. Electron-microscopic investigations showed typical “central core” vacuolic degeneration of smooth-muscle-cells combined with proliferation of col lagen fibres. The expression of α-smooth-muscle actin was absent or markedly reduced in the circular and longitudinal muscle layers and muscularis mucosae compared to the normal controls. These findings suggest that the intestinal obstruction in MMIHS is due to an abnormality of the smooth-muscle cells.  相似文献   
812.

Background

Obesity in pregnancy is a global health problem which is associated with poor pregnancy outcomes. The use of weight and height, measured at about ten weeks of gestation, to produce pre-gestational body mass index is recommended for the diagnoses of the condition but limitations abound in under resourced settings.

Objectives

To measure anthropometric indices such as mid upper arm circumference, calf circumference, waist circumference and waist to hip ratio, for identification of obesity in pregnancy.

Methods

Anthropometric measurements were carried out on cohorts of pregnant women from 4 hospitals in Enugu, South-eastern Nigeria.

Results

There were no significant difference in the mean mid upper arm circumference (MUAC) and calf circumference (CC) across the trimester groups. The mean values of waist circumferences, hip circumference and waist to hip ratios changed significantly across the trimesters. The 75th percentile of MUAC (33 cm) and CC (39 cm) in all trimesters, had sensitivity and specificity of more than 70% for identifying obesity in pregnancy.

Conclusion

MUAC and CC values of 33cm and 39cm respectively might be reliable cut off points for diagnoses of obesity throughout pregnancy in Enugu, Nigeria  相似文献   
813.
Absence of DAZ gene mutations in cases of non-obstructed azoospermia   总被引:5,自引:0,他引:5  
Sequenced-tagged site (STS) analysis of the Y chromosome long arm (Yq) of azoospermic males has identified a minimum common deleted region of several hundred kilobases in approximately 13% of cases. A candidate azoospermia gene, DAZ (deleted in azoospermia), has been isolated from this region. DAZ has also been shown to be absent in severely oligozoospermic males albeit at a much lower frequency. These data, although highly suggestive, do not constitute formal proof that DAZ actually plays a role in azoospermia, as no small intragenic deletions, rearrangements or point mutations in the gene have been found. In this study we report the screening of DNA from 168 azoospermic/oligospermic males for the presence of the DAZ gene. Deletions involving DAZ were detected in five out of 43 (11.6%) azoospermic males whereas none were found in the remaining 125 oligospermic patients. We present the genomic structure of the 5' end of the DAZ gene together with its sequence analysis in 30 non-obstructed azoospermic males. No mutations in DAZ were found in any of the patients sequenced. These data provide no formal proof that DAZ is AZF. Thus the possibility is still valid that another gene(s) mapping to the deletion interval may be responsible for, or contribute to, the observed phenotypes. Alternatively, if DAZ is AZF, they suggest that the most frequent cause of gene inactivation is via large deletions possibly mobilized by Y chromosome repetitive sequences.   相似文献   
814.
At present, there are various biomaterials that have high biocompatibility. In particular, there are many types of coated circuits in cardiopulmonary bypass (CPB) systems. However, only a few clinical studies have investigated platelet aggregation caused by these coated circuits. In this study, a CPB system coated with poly-2-methoxyethylacrylate (X coating) was used to ascertain whether platelet aggregation could be suppressed during CPB, and a comparison was made between X coating and ordinary (covalently bonded) heparin coating. The subjects were 19 adult patients who were scheduled to undergo valve replacement or valvuloplasty. They were divided into two groups: group X (X coating) and group H (heparin coating). The platelet aggregation threshold index (PATI, grading curve) and β-thromboglobulin and plalelet factor IV levels were assessed preoperatively (control), 5 min after heparin administration, 10 and 60 min after the start of CPB, and 0 and 2 h after the end of CPB. The results indicated that platelet aggregation was reduced during CPB and that platelets were activated. The changes in platelet aggregation associated with the X coating were shown to be similar to those associated with heparin coating.  相似文献   
815.
IL-7 and IL-15 are important cytokines for CD8 memory T cells. However, the extent that IL-7 is essential for CD8 T cell memory remains unclear because blocking IL-7 in vivo results in near complete inhibition of T cell development with the few mature T cells exhibiting functional abnormalities. To bypass this complication, CD8 memory development was examined utilizing a mouse model where transgenic IL-7Ralpha was selectively expressed in the thymus of IL-7Ralpha(-/-) mice. T cell development was corrected but the resulting peripheral T cells were essentially IL-7 non-responsive. Activation of IL-7R-defective OT-I CD8(+) T cells with OVA(257-264) and IL-2 readily yielded CTL. Upon further culture with IL-15, these CTL expressed phenotypic and functional properties of central memory-like cells. Thus, IL-7R-defective CD8(+) T cells do not exhibit intrinsic defects in effector or memory development. When IL-7R-defective OT-I CTL were adoptively transferred into normal or IL-15(-/-) recipient mice in a non-inflammatory setting, they converted into memory-like cells, but did not persist, which was even more striking in IL-15(-/-) recipients. This poor persistence was rescued after expression of transgenic Bcl-2 in IL-7R-defective OT-I T cells. Collectively, these data indicate that IL-7 is non-redundantly required for the survival of CD8 memory T cells.  相似文献   
816.
Spinal deformities and surgical correction of scoliosis can make intrathecal delivery of nusinersen very challenging. We aim to evaluate the feasibility and safety of intrathecal administration of nusinersen either via interlaminar or transforaminal approach in a cohort of adult and adolescent patients with spinal muscular atrophy (SMA). Twelve patients were treated with nusinersen in our center under CT-guidance; after a CT scan of the lumbar column, we identified a safe virtual trajectory for the needle and defined patients to address to the transforaminal approach (seven patients) or the interlaminar approach (five patients). Out of 47 procedures, all injections but one were successful. There was one adverse event (post-lumbar puncture syndrome) in the interlaminar approach group (out of 20 procedures) and four adverse events in TFA group (out of 27 procedures) including one serious adverse event, a subarachnoid hemorrhage that required hospitalization. Transforaminal approach can be considered an effective option for nusinersen administration but potentially associated with serious complications, therefore it should be recommended in very selected patients.  相似文献   
817.
Invagination     
Intussusception is the most frequent cause of ileus in infants and toddlers. It is characterized by the prolapse of a more proximal bowel segment into the lumen of a more distal segment, resulting in venous stasis and bowel wall edema. Without treatment this leads to arterial occlusion with bowel necrosis and perforation. In total, 90% of intussusceptions are ileocolic. Following infancy, the likelihood of a pathologic lead point (Meckel’s Diverticulum, polyp, lymphoma) being the cause of intussusception increases. Clinically there is the classic triad of abdominal pain, vomiting and “redcurrant jelly stool”. Intussusception is frequently preceded by viral gastroenteritis. The diagnosis is made using ultrasound and the intussusception is treated by ultrasound-guided hydrostatic reduction. Rapid initiation of conservative therapy has a positive impact on the success rate of reduction. In the case of perforation or peritonitis, immediate laparotomy is indicated.  相似文献   
818.
The present study examined to what extent patients with Broca's aphasia and healthy controls rely upon prearticulatory and postarticulatory monitoring processes for detecting and repairing errors in speech production. Monitoring skills were investigated in a speaking situation with normal auditory feedback, a speaking situation with white noise, and a situation in which errors had to be detected in other-produced speech. The results demonstrated that the Broca's aphasics repaired a lower percentage of errors than the controls in the situation with normal auditory feedback, whereas their performance in the noise-masked condition was comparable. In contrast to the controls, the aphasics did not suffer from the presence of white noise. In addition, the proportion of covert repairs was higher for the Broca's aphasics than for the healthy controls. These findings indicate that Broca's aphasics concentrate primarily on prearticulatory monitoring. Possible explanations for this strong reliance on prearticulatory monitoring processes are discussed.  相似文献   
819.
Background  Postnatal depression (PND) is a common mental health problem, which is associated with adverse consequences beyond the individual with depression. It is not known whether using formal methods to identify PND are clinically and cost effective in improving maternal and infant outcomes.
Objectives  To evaluate the clinical and cost effectiveness of antenatal and postnatal identification of depressive symptoms.
Search strategy  Twenty electronic databases were searched to retrieve English and non-English language articles published until February 2007.
Selection criteria  Randomised controlled trials or controlled trials comparing the use of formal methods to identify PND, with or without enhancement of care, or feedback of scores with not using formal methods to identify PND or usual care.
Data collection and analysis  Two reviewers independently assessed studies for inclusion and extracted data. Results from the trials were combined to calculate odds ratios and 95% confidence intervals for dichotomous outcomes.
Main results  Five studies were identified that compared formal use of a method to identify PND, with or without enhancement of care, or feedback of scores with not using a formal method or usual care. All of the studies used the Edinburgh Postnatal Depression Scale (EPDS) to identify women with PND. The results of the studies indicated beneficial effects of using the EPDS in reducing EPDS scores (OR = 0.61; 95% CI 0.48–0.76).
Author's conclusions  Despite some apparent beneficial effects of using formal methods to identify PND, it is difficult to disentangle the effects of the screening component alone from interventions linked to a positive screen as some of the studies included enhancements of care and/or an intervention.  相似文献   
820.
Mismatch between bone marrow transplant (BMT) patient and donor for an amino acid polymorphism within the adhesion molecule CD31 has recently been reported to increase risk for the development of graft-versus-host disease (GVHD). We further examined this association in a larger series of 301 BMT patients (227 with grade III/IV GVHD and 74 with grade 0 GVHD) and their HLA-identical sibling donors. CD31 genotypes were determined by polymerase chain reaction and restriction endonuclease digestion. The role of mismatch at the CD31 locus in the development of GVHD was assessed by analyzing the extent of CD31 identity and CD31 compatibility among the grade 0 GVHD and grade III/IV GVHD sibling pairs. No significant association between CD31 mismatch and the development of severe GVHD was detected in our overall patient population. Sixty-three percent of grade III/IV GVHD sibling pairs and 69% of grade 0 GVHD sibling pairs had CD31 genotypes that were identical (P = .36, odds ratio = 1.30). In addition, neither the grade 0 GVHD group (P = .10) nor the grade III/IV GVHD group (P = .27) differed significantly from the expected probability of identity between sibling pairs. Mismatch at the CD31 polymorphism between recipients and donors showed no consistent association with the development of GVHD. Current evidence does not support the value of CD31 mismatch in the selection of BMT donors.  相似文献   
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