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61.
The increasing prevalence of penicillin-resistant Streptococuus pneumoniae urges for fast and accurate susceptibility testing methods. This study evaluated the comparability of three commonly used techniques; disk diffusion, E-test and agar dilution, to detect penicillin susceptibility in clinical isolates of S. pneumoniae. Fifty pneumococcal isolates, obtained from patients at the University of Malaya Medical Centre, were selected to include both penicillin-susceptible strains and those that had decreased susceptibility (resistant and intermediate) to penicillin. The minimum inhibitory concentration (MIC) values of penicillin to serve as the reference was determined by the agar dilution method in which, based on the MIC breakpoints recommended by the National Committee for Clinical Laboratory Standards (NCCLS), 27 strains had decreased susceptibility to penicillin with 17 strains resistant and 10 intermediate. Comparing to the agar dilution method, oxacillin disk diffusion test detected all strains with decreased penicillin susceptibility as such while E-test showed a close agreement of susceptibility (92%) of the isolates to penicillin. This confirmed that oxacillin is a good screening test for S. pneumoniae isolates with decreased susceptibility to penicillin while E-test is very reliable for rapid and accurate detection of penicillin susceptibility.  相似文献   
62.
BACKGROUND AND AIMS: Little is known about the familial characteristics of children with severe receptive specific language impairment (SLI). Affected children are more likely to have long-term problems than those with expressive SLI but to date they have only been described as small cohorts within SLI populations. We therefore aimed to describe the clinical and familial characteristics of severe receptive SLI as defined by a rigorous phenotype and to establish whether non-word repetition showed a relationship with language impairment in these families. METHODS: Cross-sectional study of children who met ICD-10 (F80.2) criteria for receptive SLI at school entry, their siblings and genetic parents with standardised measures of language and non-verbal IQ, phonological auditory memory and speech sound inventory. RESULTS: At a mean of 6 years after school entry with a severe receptive SLI, the 58 participants had a normal mean and standard deviation non-verbal IQ, but only 3% (two) had attained language measures in the normal range. One third still had severe receptive language impairment. One third of siblings not known to be affected had language levels outside the normal range. Phonological auditory memory was impaired in most family members. CONCLUSION: Severe receptive SLI is nearly always associated with an equally severe reduction in expressive language skills. Language impairment in siblings may go undetected and yet they are at high risk. Family members had weak phonological auditory memory skills, suggesting that this could be a marker for language acquisition difficulties. Receptive SLI rarely resolves and trials of therapy are urgently needed.  相似文献   
63.

Background  

Posterior urethral valve (PUV) is a significant cause of morbidity, mortality and ongoing renal damage in children. It accounts for end-stage renal disease in a proportion of children. This article aims at highlighting the current trend in the management of boys with posterior urethral valve.  相似文献   
64.

Background

Stress as a cause of illness has been firmly established. In public health and stress research a retrospective biomarker of extended stress would be an indispensible aid. The objective of this pilot study was to investigate whether concentrations of cortisol in hair correlate with perceived stress, experiences of serious life events, and perceived health in young adults.

Methods

Hair samples were cut from the posterior vertex area of (n = 99) university students who also answered a questionnaire covering experiences of serious life events, perceived Stress Scale and perceived health during the last three months. Cortisol was measured using a competitive radioimmunoassay in methanol extracts of hair samples frozen in liquid nitrogen and mechanically pulverised.

Results

Mean cortisol levels were significantly related to serious life events (p = 0.045), weakly negatively correlated to perceived stress (p = 0.025, r = -0.061) but nor affected by sex, coloured/permed hair, intake of pharmaceuticals or self-reported health. In a multiple regression model, only the indicator of serious life events had an independent (p = 0.041) explanation of increased levels of cortisol in hair. Out of four outliers with extremely high cortisol levels two could be contacted, both reported serious psychological problems.

Conclusions

These findings suggest that measurement of cortisol in hair could serve as a retrospective biomarker of increased cortisol production reflecting exposure to major life stressors and possibly extended psychological illness with important implications for research, clinical practice and public health. Experience of serious life events seems to be more important in raising cortisol levels in hair than perceived stress.  相似文献   
65.
Uterine serous carcinoma (USC) is a rare variant of endometrial cancer that is not related to increased estrogen level; rather, it arises in a background of atrophic endometrium. Our aim was to describe clinicopathologic features of 4 cases of USC arising in endometrial polyps (EPs). The mean age of the patients at presentation was 53 years (range, 50-61 years). All patients presented with postmenopausal bleeding. In 3 patients, endometrial curretings were done before surgery, which was reported as EP with superficial foci of USC, EP with few clusters of atypical cells, and high-grade serous carcinoma, respectively. All patients underwent hysterectomy with bilateral salpingo-oophorectomy and omental sampling. The uterine cavity showed an EP in all cases ranging in size from 2 to 3.5 cm (mean, 3 cm). The hysterectomy specimens revealed USC in EP as well as the adjacent endometrium in 3 patients. The nonneoplastic endometrium was atrophic in all cases. Residual tumor was not found in the endometrium in 1 case. Omental metastatic deposits were found in all cases. Tumor deposits were also seen in the serosa of uterus, fallopian tubes, and parametrium in 1 case. Two patients died of disease 2 years after diagnosis. The remaining 2 patients are alive after a follow-up of 3 years, respectively. In conclusion, USC is a rare aggressive tumor, and to establish the diagnosis, it is important to look for the small foci of the tumor in the atrophic endometrium and on the surface of the polyps as these patients are likely to harbor additional disease in the uterus or extrauterine sites. The postmenopausal group is at high risk for developing these tumors; therefore, all the endometrial biopsies/curettings and the EPs in this age group should be thoroughly sampled.  相似文献   
66.
The aim of this study was to evaluate the morphological spectrum of chromophobe renal cell carcinoma (CRCC) and diagnostic utility of a panel of three immunohistochemical stains. All cases of CRCC reported between 2002 and 2012 in the Section of Histopathology, Aga Khan University Hospital, were retrieved. A total of 45 cases were identified. Slides were reviewed and immunohistochemical stains (CK7, CD117, and vimentin) were performed. Ages ranged from 18 to 90 years (mean, 48.5 years). Male-to-female ratio was 0.8:1. The tumor was located in the left kidney in 24 patients and the right kidney in 20 patients. The tumor size ranged from 3.5 to 22 cm (mean 10 cm). Histologically, 4 were classic, 22 were eosinophilic, 16 were mixed, and 3 were sarcomatoid type. Morphologic patterns included broad alveolar, solid, nested, tubular, tubulocystic, trabecular, papillary, and microglandular. Binucleation and perinuclear halos were seen in all cases. Nuclear grooves and pseudoinclusions were seen in 17 and 6 cases, respectively. Multinucleated cells were seen in 19 cases. Mitoses ranged from 1 to 11/10 HPFs (mean 3/10 HPFs). Hyalinized stroma was seen in 38 cases and calcification in 26 cases. Necrosis was seen in 18 cases. Palisading of smaller cells around the broad alveolar pattern was noted in 5 cases. The Furhman’s nuclear grade was I (11), II (26), III (5), and IV (3). Hale’s colloidal iron was positive in all cases. Immunohistochemical stain CK7 and CD117 were positive in 100% and 95.5% of cases respectively. Vimentin was negative in all cases, except in the sarcomatoid areas of 3 cases. In conclusion, chromophobe renal cell carcinoma has certain unique morphological features and immunohistochemical profile which help to distinguish it from conventional renal cell carcinoma and oncocytoma. We identified nuclear pseudoinclusions, microglandular pattern and palisading of smaller cells, which have not been reported earlier.  相似文献   
67.

Background

The Oklahoma Trauma Registry (OTR) collects data from all state-licensed acute care hospitals. This study investigates trends and outcomes of trauma in Oklahoma using OTR.

Methods

107,549 patients (2005–2014) with major severity and one of the following criteria were included: length of hospital stay ≥48?h, dead on arrival or death in the hospital, hospital transfer, ICU admission, or surgery on the head, chest, abdomen, or vascular system. Patient characteristics, mechanisms of injury, and outcomes of trauma were analyzed.

Results

Hospital admissions due to falls increased with an annual percent change of 4.0% (95%CI: 3.1%–4.9%) while hospital admissions due to motor vehicle crashes decreased. The number of overall deaths per year remained stable except for the fall-related deaths, which increased proportionate to the increase in the incidence of fall. Fall-related mortality was 4.2% and intracranial bleeding was present in 60% in these patients.

Conclusion

Falls are significantly increasing as a mechanism of trauma admissions and trauma-related deaths in Oklahoma. Analysis of state-based trauma registries can identify trends in etiologies of injuries and may indicate a reference point to prioritize preventive plans.  相似文献   
68.

Context

Magnesium sulphate is now the gold standard for the control of eclamptic fits. The place of low-dose magnesium sulphate for the control of eclamptic seizures is yet to be determined.

Objectives

To determine the effectiveness of low-dose magnesium sulphate in controlling eclamptic fits.

Study design

Randomized controlled trial comparing low-dose with standardized dosing regimen.

Setting

Labour Unit of the department of Obstetrics and Gynecology Federal Medical Centre Azare, north-eastern Nigeria.

Protocol

Thirty-nine patients randomized into the low-dose regimen group received 9 g loading dose (4 g iv and 5 g im) and im maintenance of 2.5 g four hourly for 24 h post-delivery or post last fit, while the 33 patients in the standard dose regimen group received loading dose of 14 g followed by im maintenance dose of 5 g four hourly. In both study groups, 2 g iv of magnesium sulphate is given for breakthrough fits and 10 ml of 10 % calcium gluconate (slowly iv) was administered in the event of toxicity. Outcome measures include recurrent fits, mode of delivery, mean Apgar Score at 5 min, perinatal death, maternal complications including death.

Result

The mean age of the 72 patients was 22.3 ± 5.4 years and 60 % were primigravidas. Intrapartum eclampsia was encountered in 44 % of the patients followed by antepartum eclampsia (26 %). Overall 4.2 % recurrent convulsion rate was documented and it is not different among the study groups. There were also no differences in both foetal and maternal outcomes in the two study groups.

Conclusion

The effectiveness of low-dose regimen of magnesium sulphate appeared comparable to the ‘standard dose regimen’. Low-dose regimen may guarantee more safety and in an environment (such as ours) where cost is an important determinant of accessibility to qualitative health services, it is certainly attractive. More studies are needed to establish the place of low-dose regimen of magnesium sulphate in the management of eclampsia.  相似文献   
69.
BackgroudDue to extensive fibrosis during revision surgery, adequate exposure is essential and it can be achieved with several extensile approach options, such as tibial tubercle osteotomy. Information regarding surgical exposure during revision arthroplasty is limited in developing countries, such as Pakistan, due to the lack of adequate data collection and follow-up. Therefore, the purpose of this study was to evaluate the impact of tibial tubercle osteotomy on final outcome of revision total knee arthroplasty (TKA).MethodsA total of 231 revision TKAs were performed between January 2008 and December 2017. Twenty-nine patients underwent tibial tubercle osteotomy for adequate exposure during revision surgery. Of these, 27 patients with complete follow-up were included in our study. Factors examined include age at the time of revision surgery, gender, comorbidities, arthroplasty site (right or left), body mass index (BMI), and primary indications for the tibial tubercle osteotomy during revision TKA. Functional outcome was measured by using Knee Society score (KSS) at 3 months and the final follow-up. All statistical analysis was done using SPSS version 20.0 with a p-value < 0.05 considered significant.ResultsOut of 27 patients, 6 patients (22.2%) were men and 21 patients (77.7%) were women. Right knee revision arthroplasty was performed in 15 patients (55.5%), left knee revision arthroplasty was performed in 12 patients (44.4%), and bilateral revision surgery was performed in only 1 patient (3.7%). The mean BMI was 29.2 kg/m2. We used a constrained condylar knee in 20 patients (74%), a rotating hinge knee in 5 patients (18.5%), and mobile bearing tray plus metaphyseal sleeves in 2 patients (7.4%). The KSS was 52.21 ± 4.05 preoperatively, and 79.42 ± 2.2 and 80.12 ± 1.33 at 3 months and 12 months, respectively. Radiological union was achieved in all patients at 3 months. Of 27 patients, only 1 patient (3.7%) had proximal migration of the osteotomy site at 6 months: the patient was asymptomatic and union was also achieved and, therefore, no surgical intervention was performed.ConclusionsTibial tubercle osteotomy during revision TKA can be a safe and reliable technique with superior outcomes and minimal complication rates.  相似文献   
70.
Vascularized bone marrow transplant (VBMT) induces donor-specific chimerism in experimental models across the major histocompatibility barrier. An experimental model for immunotolerance studies should sustain a high antigenicity with low morbidity. Accordingly, we introduced an iliac bone osteomusculocutaneous (IBOMC) transplant model in rat. It consists of a large skin component and an abundant bone marrow cells (BMC) population. We tested this model with isograft transplantations between Lewis rats (RT1l) and with allograft transplantation between Lewis-Brown Norway (LBN RT1l + n) donors and Lewis (RT1l) recipients under low dose of cyclosporine A monotherapy. Immunologic responses were tested for donor cell engraftment and chimerism induction. All isografts survived indefinitely and allografts were viable at 200 days post-transplant under low dose of cyclosporine A. Microangiography of the graft revealed preservation of skin, muscle, and bone components. Histologic examination confirmed viability of all allograft components without signs of rejection. Long-term engraftment of donor-origin (RT1n) BMC was confirmed by donor-specific chimerism (1.2%) in peripheral blood and bone marrow (1.65%) compartments and by engraftment into lymphoid organs of recipients. The IBOMC transplant proved to be a reliable composite tissue allotransplantation (CTA) model. Moreover, because of its robust bone marrow component and large skin component, it is applicable to studies on immunologic responses in CTA.  相似文献   
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