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81.
We report herein a case of a 58‐year‐old woman with COVID‐19. During the hospitalization, the patient complained of acute abdominal pain, and abdominal CT revealed the rectus sheath hematoma (RSH). Since corticosteroids and anti‐coagulation are commonly administered in COVID‐19 patients, physicians should consider RSH as a possible diagnosis for acute abdominal pain.  相似文献   
82.
The ability to extract different bio-medical parameters from one single wristwatch device can be very applicable. The wearable device that is presented in this paper is based on two optical approaches. The first is the extraction and separation of remote vibration sources and the second is the rotation of linearly polarized light by certain materials exposed to magnetic fields. The technique is based on tracking of temporal changes of reflected secondary speckles produced in the wrist when being illuminated by a laser beam. Change in skin’s temporal vibration profile together with change in the magnetic medium that is generated by time varied glucose concentration caused these temporal changes. In this paper we present experimental tests which are the first step towards an in vivo noncontact device for detection of glucose concentration in blood. The paper also shows very preliminary results for qualitative capability for indication of dehydration.OCIS codes: (030.6140) Speckle, (280.0280) Remote sensing and sensors, (170.0170) Medical optics and biotechnology, (260.2110) Electromagnetic optics, (260.5430) Polarization  相似文献   
83.
The focal point of this work is the design and comparison of two types of iron doped TiO2 prepared by a simple sol–gel method and then encapsulated in an alginate matrix. The as-prepared recyclable bio-nanocomposite photocatalysts were made of different amounts of TiO2-Fe2O3 and TiO2-Fe3O4 (1%, 2.5%, 5%, and 10%) and were developed to improve the photocatalytic efficiency of TiO2 and simultaneously to achieve an expanded visible-light response range with high visible-light absorption potential in order to degrade organic pollutants from aqueous solutions, as a potential application. As it is essential to characterize a material to better understand it, accurate characterization of the resulting bio-nanocomposites was carried out using X-ray diffraction (XRD), scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectroscopy (FTIR) and UV-diffuse reflectance spectroscopy (UV-DRS). In this study, the emphasis on blending the alginate and the iron doped-TiO2 photocatalyst nanoparticles results in a multicomponent particular shaped system that exhibits a porous structure, an exceptional surface area and a smaller band gap due to the presence of iron nanoparticles that could also maintain e/hole separation for better photocatalytic activity under visible light.

Iron oxide/titania oxide are encapsulated in alginate biopolymer. These bio-nanocomposites are suitable for the photodegradation of dissimilar organic pollutants under UV irradiation as well as visible light.  相似文献   
84.
The purpose of this study was to evaluate the efficacy of Ca(OH)2 with or without a silver nanoparticle suspension to eliminate Enterococcus faecalis from root canals. A total of 66 extracted human single‐rooted teeth contaminated with E. faecalis were treated with 10% Ca(OH)2 alone, Ca(OH)2 with nanosilver or sterile water (as a negative control). Samples were obtained with paper points and Gates‐Glidden burs at 1 and 7 days after root canal preparation and the number of colony‐forming units (CFU) was determined. The number of CFUs observed after dressing with Ca(OH)2 + nanosilver was significantly less than the number observed with Ca(OH)2 alone after 1 or 7 days (P < 0.001, P < 0.001). No differences in antimicrobial properties were observed between the two time points in the Ca(OH)2 + nanosilver group (P > 0.05). Higher antimicrobial efficacy was observed in the Ca(OH)2 group after 7 days than 1 day (P < 0.001). This study highlighted the potential advantage of using a mixture of Ca(OH)2 and nanosilver for intracanal medicament.  相似文献   
85.
Laparoscopic cholecystectomy is a surgical procedure of choice for benign gallbladder diseases. In about 1-2% of cases histopathological examination demonstrate incidental gallbladder cancer (GBCA). We report a case of a 61 year old woman who developed port site metastases after laparoscopic cholecystectomy for adenocarcinoma of the gallbladder. Metastases appeared on all four port sites. Review of literature regarding incidental GBCA an port site metastases was also performed. We conclude that the retrieval bag should be routinely used in laparoscopic cholecystectomy; the procedure should be performed with minimal trauma; in cases of incidental GB carcinoma, full thickness excision of the abdominal wall of the port sites demands additional studies; additional liver bed excision and local lymphadenectomy for T1b carcinoma are yet to be considered.  相似文献   
86.
The association between suicidality and HIV/AIDS has been demonstrated for three decades, but little is know about risk factors that can help understand this association and help identify who is most at risk. Few research studies have been conducted in sub-Saharan Africa, a region that accounts for more than 70% of the HIV global burden. This paper describes clinical risk factors for suicidality among individuals with HIV infection and AIDS disease in Mbarara, Uganda. In this study, suicidality includes both suicidal ideation and suicidal attempts. A cross-sectional survey was conducted with 543 HIV-positive individuals aged 15 years and above, recruited from 2 HIV specialised clinics in Mbarara. Using logistic regression analysis, factors significantly associated with suicidality at 95% confidence interval were identified. The rate of suicidality was 10% (n = 54; 95% CI: 5.00–15.00). Risk factors for suicidality were: perception of poor physical health (OR 2.22, 95% CI 1.23–3.99, p = 0.007), physical pain (OR 1.83, 95% CI 1.01–3.30, p = 0.049), reducing work due to illness (OR = 2.22, 95% CI 1.23–3.99, p = 0.004) and recent HIV diagnosis (OR 1.02, 95% CI 1.01–1.03, p = 0.001). These findings suggest that HIV/AIDS in south-western Uganda is associated with a considerable burden of suicidality. HIV is associated with several clinical factors that increase vulnerability to suicidality. There is need for more appropriate interventions targeting these clinical risk factors, systematic suicide risk assessment and management of suicidal ideation and behaviours in HIV care.  相似文献   
87.
It is recognized that FMR1 premutation expansions are associated with premature ovarian failure (POF), but their role in diminished ovarian reserve (DOR) is not clearly established. Moreover, the impact of smaller repeats at the boundary of premutation and normal is less clear. Therefore, we have compared the frequency of these intermediate (45–54 repeats) and premutation (>55) sized FMR1 CGG repeats among a patients group including 188 DOR and 173 POF women and 200 controls. FSH and LH concentrations were also compared between intermediate and premutation ranges in patients. The 5′ UTR of FMR1 gene was amplified using PCR. The numbers of trinucleotide repeats were confirmed by the Sanger sequencing method. The frequency of premutation was higher in POF and DOR patients in comparison with controls, but the difference in the incidence of intermediate alleles was not statistically significant among these groups. The mean level of serum FSH was higher in patients with premutation than patients with intermediate alleles. Based on the current evidence, we concluded that intermediate-sized FMR1 CGG repeat alleles should not be considered as a high-risk factor for POF and DOR.  相似文献   
88.

Purpose

The aim of this study was to investigate whether treatment of sperm from infertile patients would gluthatione could reduce sperm premature chromosome condensation (PCC). To reach the goals of this study, the frequency of sperm PCC formation in sperm of normal and sub-fertile men with/without glutathione treatment were compared and analyzed.

Methods

Hamster oocytes were retrieved after super ovulation by PMSG and HCG injection. Following treatment with hyaluronidase, zonae was removed by trypsin digestion. Sperm were classified into 3 groups according to morphology, movement and counts, treated with glutathione(10 μg/ml) and then processed by swim up method. After capacitation, zona-free oocytes were incubated with sperm then transferred to fresh media containing colcemid. Cells were fixed and slides prepared using Tarkowskie’s standard air drying technique and after staining in 5% Giemsa, oocytes were analyzed at high magnification.

Results

Sperm penetration rate was higher and the rate of intact sperm head and PCC was lower in GSH treated samples compared to non treated groups. Sperm penetration rate was significantly higher in treated astheno sperm samples compared to non-treated ones (66.4% and 50. 97% respectively) (P < 0.001). We observed a significantly higher PCC frequency in infertile patients (P < 0.001). In addition, there was a significantly lower rate of intact sperm head in treated astheno sperm samples (17.49%) compared to non treated ones (26.79%) (P < 0.001). Finally, a significantly lower rate of PCC in treated astheno sperm samples comparing to non treated ones was seen (51.06% and 72.96% respectively) (P < 0. 001).

Conclusions

Our results show that sperm PCC formation could be one of the major causes of failed fertilization in individuals with sperm abnormalities. Also sperm PCC formation may be involved in the etiology of some cases of idiopathic infertility. Given that the susceptibility of sperm to oxidative stress is significantly greater in idiopathic infertile men, our results show that treatment with glutathione could significantly reduce these stress factors and increase ART outcome.  相似文献   
89.
Background The role of nutritional factors including trace elements has been reported in the pathogenesis of many autoimmune diseases. Objective Regarding the relatively high prevalence of pemphigus vulgaris in Iran, we investigated the serum levels of zinc and copper as two important trace elements, together with the oxidative stress status in patients with pemphigus vulgaris. Materials and methods This case‐control study was performed on 25 patients with newly diagnosed pemphigus vulgaris and 25 age‐ and sex‐matched healthy control subjects. Serum concentrations of zinc, copper, ceruloplasmin as well as copper/zinc ratio were determined for each subject. Oxidative stress was also measured using a novel assay of peroxidant‐antioxidant balance (PAB). Results Mean serum concentrations of zinc and copper as well as copper/zinc ratio were significantly lower in patients (mean age: 47.2 ± 16.2 years; male/female: 14/11) compared with the controls (mean age: 47.3 ± 12.8 years; male/female: 14/11; P < 0.001). In contrast, PAB values were significantly elevated in patients compared with controls (P < 0.01). No significant difference in serum ceruloplasmin concentrations was observed between the groups (P > 0.05). Conclusion Our findings indicate that low serum zinc and copper and increased oxidative stress may be associated with pemphigus vulgaris.  相似文献   
90.
We report the diagnosis and successful clinical management of three patients with anatomical variation in the maxillary first premolars. Maxillary first premolars have highly variable root canal morphology, but the presence of three canals is rare. This article describes the diagnosis and clinical management of first maxillary premolars with three canals and three separate roots, with special reference to radiographic interpretation and access refinements.  相似文献   
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