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21.

Background/Aims:

Inflammatory bowel disease (IBD) was previously thought a rare disease among children in Kuwait since most diarrhea cases were attributed to infections. In the past few years we observed an increase in the number of patients presenting with IBD. In this study we aimed to determine the epidemiology of IBD among children in the State of Kuwait.

Patients and Methods:

The charts of all children with IBD who were referred to the pediatric gastroenterology unit during the period February 1998 to January 2008 were retrospectively reviewed.

Results:

Out of a total of 130 children with IBD, 92 (71%) had Crohn''s disease, 36 (28%) had ulcerative colitis and two (1%) had indeterminate colitis. The estimated annual incidence for IBD was 2.16/105 /year. The age range was nine months-15 years (median: 11 years). Fifty-three percent of all patients were females and 77% were Kuwaiti nationals. Positive family history was found in 23%. The commonest presenting symptoms were abdominal pain (87%) and diarrhea (82%). Failure to thrive was detected in 35% and short stature in 20% at presentation. The ileocolonic region was the most common presentation site affected in Crohn''s patients and pancolitis was the commonest in ulcerative colitis.

Conclusion:

Inflammatory bowel disease is not uncommon in our children. We found no differences regarding disease presentation and clinical features compared to the Western world.  相似文献   
22.
Brain oscillations constitute a prominent feature of electroencephalography (EEG), in both physiological and pathological states. An efficient separation of oscillation from transient signals in EEG is important not only for detection of oscillations, but also for advanced signal processing such as source localization. A major difficulty lies in the fact that filtering transient phenomena can lead to spurious oscillatory activity. Therefore, in the presence of a mixture of transient and oscillatory events, it is not clear to which extent filtering methods are able to separate them efficiently. The objective of this study was to evaluate methods for separating oscillations from transients. We compared three methods: finite impulse response (FIR) filtering, wavelet analysis with stationary wavelet transform (SWT), time-frequency sparse decomposition with Matching Pursuit (MP). We evaluated the quality of reconstruction and the results of automatic detection of oscillations intermingled with transients. The emphasis of our study was on epileptic signals and single channel processing. In both simulations and on real data, FIR performed generally worse than the time-frequency methods. Both SWT and MP showed good results in separation and detection, each method having its advantages and its limitations. The SWT had good results in separation and detection of transients due to the time invariance property, but still did not completely resolve the frequency overlap for the oscillation during the time-frequency thresholding. The MP provides a sparse representation, and gave good results for simulated data. However, in the real data, we observed distortions introduced by the subtractive approach, and departure from dictionary waveforms. Future directions are proposed for overcoming these limitations.  相似文献   
23.
The present study reports on the in vitro antileishmanial activity of two Ircinidae (Dictyoceratida, Demospongiae, Porifera) Ircinia spinosula and Sarcotragus sp. Sampled from the east coast of Tunisia. The ethyl acetate, dichloromethane, and aqueous extracts were tested against Leishmania major promastigotes. The anti-proliferative activity was checked using different extracts concentration during 72 h. We found that the IC50 (sub-inhibitory concentration) values ranged from 1.39 to 264.67 μg/ml. The most active extract was that from sarcotragus sp dichloromethane extract. Microscopic observations showed that the extracts promoted cellular alterations and induce enlargement of the nucleus and modification of the parasite shape. These promising results in relation with in vitro antileishmanial activity open the way for complementary investigation in order to purify and identify active molecules.  相似文献   
24.
25.
The electrical characterization ofa La0.9Sr0.1MnO3 compound sintered at 800, 1000 and 1200 °C was investigated by means of the impedance-spectroscopy technique. As the results, the experimental conductivity spectra were explained in terms of the power law. The AC-conductivity study reveals the contributions of different conduction mechanisms. Indeed, the variation in the frequency exponents (‘s1’ and ‘s2’) as a function of the temperature confirms the thermal activation of the conduction process in the system. It proves, equally, that the transport properties are governed by the non-small-polaron-tunneling and the correlated-barrier-hopping mechanisms. Moreover, the values of the frequency exponents increase under the sintering-temperature (TS) effect. Such an evolution may be explained energetically. The jump relaxation model was used to explain the electrical conductivity in the dispersive region, as well as the frequency-exponent values by ionic conductivity. Under electrical polarization with applied DC biases of Vp = 0.1 and 2 V at room temperature, the results show the significant enhancement of the electrical conductivity. In addition, the dielectric study reveals the evident presence of dielectric relaxation. Under the sintering-temperature effect, the dielectric constant increases enormously. Indeed, the temperature dependence of the dielectric constant is well fitted by the modified Curie–Weiss law. Thus, the deduced values of the parameter (γ) confirm the relaxor character and prove the diffuse phase transition of our material. Of note is the high dielectric-permittivity magnitude, which indicates that the material is promising for microelectronic devices.  相似文献   
26.
The synthetic pyrethroids are expected to cause deleterious effects on most of the organs and especially on the male reproductive system. The current study was performed to assess the adverse effect of lambda cyhalothrin (LC) on reproductive organs and fertility in male rats and to evaluate the protective role of caffeic acid phenethyl ester (CAPE) in alleviating the detrimental effect of LC on male fertility. A total of 48 male rats were divided into 4 groups (12 rats each): control group received distilled water ad libitum and 1 ml of vehicle solution given intraperitoneally (i.p.); CAPE-treated group received a single i.p. dose of CAPE (10 μmol kg?1 day?1); LC-treated group received 668 ppm of LC through drinking water; and CAPE + LC-treated group received an i.p. injection of CAPE (10 μmol kg?1 day?1) 12 h before the LC administration. The experiment was conducted for 10 consecutive weeks. LC caused a significant increase in testicular malondialdehyde, catalase, superoxide dismutase, glutathione-S-transferase activities, and sperm abnormalities and a significant reduction in testicular glutathione concentration, sperm count, sperm motility, and a live sperm percentage. Conversely, treatment with CAPE improved the reduction in the sperm characteristics, LC-induced oxidative damage of testes and the testicular histopathological alterations. Results indicate that LC exerts significant harmful effects on the male reproductive system and that CAPE reduced the deleterious effects of LC on male fertility.  相似文献   
27.
The investigated plant was known in northern Algeria with its vernacular name Mers’gousse and its rhizome is widely used as an ointment for the treatment of skin burns. The rhizome is rich in starch (0.23 ± 0.01 g/g wet mass, w.m.) and fat (8.0 ± 0.9 g/g w.m.), including sterols revealed by CGMS. In addition, the content of saponin, a substance known to hormonal activity, is of 0.041 ± 0.007 g/g w.m., far exceeding that of some common medicinal plants including ginseng. Regarding the antioxidant activity, the aqueous extract of Mers’gousse has a reducing power equivalent to 0.85 mg of vitamin C/g w.m. The elaborated ointments by two traditional procedures (cold and hot) present rheograms similar to that of Biafine® (ointment of Pharmacy) and which are correctly described by the Cresson’s model (R2 = 0.99). Finally, a test done on a volunteer has confirmed the effectiveness of the cream developed for the treatment of skin burns for which the plant is designed in the traditional medicine.  相似文献   
28.

Purpose of review

Cervical disc replacement (CDR) has emerged as a motion-preserving alternative to anterior cervical discectomy and fusion in selected cases. Despite favorable literature, CDR is not universally accepted because of concerns regarding bias in the existing literature. The purpose of this review is to identify the possible biases in the disc replacement literature.

Recent findings

Recent studies that compare CDR and ACDF have demonstrated equivalent or superior outcomes, lower rates of secondary surgery, and equivalent safety at medium- and long-term follow-up. In our review, we identified four types of bias that may affect the CDR literature: publication bias, external validity, confounding bias, and financial conflicts of interest.

Summary

Bias, whether intentional or unintentional, can impact the interpretation and outcome of CDR studies. Recognition of this issue is critical when utilizing the existing literature to determine the efficacy of CDR and designing future studies.
  相似文献   
29.
Artemisia campestris is used as antivenom and anti-inflammatory Tunisian folk medicine. Recently, increased oxidative stress was shown to play an important role in the etiology and pathogenesis of diabetes mellitus and its complications. This study was designed to examine the effects of A. campestris leaf aqueous extract (Ac) on alloxan-induced diabetic rats by measuring glycemia, lipid profile, lipid peroxidation (MDA), protein carbonyl content (PCO), advanced oxidation protein products (AOPP), activities of both non-enzymatic and enzymatic antioxidants. Results of our study showed an increase in blood glucose levels, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c), a decrease in high-density lipoprotein cholesterol (HDL-c) level and disturbed antioxidant enzyme activities (CAT, SOD, GPx) in the pancreatic tissue of diabetic rats. Furthermore, MDA, PCO and AOPP were elevated in the pancreas of the diabetic rats. The administration of Ac to diabetic rats at a dose of 200 mg kg−1 bw resulted in a significant reduction in glycemia, TC, TG, LDL-c, pancreas LPO, PCO and AOPP levels, CAT and GPx activities associated with an elevation of GSH content and SOD activity in comparison with diabetic group. We conclude that A. campestris aqueous extract may be effective for correcting hyperglycemia and preventing diabetic complications.  相似文献   
30.
Trace elements like zinc and copper play an important role in maintaining metabolic homeostasis in elderly subjects and is therefore expected to have a crucial effect on antioxidant mechanism. The objective of the present study was to investigate age-related variations of zinc, copper and antioxidant enzyme activities (superoxide dismutase: SOD, glutathione peroxidase: GPx and catalase: CAT) taking into account gender differences in a Tunisian elderly population. A group of 100 healthy elderly subjects (55–85 years old) were then separated in three sub-groups according to age intervals. A control group of 100 adults aged between 30 and 45 years was considered. The obtained results confirmed the decrease of plasma zinc level with age increase in both men and women. Moreover, prevalence of zinc deficiency increased with age: normal zinc concentration was obtained in about 60% of adults and only in 35% of the elderly subjects over 75 years old. No significant variation was obtained for copper concentration. GPx and SOD activities were lower in aged subjects in comparison to adults. Zinc and antioxidant enzyme activities were found to be negatively correlated to age. However, an investigation on a large size sample with various health and well-controlled dietary statuses should be conducted for a better understanding of the zinc or copper metabolism and their effect on oxidant stress during aging.  相似文献   
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