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321.
ObjectiveThe resistin gene (RETN) ?420 C > G and + 299 G > A polymorphism was investigated in a case-control study from forty complex Pakistani families with coronary artery disease (CAD) history. Heritability of the susceptible/variant alleles was investigated from parent–offspring trios in these families.MethodResistin levels were determined from 239 individuals by enzyme-linked immunosorbent assay. Genotyping was performed using polymerase chain reaction and restriction fragment length polymorphism.ResultsElevated resistin levels were observed from CAD cases vs. controls (p < 0.0001). The RETN ? 420 C > G and + 299 G > A polymorphism was more prevalent in cases vs. controls (p < 0.0001). The transmission disequilibrium test revealed a significant association of the ? 420 and + 299 polymorphism with CAD (χ2 = 34.4, p < 0.0001 and χ2 = 31.6, p < 0.0001, respectively).ConclusionElevated resistin, and the RETN ?420 C > G and + 299 G > A polymorphism may contribute to familial CAD. The ? 420 and + 299 variant alleles are transmitted more frequently from parent to affected offspring. This is the first report on the association of the RETN + 299 G > A polymorphism with CAD.  相似文献   
322.

Introduction

Bezoars are clusters of ingested foreign bodies that form in the digestive tract; especially in the stomach.

Case presentation

A young girl aged 13 consulted for an epigastric mass. The abdominal ultrasound showed a heterogeneous intragastric mass and a CT scan revealed a gray mass, impregnated by the orally ingested contrast product. Fibroscopy confirmed the diagnosis of trichobezoar. An attempt to remove the trichobezoar by endoscopy was unsuccessful and a laparotomy with gastrotomy enabled the extraction of a huge stomach-shaped trichobezoar.

Discussion

Traditional factors usually involve gastric emptying disorders, problems following gastrectomy, a fibre-rich diet or gastric antisecretory drugs. Eating hair or other non-digestible materials or excessive consumption of indigestible foods may also lead to a bezoar. Fibroscopy remains the best technique for diagnosis and classification of bezoars. An abdominal CT scan will be used in cases of suspected intestinal obstruction or where injury may be involved, revealing the granite-like appearance of the bezoar in the stomach. Treatment is based on endoscopy, relayed by surgery in case of failure.  相似文献   
323.
A male child of four years is reported with Williams-Beuren Syndrome (WBS). It was not recognized initially when he presented with odd facies and developmental delay since early infancy. The diagnosis was established later when he developed hypertensive encephalopathy secondary to bilateral renal artery stenosis, a congenital anomaly that must be looked for in such patients. No echographic evidence of congenital heart disease was found. Blood pressure estimation on routine physical examination of every child is emphasized. The diagnosis is mainly clinical as the definitive chromosomal studies are presently not available in Pakistan.  相似文献   
324.
325.
A biological monitoring study was carried out in the Dutch flower-bulb culture to determine the relationship between respiratory occupational exposure to Z- and E-1,3-dichloropropene (Z- and E-DCP) and urinary excretion of two mercapturic acid metabolites, N-acetyl-S-(Z- and E-3-chloropropenyl-2)-L-cysteine (Z- and E-DCP-MA). Urinary excretion of Z- and E-DCP-MA, either based on excretion rates or on creatinine excretion, followed first order elimination kinetics after exposure. Urinary half-lives of elimination were 5.0 ± 1.2 hr for Z-DCP-MA and 4.7 ± 1.3 hr for E-DCP-MA and were not statistically significantly different. Calculated coefficients of variation indicated that the half-lives of elimination of Z- and E-DCP-MA were quite consistent inter- and intra-individually.Strong correlations (r 0.93) were observed between respiratory 8-hr time weighted average (TWA) exposure to Z-and E-DCP and complete cumulative urinary excretion of Z- and E-DCP-MA. Z-DCP yielded three times more mercapturic acid than E-DCP, probably due to differences in metabolism. Z- and E-DCP were excreted 45 and 14% as their respective mercapturic acid metabolites.A respiratory 8-hr TWA exposure to the Dutch occupational exposure limit of 5 mg · m–3 DCP would result in a complete cumulative excretion of 14.4 mg (95% confidence interval: 11.7–17.0 mg) Z-DCP-MA and 3.2 mg (95% confidence interval: 2.3–4.1 mg) E-DCP-MA.  相似文献   
326.
Solid-state compatibility and in vitro dissolution of direct-compressed sustained-release matrices of polyvinylacetate (PVAc) and polyvinylpyrrolidone (PVP) containing ibuprofen as a model drug were studied. Polyvinylalcohol (PVA) was used as an alternative water-soluble polymer to PVP. Differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) were used for characterizing solid-state polymer-polymer and drug-polymer interactions. The mechanical treatment for preparing physical mixtures of polyvinyl polymers and the drug (i.e. simple blending or stressed cogrinding) was shown not to affect the physical state of the drug and the polymers. With the drug-polymer mixtures the endothermic effect due to drug melting was always evident, but a considerable modification of the melting point of the drug in physical binary mixtures (drug:PVP) was observed, suggesting some interaction between the two. On the other hand, the lack of a significant shift of the melting endothermic peak of the drug in physical tertiary drug-polymer mixtures revealed no evidence of solid-state interaction between the drug and the present polymers. Sustained-release dissolution profiles were achieved from the direct-compressed matrices made from powder mixtures of the drug and PVAc combined with PVP, and the proportion of PVAc in the mixture clearly altered the drug release profiles in vitro. The drug release from the present matrix systems is controlled by both diffusion of the drug through the hydrate matrix and the erosion of the matrix itself.  相似文献   
327.
To estimate the quantitative relation between chronic co-exposure to airborne n-hexane, toluen, methyl ethyl ketone (MEK) and various markers of immune function such as proliferative response of peripheral blood lymphocytes and lymphocyte subpopulations, a group of workers employed in a shoe factory were examined and compared with the unexposed controls. A significant increase was observed in the proliferative response of the peripheral lymphocytes to 2.5 and 5 μg PHA in the exposed group compared with that of the control group. There was no significant change in the percentage of circulating CD3(+), CD4(+), CD8(+), CD19(+), CD16(+) lymphocytes even in those workers with 3.3-fold higher mean levels of urine 2,5-hexanedione (2,5-Hxdn) and approximately twofold higher mean levels of urine hippuric acid (HA) as compared to controls. No difference was also observed between the mean granulocyte, monocyte, lymphocyte percentages of the groups, but a significant increase was observed in mean serum C3 level of the workers. Our results suggest that while lymphocyte subpopulations and leucocyte percentages are not affected, the proliferative response of the peripheral lymphocytes is stimulated after chronic co-exposure to n-hexane, toluen and MEK at the defined levels.  相似文献   
328.
The range of dermal exposure to non-volatile compounds during spray painting was studied in a semi-experimental study involving three enterprises and 12 painters. A fluorescent tracer was added to the paint and deposition of the tracer on clothing and uncovered parts of the skin was assessed using video imaging and processing techniques. A container (volume 36 m(3)) was sprayed with a colourless laquer (varnish) containing 66.7 mg/l fluorescent whitening agent. All painters sprayed the outside of the container. Nine painters repeated the painting a second time and five also sprayed the inside of the container. The painters wore white Tyvek coveralls, but no gloves. Duration of spraying the outside ranged from 4 to 21 min with a mean of 10 min and the amount of paint sprayed ranged from 3.0 to 12.8 l (mean 6.6 l). The mass of tracer deposited on the coverall ranged from 2.2 to 471 microg (90th percentile 256 microg), whereas, mass deposited on skin (i.e. the hands, wrists, and face) ranged from 0.01 to 52 microg tracer (90th percentile 20 microg). The quantity of tracer on the coverall was three times higher after spraying the inside of the container compared to spraying the outside, whereas the quantity on the skin was similar in both cases. On average 10% of the surface area of the coverall and skin was exposed during spraying the outside. Exposures, expressed in units of mass per area exposed were slightly higher for skin compared to coverall.In this study, deposited mass of tracer was correlated with an alternative exposure metric, i.e. surface area exposed multiplied by the duration of exposure, which has been proposed as a surrogate for uptake. Using a quantitative fluorescent tracer technique, it could be demonstrated that body parts which showed the lowest mass of tracer had the highest exposure as mass per surface area. Compared to other techniques which only determine mass, the ability to identify and quantify the actual surface area exposed is a clear advantage of the quantitative fluorescent tracer technique.  相似文献   
329.
PURPOSE: This study has two objectives: (1) using ultrasound (US) as a tool for measuring subcutaneous (S) and intra-abdominal; preperitoneal (P) and visceral (V) fat thickness. (2) Assessing the relationship between selected anthropometrical variables and US-measured S, P and V fat also evaluating the contribution of abdominal fat accumulation in development of liver steatosis. METHODS AND MATERIALS: Sixty-eight obese patients (aged 43.9+/-9.3 years) and 40 non-obese subjects (aged 34.03+/-9.0 years) were recruited to this study. Height, weight (W), waist (WC) and hip circumferences were measured. Body mass index (BMI) and waist to hip ratio (WHR) were calculated. A linear-array probe (7.5 MHz) was used to measure S and P. A convex-array probe (3.5 MHz) was used for measuring V and assessing liver fatty infiltration. RESULTS: In 45 (66%) patients, there were diffuse liver fatty changes. Liver steatosis showed significant correlation with V (r=0.57), P (r=0.38) and S (r=0.37). It also correlated with W (r=0.52), BMI (r=0.6), WC (r=0.45) (P<0.0001). V positively correlated with BMI (r=0.62), W (r=0.55), WC (r=0.52) and WHR (r=0.33). P correlated with WC (r=0.29), WHR (r=0.36) and W (r=0.34), but not with BMI, height and age. A significant correlation was found between S and BMI (r=0.73), W (r=0.65), and WC (r=0.57) (P<0.0001). CONCLUSION: Obese patients showed thicker S, P, and V. Liver steatosis correlates significantly with both anthropometrical data; BMI, WHR, WC, and W, and with abdominal V, P, and S fat. V fat can be used as a good predictor for the possibility of different metabolic disorders and liver disturbances as steastosis.  相似文献   
330.
The intriguing concept of a receptive field evolving through Hebbian learning, mostly during ontogeny, has been discussed extensively in the context of the visual cortex receiving spatial input from the retina. Here, we analyze an extension of this idea to the temporal domain. In doing so, we indicate how a particular spike-based learning rule can be described by means of a mean-field learning equation and present a solution for a couple of illustrative examples. We argue that the success of the learning procedure strongly depends on an interplay of, in particular, the temporal parameters of neuron (model) and learning window, and show under what conditions the noisy synaptic dynamics can be regarded as a diffusion process.  相似文献   
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