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51.
Trichilemmal cyst or pilar cyst is defined as a cyst containing keratin and its breakdown products. It is usually situated on the scalp with a wall resembling external hair root sheath. In this case report we present a 55-year-old man with multiple giant pilar cysts that were distributed over the whole body since childhood. One of the cyst on the chest was transformed to squamous cell carcinoma (SCC).  相似文献   
52.

Background

In August 2010 reports of a possible association between exposure to AS03 adjuvanted pandemic A(H1N1)pdm09 vaccine and occurrence of narcolepsy in children and adolescents emerged in Sweden and Finland. In response to this signal, the background rates of narcolepsy in Europe were assessed to rapidly provide information for signal verification.

Methods

We used a dynamic retrospective cohort study to assess the narcolepsy diagnosis rates during the period 2000–2010 using large linked automated health care databases in six countries: Denmark, Finland, Italy, the Netherlands, Sweden and the United Kingdom.

Results

Overall, 2608 narcolepsy cases were identified in almost 280 million person years (PY) of follow up. The pooled incidence rate was 0.93 (95% CI: 0. 90–0.97) per 100,000 PY. There were peaks between 15 and 30 year of age (women > men) and around 60 years of age. In the age group 5–19 years olds rates were increased after the start of pandemic vaccination compared to the period before the start of campaigns, with rate ratios (RR) of 1.9 (95% CI: 1.1–3.1) in Denmark, 6.4 (95% CI: 4.2–9.7) in Finland and 7.5 (95% CI: 5.2–10.7) in Sweden. Cases verification in the Netherlands had a significant effect on the pattern of incidence over time.

Conclusions

The results of this incidence study provided useful information for signal verification on a population level. The safety signal of increased narcolepsy diagnoses following the start of the pandemic vaccination campaign as observed in Sweden and Finland could be observed with this approach. An increase in narcolepsy diagnoses was not observed in other countries, where vaccination coverage was low in the affected age group, or did not follow influenza A(H1N1)pdm09 vaccination. Patient level analyses in these countries are being conducted to verify the signal in more detail.  相似文献   
53.
The abutment of an existing removable partial denture may require a crown restoration. Fabrication of a provisional restoration to fit the existing clasp assembly requires special consideration. This article presents a simple technique for fabrication of such provisional restorations. An alginate impression is made of the arch with the removable partial denture in place. The abutment tooth is then prepared, providing adequate clearance between the clasp assembly and the tooth preparation. Cold curing acrylic resin of proper shade is mixed and poured in the impression of the abutment tooth. The impression is then seated in the mouth and removed before the acrylic resin is completely polymerized. The provisional restoration is then separated from the partial denture, finished and polished.  相似文献   
54.
PURPOSE: This study evaluates bone regeneration of critical sized cranial vault defects in New Zealand white rabbits using four commercially available bone substitutes: OsteoSet (calcium sulphate pellets), DynaGraft Putty (demineralized bone matrix delivered in a poloxmer excipient), Norian CRS, and Bone Source (two commercially available calcium phosphate cements). MATERIALS AND METHODS: Critical sized defects 15 mm in diameter were created bilaterally in the parietal bones of 30 adult male New Zealand White rabbits. They were divided into three groups with ten animals in each. Bone healing was assessed clinically, radiographically, and histomorphometrically. Group 1 had calcium sulfate bioimplant on one side of the calvarium and an unfilled defect on the contralateral side. Group 2 had DBM putty on one side and Poloxamer gel on the contralateral side. Group 3, the Calcium phosphate cements (CPC), had Norian CRS on one side and Bone Source on the contralateral side. Five animals in each group were killed at 6 weeks and 12 weeks post operatively. RESULTS: All unfilled defects healed with fibrous scar, as did the Plaster of Paris and the poloxamer gel defects. Defects reconstructed with the demineralized bone matrix putty healed with bone throughout the entire defect. This was obvious clinically and radiographically where the defects appeared completely filled with a dense radiopaque tissue. The six-week group displayed new bone formation (87.1%) surrounding the remaining allogeneic particles. Resorption was evidenced by the presence of osteoclastic activity and by the significant decrease in the size of the demineralized bone particles. By 12 weeks, the demineralized bone putty bioimplant was almost completely replaced by new bone (95.5%). Both calcium phosphate cement groups (Norian CRS and Bone Source) had identical patterns of healing. They clinically were visible and firm and uniformly radiopaque with little evidence of new bone formation. Histologically the cement remained unresorbed with little new bone with in the defect at 12 weeks. CONCLUSIONS: The utilization of a demineralized bone matrix putty appeared to allow for complete closure of critical sized calvarial defects in New Zealand white rabbits with viable new bone at 12 weeks.  相似文献   
55.

Ethnopharmacological relevance

According to the Chinese, European, Iranian and Indian traditional medicines, oleo gum resin of Ferula assa-foetida (asafoetida) has therapeutic effects on different kinds of diseases. Some of these effects are related to the diseases of nervous system such as hysteresis and convulsion. In recent studies, some anti-epileptic and neuroprotective roles were also considered for it and we examined its possible role on treatment of peripheral neuropathy.

Material and methods

in vitro studies were carried out to identify the response of isolated sciatic nerves to different concentrations of oleo gum resin of asafoetida solved in Lock?s solution. Then, in vivo studies were conducted to evaluate its effect on amelioration of peripheral neuropathy in mice. Peripheral neuropathy was induced by intraperiotoneal injection of high doses of pyridoxine in adult Balb/c male mice. Tail flick tests were performed to identify the incidence of neuropathy in animals. After 10 days treatment with asafoetida, the efficiency of treatment was assessed by behavioral, electrophysiological and histological studies.

Results

in vitro experiments confirmed that incubating the nerves in aqueous extract of oleo gum rein of asafoetida increased the amplitude and decreased the latent period of nerve compound action potential (CAP). Nerve conduction velocity (NCV) and amplitude of CAP also improved in asafoetida treated animals. Histological and behavioral studies showed that asafoetida was able to facilitate the healing process in peripheral nerves.

Conclusions

in vitro experiments showed that asafoetida is a nerve stimulant and its administration in neuropathic mice exerted neuroprotecting effects through stimulating axonal regeneration and remyelination and decrement of lymphocyte infiltration.  相似文献   
56.

Purpose

To assess cardiothoracic structure and function in patients with pectus excavatum compared with control subjects using cardiovascular magnetic resonance imaging (CMR).

Method

Thirty patients with pectus excavatum deformity (23 men, 7 women, age range: 14-67 years) underwent CMR using 1.5-Tesla scanner (Siemens) and were compared to 25 healthy controls (18 men, 7 women, age range 18-50 years). The CMR protocol included cardiac cine images, pulmonary artery flow quantification, time resolved 3D contrast enhanced MR angiography (CEMRA) and high spatial resolution CEMRA. Chest wall indices including maximum transverse diameter, pectus index (PI), and chest-flatness were measured in all subjects. Left and right ventricular ejection fractions (LVEF, RVEF), ventricular long and short dimensions (LD, SD), mid-ventricle myocardial shortening, pulmonary-systemic circulation time, and pulmonary artery flow were quantified.

Results

In patients with pectus excavatum, the pectus index was 9.3 ± 5.0 versus 2.8 ± 0.4 in controls (P < 0.001). No significant differences between pectus excavatum patients and controls were found in LV ejection fraction, LV myocardial shortening, pulmonary-systemic circulation time or pulmonary flow indices. In pectus excavatum, resting RV ejection fraction was reduced (53.9 ± 9.6 versus 60.5 ± 9.5; P = 0.013), RVSD was reduced (P < 0.05) both at end diastole and systole, RVLD was increased at end diastole (P < 0.05) reflecting geometric distortion of the RV due to sternal compression.

Conclusion

Depression of the sternum in pectus excavatum patients distorts RV geometry. Resting RVEF was reduced by 6% of the control value, suggesting that these geometrical changes may influence myocardial performance. Resting LV function, pulmonary circulation times and pulmonary vascular anatomy and perfusion indices were no different to controls.  相似文献   
57.
58.
The purpose of the present study was to investigate the protective potential of Feijoa fruit extract on cadmium chloride (CdCl2)-induced testicular injury and pituitary–gonadal axis. Adult male Wistar rats were randomly divided into four groups: (a) control (normal saline, orally), (b) cadmium chloride (0.1 mg/kg, single dose, intraperitoneally), (c) Feijoa fruit extract (400 mg/kg, orally for 30 consecutive days) and (d) CdCl2 + Feijoa fruit extract. One day after receiving the last medicine, the LH, FSH, prolactin and testosterone concentration were assayed. Also, sperm parameters and tissue structure of the testis were evaluated. Administration of Feijoa fruit extract after CdCl2 injection in rats ameliorated sperm parameters such as sperm count, morphology, motility and sperm viability, increased levels of LH, FSH, prolactin and testosterone and improved testicular histology. According to the results of this study, it was shown that Feijoa can reduce the destructive side effects of CdCl2 on testicular tissue and sex hormones of the pituitary–gonadal pathway.  相似文献   
59.

Purpose

To evaluate whether the pretreatment apparent diffusion coefficient (ADC) heterogeneity parameters and their alterations, after one cycle of induction chemotherapy, can be used as reliable markers of treatment response to induction chemotherapy in patients with nasopharyngeal cancer.

Materials and methods

Ten patients were recruited and received induction chemotherapy (IC). Diffusion-weighted imaging was performed prior to, during, and after IC. The first-order ADC histogram parameters at the intra-treatment time-point were compared to the baseline time-point in the metastatic lymph nodes (LNs). Some ADC pretreatment parameters were combined with each other, employing discriminant analysis to achieve a feasible model to separate the complete response (CR) from the partial response (PR) groups.

Results

For ten patients, significant rise in Mean and Txt1Mean (p = 0.048 and 0.015, respectively) was observed in the metastatic nodes following one cycle of IC. Txt5Energy significantly decreased (p = 0.002). Discriminant analysis on pretreatment parameters illustrated that Txt5Energypre was the best parameter to use to correctly classify CR and PR patients. This was followed by Txt9Percentile75pre, Txt1Meanpre, and Txt2Standard Deviationpre.

Conclusions

Our results suggest that heterogeneity metrics extracted from ADC-maps in metastatic lymph nodes, before and after IC, can be used as supplementary IC response indicators.
  相似文献   
60.
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