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1.

Background

Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.

Objective

We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.

Methods

HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.

Results

The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.

Conclusion

We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas.  相似文献   
2.
Obstructive sleep apnea syndrome (OSAS) is a common condition characterized by repetitive sleep‐induced collapse of the upper airways. It is associated with increased risk for hypertension, ischemic heart disease, cerebral stroke, and traffic accidents. In contrast, gastroesophageal reflux disease (GERD) is a very common disorder defined as various symptoms or esophageal mucosal damage generated by the abnormal reflux of gastric contents into the esophagus. Patients with OSAS have been reported to have a high prevalence of gastroesophageal reflux (GER) symptoms. The increase of transdiaphragmatic pressure in parallel with the large negative intrathoracic pressure produced during apnea events may directly lead to GER. In addition, some studies have demonstrated improvement in GERD with the application of continuous positive airway pressure, most consistently effective treatment for OSAS. However, GER dose not occur with every apnea. Moreover, the common conditions observed in patients with OSAS, including obesity or alcohol ingestion, are also predisposing factors for GER. A more recent investigation in over 1000 subjects failed to show a causal link between both diseases. Thus, the potential relationship between OSAS and GERD remains controversial. Inconsistencies in definitions of both diseases or sampling biases may contribute to the confusing results.  相似文献   
3.
The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease.  相似文献   
4.
We used morphological, biochemical and immunohistochemical methods to assess the response of Müller cells after experimental lensectomy-vitrectomy in rabbits. We observed widened intercellular spaces between the Müller cells and nerve fibers of ganglion cells, and increased electron opacity in the Müller cells of eyes injected with silicone oil. No apparent morphological changes were detected in the Müller cells of air-injected eyes. The specific and total activities of Müller cell-marker enzymes (glucose 6-phosphatase and glutamine synthetase) showed an initial increase, followed by a decrease. Glial fibrillary acidic protein immunoreactivity was not found in the Müller cells of the normal rabbit retina but was exhibited after surgery. Our results showed that markers of Müller cells associated with glycogenolysis and/or gluconeogenesis, glutamate-glutamine cycle and cytoskeletal protein metabolism were affected by the experimental lensectomy-vitrectomy.  相似文献   
5.
6.
OBJECTIVE: To evaluate the influence of the age at disease onset on the clinical symptoms, laboratory findings, treatment, and complications of microscopic polyangiitis (MPA). PATIENTS: From 1999 to 2001, we encountered 4 MPA patients with disease onset at age 65 or older (average 77.3, all were female: the elderly group). For comparison, 4 MPA patients with disease onset a 64 years or younger (average 44.7, two were male: the non-elderly group) were used. RESULTS: There was no statistically significant difference in clinical features between the two groups. All patients in the elderly group were referred to our hospital, because of fever of unknown origin or suspicion of connective tissue disease. The elderly group had a longer duration from the first admission to the start of treatment. Renal biopsies were done in all of the non-elderly group and one of the elderly group. The diagnosis of the other 3 patients of the elderly group was based on muscle or nerve biopsy, showing necrotizing vasculitis. At the time of diagnosis, antibodies to myeloperoidase (MPO-ANCA) were positive in 7 of 8 patients (87.5%). 2 patients of the non-elderly group were died of heart failure and hepatic failure by cyclophosphamide (CYC). The other 6 patients achieved substantial improvement. CONCLUSIONS: Muscle or nerve biopsy helped clinical management of elderly patients when renal biopsies could not be done. IVCY was relatively safe and effective treatment for MPA in elderly as well as non-elderly patients.  相似文献   
7.
The efficacy and safety of MTX in active RA were evaluated based on patient medical records. The study population consisted of 460 patients with active RA who had received no prior MTX therapy and started it at our hospital between August 1998 and December 2003 (80 men and 380 women with a mean age of 59.3 years). After 24 weeks of MTX therapy, 61.3% of patients showed a 20% improvement, and 30.4% achieved a 50% improvement according to the ACR criteria. The cumulative rate of patients who continued MTX therapy for 48 weeks was 0.567. During the observation period, 260 patients (56.5%) experienced 304 adverse reactions. 52 patients (11.3%) discontinued treatment because of adverse reactions, and 10 patients (2.2%) died. The adverse reactions that occurred in at least 1% of patients were: abnormal hepatic function (31.7%), infection (6.1%), gastrointestinal symptoms (5.0%), stomatitis (3.9%), hematological abnormalities (3.5%), fracture (3.5%), malignant tumor (2.6%), interstitial pneumonia (2.0%), cerebrovascular or cardiovascular disorder (2.0%), headache (1.7%), eruption (1.3%), and alopecia (1.1%). Adverse reactions were more common in the elderly and patients with advanced stage disease. This study reaffirms the therapeutic benefit of MTX, but suggests that careful monitoring is of great importance.  相似文献   
8.
The blocking effects of complement-dependent sperm immobilizingantibodies in the sera of infertile women and monoclonal antispermantibodies against humans and mice on fertilization were investigated.The hemizona assay (HZA) and sperm penetration assay (SPA) wereused to study the inhibitory effects of sera from 22 infertilepatients positive for sperm immobilizing antibodies. Use ofthese tests allowed us to differentiate whether the antibodyblocked sperm—zona pellucida tight binding and/or spermpenetration into the ooplasm. The zona pellucida penetrationassay (ZPA) was also used to study the effects of four monoclonalantibodies (mAbs) on human sperm penetration into the zona pellucida.Seven mAbs against murine spermatozoa were tested for theirinhibitory effects on in-vitro fertilization (IVF) and HZA inmice. Of 22 patient sera with sperm immobilizing antibodies,21 (95.5%) inhibited HZA attachment and penetration, whereasthis did not occur in any of 13 patient sera without these antibodies.However, 19 of 22 (86.4%) patient sera with sperm immobilizingantibodies and eight of 13 (61.5%) patient sera without theseantibodies inhibited the SPA. Two (2C6, 1G12) of four mAbs againsthuman spermatozoa showed strong inhibitory effects in all theassays (HZA, ZPA and SPA). One mAb (3B10) did not inhibit HZAbut blocked ZPA and SPA. Another mAb (H6-3C4) seemed to haveno inhibitory effects on fertilization. Two (Vx 5 and Vx 8)of seven mAbs against murine spermatozoa inhibited IVF in micebut did not block mouse HZA. These findings suggest that antispermantibodies block fertilization at specific stages. Some of themmay inhibit sperm capacitation and thus prevent all processesof fertilization that follow. Some other antibodies may notaffect capacitation and sperm binding to zona pellucida butinhibit the acrosome reaction, followed by the blocking of spermpenetration through zona pellucida and ooplasm.  相似文献   
9.
Recently, several angiotensin I-converting enzyme (ACE) inhibitors and an angiotensin II receptor blocker were demonstrated to have a clinically important prophylactic effect in migraine. ACE is one of the key enzymes in the rennin-angiotensin-aldosterone system, which modulates vascular tension and blood pressure. In humans, serum ACE levels are strongly genetically determined. Individuals who were homozygous for the deletion (D) allele showed increased ACE activity levels. To investigate the role of ACE polymorphism in headache, we analyzed the ACE insertion (I)/deletion (D) genotypes of 54 patients suffering from migraine with aura (MwA), 122 from migraine without aura, 78 from tension-type headache (TH), and 248 non-headache healthy controls. The ACE D allele were significantly more frequent in the MwA than controls (p<0.01). The incidence of the D/D genotype in MwA (25.9%) was significantly higher than that in controls (12.5%; p<0.01; odds ratio=5.26, 95% confidence interval: 1.69-16.34, adjusted for age and gender). No differences in the remaining groups were found. Our results support the conclusion that the D allele and the D/D genotype in the ACE gene is a genetic risk factor for Japanese MwA. There seems to be a possible relationship between ACE activity and the pathogenesis of migraine.  相似文献   
10.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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