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41.
42.
We present an usual case of intracranial dural arteriovenous fistula with perimedullary and spinal cord venous plexus drainage and discuss its etiological, physiopathological, diagnostic and therapeutic aspects.  相似文献   
43.
The effect of thermal energy due to drilling around the facial nerve canal on the facial nerve was histopathologically evaluated in four guinea pigs. The bony canal of the facial nerve was drilled using a 3 mm diamond burr for one minute. The temperature changes on the facial nerve canal were noted before and after dissection. The temporal bones of the animals were histopathologically examined under light microscopy using haematoxylin & eosin (H&E) and solochrome cyanine staining for myelin, and immunohistochemical staining for neuronal nitric oxide synthase (nNOS). Compared to the control group, it was observed with H&E staining that there was oedema among the axonal fibres and with solochrome cyanine staining that the thickness of the myelin fibres was decreased, and that the severity and extent of nNOS activity was decreased in the axonal fibres. It was concluded that a temperature increase on the facial canal may potentially lead to inflammation of the nerve, and may also cause deterioration of nerve conduction to some extent.  相似文献   
44.
Mucinous cystadenocarcinoma of the salivary gland is a rare entity that has only recently been described. This lesion was included in the 1991 World Health Organization Classification as "papillary cystadenocarcinoma," and that same year the United States Armed Forces Institute of Pathology classified it as "cystadenocarcinoma with or without a papillary component." Only a small proportion of salivary gland tumors are adenocarcinomas. Most mucinous cystadenocarcinomas affect the major salivary glands, particularly the parotid. These are low-grade malignancies, and most that occur in the minor salivary glands show very little aggressive behavior. These tumors are histologically similar to adenocarcinomas of the gastrointestinal tract. It is often difficult to differentiate them from other neoplasms. The differential diagnosis includes mucoepidermoid carcinoma, acinic cell carcinoma, salivary duct carcinoma, nasal adenocarcinoma, and metastatic carcinoma. This report describes the case of an 80-year-old man who presented with a painless swelling in his right upper lip that had been present for 1 month. Fine-needle aspiration biopsy of the lesion revealed inflammatory cells without an epithelial component. The treatment was wide excision, and there was no recurrence during 6 months of follow-up. The pathological diagnosis was low-grade mucinous cystadenocarcinoma of a minor salivary gland.  相似文献   
45.
OBJECTIVE: The aim of this study was to determine the syndromic etiology of bilateral severe sensorineural hearing disorders in children and current etiological causes to reduce the cases in the unknown group. METHODS: This study was conducted on 550 students of five schools for the deaf in Istanbul and Zonguldak, Turkey. Otologic, audiologic, dysmorphologic, ophthalmologic and dental examinations were performed in all children. Familial and medical histories were obtained. RESULTS: The etiology of hearing loss was genetic in 346 (62.90%), acquired in 107 (19.45%) and unknown in 97 (%17.63) cases. A total of 619 malformations were defined in 550 children and 99 of them belonged to a syndrome. We identified 33 different syndromes for these 99 syndromic children. Syndromic etiology was found in 18.0% of the total and 28.61% of the subjects with genetic etiology. Most common syndrome was Waardenburg syndrome which occurred in 33 children. CONCLUSION: The incidence of hereditary hearing impairment is very high in developing countries compared to developed countries. Prevention is essential to reduce the incidence, multidisciplinary approach and genetic counselling are necessary in this regard.  相似文献   
46.
OBJECTIVE: The purpose of this study was to evaluate intraoperative and postoperative complications of alveolar distraction and outcome. STUDY DESIGN: Ten patients with alveolar ridge deficiencies were treated with alveolar distraction osteogenesis by means of intraosseous distractors (Lead system, Stryker Leibenger, Kalamazoo, Mich). The deficiencies were caused by atrophy after periodontal disease or atrophy after tooth extraction (n = 6), benign tumor resection (n = 2), trauma (n = l), or oligodontia in a case of ectodermal dysplasia (n = l). The location of the defects was the anterior mandible (7), posterior mandible (1), and anterior maxilla (2). The mean follow-up was 1.8 years, with a range of 10 months to 3 years. RESULTS: The mean alveolar distraction achieved in 10 cases was 8.7 mm (5-15 mm). The intraoperative and postoperative problems encountered were lingual (n = 3) and palatal (n = 2) displacement of the distracted segment, fracture of the distracted segment in a very thin alveolar bone (n = 1), and intraoperative bleeding (n = 1). CONCLUSION: Overall complication rate was 70%. However, most of the complications were minor and eliminated easily. Implant success rate was 85%.  相似文献   
47.
BACKGROUND: Heme oxygenase (HO)-1 system has been shown to provide protection against oxidative stress through the degradation of heme to biliverdin, free iron, and carbon monoxide (CO). This study investigated cytoprotective efficacy of CO at a low concentration on cold ischemia/reperfusion (I/R) injury of transplanted intestine. METHODS: Lewis rat recipients of syngenic orthotopic small intestinal transplantation with 6 hours UW cold preservation were either kept in room air (air-treated control) or exposed to CO (250 ppm) for 1 hour before and 24 hours after surgery. RESULTS: In air-treated grafts, mRNA levels for interleukin-6, intracellular adhesion molecule-1, cyclooxygenase-2, and inducible nitric oxide synthase promptly increased. Sequential histopathologic analysis of untreated grafts revealed initial rapid epithelial loss, subsequent recruitment of inflammatory infiltrates, and local hemorrhage in the lamina propria, which extended downward to the epithelial crypt and muscle layer with time. CO effectively blocked proinflammatory cascade during I/R injury, inhibited upregulation of inflammatory molecules and ameliorated intestinal tissue injuries. Beneficial effects of CO were associated with improved graft blood flow without inhibiting endogenous HO-1 activity. Recipient animal survival was significantly improved with CO to 100% versus 58% in air-treated controls. CONCLUSIONS: These results indicate a significant role for CO in protecting the intestine from cold I/R injury associating with small intestinal transplantation.  相似文献   
48.
Aim: To investigate the inflammatory effect and testicular damage on rats exposed to low level of electromagnetic fields (EMF) at 2.45?GHz microwave radiation.

Methods: Twenty two Wistar rats were divided into two groups. Group 1 was the control group and not exposed to EMF. Group 2 was exposed to low level EMF (average E-field 3.68?±?0.36 V/m, whole body average SAR, 0.0233 W/kg, in 10?g tissue) at 2.45?GHz for 1?hour/day for 30 consecutive days. At the end of the study, interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-32 (IL-32), C-reactive protein (CRP) were measured in rat serum and IL-6, IL-10, IL-32 were measured in rat testis tissue. Furthermore, testicular tissues were evaluated histopathologically in terms of spermatogenesis and coagulation necrosis.

Results: Serum IL-6 and CRP levels were found to be significantly different in the study group compared to the control group (p?<?.05), but no significant difference was found in serum IL-10, IL-32 levels and testis tissue IL-6, IL-10, IL-32 levels compared to the control group (p?>?.05). On the other hand, histopathological evaluation of testicular tissue revealed a significant difference in necrosis and spermatogenesis when compared with the control group (p?<?.05).

Conclusions: It may be concluded that low level EMF at 2.45?GHz increases inflammation and testicular damage and negative impact on male reproductive system function.  相似文献   
49.
INTRODUCTION: The aim of this study was to compare serum levels of leptin in women with unexplained infertility with fertile subjects. MATERIAL AND METHOD: Serum leptin levels of 27 infertile and 30 fertile women on day 3 of the menstrual cycle were assessed and compared in this prospective age and body mass index (BMI) comparable controlled study. RESULTS: The mean age in the infertile group was 29.3 (range, 23-38), while this figure was 28.9 (range, 19-39) in the fertile group; the mean BMIs were 24.5 (range, 20.6-27.8) and 25.0 (range, 21.8-28.7), respectively. The mean serum leptin level was significantly higher in women with unexplained infertility compared with fertile subjects. Considering normal weight subjects, mean serum leptin levels were increased significantly in the unexplained infertile group compared with the fertile group (7.2 (range, 4.3-10.4) versus 3.5 (range, 1.9-6.2)ng/ml, respectively; p<0.0001, Mann-Whitney U-test). The significant increase in serum leptin levels was observed also in overweight patients (6.8 (range, 1.3-5.2) versus 3.3 (range, 4.2-8.9)ng/ml, respectively; p<0.0001, Mann-Whitney U-test). CONCLUSION: A significant difference in serum leptin levels between unexplained infertile and fertile women suggests that this cytokine may be involved in pathophysiology of unexplained infertility.  相似文献   
50.
Objective The aim of this study is to demonstrate the process of detaching neural and surface ectodermal layers soon after the neurulation completes. Materials and methods Specific pathogen-free chicken egg embryos were used to investigate the neurulation procedure. Ten eggs were saved as controls. The other ten eggs were opened at the 30th hour of embryo development and cultured with Z-VAD-FMK (peptide caspase inhibitor) to investigate the results of the apoptosis inhibition. Embryos were placed and developed up to 48 h in the culture medium. To detect apoptotic cells between neural and surface dermal layers, immunoreactivity of p53 and terminal uridine deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were used. Results While the control group shows positive immunoreactivity of p53 and TUNEL-positive apoptotic cells at the site where the neural folds detach from the surface ectoderm, no TUNEL activity and no detachment were detected in the apoptosis-inhibited group. Conclusion As inhibition of apoptosis prevented the detachment of the neural and surface ectodermal layers from each other at the end of the neurulation, inhibition of apoptosis seemed to cause a considerable embryological error accounted for congenital dermal sinus tractus maldevelopment. This paper was presented at the 35th annual meeting of International Society of Paediatric Neurosurgery, 9–14 September 2007, Liverpool, England.  相似文献   
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