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131.

Purpose

Our study evaluated techniques for percutaneous gastrostomy (G)-tube placement without the use of a nasogastric (NG) tube. Instead, direct puncture of a physiologic air bubble or effervescent-enhanced gastric bubble distention was performed in patients with upper digestive tract obstruction (UDTO) or psychological objections to NG tubes.

Materials and Methods

A total of 886 patients underwent G-tube placement in our department during a period of 7?years. We present our series of 85 (9.6%) consecutive patients who underwent percutaneous G-tube placement without use of an NG tube.

Results

Of these 85 patients, fluoroscopic guided access was attempted by direct puncture of a physiologically present gastric air bubble in 24 (28%) cases. Puncture of an effervescent-induced large gastric air bubble was performed in 61 (72%) patients. Altogether, 82 (97%) of 85 G tubes were successfully placed in this fashion. The three failures comprised refusal of effervescent, vomiting of effervescent, and one initial tube misplacement when a deviation from our standard technique occurred.

Conclusion

The described techniques compare favorably with published large series on G-tube placement with an NG tube in place. The techniques are especially suited for patients with UDTO due to head, neck, or esophageal malignancies, but they should be considered as an alternative in all patients. Direct puncture of effervescent-enhanced gastric bubble distention is a safe, patient-friendly and effective technique.  相似文献   
132.
133.
Twenty-five percent of the world’s population could be suffering parasitic infestation. Highest prevalence is in underdeveloped agricultural and rural areas in the tropical and subtropical regions. In some areas incidence may reach 90% of the population. In contrast, some major economic projects intended to promote local development have, paradoxically, caused parasitic proliferation, e.g. bilharziasis in Egypt and Sudan and Chagas disease in Brazil. The commonest cosmopolitan gastrointestinal parasite is Entamoeba histolytica. Some intestinal parasite are endemic in temperate climates, e.g. Entrobius vermicularis. The AIDS epidemic has increased the prevalence and severity of parasitic disease, particularly Strongyloides stercolaris. Tropical parasites are seen in Western people who travel to tropical countries. Radiology has acquired a major role in diagnosis and management of gastrointestinal parasite infestations and their complications.  相似文献   
134.
Multiple primary tumors in patients diagnosed with hypopharyngeal cancer.   总被引:2,自引:0,他引:2  
OBJECTIVE: There have been few series to report on the incidence of multiple primary tumors associated with hypopharyngeal cancer. A unique consecutive patient group in a closed community who were treated by a single surgeon was available. The incidence and effect of multiple primary tumors were unknown. STUDY DESIGN: We sought to assess (1) the incidence of multiple primary tumors among patients with hypopharyngeal cancer who were treated at a tertiary center, (2) the incidence of synchronous and metachronous tumors, and (3) the location of these multiple primary tumors and their effect on patient survival. METHODS: We conducted a retrospective study of case notes of 150 consecutive patients with hypopharyngeal malignancy treated by a single surgeon between 1983 and 1998. Information was compiled from the patients' medical records and death data from the Family Health Services Authority. RESULTS: Thirty-four patients had multiple primary tumors (22.6%). There were 22 men and 12 women; piriform fossa tumor was seen in 21 men and 6 women, and postcricoid space tumor was seen in 6 women and 1 man. Second primary tumors were synchronous in 7 patients, subsequent to hypopharyngeal tumor in 5 patients, and antecedent to hypopharyngeal tumor in 14 patients. Eight patients had 2 primary tumors, of which 4 were synchronous, 4 were subsequent, and 8 were antecedent to hypopharyngeal malignancy. On the last review (2001), 3 patients were alive, and 31 had died: 17 had died from primary malignancy, 11 from another malignancy, and 3 from unrelated causes. CONCLUSION: The presence of second primary tumors in hypopharyngeal cancer is higher than previously reported, and their presence had a significant effect on the patients' survival.  相似文献   
135.
136.
PurposeRadiation therapy for mesothelioma remains challenging, as normal tissue toxicity limits the amount of radiation that can be safely delivered to the pleural surfaces, especially radiation dose to the contralateral lung. The physical properties of proton therapy result in better sparing of normal tissues when treating the pleura, both in the postpneumonectomy setting and the lung-intact setting. Compared with photon radiation, there are dramatic reductions in dose to the contralateral lung, heart, liver, kidneys, and stomach. However, the tissue heterogeneity in the thorax, organ motion, and potential for changing anatomy during the treatment course all present challenges to optimal irradiation with protons.MethodsThe clinical data underlying proton therapy in mesothelioma are reviewed here, including indications, advantages, and limitations.ResultsThe Particle Therapy Cooperative Group Thoracic Subcommittee task group provides specific guidelines for the use of proton therapy for mesothelioma.ConclusionsThis consensus report can be used to guide clinical practice, insurance approval, and future research.  相似文献   
137.

Background

Varicocele is known to be associated with infertility and sperm disorders. The exact cause of this ailment is not fully understood. There are limited numbers of studies where venous blood gases (VBGs) of varicocele veins were determined with conflicting results. Therefore, we have investigated the pattern of VBGs in both internal spermatic and external spermatic varicocele veins and correlation with semen quality parameters in infertile individuals who underwent left microsurgical varicocelectomy.

Methods

Patients (n?=?27) undergoing left microsurgical varicocelectomy at a tertiary care hospital, were included in the study. Before surgery, semen parameters and scrotal color Doppler ultrasonography was performed. During surgery, blood sample was drawn from varicocele veins (internal spermatic and external spermatic veins) and a peripheral arm vein of the same patient as a control. The VBGs of all veins under study were estimated and compared with each other. The VBGs were also correlated with various semen quality parameters. Data, expressed as Mean?±?SD, regarding VBGs in three veins were analyzed using one-way ANOVA. The correlation between VBGs and semen quality parameters was determined using Pearson’s correlation. Differences were considered significant at p?<?0.05.

Results

The pH was found to be higher (p?<?0.01) in the internal spermatic vein compared with the external spermatic and the peripheral veins. Partial pressure of oxygen (pO2) and oxygen saturation (sO2) were higher (p?<?0.01) in the internal spermatic vein compared with the peripheral vein. However, concentration of bicarbonate (HCO3) was lower (p?<?0.01) in both veins compared with the peripheral vein. Partial pressure of carbon dioxide (pCO2) was also lower (p?<?0.01) in the varicocele veins compared with the control vein.

Conclusion

The internal spermatic veins had higher pH and oxygen tension, but lower HCO3 and pCO2 levels compared with the control peripheral veins. External spermatic veins had lower pCO2 and HCO3 but other VBGs were similar to the peripheral veins. The shift of VBGs of internal spermatic vein toward arterial blood pattern may be a missing link to understand the pathophysiology of varicocele.
  相似文献   
138.
The nature of diversity of HLA-DRB1 exon 3   总被引:2,自引:0,他引:2  
Exon 3 of DRB1 is known to be polymorphic, but thought to be conserved within allelic groups. This implies that exon 3 polymorphisms would not need to be considered in evolutionary studies or clinical settings when assessing immunogenicity of allelic mismatches in stem cell transplantation. To further assess this, we determined the sequences of DRB1 exon 3 by hemizygote amplification and direct sequencing on 55 selected DNA samples containing 42 DRB1 alleles for which no exon 3 sequence data were previously available. The data confirmed the high degree of overall sequence conservation. The DRB4- and DRB5-associated alleles were completely conserved within their DRB1 groups. However, it could be shown that exon 3 is more diverse than previously expected. Multiple allelic differences within each group of DRB3-associated DRB1 alleles were found, without identifying unique group-related sequence motifs differentiating between these groups. For DRB1*1402 and DRB1*1406, it could be shown that they originated from DRB1*0302. In several samples previously typed as DRB1*1401, a novel DRB1 allele was identified: DRB1*1454. Thus, from a clinical viewpoint, the availability of exon 3 sequence information may be useful for optimizing typing as well as matching strategies. Additionally, it will allow for more detailed evolutionary studies, further elucidating the origin of alleles and the mechanisms driving sequence diversification.  相似文献   
139.
Recognition of special types of breast cancers by fine-needle aspiration (FNA) cytology may have prognostic implications but some difficulties still exist in the ability of cytopathologists to determine the tumor subtypes. Detailed cytomorphological features were studied in the four special and unusual types of breast cancer cases (8 cases of mucinous, 9 medullary, 9 apocrime, and 11 papillary) and compared between themselves and with those of 32 duct cell carcinomas, not otherwise specified (NOS). Papillary carcinomas were also compared with 10 benign papillary lesions. The significance of the differences was determined using Fishers' Exact Test of Probability. In mucinous carcinoma, the frequency of signet ring cells (62.5%), and background pools of mucin (87.5%) were significantly higher than those of duct cell carcinoma (NOS), medullary carcinoma, apocrine carcinoma, and papillary carcinoma (P = 0.0408 to < 0.0001). In medullary carcinomas, lymphomononuclear cell infiltration (100.0%) was observed in significantly higher number of cases than in papillary, mucinous, and apocrine types (P < 0.0001). Further, moderate to marked nuclear pleomorphism (100.0%) and nuclear irregularity (77.8%) was significantly higher than those of mucinous carcinoma and papillary carcinoma (P = 0.0294 to <0.0003). Abnormal apocrine cells and papillary formation, characterizing all the apocrine carcinomas and papillary carcinomas, respectively, were present in significantly lower number in other variants and in duct cell carcinoma (NOS) (P = 0.0002 to <0.0001). Glycogen vacuoles (63.6%) were observed in a significantly higher number of papillary carcinoma as compared to duct cell carcinoma (NOS), apocrine, and medullary carcinomas (P = 0.0047 to 0.0022). The significant parameters differentiating papillary carcinoma and benign papillary lesions were loose cohesive clusters (P = 0.001) and acinar formation by neoplastic cells (P = 0.0237). Histopathology reports available in 36 cases, confirmed the cytodiagnosis of carcinoma in all 35 cases and the benign lesion in one case. Cytological subtyping was confirmed in 13 of 16 special types of carcinomas and all the 15 duct cell carcinoma (NOS). Thus, special and unusual variants of duct cell carcinomas like mucinous, medullary, apocrine, and papillary have specific cytomorphological features, which differentiate them from one another and from duct cell carcinoma (NOS). However, differentiating features between papillary carcinoma and benign papillary lesions were very few in this study.  相似文献   
140.
Androgen mediating signaling is implicated in regulating the expression of reproductive related genes. Any deviation in the gene expression might be the ignitable precursor for genomic instability that inflames the genomic rearrangements and a leading cause of cancer. The main goal of this study was to determine the relationships between trinucleotide repeats of androgen receptor (AR), sex steroids, and sexual function in men presenting with reduced sperm motility. We investigated the singleton or combinatorial effects of the length of trinucleotide repeats of AR on reproductive hormones, clinical parameters, semen analyses, as well as sexual assessment function of 210 asthenospermic outpatients along with 125 normal subjects. Sexual assessment was executed using the International Index of Erectile Function (IIEF-15 score) which measures erectile function (EF), orgasmic function (OR), sexual desire (SD), intercourse satisfaction (IS), and overall satisfaction. Our findings suggest that long (>26 CAG)n repeats have an inverse correlation with circulatory FSH and T, whereas long (>25 GGC)n repeats have moderated affiliation with reduced sperm concentration. The study revealed a novel finding by exploring the negative correlation between elongated (CAG)n repeats and the cumulative IIEF-15 score, orgasm function (OR), and erectile function (EF) in asthenospermic men. This study examines the tri-nucleotide correlation with sexual function in Punjabi men enhancing our understanding of the regulatory mechanisms of sexual performance.

Abbreviations: AR: androgen receptor; IIEF-15 score: International Index of Erectile Function; EF: erectile function; OR: orgasmic function; SD: sexual desire; IS: intercourse satisfaction; FSH: follicular stimulating hormone; T: testosterone; NTD: N-terminal transactivation domain; DBD: DNA-binding domain; LBD: ligand binding domain; TNR: tri-nucleotide repeat  相似文献   

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