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91.
Melanin production in a medullary thyroid carcinoma   总被引:1,自引:0,他引:1  
J N Marcus  C A Dise  V A LiVolsi 《Cancer》1982,49(12):2518-2526
Melanin production by a medullary thyroid carcinoma (MTC) is reported and discussed. Immunohistochemically, the tumor cells contained calcitonin; by electron microscopy, they bore numerous, heterogeneous granules similar to those described previously in MTCs. One small focus of tumor was pigmented. Here, melanosomes in different stages of maturation were found in dendritic cells that ramified among granule-bearing cells. The remarkable phenotypic divergence in this solitary, nongerm cell neoplasm is unusual but not so surprising in light of the APUD nature and neural crest origin of both the melanocyte and the thyroid C cell, which gives rise to MTC. The authors view the calcitonin and melanosome phenotypes as closely related tumor clones evolving from a common precursor neoplastic cell. This unique "experiment of nature" adds to the set of rare human tumors that make melanin "ectopically."  相似文献   
92.
Early amniocentesis at 11-14 weeks gestation was evaluated in 100 consecutive patients to see how this technique compares with later amniocentesis. There were no complications as a consequence of the procedure or related pregnancy losses of chromosomally normal fetuses. Samples obtained from three (3%) patients showed insufficient cell growth; two of these patients elected a repeat procedure, which yielded a normal karyotype in each case. There were five abnormal karyotypes, one of which was a culture artifact; in the latter case, repeat amniocentesis at 15 weeks yielded a normal result. Of the 95 pregnancies with normal karyotypes, 94 were progressing normally at follow-up, and one patient elected pregnancy termination because of maternal indications. It appears that early amniocentesis may be an attractive alternative to traditional amniocentesis, in that it provides results at an earlier gestational age and may avoid certain disadvantages of chorionic villus sampling.  相似文献   
93.
Endoscopic management of acute calculous cholangitis   总被引:16,自引:0,他引:16  
Acute cholangitis is associated with significant morbidity and mortality. Endoscopic drainage procedures have been shown to be a safe and effective mode of treatment in acute cholangitis. As there is paucity of large series on endoscopic management of acute cholangitis, a study was performed to evaluate safety and efficiency of endoscopic biliary decompression in acute cholangitis. The study included 89 consecutive patients (mean age 55 ± 15 years; range 35–70 years; 50 males) with acute cholangitis requiring biliary drainage. Main presenting features were upper abdominal pain (84%), fever with chills (90%) and jaundice (74%). Altered sensorium, hypotension, features of peritonitis and acute renal failure were present in 15, 11, 18 and 5%, respectively. Endoscopic procedures performed were endoscopic sphincterotomy (ES) with stone extraction (n= 40); ES with endoscopic nasobiliary drainage (ENBD; n= 30); ENBD without ES (n= 8); and ES with stent placement (n= 11). Of the 89 patients, 85 (95%) responded within 48–72 h. Endoscopic common duct clearance could be achieved in 58 of 78 (74%) patients, whereas in 11 patients undergoing stent placement, stone extraction was not attempted. Complications included post-sphincterotomy bleed (n= 2), retroduodenal perforation (n= 1) and acute pancreatitis (n= 1) with an overall complication rate of 4.4%. All the complications were seen in patients undergoing ES with stone extraction. Mortality was 3.3%. In conclusion, endoscopic biliary drainage is a safe and effective mode of treatment for acute cholangitis. Endoscopic nasobiliary drainage or stent placement is safer than ES in acute cholangitis as an initial step.  相似文献   
94.
95.
A myxoid liposarcoma of the vulvar perineum in a 15-year-old girl is described. The tumor recurred as a poorly differentiated round cell liposarcoma and resulted in the patient's death. Clinicians and pathologists should be aware that this tumor may rarely present on the vulva.  相似文献   
96.
BACKGROUND: Both fine-needle aspiration (FNA) and frozen section (FS), although useful in preoperative and intraoperative management, have their advantages and pitfalls when used in the diagnosis of salivary gland lesions. The accuracy of each of these modalities has been assessed separately in many studies; a direct comparison of these techniques on a large cohort has not been well studied. Herein, we determine the relative accuracies of both FNA and FS in the diagnosis of salivary gland lesions. METHODS: We reviewed a cohort of 220 cases of parotid gland FNA with histologic follow-up; FS was performed in 57 cases (26%). The sensitivity, specificity, and accuracy of FNA and FS were determined with respect to the final histologic diagnosis. For these calculations, benign diagnosis was considered negative, whereas a malignant diagnosis was considered positive. In addition, we re-reviewed the FNA and FS slides in cases that had conflicting FNA and FS results. RESULTS: Of the 220 cases examined, the FNA diagnoses were as follows: benign (n = 142), malignant (n = 52), indeterminate (n = 14), and nondiagnostic (n = 12). Correlating these findings with the histologic findings, nine cases (4%) were false negative, whereas 12 (5%) were false positive. The sensitivity, specificity, and accuracy for FNA when diagnostic were 86%, 92%, and 90%, respectively. In 57 cases with FS, seven (12%) were false negative, whereas none were false positive. The FS was able to change to benign four diagnoses that were malignant by FNA and provide a diagnosis for five nondiagnostic FNAs. The sensitivity, specificity, and accuracy for FS were 77%, 100%, and 88%, respectively. The sensitivity, specificity, and accuracy for FNA and FS combined were 90%, 100%, and 95%, respectively. CONCLUSIONS: Both FNA and FS provide a similar accuracy. FS may be useful if FNA is nondiagnostic and may also be useful in confirming or refuting malignancy in some cases. Hence, both techniques are complementary to each other in the diagnosis of salivary gland lesions.  相似文献   
97.
The follicular variant of papillary carcinoma (FVPTC) is characterized by follicular growth pattern and tumor cells with appropriate nuclear features of papillary carcinoma. However, occasionally these lesions may show focal or multifocal instead of diffuse distribution of nuclear features of papillary carcinoma. Such lesions can be underdiagnosed as benign follicular nodule. Previous studies have shown that cytokeratins, especially 19, are helpful in differentiating papillary carcinoma from other benign and malignant follicular patterned lesions. In this study, we applied monoclonal antibodies to CK5/6/18, CK18, CK10/13, CK20, CK17, and CK19 to paraffin sections of formaldehyde-fixed tissue from 26 cases of FVPTC with multifocal distribution of papillary cancer nuclei, 10 cases of usual variant of papillary carcinoma, 1 case of Warthin's tumor-like papillary carcinoma, and 2 cases of the columnar cell carcinoma. CK19 stained strongly and diffusely all cases of papillary carcinoma. FVPTC cases showed strong staining of the areas with papillary cancer nuclei in all cases and moderate to strong staining in areas of tumor without obvious nuclear features of papillary cancer. Normal thyroid parenchyma adjacent to the tumor nodule showed focal staining in most cases; however, tissue away from the tumor nodule failed to show any staining. All cases of usual type of papillary carcinoma, 2 of columnar cell carcinoma, and 1 Warthin's tumor-like papillary carcinoma showed strong and diffuse staining with CK19 and failed to show any staining of adjacent normal thyroid parenchyma. Similar but less intense staining patterns were seen with CK17 and CK20. The control group, consisting of cases of follicular adenoma, follicular carcinoma, and hyperplastic nodule, showed no staining with CK19. We suggest that if one is using immunohistochemistry to aid in the diagnosis of cases of FVPTC with multifocal distribution of nuclear features of papillary cancer, an antibody panel comprising CKs 17, 19, and 20 may prove helpful. In addition, we hypothesize that the staining of adjacent nontumorous thyroid parenchyma with CK19, seen only in cases of FVPTC, suggests that some factors secreted/produced by this particular tumor may lead to modification in keratin expression of surrounding follicular epithelium.  相似文献   
98.
99.
Endoscopic management of postoperative bile leak   总被引:14,自引:0,他引:14  
Significant bile leak is an uncommon but serious complication of biliary tract surgery. Of twenty-five patients presenting with postoperative bile leak, 11 had complete tie-off of common bile duct and required surgery, while the remaining 14 had injury without complete obstruction and could be managed by endoscopic methods. Of these 14 cases, bile leak occurred from the cystic duct in 11 patients and from the common hepatic duct, right hepatic duct and left hepatic duct in one patient each. Endoscopic procedures performed included sphincterotomy alone (four patients), sphincterotomy and stent placement (seven patients) and sphincterotomy followed by nasobiliary catheter drainage (three patients). There was no technical failure and bile leak was stopped in all patients. One patient died of haemobilia 5 days after stent placement. When technically feasible, postoperative bile leak can be managed safely and effectively by endoscopic methods, obviating the need for surgical reexploration.  相似文献   
100.
Formorethan40years,epinephrinehasbeenthevasopressoragentofchoiceforcardiopulmonaryresus-citation(CPR)andcurrentlyisstillbesuggestedbyAmericanHeartAssociationandwidelyuseinclinicCPR.However,recentstudiesquestionthevalueofepinephrineadministrationdu  相似文献   
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