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1.
Phosphate metabolites and steroid hormone receptors of benign and malignant breast tumors. A Nuclear Magnetic Resonance study 总被引:1,自引:0,他引:1
Phosphorous 31 (31P) nuclear magnetic resonance (NMR) spectra were recorded from perchloric acid extracts of benign and malignant breast tumors. The spectra were correlated with the histopathologic diagnosis and the steroid receptor status of the tumor. Higher relative content of the lipid-derived metabolite glycerolphosphoethanolamine (GPE), the high-energy nucleoside phosphates (nucleoside-diphosphate [NDP], nucleoside-triphosphate [NTP]), and sugar esters of uridine diphosphate (UDPS) appeared in the carcinomas. Malignant tumors also showed a lower ratio of phosphoethanolamine to phosphocholine (PE/PC) than benign conditions. Lower content of the lipid-derived metabolite glycerolphosphocholine (GPC) and high content of the high-energy compound phosphocreatine (PCr) were associated with malignant tumors having high content of estrogen receptors (ER). High PCr content was also associated in the carcinomas with high progesterone receptors (PgR) content. In the benign tumors NDP and NTP were higher in tumors with high PgR content. The authors suggest that 31P magnetic resonance spectroscopy (MRS) of the breast can provide additional variables to diagnose malignancy, and when combined with magnetic resonance imaging (MRI), invasive procedures may be avoided. It also seems that levels of PCr and GPC obtained from the spectra can serve as markers to hormonal receptor status of breast carcinomas, and may be used in addition to the ER and PgR content to improve prediction of the response to hormonal therapy. Additional development requires in situ MRI and MRS combined studies. 相似文献
2.
D A Ollendorff M D Fejgin M Barzilai I Ben-Noon A B Gerbie 《American journal of obstetrics and gynecology》1987,157(1):71-72
The charts of all patients hospitalized between 1978 and 1983 with proved ectopic pregnancies at Northwestern Memorial Hospital, Chicago, and Meir Hospital, Kfar-Sava, Israel, were reviewed. Eighty-four patients with ectopic pregnancies had endometrial tissue available for histologic analyses. Review of the endometrial curettings revealed that the most common endometrium associated with ectopic pregnancy was secretory (39.4%). Proliferative endometrium present 19% of the time was as common a finding as Arias-Stella phenomenon. This study shows that any type of endometrium lacking trophoblasts may be associated with an ectopic pregnancy. The lack of decidual reaction or Arias-Stella phenomenon should not alone lower the clinician's index of suspicion. 相似文献
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Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
5.
Nir Lubezky Ur Metser Ravit Geva Richard Nakache Einat Shmueli Joseph M. Klausner Einat Even-Sapir Arie Figer Menahem Ben-Haim 《Journal of gastrointestinal surgery》2007,11(4):472-478
Background Recent data confirmed the importance of 18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in the selection of patients with colorectal hepatic metastases for surgery.
Neoadjuvant chemotherapy before hepatic resection in selected cases may improve outcome. The influence of chemotherapy on
the sensitivity of FDG-PET and CT in detecting liver metastases is not known.
Methods Patients were assigned to either neoadjuvant treatment or immediate hepatic resection according to resectability, risk of
recurrence, extrahepatic disease, and patient preference. Two-thirds of them underwent FDG-PET/CT before chemotherapy; all
underwent preoperative contrast-enhanced CT and FDG-PET/CT. Those without extensive extrahepatic disease underwent open exploration
and resection of all the metastases according to original imaging findings. Operative and pathological findings were compared
to imaging results.
Results Twenty-seven patients (33 lesions) underwent immediate hepatic resection (group 1), and 48 patients (122 lesions) received
preoperative neoadjuvant chemotherapy (group 2). Sensitivity of FDG-PET and CT in detecting colorectal (CR) metastases was
significantly higher in group 1 than in group 2 (FDG-PET: 93.3 vs 49%, P < 0.0001; CT: 87.5 vs 65.3, P = 0.038). CT had a higher sensitivity than FDG-PET in detecting CR metastases following neoadjuvant therapy (65.3 vs 49%,
P < 0.0001). Sensitivity of FDG-PET, but not of CT, was lower in group 2 patients whose chemotherapy included bevacizumab compared
to patients who did not receive bevacizumab (39 vs 59%, P = 0.068).
Conclusions FDG-PET/CT sensitivity is lowered by neoadjuvant chemotherapy. CT is more sensitive than FDG-PET in detecting CR metastases
following neoadjuvant therapy. Surgical decision-making requires information from multiple imaging modalities and pretreatment
findings. Baseline FDG-PET and CT before neoadjuvant therapy are mandatory.
The abstract was presented before the 58th Cancer Symposium of the Society of Surgical Oncology, Atlanta, GA, USA, 2005, and
before the 2005 Congress of the American Hepato-Pancreato-Biliary Association, Fort-Lauderdale, FL, USA. 相似文献
6.
Marouni MJ Barzilai A Keller N Rubinstein E Sela S 《International journal of medical microbiology : IJMM》2004,294(1):27-33
Group A streptococcus (GAS) is the principle etiologic agent of bacterial pharyngotonsillitis and a wide range of other diseases. Failure to eradicate GAS from patients has been documented in 5-30% of patients with pharyngotonsillitis, in spite of the continued sensitivity of GAS to penicillin and other beta-lactams. It was recently proposed that eradication failure might be attributed to the ability of GAS to maintain an intracellular reservoir during antibiotic treatment. We have previously shown that strains derived from patients with bacterial eradication failure, despite antibiotic treatment (persistent strains), adhered to and were internalized by cultured epithelial cells more efficiently than strains that were successfully eradicated. Since, penicillin and other beta-lactams do not penetrate well into mammalian cells, intracellular survival of GAS is crucial in order to persist during prolonged antibiotic treatment. In this study, we compared the survival of GAS strains from cases of eradication failure and eradication success, using an epithelial cell culture model. We found that persistent strains show significantly increased intracellular survival, compared to the 'eradication success' strains. This finding supports the idea that an intracellular reservoir of GAS plays a role in the etiology of antibiotic eradication failure. 相似文献
7.
Ella Israeli Batya Raz Hedwiga Kerner David Barzilai 《Breast cancer research and treatment》1985,6(3):241-248
The levels of cyclic adenosine 3:5-monophosphate (cAMP) and cyclic guanosine 3:5-monophosphate (cGMP) were studied in dimethylbenz(a)anthracene (DMBA)-induced mammary tumors of Sprague-Dawley rats and in human breast cancer. In the rat carcinomas, these levels were significantly lower than in non-malignant tissues when calculated on the basis of DNA content, but higher (cAMP) or equal (cGMP) when calculated on the basis of weight. In human breast cancer the cyclic nucleotide levels were higher than in non-malignant tissues according to both methods of calculation. No correlation was found in human carcinomas between the cyclic nucleotide levels and mitotic index, nuclear grade, tumor size, or lymph node involvement. The rat tumors were subclassified according to state of differentiation, mitotic index, and state of development. Not all the sub-groups had cAMP levels different from normal values. Differences in cAMP levels between the sub-groups could not be correlated with tumor growth rates and/or mitotic index. Thus, cyclic nucleotides may not be useful in prognosis of breast cancer. 相似文献
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BACKGROUND: Intentional selective occlusion of the arterial blood supply to tumors of abdominal organs is a well established therapeutic procedure. Several reports described gas accumulation at the infarcted sites. These gas collections are usually nonsuppurative; however, the differential diagnosis should include abscess formation. CASE REPORT: We present a 59-year-old patient in whom the splenic artery was accidentally ligated during gastrectomy surgery, with resultant splenic infarction. Gas accumulation was diagnosed by sonography and CT studies. To the best of our knowledge this is the first report ever published in the English medical literature describing nonsuppurative gas formation within an abdominal organ, caused by accidental ligation of its main arterial supply during surgery. SUMMARY: Possible theories regarding this noninfectious gas accumulation are discussed and the differential diagnosis between abscess formation and noninfectious gas accumulation is emphasized. Establishing the correct diagnosis is of big clinical importance as the treatment of choice is completely different in each one of these entities although the imaging features, in ultrasound as well as in CT, are somewhat similar. 相似文献
10.