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1.
A prolonged school-based outbreak of measles provided an opportunity to study "vaccine-modified" mild measles and secondary vaccine failure. Thirty-six (97%) of 37 unvaccinated patients had rash illnesses that met the Centers for Disease Control clinical case definition of measles, but 29 (15%) of 198 vaccinated patients did not, primarily because of low-grade or absent fever. Of 122 patients with seroconfirmed measles, 10 patients (all previously vaccinated) had no detectable measles-specific IgM and significantly milder illness than either vaccinated or unvaccinated patients with IgM-positive serum. Of 108 vaccinated patients with seroconfirmed measles, 17 patients (16%) had IgM-negative serology or rash illnesses that failed to meet the clinical case definition; their mean age (13 years), age at the time of vaccination, and time since vaccination did not differ from those of other vaccinated patients. The occurrence of secondary vaccine failure and vaccine-modified measles does not appear to be a major impediment to measles control in the United States but may lead to underreporting of measles cases and result in overestimation of vaccine efficacy in highly vaccinated populations.  相似文献   
2.
Socialization games, designed to reinforce prosocial behavior between moderately and severely mentally retarded aggressive institutionalized women, were presented to two groups on 12 occasions over 8 weeks, randomly interspersed with 12 sessions of arts and crafts or filmstrip stories. Half of the sessions were presented in the morning and half in the afternoon. Video-taped observations of interpersonal behavior for 10 minutes after each session were analyzed in terms of friendly, unfriendly, and inactive behavior, and the distance of each subject from each other subject was measured. The rate of friendly behavior was significantly greater after the games and was higher in morning than afternoon sessions. The games also significantly decreased interpersonal distance. Both unfriendly behavior and inactivity were higher after the "placebo" sessions. The relevance of these results to institutional programming was discussed.  相似文献   
3.
To evaluate the role of the renin-angiotensin-aldosterone system in the hypertension associated with primary hyperparathyroidism, we measured plasma renin activity and aldosterone concentration before and after maneuvers to suppress and stimulate this system in 11 hypertensive patients with primary hyperparathyroidism. We also measured plasma or urinary norepinephrine concentration to examine the role of catecholamines in the hypertension. The results were compared with an age- and race-matched control population. While the mean plasma aldosterone concentrations were normal, the mean plasma renin activity in response to furosemide stimulation was subnormal in subjects with hyperparathyroidism. Plasma or urinary norepinephrine concentrations were within the normal range. Thus a specific abnormality of the renin-angiotensin-aldosterone system or catecholamines could not be identified in these hypertensives with primary hyperparathyroidism.  相似文献   
4.
Primary cardiac osteosarcomas are rare and usually originate in the left atrium. In contrast, osteosarcomas metastatic to the heart most commonly involve the right cardiac chambers. This case report describes an unusual primary cardiac osteosarcoma, initially observed as a slowly growing, densely calcified mass of the left ventricle with subsequent secondary pulmonary metastasis. Although cardiac tumors may be asymptomatic, this patient had recurrent bouts of ventricular tachyarrhythmia. We describe the clinical, echocardiographic, and radiological observations spanning 6 years and the gross and microscopic features at autopsy.  相似文献   
5.
BACKGROUND: The chemotherapy drugs methotrexate, vinblastine, doxorubicin, and cisplatin have shown activity in patients with recurrent or metastatic squamous cell carcinoma arising from the upper respiratory or alimentary passages of the head and neck. This study was undertaken to assess the antitumor activity and toxicity profile of the drug combination methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) in this patient population. METHODS: Patients with histologically confirmed unresectable, recurrent, or metastatic squamous cell carcinoma arising from the upper respiratory or alimentary passages of the head and neck were treated with MVAC over a 4-week cycle. The doses were as follows: 30 mg/m2 of methotrexate on Days 1, 15, and 22; 3 mg/m2 of vinblastine on Days 2, 15, and 22; 30 mg/m2 of doxorubicin on Day 2; and 70 mg/m2 of cisplatin on Day 2. The total cumulative dose of doxorubicin was not to exceed 450 mg/m2. Treatment was discontinued after four cycles for those whose disease remained stable. Patients were evaluated for chemotherapy response, progression free survival, and survival. RESULTS: Thirty-six patients were accrued onto this study between April 1993 and February 1996. One patient (3%) with a history of cardiac heart failure was declared ineligible. Severe leukopenia (leukocyte count < 2000 cells/m3) was observed in 55% of the patients during the first cycle of treatment and in 81% of the patients during the entire course of their treatment. The overall objective response rate over the first 4 cycles of treatment was 46% (90% confidence interval [CI], 33-60%). Two of the 18 patients who responded had a complete response. The median time to progression was 19 weeks, and 1-year progression free survival rate was 17% (95% CI, 8-36%). The median survival was 49 weeks, and the 1-year survival rate was 43% (95% CI, 29-63%). Among the 22 patients with unresected residual or recurrent disease, the median time to progression was 11 weeks, and 1-year progression free survival rate was 14% (95% CI, 5-39%), and median survival was 24 weeks, and the 1-year survival rate was 36% (95% CI, 21-63%). Among the 13 patients with metastatic disease, the median time to progression was 26 weeks, and the 1-year progression free survival rate was 23% (95% CI, 9-62%), the median survival was 54 weeks, and the 1-year survival rate was 54% (95% CI, 33-89%). CONCLUSIONS: Methotrexate, vinblastine, doxorubicin, and cisplatin is an active chemotherapy regimen in patients with recurrent or metastatic squamous cell cancer arising from the upper respiratory or alimentary passages of the head and neck.  相似文献   
6.
BACKGROUND: Previous observations have suggested that leiomyosarcomas, and especially gastrointestinal leiomyosarcomas, may be less responsive to cancer chemotherapy than other histologic types of non-osseous sarcomas; however, this difference has not been characterized well until quite recently, with the recognition of the special identity of gastrointestinal stromal tumors (GIST). Prior to the general acceptance of this new histologic classification, we decided to study patients with gastrointestinal leiomyosarcomas in concert with other leiomyosarcomas for relative responsivity to a combination cytotoxic regimen developed specifically for leiomyosarcomas. PATIENTS AND METHODS: Adult patients with advanced leiomyosarcomas received intravenous chemotherapy as outpatients with dacarbazine 750 micrograms/m2, mitomycin 6 mg/m2, doxorubicin 40 mg/m2, and cisplatin 60 mg/m2 on day 0, with granulocyte macrophage colony stimulating factor (GM-CSF, sagramostim) 250 mcg/m2 given s.c. every 12 hr on days -6 to -3 and on days 1-14 of each 4-week treatment cycle. Our original plan to escalate dacarbazine doses to 1000 mg/m2 following cycle one was abandoned after the first six patients because of toxicity. RESULTS: We studied 21 patients with GIST and 18 patients with other types of leiomyosarcomas, for a total of 131 treatment cycles, with a median of four cycles per patient in each of the two groups of patients. Toxicity was significant, with 33% having grade 3 vomiting at some time during treatment. Grade 3 leukopenia occurred in 42%, and grade 3 thrombocytopenia was observed in 68% of our patients. In one patient, grade 4 pulmonary toxicity developed during the fourth cycle, and this was considered a major factor in her death. Objective tumor regression was observed in one of 21 (1.8%) (95%CI = 0-14.5%) GIST and in 11 of 18 (61%) (95%CI = 38-84%) other leiomyosarcomas, including eight of 10 uterine cases. In five cases, we interrupted chemotherapy to attempt complete surgical excision of residual tumor, and four of the patients were rendered apparently free of disease. Median survivals for the two groups have been similar with 16.7 months (95%CI = 8.8-27.5 months) for the GIST and 17.5 mos (95%CI = 10.9-35.3%) for the other leiomyosarcomas. Three patients with uterine leiomyosarcomas are still alive more than 2 years after completing this chemotherapy and subsequent secondary surgical excision (+/- irradiation) and two of them are free of disease. CONCLUSIONS: While this regimen is ineffective against GIST, its value against uterine leiomyosarcomas deserves further study in a larger population.  相似文献   
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We report the clinical and histopathologic findings of bacillary angiomatosis involving the palpebral conjunctiva with concomitant infection by cytomegalovirus and Mycobacterium species in a patient with acquired immune deficiency syndrome. After debulking, the conjunctival tissue was studied with the use of light and electron microscopy; stains for bacteria, acid-fast bacilli, and Bartonella species; and immunohistochemical studies for cytomegalovirus and herpes simplex virus. We observed the typical histopathologic findings of bacillary angiomatosis, the presence of bacilli stained by the Steiner and Steiner method, and the electron microscopic demonstration of bacilli consistent with Bartonella species. Immunohistochemistry confirmed infection with cytomegalovirus, which had been suggested by characteristic cytologic abnormalities. Acid-fast bacilli were also found in the excised tissue. Patients with bacillary angiomatosis of the conjunctiva may have infections with multiple additional microorganisms.  相似文献   
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