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41.
We studied the ultrastructure of spermiogenesis and of the mature spermatozoon of Taenia parva, an intestinal cestode of the common genet, Genetta genetta. Spermiogenesis in T. parva is characterized by the growth of the axoneme externally to a cytoplasmic extension. After a slight rotation, the free flagellum fuses with the cytoplasmic extension. This pattern corresponds to type III spermiogenesis according to the scheme proposed by Ba and Marchand. The zone of differentiation lacks both striated roots associated with the centrioles and the intercentriolar body between them. Nevertheless, the flagellar rotation of about 45 degrees is observed in this species. On the other hand, the mature spermatozoon of T. parva, as in other cestodes, is filiform, tapered at both extremities and lacks mitochondria. The presence of a single crest-like body, periaxonemal sheath, and transverse intracytoplasmic walls are also characteristic ultrastructural features. The pattern of spermiogenesis and the ultrastructural organization of the spermatozoon of T. parva are compared with the available data on cyclophyllideans and, in particular, species of the family Taeniidae.  相似文献   
42.
A primary focus of neurointensive care is monitoring the injured brain to detect harmful events that can impair cerebral blood flow (CBF), resulting in further injury. Since current noninvasive methods used in the clinic can only assess blood flow indirectly, the goal of this research is to develop an optical technique for measuring absolute CBF. A time-resolved near-infrared (TR-NIR) apparatus is built and CBF is determined by a bolus-tracking method using indocyanine green as an intravascular flow tracer. As a first step in the validation of this technique, CBF is measured in newborn piglets to avoid signal contamination from extracerebral tissue. Measurements are acquired under three conditions: normocapnia, hypercapnia, and following carotid occlusion. For comparison, CBF is concurrently measured by a previously developed continuous-wave NIR method. A strong correlation between CBF measurements from the two techniques is revealed with a slope of 0.79±0.06, an intercept of -2.2±2.5 ml∕100 g∕min, and an R2 of 0.810±0.088. Results demonstrate that TR-NIR can measure CBF with reasonable accuracy and is sensitive to flow changes. The discrepancy between the two methods at higher CBF could be caused by differences in depth sensitivities between continuous-wave and time-resolved measurements.  相似文献   
43.
The arch of the great saphenous vein presents numerous tributaries. Misappreciation of their anatomical variations might cause recurrence after surgical treatment of varices. We dissected 54 inguino-femoral regions of fresh, black African corpses. Our purpose was to study the anatomical variations in the vein confluents of the arch of the great saphenous vein; its positions in relation to the external pudendal artery; establish palpable anatomical markers for its surgical approach. The conventional type in a ‘vein star’ shape was not the most frequent. Upper or abdominal common vein produced through the merging of superficial veins of the anterior abdominal wall and genital or internal common vein were more frequent. An anterior saphenous vein was found in 23 cases. The external pudendal artery crossed beneath the arch of the great saphenous vein cross in 56% of cases and previously in 44% of cases. On average, the top of the arch of the great saphenous vein was projected out 10.88 cm from the ventral and cranial iliac spine, 3.83 cm from the pubic tubercle and 4.19 cm from the inguinal ligament. In view of our results, variations are real. Knowing and taking them into account are essential to prevent recurrences after surgical treatment of varices of the pelvic limb.  相似文献   
44.
In 2002, human T-cell leukemia virus type 1 (HTLV-1) and HTLV-2 seroprevalence was 0.16% (8/4,900) in blood donors from Dakar, Senegal. Most of the positive donors originated from the country's southern region. Seven donors were infected by HTLV-1 (of cosmopolitan subtype), and one was infected by HTLV-2. These data highlight the problem of transfusion safety in this area where HTLV-1-associated lymphoproliferative and neurological diseases are endemic.  相似文献   
45.
Methotrexate (MTX), which has been used for years in cancer treatment, is now being proposed as a first-line treatment for rheumatoid arthritis (RA), despite its potential side effects. The aim of this study was to investigate the short-term efficacy, safety and relative cost of low-dose MTX for the treatment of RA. We carried out an open, nonrandomized trial in which patients received a 7 mg injection of MTX once per week, with clinical and biological follow up. A single physician performed the weekly assessments, which involved evaluation of the duration of morning stiffness, the number of night awakenings, the number of painful and swollen joints and Ritchie's index. Blood cell count and erythrocyte sedimentation rate were determined monthly. Twelve RA patients were enrolled in the trial, over a mean treatment period of 356 +/- 175 days. A significant improvement was observed in all variables except the number of swollen joints. Ritchie's index decreased from a mean of 31.8 +/- 11.85 to 6.5 +/- 8.98 (p<1.6 x 10- 4). Minor adverse reactions were observed but none indicated treatment withdrawal: 6 cases of nausea, 2 of a moderate increase in transaminase activity, 1 of bronchitis, in which the responsibility of MTX was not definitely established and 3 cases in which hemoglobin levels decreased. The monthly cost of the treatment, including the drug itself and laboratory tests, is lower than that of gold salt injection. Three issues of key importance in our region were investigated in this study: 1) the possible desire to become pregnant of female patients undergoing MTX treatment. In addition, some of the young and unmarried patients did not understand or appreciate the contraceptive effects of the treatment; 2) poor compliance with the treatment due to limited financial resources. Many patients did not regularly attend for their follow-up appointments and many stopped taking the medication. One third of the patients were lost to follow-up during this study; 3) the prevalence of chronic hepatitis, which may limit the use of MTX in our region. Serological tests should be performed before the treatment is started and a liver biopsy is recommended for patients with chronic hepatitis B or C.  相似文献   
46.
This study evaluated the attitudes and practices of the personnel with respect to the prevention of nosocomial infections in a hospital environment. We carried out a qualitative survey of all categories of personnel between July 1998 and March 1999, at the five regional hospitals in Senegal (Thiés, Kaolack, Saint-Louis, Diourbel, and Louga). Data were collected in two ways: using a questionnaire to evaluate knowledge and by observing the attitudes and practices of the personnel. Hands were rarely washed before and after each procedure and surgical washing was often performed in poor conditions. The decontamination of soiled equipment was ineffective. Reusable instruments were washed directly with bare hands or by individuals wearing used surgical gloves. The equipment used for sterilization was dilapidated and unsuitable and the norms for sterilization were seldom respected. Circulation in the region of the operating theatre was disorganized, if not anarchic. The personnel had a high risk of contamination from blood. Biomedical waste was not decontaminated: it was collected poorly and disposed of directly into the environment. None of the sites visited had a program of waste incineration. In conclusion, at the sites visited, there is a high risk of nosocomial contamination during care and the reuse of equipment, for both the staff and the patients treated.  相似文献   
47.
Between May and October 2000, the Regional Health Office of Kolda Region in the south of Senegal, West Africa, reported an epidemic of an unknown illness characterized by thoracic pain, dyspnea and edemas of limb and face. The epidemic covered a radius of approximately 40 km (24 miles) between the districts of Kolda and Sedhiou in Kolda Region. Cases were mostly men whose age ranged between 12 and 60 years old. Investigation revealed that they had been exposed to pesticides distributed by the government to groundnut farmers. The signs and symptoms suggested intoxication with carbamates, carbofurans, and possibly thiram, contained in the pesticides distributed with the groundnut seeds. Government distribution created an excessive use of pesticides in the farms, and consequently an overexposure of the subjects who handled the seeders, especially young males but also a small proportion of women who worked in the groundnut fields. Many of these subjects, not accustomed to handle pesticides, came to overestimate the quantity of product to fill the seeder. It should be noted that the policy of distribution of pesticides in Senegal, which presents risk of poisoning, was not systematically accompanied by sufficient information on the danger of the products and of certain precautions that should be taken during their use.  相似文献   
48.
The control of pertussis remains a worldwide concern. Little has been documented about its epidemiology in Africa. The authors have studied pertussis in a prospective cohort of children in a rural West African community over a 13-year period comprising time before and after introduction of a vaccination program. Children under age 15 years who were residents of the Niakhar study area in Senegal were followed prospectively between January 1984 and December 1996 for the occurrence of pertussis. Morbidity and mortality rates were extremely high before the launch of immunization. Crude incidence was 183 per 1,000 child-years at risk under age 5 years, with a 2.8% case-fatality rate. After the introduction of the vaccination program, overall incidence dropped rapidly and dramatically-by 27% after 3 years and 46% after 6 years. The decline in incidence involved all age groups but was most substantial in the group under age 5 years and was particularly pronounced in unvaccinated infants. The median age of acquisition of the disease rose steadily with population vaccine coverage. This study shows the tremendous magnitude of the disease burden in children and the rapid decline after vaccination, and it suggests a strong herd-immunity effect.  相似文献   
49.
50.
Thirteen cases of genital tuberculosis are reported to make emphasis onto the difficulties of diagnosis, management and prognosis of the disease. The average age of the patients is 31 years. Most of them were under 30. The circumstances of diagnosis were variable. The diagnosis was essentially made thanks to histology. The evolution was favorable under antibiotics. But clinical sequels as amenorrhea and infertility are frequent.  相似文献   
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